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Jul21
FALCIPARUM MALARIA PRESENTING AS ACUTE PANCREATITIS
ABSTRACT:
We report a case of Acute pancreatitis in a case of falciparum malaria. The incidence of other complications are common. The mechanism of this rare complication and its pathophysiology is reviewed. ( The Ind. Pract. 2005; 58(10): 649-651).

KEYWARDS:
Malaria (Plasmodium Falciparum Malaria), Complications, Acute Pancreatitis, Serum Amylase, Serum Lipase.

INTRODUCTION:
Malaria, a burning problem in tropical countries and a disease of global concern has a major preponderance in India affecting life of all ages and races. It complications are responsible for taking away a major fraction of patient death in our country. The acute and chronic complications are many. As far as falciparum malaria is concerned it has diverse life threatening complications. Acute pancreatitis is very rare but devastating complication of falciparum malaria which we have put as a case report.

CASE REPORT:
A 41 year old male presented in general medicine ward in October 2004 with history of fever of 5 days which was associated with chill and rigor. There was yellow coloration of urine and conjunctiva for 3 days and gradual decrease of urination for 2 days. There was 5-6 episodes of loose motions and vomiting and pain abdomen (confined to epigastic region) for 10 hours before admission. The patient was not an alcoholic. There was no previous such history of pain abdomen. There was no history of trauma to abdomen. He is not a known case of DM, HTN, SCD APD. There was no history of taking any drug.

On examination the patient was average built, conscious with moderate pallor moderate icterus with mild oedema (bilateral pedal) no lymphadenopathy with a pulse rare 92 per minutes, regular, BP 100/70 mm of HG, without any signs of dehydration. Abdominal examination revealed mild distension and diffuse tenderness maximum at epigastric area, smooth tender hepatomegaly ( 5 cm below the costal line) moderate non tender spenomegaly (3 cm below the left costal margin), mild ascites and diminished bowel sound. Cardiovascular system, respiratory system and other systemic examination revealed no abnormality.

INVESTIGATION
HB- 9.8gm%
TLC – 10,200/mm2
DC – N69%, E-1%, L30%, B0%, M0%
Widal test – Negative
Microfilaria – Negative
Serum Bilirubin – Total 13.3mg%, Direct 10.4%
RBS – 172mg%
SGOT – 11IU/L
SGPT – 138IU/L
Serum Alkaline Phosphatase – 110 IU/L
S. Urea – 106mg%
S.Creatinine – 4.2mg%
Serum Amylase – 2050 IU/L
Serum Lipase – 3050IU/L
Serum Ca++ - 7.2gm%
HBs Ag – Negative
HCV Ag – Negative
Malaria Parasite – Slide +ve
QBC – pfr (++)
ICT – pfr (+)

Ultrasonogram revealed hepatosplenomegaly and features of acute pancreatitis and mild ascites. CT scan of abdomen also revealed hepatosplenomegaly ascites and acute pancreatitis.

On the basis of blood report patient was treated along the line of complicated malaria with artesunate, injection cefipime, metronidazole injection, inject able pantoprazole, intravenous fluid and one unit of blood transfusion. The patient was conservatively managed for acute pancreatitis and nasogastric tube aspiration and nil orally for 5 days. The patient recovered within a span of 7 days after which the MP was negative. Serum amylase, serum lipase, Urea, Creatinine and bilirubin came down to 100IU/L, 230 IU/L, 28mg %, 0.8 mg%, 4.2 mg% respectively on 7th day. Repeat USG of abdomen revealed only mild hepatomegaly. The patients was relieved on 14th day of admission.

DISCUSSION:
Pancreatitis clinically presents with upper abdominal pain accompanied by elevated levels of pancreatic enzymes i.e amylase and lipase. The type such as acute chronic haemorrhagic, necrotic are distinguished by history, clinical , biochemical and radiological findings.

Acute pancreatitis presents as neusea, vomiting , anorexia, abdominal pain. Out of numerous causes of acute pancreatitis malaria is rare. But it must be looked for in tropical country like India with high prevalence of malaria.

Falciparum malaria is the deadest among all other types of malaria with varied complications, multiorgan involvement and diverse sequlae. The parasite may affect pancrease causing acute pancreatitis or acute haemorrhagic pancreatitis. The clinical and laboratory findings follow similar pattern of other causes of acute pancreatitis.

The pathogenesis may be initiated by sequestration of parasite in the organ, blood vessels or ducts, damaging acinar cells by premature activation of digestive enzymes with cells. The damaged acinar cells initiate inflammation, activation of platelets and compliment system, which leads to release to cytokines (e.g TNF - , IL – 1, NO, PAF), free radicals and other vasoactive substances. These further directly damage the gland and may cause pancreatic oedema, necrosis, ischaemia and capillary leak syndrome. Tehse lead to a vicious inflammatory cycle damaging further pancreatic tissue. Association of sepsis further leads to organ damage and complications.

Malaria presenting with classical symptoms and signs of acute pancratitis along with other organ involvement may be difficult to correlate. The abdominal pain may be sharp, sudden or constant may be localized to epigastric,periumbilical, block or lower chest. But common presentation in malaria is fever, icterus with distended abdomen, diffuse or localized tenderness. Grey Turners signs or Cullen sign may be noted in advanced cases.

Blood count and chemistry panel usually distinguishes pancreatitis from other acute abdominal causes, Test of malaria (MP, Slide , QBC, ICT) determines malaria aetiology, Increased TLC, Hyperglycaemia, decreased Ca++, Increased alkaline phsophatase, S. Amylase, S. Lipase reflects pancreatic damage.

Serum amylase has low sensitivity (75-92%)and Specificity (20-60%) but is used to confirm acute pancreatitis , when upper limit is raised 3-6 times of normal specificity increases. Serum amylase level is raised 2-12 hours after pancreatic insult and peaks 12-71 hours after.

Serum lipase having sensitivity 86-100% and specificity of 50-99%. Serum lipase raised 4-8 hours after signs and symptoms and peaks at 24 hour and decrease over 8-14 days.

Other recent markers are immunoreactive cationic trypsin, pancreatic elastase – 1 and phospholipase.

Although USG and Ct scan of abdomen makes the diagnosis easy, cholangio-pancreatography may be accompolished bu ERCP or MRCP.

The primary treatment of acute pancreatitis with malaria is to treat the cause i.,e malaria. The treatment of acute pancreatitis is primarily supportive providing adequate hydration, pain relief and pancreatic rest by nasogastric suction and nil orally. Antibiotics are added to prevent sepsis or necrotic pancreatitis with setting of multiorgan involvement.

The prognosis of acute pancreatitis with malaria depends on the stage of presentation, haemorrhagic pancreatitis bears poor prognosis.

CONCLUSION
Falciparum malaria which has various complications may present as an acute pancreatitis, along with other organ affection. This is a rare condition and must be in mind of clinicians when patient presenting with clinical features of malaria, with pain abdomen , vomiting and localized abdominal tenderness.

A high index of suspicion and thorough clinical examination and investigation are the ways to diagnose the complication i.e, acute pancreatitis. Specific antimalarial drugs are the primary modalities of treatment, along with the conservative management for acute pancreatitis.

REFERENCE:
1. Von Sonnenberg F, Los Cher T, Nothdurgt HD, Prufer L @ Pubmed . PMID : 3519146.
2. Michelle M, Piet Zak MD (1) Dan W Thomas MD (2).
3. Parenti DM, Steingberg W, Kang P – Infectious causes of ac pancreatitis , 1996; 13(4) – 356-71.


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Jul21
ATYPICAL PRESENTATION OF HERPES SIMPLEX ENCEPHALITIS
ABSTRACT:
Herpes simplex virus (HSV) encephalitis usually caused by HSV1 is gravest and commonest form of acute encephalitis. It is usually present with fever, headache, seizure, confusion, stupor and coma. Psychosis may be associated with these manifestations. Here we are reporting a case of clinico-radiologically diagnosed case of HSV encephalitis that present predominantly with psychosis and make diagnostic dilemma. (The Ind. Pract 2005; 58 (1):38-39.

KEY WORDS:
Herpes Simplex Virus, Encephalitis, Psychosis

INTRODUCTION:
Among all acute encephalitis 10% of cases are due to HSV. It is usually present like other acute encephalitis. Psychosis is a distinct feature due to involvement of temporal lobe, medial and orbital part of frontal lobe. CT scan imaging may identify the cerebral lesion at temporal and frontal lobe. Fatality rate varies between 30-70%. Early presumptic diagnosis with the help of clinical examination, C.S.F. examination and radio imaging and early therapeutic intervention with acyclovir may save the life of the patient. C.S.F. PCR is the diagnostic approach now for herpes simplex encephalitis.

CASE REPORT:
A 38 year old male presented with psychotic behavior or last 20 days. He was febrile for about 6 days 2 weeks back. Fever was typically low grade, contunuosu. With the onset of fever he starts incoherent talk.

He was also unable to recognize the known persons. His speech frequency was very much decreased and he was reluctant to take food. He was admitted to local private hospital on days of his illness where his CS examination was done. At that time his CSF cell count was 296/cumm, mostly lymphocytes, protein 72mg% and sugar 48mg%. His treatment was started there in the line of TB meningitis but patient gradually deteriorated. Due to his uncontrolled psychotic behavior, psychatric consultation was done, treated with haloperidol. But patient’s psychosis did not improve. Rather his bladder and bowel control was lost.

On the day of our hospital admission patient was febrile, drowsy, disoriented, illusion and auditory hallucination were present. Sensory aphasia, inhoherent talks were associated with those features. His plantar reflex was B/L extensor and gait unsteady. Investigation revealed WBC 11100/cumm. ESR 15mm and RBS 127mg% DC – N 51% and L 49%. Repeat C.S.F. examination was done which revealed total WBC count 76/cumm mostly lymphocytes, protein 28 mg% and sugar 78 mg%. CSF contained plenty of RBC. CT scan of brain showed hypodense area at B/L temporal and fronto medial lobe (Fig. 1 and Fig 2) suggestive of HS encephalitis. Treatment was started with acyclovir 500 mg IV 8 hourly with monitoring pf S. Creatinine level. On 10th day of therapy patient’s psychosis decreased, was able to recognize his wife and son and plantar become flexor, though auditory and gustatory hallucination still persisted.

DISCUSSION:
HSV 1 and 2 infection can manifest a spectrum of illness from stomatitis and progenitor lesion to facial nerve palsy and encephalitis. Encephalitis is due to HSV1. The unique localization of the disease in the temporal lobe may be explained by the virus route of entry into the CNS1. The lesion takes the form of haemorrhagic necrosis of temporal and medial part of frontal lobe2. Lesion of these areas in imaging study with CT or MRI is highly suggestive3. Patients with Japanese encephalitis display abnormalities of thalamus, basal ganglia and midbrain. Other forms of viral encephalitis imaging studies are non- specific.

Manifestations like hallucination, anosmia, personality changes, bizarre behavior or delirium, aphasia usually observed in H.S. encephalitis. Temporal lobe seizure usually seen in ECG. Affection of memory can be recognized in the convalescent state.

CSF often cloudy due to RBC as well as WBC protein may be raised but sugar usually normal. In minority of cases, low sugar in CSF may confuse with TB or fungal meningitis. Test for detection of HSV in the CSF by PCR are useful in diagnosis while virus is replicating in first few days of illness.

Our patient presented at OPD after 3 weeks of illness when the absolute ways to establish the diagnosis is fluorescent antibody study and viral culture of brain tissue obtained by biopsy. Avoiding this hazardous procedure, we treated the patient with empirical antiviral agents based on compatible clinical, radiological and CSF findings. Treatment option for HSE is acyclovir in the dose of 30 mg /kg/day for 10-14 days5. Our patient was responding well with above mentioned treatment. After one month follow up , patient improved with mild psychotic behaviour, gaustatory hallucination and depression.

REFERENCES:
1. Davis L.E., Joshson R.T.: An explanation for localization of herpes simplex encephalitis. Ann Neural 1979; 5: 2.
2. Adams H. Miller D: Herpes Simplex encephalitis: A clinical and pathological analysis of twenty two cases. Post Grad M.D. J 1973; 49:93.
3. Davis J.M. et al : CT of herpes simplex encephalitis with clinico pathological correlation. Radiology 1978; 129:409 – 17.
4. Lakeman F.D., Whitley R.J. et al : Diagnosis of Herpes simplex encephalitis: Application of PCR to CSF from brain biopsied patient correlation with disease. J. infect disease 1995; 171: 857.


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Jul21
NEWER THERAPEUTIC OPTIONS IN SICKLE CELL DISEASE
INTRODUCTION
Sickle cell disease is an autosomal dominant disorder, sickle haemiglobin is the abnormal haemoglobin  chain glutamin acid is replaced by valine. Sickle haemoglobin has the unique property of forming polymersdeoxygenated state. These polymers deform the RBCS to sickle cell. Formation of polymers depends on the concentration of HbS inside the cell. So small reductions in HbS concentration inside the cell might result in significant clinical benefits. That is the reason why sickle cell trait is clinically silent were the HbS concentration is low. With better understanding of pathophysiology of sickle cell disease and its complications, it treatment has also progressed.

Among the haemolytic anaemias, vasoocclusive features are unique in SCD. Now it is well understood that vasoocclusion and tissue ischaemia in SCD involve not only the polymerization of HbS but also interaction between RBCs, endothelium, leucocytes, platelets and plasma factors. Intracellular polymerization of HbS is decreased by a rise in foetal haemoglobin and there increasing HbF is the most clinically studied approach against sickling. Infections, brain injury, renal disease , pain priapism can now be prevented. Complications from lung injury, surgery and transfusion can be minimized.

Management of SCD
Apart from general measures and treatment for symptomatic relief , now the newer therapeutic agents are directed towards prevent of complications.

THERAPEUTIC STRATEGIES FOR PREVENTION OF COMPLICATIONS
Sickling can be interrupted at several key pathways:
1. HbF Augmentation
Most promising agent in hydroxyurea, a ribonucleotide reductase inhibitor, causes myelosuppressive – induced HbF synthesis, resulting in improved red cell survival and decreased sickling. Hydroxyurea is orally active, effective , safe in short term and beneficial in most patients, in the dose of 10-15mg/kg to a maximum of 35 mg/kg. Before starting hydroxyurea, base line evaluation like blood counts, MCV, HbF concentration and serum chemical values and test for pregnancy ( a contraindication) to be done. Blood counts should be performed every 4-6 weeks intervals, granulocyte count should be at least 2000/mm3 and platelet counts at least 80,000/mm3 before or during treatment. An initial Hb concentration below 5.5 gm% is not a contraindication to treatment with hydroxyurea. Adults with higher TLC and reticulocyte counts and larger treatment associated decreases in these counts tends to have greater increases in HbF production and hence better response to hydroxyurea. Although hydroxyurea lowers pain episodes, pulmonary events and hospitalizations, 40% of treated patients do not respond or have progressive organ failure, the reason for this is yet to be settled.
Clinical advances in treatment of SCD
Clinical Features Interventions
1. Pain • Prevention with hydroxyurea
• Patients controlled analgesic devices
• Newer NSAIDS
2. Infection vaccine • Prophylactic penicillin and pneumococcal
3. Anaemia • Phenotypically matched RBCs
4. Lung injury prevention • Hydroxyurea
• Antibiotics (Macrolides)
• Transfusions
• Screening for pulmonary hypertension
5. Brain Injury prevention • Screening with transcranial Doppler , MRI, neurocognitive testing
6. Renal • ACE inhibitors for preteinuria
• Improved renal transplantation
7. Call bladder disease • Laparoscopic cholecystectomy
8. Surgery / anaesthesia safety • Preoperative transfusion
9. Priapism • Adrenergic agonist
• Antiandrogen therapy
10. Avascular necrosis of hip • Decompression coring procedures
11. Severe disease (recurrent acute chest syndrome, pain crises or CNS disease) • Allogenic BMT (< 16 years)
• Chronic transfusion and /or hydroxyurea
12. Neonatal screening
13. Family counseling


Other drugs which can increase HBF concentration are short chain fatty acids like valproic acid, 2-deoxy- 5 azacytidine , erythropoitein.

Other emerging therapeutic agents
Drug Mechanism Benefits
1. Clotrimazole Inhibits red cell Gardos channel Red-cell rehydration
2. Sulphasalazine Endothelial Activation Antiadhesion therapy
3. Deferiprone Chelete membrane iron Antiadhesion therapy
4. Acenocumarol, heparin Decrease thrombin Antiadhesion therapy
5. Pheresis Decrease HbS Transfusion therapy
6. Allogenic – Haematopoietic stem cell transplantation
7. Genetherapy –
a. Direct gene replacement – Direct delivery of &#61538;- globin gene.
b. Indirect gene therapy – Srythropoitin delivery

2. Antisickling agent (through multiple pathway)
Nitric oxide (NO) is a critical factor in the pathphysiology of SCD and hence a potential treatment option. NO regulates vessel tone , endothelial adhesion, leucocytes and platelet activity, an important factor in ischaemia reperfusion injury and sickle cell induced ischaemia. In SCD, more adhesion molecules are produced due to decreased availability of NO. Oral arginine supplementation induces NO production, reduces red cell sickling by inhibiting the Gardos channel (Calcium activiated K = Channel). Treatment of sickle – cell patients with NO or its precursor L arginine have shown promising antisickling activity with vasodilator properties. NO or arginine supplementation may be synergistic with hydroxyurea and seems to further increase. No release and decrease adhesive molecules.

CONCLUSION:
The need to study new applications of current treatment and to devise new treatments direct at disrupting multiple factors of the pathophysiology of the disease remains most important. New therapeutic options like hydroxyurea. No or L-Arginine, BMT, gene therapy appears promising. While awaiting the new treatments for the underlying disease, several partial problems remains unsolved. For example, how should the acute chest syndrome be managed, which patients should undergo exchange transfusion? How aggressively should be blood pressure be lower to decrease the risk of stroke? Can we better understand the cause of striking variability in sickle cell disease, so that hazardous treatment can be directed to the patients who are most likely to have the worst disease complications?

REFERENCES:
1. Bunn H.F. Pathogenesis and treatment of sickle cell disease. N. Engl J Med 1997; 337:762-9.
2. Steinberg M.H. Management of sickle cell disease. N. Engl j Med 1999;340:1021 – 30.
3. Morris C.R., Kuypers A., Larkin S et al : Arginine therapy : a novel strategy to induce nitric oxide production in sickle cell disease. Br J Haematol 2000; 111-498-500.
4. Vichinsky E . New therapies in sickle cell disease. Lancet 2002; 360: 629-31.


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Jul21
UNCOMMON PRESENTATON OF HYPOGONADISM AND HYPERTENSION IN A CASE OF SICKLE CELL DISEASE- A CASE REPORT
ABSTRACT:
Sickle cell haemoglobinopathy, a common haemolytic disease predominant in Western part of Orissa is a multisytemic disease, with varied manifestation. Through some case of nephropathy has been reported, earlier here we report a case of sickle cell disease (SED who had primary hypogonadism, hypertension and sickle cell Nephropathy. The pathogenesis and management are reviewed,.

KEY WORDS.
Sickle cell disease, primary hypogonadism, hypertension and sickle cell Nephropathy.

INTRODUCTION
Sickle cell haemoglobinopathy occurs due to genetic defect where due to mutation of &#61538; globin the 6th amino acid is changed from Glutamic acid to Valine. Due to dexoygenation there occurs structural changes in RBC Clinically the disorder manifests as chronic haemolysis repeated infection growth retardation and sickle cell crisis. The crisis includes alpastic crisis haemolytic crisis sequestration crisis and vasoocculsive crisis. Renal complications are encountered in some cases where the patient presents with haematuria proteinuria, renal insufficiency.

CASE REPORT
A 21 years male was admitted to this hospital in July 2005 with history of fever and jaundice for 5 days generalized pruritus for 4 days and decreased uriniation for 4 days. He had gradual diminished of vision of right eye since 5 years. He had taken Blod transfusion 2 months back at local hospital. On enquiry it was found that another brother who had sickle cell disease died 3 years back, due to vasoocculsive crisis. Both parents were found to be sickle cell trait. The patient had normal milestones of development but there was retarded development of secondary sexual characters and gyaecomastia since last 4 years (Fig.1.2)

On examination the patient had severe pallor and icterus, Blood pressure was 160/90 mmHg in both upper limbs. Pulse rate –110/min regular Temperature 100.20F respiration rate 18/minute. Per abdominal examination revealed moderate hepatomegaly and moderate spelenomegaly. He had bilateral gynaecomastia with sparse public and axillay hairs and facial hair. Both the testis volume were reduced (2.5 to 3 cm) soft with normal testicular sensations. Other systemic examinations including higher intellectual function were normal.

The laboratory examination showed:-
Hb:- 6.6% TLC- 8400/mm3, D/C –N 68 E 2L 30 M0 B 0
Serum Billrubin – Total 21 mg/dl
Direct 19 mg/dl.
S.G. O.T - 58IU/L
S.G. P.T - 57 IU/L
S. Alk Phospatase- 338IU/L
• Hb electrophosis showed SS band.
• Urine analysis showed – Albumin (++) with granular cast and RB Ci 30- 40/HPF and 24 hour urine protein was 300mg/in 24 hour with urine output- 2 Litres.
• Serum Zn- 7.5 (11.5-18..5 &#61549;m&#61553;l/L)
• Untrasonogram of abdomen showed moderate hepatomegaly, spelnomegaly (18cm) with coarse echotexture with spotty calcification. Both kidneys were normal size(11.0cm x 4.5cm) with diminished corticomeduallry differentiation.
• Chest x-ray and skull X- ray were normal.
• Foundscopy revealed papilloedema (Rt eye) with Grade II hypertensive retinopathy. Visual acuity was 6/60 in right eye and 6/9 in Left eye.
• Fasting lipid profile showed TC-109mg%, HDL-25mg% , LDL-50mg% , TG-376mg%, VLDL-75.30mg% , 212.86ngm/dL (270-1070mg/dl)
• Hormonal assay showed Testosterone –FSH – 8.41 IU/ml, LH17.97IU/Ml, Prolactin –5.45ngm/ml, TSH-3.79&#61549;IU/ML, (0.5-4.7&#61549;U/ml) 2.72U/ml) (1.6-23.0 ngm/ml).
• Kidney biopsy showed features of focal segmental glomerulosclerosis (Fig-3, Fig-4)

Patients was treated with antimalarial (Artesunate) antibiotic (Taxim) Pentoxyphylline, folic acid arginine Antihypertensive- Imandipril-10mg (ACE inhibitor) was started and responded well with normalization of BP. After 15 days of treatment the BP was controlled at 120/80 mm Hg, with reduction of Proteinuria. His serum bilirubin came down to 4.6mg/dl (total) and 3.8mg/dl (direct). The patient was discharged.

On subsequent follow up (after 45 days of discharge) 24 hours urine protein –25mg/24 hours, Urine output 2.5 Litres, BP was 120/70.

DISCUSSION:
The gonadal dysfunction as noted in sickle cell disease most often is attributed to primary gonadal failure. Levels of LH are usually increased in sickle cell disease. changes in FSH are usually inconsistent . Testosterone levels are almost always low in male adolescents and adults with sickle cell disease & these levels may respond poorly to GnRH stimulation.

Extreme delay in secondary sexual character is usually confined to males. Testicular size and volume are reduced and testicular histology showed immaturity of seminiferus tubules and replacement by hyaline materials secondary sexual character such as bearded growth, public and axilary hair are retarded.

The determinant of this type of growth may be chronic anemia patients with higher fetal hemoglobin have normal epiphyseal closures. Zinc level are lower in patient with sickle cell disease and studies have shown that zinc supplementation increased growth of body hair, increased testosterone levels and improved testosterone response to LHRH.

Sickle cell nephropathy in the form of glomerular disease occurs in 15 to 30% of sickle cell disease. Usually 15-30% patients develop proteinuria in the first 3 decades. The pathology is usually focal segmental glomerulosclerosis chronic renal failure can be predicted by presence of worsening anaemia, proteinuria, nephritic syndrome and hypertension. ACE inhibitors and ARB retard the progression of renal disease by lowering systemic & glomeruocapillary hypertension.

Hypoxia of renal medulla may also cause papillary necrosis. Coinheritance of microdeletion in &#61537; gene appear to protect against development of nephropathy. Cortical infarcts can cause persistent haematuria, pipiallry infects occurs in 50% of patients with sickle cell trait. Painless gross haematuria occurs with higher frequency in sickle cell trait than sickle cell disease.

Ultrasound examination may reversal a focal or diffuse increased echogenecity which is predominant in sickle cell disease. In the medulla renal tubules and vasarecta involvement can occur. Tubular changes results in atrophy dilatation, proteinacous cast and the so called thyroidization of renal medulla also occur.

In sickle cell disease the GFR is markedly elevated in young patients but decreases with age. As age increases the effective renal blood flow. effective plasma renal flow are decreased. Increased GFR, ERRF in sickle cell disease is usually due to increased synthesis of prostaglandins in early part which decrease in later life.

CONCLUSION
Sickle cell disease is a fairly common disease in this belt of India but usually the focus is directed towards managing vasoocclusive crisis.

But proteinuria, hypertension are the harbinger of sickle cell nephropathy and will respond to ACE inhibitors and ARB. The hypogonadism may be treated in early life by good nutrition, prevention of anaemia and zinc supplementation.


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Jul21
ASSOCIATION OF PLEURAL EFFUSION (LEFT) WITH PANCREATIC PSEUDOCYST
ABSTRACT:
We report a relatively uncommon association of massive pleural effusion (left) with pancreatic pseudocyst in an adult male patient. The pathophysiology, clinical features diagnosis and management of this conditions are reviewed. (The Ind. Pract 2004; 57(8): 553-554).

Key Words: Pancreatic Pseudocyst, Pleural Effusion

INTRODUCTION
Pseudocysta are localized collections of panecreatic secretions that lack and epithelial lining and persist for more than 4 weeks. In the past pseudocysts were detected. indirectly by clinical suspicion, appearance of a palpable abdominal mass and from barium contrast studies that demonstrated a mass. The advent of pancreatic imaging by ultrasonography and CT Scan has lead to the realization that pseudocysts appear in 10% patients with acute pancreatitis.

A variety of clinical and radiographic finding have been associated wit pancreatitis and pleural effusion is one of them. pleural effusion may be bilateral, confined to left side or rarely right sided and may be massive.

CASE REPORT
A 50 year old male patient admitted with history of chest pain for 1 month, swelling of abdmen with upper abdominal pain for 1 month, loss of appetite with nausea for 15 days and dyspnoea for last 3 days. Six months prior to admission he was provisionally diagnosed to be a case of pulomonary tuberculosis with left sided pleural effusion and was on treatment with ATT (4 drugs) for 6 months without any clinical improvement. He is not a known case of DM, HTN, SCD. No history of intake of other drugs. He is a chronic alcoholic for last 20 years.

On examination the patients was of average built with mild pallor, no icterus, no lymphadenopathy, with a pulse rate of 76 per minute, regular BP=118/80 mmHg. Cardiavascular system examination revealed apex beat Rt. 5th ICS. Chest examination revealed trachea shifted to right side. on left side reduced movement , stony dull percussion note, vocal response absent, breath sound diminished. Per abdomen examination revealed mild hepatomegaly with a firm intra abdominal swelling palpable in the middle left upper abdominal region, non tender with irregular margin.

INVESTIGATIONS
Hb = 8.6gm%
TLC = 8000/mm3
DC =N-60% , E-4%, L-36%
ESR =25mm 1st hr
FBS = 92mg%
Urine =NAD
S. urea = 38mg%
S. Creatinine = 1.1 mg%
Na+ = 135m.mol/L
K+ = 3.4 m.mol/L

Pleural fluid analysis revealed , coffee coloured, haemorrhage fluid with TLC could 700 mm3 mostly mestothelial cells mixed with cellular elements of blood. No malignant cells seen. Biochemical study revealed glucose- 60mg% protein – 1.6mg%. LDH- 2280IU/L Amylase- 30 IU/L.

Chest X- ray (PA view0 reveals massive pleural effusion (lt) with trachea shifted to rt.side. USG abdomen and pelvis reveals head of pancreas normally seen but the body and tail could not be visualized. A large cystic lesion of 15cm x 12cm with echogenicity seen with left sided pleural effusion.

The patient was diagnosed as a case of pancreatic pseudocyst with left sided pleural effusion due to acute pancreatitis probably alcohol induced. Pleural tapping was done and about 3000ml of haemorrhagic fluid was drawn out. He was put on of loxacin. valdecoxib, haematinics and other supportive treatment. The patient showed marked improvement during hospital stay and planned for surgical management for the existing pseudocyst.


DISCUSSION

Pancreatic pseudysts are collections of tissues, fluid debris enzymes and blood which develop over a period of 4 weeks after the onset of acute pancreatitis and constitute about 10% of patients of acute pancreatitis. It is encountered most frequently with alcoholic panaceatitis. Pseudocysts associated with pleural effusion are most common on the left but may be bilateral and rarely limited to right pleural space (Gumaste Singh, Dave et a, 1992) it is assumed to be a new prognotic parameters for acute pancreatitis (Lankisch Droge, Becher et al1994).

Psyeuodycysts lack epithelial lining and disruption of the pancreatic ductal system is common. Approximatelty 85% are located in the body or tail of pancreas and 15% in the head. If the pancreatic duct disruption is posterior, an internal fistula may be develop between the pancreatic duct and the pleural space producing a pleural effusion which is usually left sided and often massive. Conservative therapy is indicated if the pseudocyst is shrinking evidenced by serial ultrasound and minimal symptoms pseudocysts (every 3 to 6 months) Long acting somatostatin anagogic octreotide which inhibits pancreatic secretion is useful in cases of pancreatic ascetics with pleural effusion.

Pseudocyst with communicating duct if strictured require internal surgical or endoscopic drainage. Transgastric percutaneous approach is favoured. Associated massive left sided pleural effusion often required thoracentesis or chest tube drainage. A disrupted pancreatic duct can be treated by stenting.

CONCLUSION

Association of the left sided massive pleural effusion with pancreatic pseudocyst is relatively uncommon. However, additional studies are needed to substantiate these results.

REFERENCES
1. Gumaste V., Singh, V., Dave P. Significance of pleural effusion in patients with acute pancreatitis. Am J. Gastroenterilogy 1992; 87: 871.
2. Lankisch P.,G. Droge M and Becher R. Pleural effusion : A new negative prognostic parameter for acute pancreatitis. Am J Gateroesterol 1994; 89: 1849.
3. Slesinger and Fordtran’s Gastrointestinal and liver disease (6th edn) vol1 Sleisenger Feldman Scharshmidt Klein (W.B Saunders Co) 815:826:836.
4. TB of Gastroenterology (Vol-II) 2nd Edn Year 1995 (T. Yamada. J.B. Lippincott Co. Philadelphia ) page 2078-84.
5. Harrisons principles of Int. Medicine 15th Edn Vol 2 year 2001: Page-1798.


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Jul21
HYPOKALEMIC PERIODIC PALSY IN A CASE OF SITUS INVERSUS WITH DEXTROCRDIA- A RARE ASSOCIATION
ABSTRACT:
Hypokalemic periodic palsy a common hereditary disorder encountered in clinical practice. Classical history physical findings, laboratory diagnosis and response to treatment establish the disease. Association of another hereditary cardiac disease (Situs in versus with Dextrocardia) is recorded for the first time.

Key words: Hypokalemic, Dextrocardia.

INTRODUCTION
Dextrocardia in situs inverses is one of the earliest known congenital alterations of the heart described in 1943 by the anatomist surgeon. Marco Aurelio Severino. There are three clinically important cardiac malpositions2 i) visceroatrial situs inverses with Dextrocardia (complete situs inverses) ii) Vesceroatrial situs solitorious with right –side heart and apex iii) visceroatrial situs inverses with left sided heart and apex. These cardiac malpositions are associated with various cardiac and non cardiac anatomical detected by chest radiography and surface ECG. Metabolic diseases, epically hereditary diseases like hypokalemic periodic palsy, which is due to abnormality in K+ channel, can alter the presentation of dextrocardia.

CASE REPORT
A 37 yr Hindu male presented with weakness of both upper and lower limbs for 5 days slurring of speech for 2 days and mild unable to walk from the first day. This was marked at noon when he was taking rest, after lunch. There was no history of trauma convulsion, headache, or root pain. One yr before he surfaces from same type of episodic illness. He was married and had two children. No family members suffered from this type of illness. On the day of presentation, he was apyrexial. Para nasal sinuses were tender. His higher functions were normal. Power in lower limbs and upper limbs were decreased (2/5). Planter was B/L flexor. Reflexes of both UL and LL were bilaterally diminished. His cranial nerves were normal except mild slurring of speech. Chest examination revealed respiratory rate 24/min and chest expansion <4cm and crepitations over bilateral infrascapular area.
On C.V.S examination, apex was present at right 4th I.C.S on MCL instead of left side. All the cardiac sounds were prominent on right side. No murmur of extra heart sounds detected. No abnormally of pulse or B.P. was noted. Fundic gas on percussion was present in the right side and liver dullness on left side. A structure was felt at Rt. Hypochondrium probably spleen.

On that day, Na+ and K+ were detected as 127 mmol/L respectively Sputum for AFB was sent for 3 consecutive days, which was negative. Other routine investigations were within limits. Chest X- ray showed right-sided cardiac shadow with left sided hepatic shadow.

ECG was done on the day of admission of which P were was inverted in lead I, aVR, aVL; QRS axis was+1500 and –ve in lead I, aVL and all chest leads . QT interval normal TU wave was seen in lead I, III, & aVL & U wave in lead II. Nerve conduction study was normal.

On the basis of ECG and laboratory finding the patients was diagnosed as hypokalemic palsy and treated with oral as well as parenteral Potassium Chloride (KCL) and muscle power improved within 24 hr with no residual neurological deficits. Same day, abdominal USG and 2D ECHO, were done, which showed situs inversus with dextrocardia. After KCL treatment, k-level became normal and patient was discharged after recovery.

DISCUSSION
From 1937 hypokalmeic periodic palsy is a well-known disease3. Usually pattern of inheritance is autosomal dominant with reduced penetrance in women4. Above mentioned male patient who presented with acute onset LMN type of quadriparesis with mild respitory and bulbar muscle involvement after an episode of fever give suspicion about AIDP, through repeated attack of same type of illnmess give suspicion about hypokalemic periodic palsy. Low K+ level normal nerve conduction study and no sensory involvement established the diagnosis and justified by recovery with oral and i.v KCL supplementation . Through hypokalamic periodic palsy may present with ventricular dysarrhythmia and dysmorphic features (Anderson’s syndrome)5 reported earlier dextrocardia association is not described till now. Clinical examination, ECG and X- ray chest PA. view of the patient reveals Dextrocardia with situs inversus, crepitations over the chest and sinus tenderness may be the sign of another two of three cardinal features of Katagener’s trid6, which is autosomal recessive disorder. Through situs inversus is usually associated wit male infertility, this patient is dertile with two children7.

CONCLUSION
Hypokalemic periodic palsy with dextrocardia with situs inversus may be a coincidence or rare association reported first time.

REFERENCES:
1. Brown, J.W Congential Heat Disease. London St. Apless Press Ltd, 1950.
2. Van Pragh. R. Winburgs, et al Malposition of the heart in Moss. A.J. Alams et al (Eds) Heart disease in infants, children and adolescents. 4th edition Baltimore. The Willams & Wikins Company, 1989.
3. Talboot JH Periodic Paralysis : A clinical Syndrome Medicine 20:85, 1994.
4. Fortain B et al: Mapping of hypokalemic periodic paralysis to chromosime 1q3t, q32, Euofan and family nature genet 6:267, 1994.
5. S. Ansone V. Griggs RC, Meolag et al: Anderson’s Syndrome; a distinct periodic paralysis. Ann Neural ; 7: 110 1984.
6. Barnstom W.H. et al; Situs inersus Bronchaactesis and sinusitis; reported of family with 2 cases of Kartagener’s triad pediatrics 6:573, 1950.
7. Afzelius B.A General and Ulterstructural aspects of the immobile cilia syndrome Am of human generic 33:852, 1981.


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Jul21
SNAKE BITE AND ITS MANAGEMENT
INTRODUCTION
The Indian subcontinent is home to more than 230 species of snakes of which some are poisonous. In 4 families of venomous snakes, 6 species are responsible for snakebites & are medically important in India.
They are :-
1.Elapidae. Represented by * Cobras a. King Cobra (Ophiphagushannah)
b. Common Cobra (Naja Naja)
* Krait. (Bungarus ceruleus)
2. Hydrophilidae - Seasnakes.
3. Viperidae - Russel viper/Saw scaled vipers.
4. Atractasipidae.
Here the epidemiology, pathogenesis, clinical features and managements are discussed.
EPIDEMIOLOGY
It is widely agreed that India contributes the largest share to the annual worldwide mortality due to snake bite. Figures of mortality range from 15000,to 40,000/year in India. Hospital records the sole source of most snakebite likely to over represent the more seriously envenomed patients. As in developing countries like India 80% of victims first consult traditional healers, so population survey gives most accurate picture of diagnosis than hospital record. First of all it was SWAROOP STUDY which reported about 200,000 bites/yr and 15,000 deaths as far as back in 1954. based on epidemiologic survey of 26 villages with a total population of 19,000 in Burdwan Dist. of W.B. HARI et all worked out an annual incidence of 0.16% and mortality of 0.061%. Myanmar has the highest snake bite mortality in the world. Maharastra has highest incidence of snakebites i.e 70bites per 100,000 population/year, with mortality of 2.4/ 100,000 per year. Bengal, Tamilnadu , UP & Kerala, are other states with large no of snake bites. Chippaux study shows marked increased frequency of - illegitimate bite in Developed countries and hazardous bite in developing countries.

Age & Sex
Though all age groups of both sexes are the victims majority are 11-50 years of male suggesting special risk in outdoor activities. Males are victimized twice or thrice than females.

Time & Seasonal variation:-
Maximum incidence between 4.00pm to midnight (varies with outdoor activities). During rainfall & epidemics after floods and natural disaster.
Site of bite:-
Most frequent site of bite – Lowerlimb(2/3rd ) of which 50% occur in feet alone.
Host factors:-
Occupational hazards- for farmers, harder, hunter & fisherman.
Morbidity & mortality:-
Depends upon the species of snake involved as estimated fatal dose of the venom varies with species.
Average Yield/bite Fataldose is much smaller
1.Cobra - 60mg 12mg.
2.Russelviper – 63mg 15mg.
3. Krait – 20mg 6 mg.
4. Saw scaled viper – 13 mg 8 mg.
Severity of Envenoming:-
Depends upon the dose of venom injected, composition & potency of venom, number & depth of bites, age of the victim, site of bite, nature, timing & quality of first aid & medical treatment.

PATHOPHYSIOLOGY OF OPHITOXEMIA:-
Most complex of all poisons are mixture of enzymatic & nonenzymatic compound, nontoxic proteins including carbohydrates & metals.
Enzymes – It is a constitute of 20 different enzymes including phospholipase. A2 B, C, D, hydrolases, phosphatases, proteases, esterase, Acetyl choline esterase, transaminase, hyaluronidase, phosphodiesterase DNAse RNAse etc.

Nonenzymatic compounds are - Neurotoxins
- Haemorrhagins.
Different species have different proportion of most of it. So they are formerly categorized as neurotoxic, haemotoxic, myotoxic but strict categorization is not essential
• Neurotoxins
Cobra – Cobrotoxin & bungarotoxin causes postsynaptic blokage (at moter end plate release of Ach).
Krait – B bungarotoxin causes pre synaptic blockage
Viper – Acetylcholine esterase causes breaksdown of Ach.
• Cardiotoxins
Cobra & Taipan – cardiotoxins causes myocardial depression and cardiac arrythmias.
• Vasculotoxins
Viper – Viper venom – affects coagulation pathways at several points. Activates factors V, IX, X, XII, platelets & protein C & fibrinolysins.
Haemorrahgins – damages endothelium to produce spontaneous bleeding, potentiates platelet aggregation & favours vasodilation.
• Myotoxins
Sea snake - Myotoxins produces muscle necrosis, myoglobinuria, hyperkalaemia.
• Nephrotoxins
Vipers – Indirectly damage renal system and causes prolonged hypotension, hypovolumia and hyperkalaemia/DIC/direct damage/rhabdomyolysis.
• Locally affecting toxins are protease, phoshpolipase 2, polypeptide toxins, hyaluronidase, histamine/brady kinin, hydrolanse
• Proteolysis
(Damages RBC, leucocytes & platelet membranes & vascular endothelium & other membranes.)

Increase Vascular permeability – Local effects, (swelling, edema inflammation, gangrene).

Systemic effects.

(Hypoalbuminemia) (hypotension) (shock)
CLINICAL FEATURES
I. Snake bites with no manifestations:
Confirmed bites with no manifestations – Drybites by poisonous snakes and bite by non poisonous snakes, Large no of studies show that a lot of poisonous bites do not cause symptoms, Banerjee – noted 80% of victims have no evidence of envenomations. Reid also states that over 50% of individual bitten by poisonous snakes escape with hardly any feature of poisoning, Stainly’s 117 out of 200 cases showed envenomation, Lamb states that 30% of cobra bites are superficial.

II. Local manifestations :-
Physiological trauma is the earliest. Local reactions are marked in both families of elapidae and viperadae ( krait is the exception). Local reactions are noted within 6-8 mins but may have onset upto 30min & develop upto 24 hrs. Local pain , with radiation & tenderness and the development of small reddish wheal are first to occur followed by oedema, swelling & appearance of bullae progressing rapidly involving trunk. Tingling, numbness over tongue, parasthesia around wound local bleeding including petechial & purpuric rash – more common in viperbites. Regional lymphadenopathy is an early & reliable sign. Intercompartmental syndrome- occur in 10% of cases. Necrosis of skin, subcutaneous tissue & muscle causes increased intercompartmental pressure which leads to pain & anasthesia on stretching of intercompartmental muscles. Severe pain, absence of arterial pulses and cold segment of limbs is due to thrombosis of major arteries which may lead to dry gangrene. All the above features of local reactions are evident in elapidae but the gangrene is mostly wet gangrene. In rare instances patients may have – Raynaud’s phenomenon/ secondary infection/ tetanus/ gas gangrene.
III. Systemic Menisfestations:
The most common and earliest symptom following snake bite is fright of unpleasant & rapid death. Victim attempts flight which unfortunately results in enhanced systematic absorption of venom leading to psychological shock & even death . Fear may cause transient pallor, sweating & vomiting.
Time of onset of systemic poisoning in cobra – 5 min to 10 hrs, Viper – 20 min to several hrs and Sea snake – almost always within 2 hrs.
Systemic manifestations depend predominantly on the constituents of the venom of that particular species as neurotoxin (cobras & kraits) haemorrhagin(vipers) myotoxin(sea snake), but strict categorization is not valid.
a) Neurotoxic features
Usually within 6 hrs but may be delayed. Symptoms are usually preceded by preparalytic syndromes which includes vomiting, blurred vision, drowsiness , heaviness of head, tingling sensation of mouth. Paralysis first appears as bilateral ptosis followed by bilateral opthalmoplegia, followed by paralysis of muscles of palate jaw, tongue , larynx , neck & muscles of deglutition . Muscles innervated by cranial nerves are involved earlier. Pupils react to light till terminal stage. Reflexes are not affected usually & preserved till late stages. Muscles of diaphragm are involves late which accounts for terminal respiratory paralysis. Onset of coma is variable ( may progress to coma in 2hrs).

b) Cardiotoxic features:-
Include tachycardia, hypotension, & ECG changes. 25% of viperbite include rate/rhythm/bloodpressure fluctuation. Sudden cardiac arrests may occur due to dyselectrolytemia. Though nondyselectrolytemia MI has also been seen.
c) Haemostatic abnormalities:-
One case of nonbacterial thrombotic endocarditis-reported from, PGI Chandigarh. Bleeding from the punctured wound is the earliest feature, Blood do not coagulate due to consumption coagulopathy &haemorrhagins produce widespread bleeding detected as bleeding gum, nose, GIT (haematemesis & melaena), Urinary bladder (haematuria). Consequent to bleeding hypotension & shock occurs. Intracerebral haemorrhage may occur. Subarachnoid haemorrhage is reported in 5 in 200 cases of Saini’s series in Jammu,(most were elderly).
d) Nephrotoxicity:-
In a series of study of Clarke out of 40 viper bites renal failure was detected in 3. The extent of renal abnormalities is correlated with the amount of coagulation defect . However renal defect persisted for several days after coagulation defect normalized, suggesting that multiple factors are involved in venom induced ARF.
e) Hypotension syndromes :-
Due to increased capillary permeability – menifested by serous effusions/ pulmonary edema/ haemoconcentration/hypoalbuminemia/shock.
f) Pregnency outcomes:-
Almost all pregnant abort or present with APH/PPH.
g) Rare outcomes-
Hypopitutarism, bilateral thalamichaematoma, hysteric paralysis.
LABORATORY DIAGNOSIS:-
• History- Patient usually gives history of snakebite but it may be absent in kraitbite (painless). Although fangmarks are essential fatal envenoming do occur without identifiable marks.
• Cell counts – Neutrophillic Leucolytosis
- Anaemia
- Thrombocytopenia
- Haematocrit – Initially ( haemoconcentration), Later ( haemolysis).
• Coagulation profile - Prolonged clotting time
- Prolonged prothrombin time.
- Fibrin Degradation products ( >80 mg/dl).

• Simple bedside test
(1) Tourniquet test – Torniquet pressure of 100 – 120 mm of Hg is applied for 5 minutes – (+ve) if >5purpuric spots.
(2) Whole blood clotting test :- 5ml of blood taken in clean, dry test tube- undisturbed for 20 min – seen for clotting.
(3) Clot quality observation test (Clot retraction test):- seen for clotting after one hour

• Urine Analysis
All snake bite patients should be advised to evacuate bladder at first aid & urine examined for microscopic haematuria. It could also reveal proteinuria, haemoglobinuria or myoglobinuria.
• Features of Azotemia S.Urea , S.creatinire may be raised.
• Metabolic parameters:- Hyperkalaemia, Hypoxemia, Respiratory acidosis may occur
• Myotoxicity is evidenced by – Raised Sr.CPK, & transaminase .
• ECG shows – Nonspecific alteration in rate, rhythm, predominently bradycardia, menifestation of hyperkalemia.
• X-ray chest – To rule out pulmonary edema/Infarction/bronchopneumonia/pleural effusion
• CT scan - May be required if suspision of Intracerebral bleeding,
• Immunodiagnosis

Detection of venom antigens in bodyfluids –
Used for - Pathophysiology
- Assessment of first aid
- Antivenom dose monitoring.
ELISA test – (venom detection kits) - Highly sensitive but not specific.


MANAGEMENT
1. First aid:-
Reassurance (to flight & fright response), Immobilisation of bitten limb, No tampering of the wound is best (Reid). Aim should be to transfer the patient to nearest hospital as quickly as passively as comfortably as possible.

Controversial first aid methods which are :-
• Local incision, excision of bitten skin , cauterization, amputation of digits
It has been proved from animal studies that all these methods do not decrease systemic envenomation, rather potentates bleeding introduces infection damage tissues.
• Suction by mouth as shown in Indian cinema has been rejected by its questionable efficacy while some advocate large amount of venom can be aspirated by this method if approached within seconds.
• Introduction of chemicals are worthless ( Nowhere recommended in any textbooks& therapeutics, rather rejected by Mansoon)

2. Use of tourniquets, compressionpads, bandages (controversial):-
Manson – Tight tourniquets have been responsible for terrible morbidity & mortality in snake bite victims & should not be used .
Sautherland (Australia)- advocated a pressure immobilization method by crepe bandaging proved effective in limiting absorption of venom ( applies p.of 55of hg). It is just tightly as sprained ankle starting from toes & fingers & incorporating a splint. It should be binded so tightly that only lymphatic circulation is obliterated not arterial. One finger should be introducible between the affected part & tourniquet. Use of tourniquets may be dangerous as they can cause gangrene, fibrinolysis, bleeding from occluded limbs, peripheral nerve palsy, compartmental ischaemia , intensification of local reaction. So general consensus in Western countries is to use crepebandage & splints in Elapidae and Sea snakes bites and to be avoided in Viperbites, which are responsible of intense local reactions. Clinical trials are needed to prove the efficacy of tourniquets & Compression bandage. The patient should be transferred in Lt. Lateral decubitus position to prevent aspiration.
3. Drugs :-
Reid advocated pain relief with placebo was as effective as NSAIDS. Gellert- experienced that codeine sulfate should be given to calm the patient & to reduce autonomic hyperactivity. Vomiting – can be treated with chlorphromazine ( 25-50mg IV infusion.) Others symptoms like syncope , shock, angioedema if supervene 0.1% adrenaline S/C can be given as first aid .


4. Specific Therapy :-
A. ANTIVENOM :-
Decision – In the management of snakebite, the most important clinical decision is whether to give antivenom therapy. For only a minority of snakebite patient need it. It may produce severe reactions & it is expensive & often in short supply.
Preparation:- They are prepared by immunizing horses with venom of poisonous snakes & extracting serum & purifying it . They may be species specific monovalent form/ poly valent form . Supplied as dry powder & reconstituted with DW or NS.
INDIA – C.R.I. Kasaulli – Antivenom against 4 medically important species are available.
Hopkins institute Pune – Against 30 species are available.

INDICATIONS OF ANTIVENOM TREATMENTS
a) Systemic envenoming
Neurotoxicity (ptosis, opthalmoplegia), incoagulable blood indicating consumption coagulopathy / DIC, spontaneous systemic bleeding ( from gingival sulci , nose), hypotension ( shock), generalised rhabdomyolysis. ( stiff tender painful muscles darkurine, myoglobinuria), impaired consciousness.
b) Severe local envenoming
Extensive local swelling ( > ½ of bitten limb), rapidly evolving local swelling, bites on fingers and toes, wider range of indication are prescribed in wealthy countries.
Contraindications Atopic patients & those previously had reaction with equine antiserum.
Prediction of antivenom reaction :- Hypersensitivity testing by intradermal or S.C. injection of diluted antivenom have no predictive value for early and late antivenom reactions. However these tests delay the start of treatment & are not without risk.
Prevention of antivenom reactions:-
Desert et all advocated in their trial that significant reduction in ASV reactions (from 12.5 to 30%) if the patients are given adrenaline subcutaneously (0.1% of adrenaline).
It is a dictum that it is never too late to give antivenom as long as signs of venom persists (it can be given from 2 days of seasnake bite to many days after viperbite proved by Saini’s study) .

Average requirements of dose in various studies:-
1. Bhat(1974)[Jammu] Intermittent Bolus Dose
Initial – 20 ml
Repeat – 20 ml every 4to 6 hrs till clotting time (CT) normal Total Dose
80ml-in mild
100 ml – moderate
250 ml – severe.
2. Thomas & Jacob (1985) [Kerala] Continuous IV infusion 153 ml – Traditional
79 ml – modified
3. JIPMER (1994)
( Pondichery) Local envenomation :_
Systemic envenomation:-
Initial – mild to moderate
Severe defect –
Repeatdose - 50 ml Iv bolus (single)

100 ml
50-200ml
50 ml every 4 to 6 hrs till CT - normal
4. Tariang et al (1996)
( CMC Vellore)
High Dose ( 31 pts)
2 vials IV infusion over 2hrs followed by 2 vials over 4hrs 4hrly till CT becomes normal then 2vials infusion over 24hrs.
Total –89 ml Low Dose(29pts)
2vias over 1hr followed by 1vial every 4 hrly IV infusion over 24hr


Total – 47ml
5. Das et al (1999)
(JIPMER)
Despite of high dose 44.4% developed ARF and dialysis required. Total – 183.3ml(4patient)
70 ml - Bolus
30 ml over 6 hr/6hrly till CT becomes normal 153.8 ml(5pts)
30 ml bolus
30ml over 6 hr/6hrly till CT becomes normal

Suggestive tentative schedule:-
• Over various parts of the country recommended doses are:-
Viper – Initial dose – 20 to 100 ml
Repeat dose – 20 to 50 ml every (4-6) hr till CT is normal
Recurrence of coagulation defect – 20 to 50 ml.
Cobra/Krait – Initial dose – 200 ml preferred (100 ml effective)
Repeat dose – (50-100)ml 4 to 6 hrly - Until neurotropic sign disappear
King Cobra – (100-150) ml Monospecific ASV

Fab based Antivenom alt. to IgG

Dart et al 99 (1) It largely reduces the antivenom reaction
(2) Effectively reverses coagulation abnormalities.
However it requires repeated doses as ½ life is<12 hrs

Antivenom Reactions
Clinical features Treatment
1. Early anaphylactic reaction :-
(10 min –3 hrs) Itching, Utricaria, Vomiting, fever tachycardia
40% develop systemic hypotension bronchospasm, angioedema ( socarefull watch) -Adrenaline(0.5ml-1ml 1:1000/S.C)

Chlorpromazin 10 mg IV
(&#61613; Incidence with &#61613;dose incidence with refined antivenom and more in IM > Iv)
2. Pyrogenic reaction (1-2)hrs Fever, rigor vasodilatation Hypotension. Paracetamol(15 mg /kg)
3.Serum Sickness (7days )
(5-24 days) Fever itching arthralgia (TMJ) particular swelling mononeuritis plultiplex Albuminuria/ encephalopathy Chlorpromazin PM 2mg/4tim x5 days
Prednisolone
(5mg/4times x(5-7)days)

B. HYPOTENSION SHOCK – Fresh blood is ideal
- Ionotropic support
- I.V Hydrocortisone ( in delayed hypotension )
C. NEUROTOXICITY
• Bulbar, respiratory paralysis – cuffed endotracheal intubation / tracheostomy.
• Complete respiratory paralysis – Mechanical ventilation .
• Anticholine esterase – like Neostigmine produces a rapid useful improvement in neuromuscular transmission. Worth giving after Tensilion test
• Neostigmine – (50-100&#61549;g)/kg and atropine(0.06mg)4hrly or by continuous infusion .
D. RENAL FAILURE:
Cautious rehydration, Diureties if renal failure, Haemodialysis/ Peritoneal dialysis.
E. LOCAL INFECTION:
Tetanus toxoid, Antibiotics to prevent infection at the site of bite (chloramphenicol, erythromycin, penicillin) Bullae should be left as such, limb should not be elevated, Necrotic tissue debridgement should be done as soon as possible & denuded area should be covered with split skin graft.

F. INTERCOMPARTMENTAL SYNDROME:
Fasciotomy if I.C.P > 45mm Hg, Only after correction of coagulopathy
G. SNAKEVENOM OPTHALMIA:
Immediate wash with normal saline, Exclude corneal abrasion by slit lamp examination installation of local Antibiotic/Adrenalin to relieve pain.
H. HAEMOSTATIC DISTURBANCES:
After neutralising venom procoagulant by specific antivenom restoration of coagulability & platelet function may be achieved by giving fresh blood, fresh frozen plasma, cryoprecipitate or platelet concentrates. Heparin producing disastrous results must be avoided.
I. DRUGS:
Costicosteroids , Antitibrinolytics, Antihistaminics, trypsin and other herbal medicine have no proved efficacy rather harmful.
CLINICAL FOCUS
• As a tropical, agricultural and developing country snake bite is common in India . Few snakes are poisonous.
• Incidence is more is males with seasonal variation.
• The average yield/bite is much higher than fatal dose.
• Severity of envenoming depends on various factors.
• The venom is a complex combination of which neurotoxins haemorrhagin and myotoxins are lethal to human.
• The clinical presentation varies from local reaction (various grades) to variety of systemic manifestations.
• Diagnosis depends on history, simple bed side clot retraction test, urine analysis and other parameters depends on systemic involvement.
• Treatment protocol includes simple first aid, torniquet (controversial) symptomatic and specific antivenom (ASV) therapy.
• The antivenum has many reactions but still life saving. The dosage schedule varies in different studies and in different species of snakes.
REFERENCES
1. Mansons Textbook of Tropical diseases
2. Oxfont textbook of Medicine. Page 1; 925 – 1:935.
3. Harrisons principle of Internal medicine. Page 16th Edn 2593-2595.
4. API text book of medicine 2003, 7th Edition, 1279 – 1282.
5. www. pubmed. Com.
6. www.medfinder.com.
7. New England Jaurnal of Medicine.


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Jul21
RECENT ADVANCES OF MYASTHENIA GRAVIS
INTRODUCTION
‘MG’ the commonest neuromuscular junction (NMJ) disorder caused by Auto antibodies against the Nicotinic AChRs on post synaptic membrane (PSM) and characterized by weakness and fatiguability of voluntary muscles.
• Being very disabling often fatal, a relatively obscure condition is now best characterized and understood autoimmune disorder with greatly improved understanding in pathogenesis/ immunology/ Molecular Biology over last 3 decades.
• The practical mortality rate is ‘o’ with newer advancements.
CLASSIFICATION
Based upon onset of age / Anti Ach R antibodies/severity /etiology.
1. Age of onset:
• Transient Neonatal MG (10-20%). Due to passage of Anti AchR – Abs through placenta to newborn baby. Presents with Hypotonia , Resp.difficulty in 1st few hours of life. Symptoms disappears within 1-3 hours . May require temporary supports , pyridostigmine.
• Adult Autoimmune MG
2. Presence or absence of Anti AChR – Abs :
• Seropositive MG: Commonest acquired autoimmune MG. 85% general MG, 50-60% ocular MG
• Seronegative SNMG (10-20%): No Anti AchR – Abs detectable by RIA, Involve antibodies against one or more components of NMJ (not detectable by current Anti AchR – RIA), One subgroup (40%) of SNMG contains anti MuSK Abs , humoral factors IgG, Non IgG (Possibly IgM) antibodies, which reversibly & indirectly inhibits AchR function.

3. Severity
A. Modified Osserman Scale:
a. Ocular myasthenia
b. Mild generalized - Symptoms sparing oculopharygeal muscles
c. Moderate generalized- Weakness with mild to moderate oropharyngeal symptoms
d. Severe - Disability (generalized) including oropharyngeal/ Respiratory muscles
e. Myasthenic crisis
B. Modified form by American Committee of mg foundation
i. Any ocular weakness (may have weakness of eye closure with all other muscle strength – normal)
ii. Mild weakness other than ocular muscles… &#61617; ocular muscle weakness of any severity
IIa – Prominent limb/axial involvement,
IIb – Predominant oropharyngeal / Respiratory involvement
iii. Moderate weakness other than OM, may have ocular weakness
IIIa – Predominant limb/Axial involvement
IIIb – Predominant oropharyngeal /Respiratory involvement
iv. Severe Weakness other than OM, May have ocular weakness
IVa – Predominant limb/Axial involvement
IVb – Predominant oropharyngeal /Respiratory involvement
v. Intubation with or without mechanical ventilation
(Except when patient kept during post operative management)
4. Etiology
a) Acquired autoimmune MG
b) Transient Neonatal MG
c) Drug induced Mg – ‘D Penicillamine’
d) Congenetal Myasthenic syndrome – exacerbated with curare /Aminoglycosides/quinine /procainamide /Ca+2 blocker
NORMAL ANATOMY & PHYSIOLOGY OF NMJ
Role of NMJ:
• Amplification of weak N. impulse to strong – capable of producing muscle contraction
• Components: (a) Presynaptic (b) Synaptic(c) Post Synaptic
Presynaptic :
Arrival of N. impulse
&#61615;
Stimulus – Secretion coupling
&#61615;
Release of 150 – 200 quanta (each with 8000-13000 AChmol)
Exocytosis – help in relasing ACh

Pinocytosis – Recapturing of PSM, vesicles are remade, being repleted with ACh.
• ‘ACh – release sites’ – located opposite to the peaks of folds of PSM where ‘AchR” are clustered in high concentration.
Synaptic Cleft:
Space – 70nm wide, length equal to pre-synaptic membrane, Communicates to extracellular space , No. lateral boundary. Primary cleft: Space separating pre & post synaptic membrane. Secondary cleft: Space between junctional fold of synaptic membrane. ‘AchE’ highly concentrated in secondary cleft . ‘ACh’ released into the space before it acts on ‘AchR’ and hydrolysed by ‘AchE’ to terminate NMT, so that muscle fibre can be stimulated again. ACHE inhibitors increase availability of ‘Achs’ and increases NMT in “MG”
Post synaptic:
Surface of muscle cell membrane, present itself with junctional folds having slender (Stalk) & terminal expansion (Peak). ‘AchRs’ mostly concentrated in ‘Peaks of these folds.
AchReceptor & Its structure
A glycoprotein with five subunits around a central channel. Subunits are : Two ‘&#61537;’ , one ‘&#61538;’ , one ‘&#61540;’ one ‘&#61646;’/’&#61543;’. ‘&#61646;’ subunit is replaced by ‘&#61543;’ in an immature /denervated muscle. In resting stage ion channels remain closed.
NORMAL PHYSIOLOGY









Once &#61537;-subunits occupied by ACh&#61614; slight twisting of AchR like Chineese purse &#61614; opening of ion channel &#61614; rapid entry of Na+ ions into interior of muscle cells &#61614; partial depolarization of PSM at end plate region &#61614; generation of Excitatory Post Synaptic Potential (EPSP).
** - When number of opening channels reaches threshold &#61614; self propagating action potential triggers muscle contraction.
** - ‘Synaptic Run Down’ (SRD) – progressive decreases in ACh release on repeated Nerve Stimulation (NS).
** ‘Safety Factor’ (SF) – Higher amplitude of End Plate Potential (EPP) than potential required to trigger Muscle Action Potential (MAP).
NMJ abnormality in “MG”:
Reduced SF with normal SRD &#61614; progressive decline in muscle power on Repeated Nerve Stimulation (RNS). Fundamental defect: decreased AchRs at Post Synaptic Membrane (PSM) (<1/3rd) . Flattened & simplified Post Synaptic (PS) folds &#61614; Decreased NMT. Production of small EPP &#61614; Failure in triggering &#61614; Weak muscles contraction
Major post synaptic abnormalities:
Decrease in AChRs causing reduction in PSM length. Shortening of synaptic fold due to destruction of terminal expansion. Widening of synaptic cleft by shortening of junctional folds.
IMMUNOPATHOGENESIS IN MG
Evidence in favor of immunoattack:- ‘AChR- abs’ found in 80-90% patients (Lindstrom et al , 1976). Circulating anti ‘AChR- abs’ found in transient Neonatal MG that declines when patient recovers. Passive transfer of IgG to mice produce similar disease (Vincent & Newson, 1985) Plasmapheresis lowers ‘AchR’ level resulting improvement. IgG abs bind to AchR being localized at the crest of PSM folds (Engel et al, 1979). Experimental model of MG can be produced with purified ‘AchR’
MECHANISM OF DESTRUCTION of ‘AchRs’:
Blockade of the active sites of ‘AchR’. Accelerated turn over with alteration in ‘AchR’ with rapid endocytosis & degradation by muscle cells. Antibody and complement mediated Destruction of Junctional folds of PSM (Engel et al, 1977). Serum AchR concentration does not correlate with severity, rather depends upon. (a) Antibody activity – Accelerated degradation, blocking of AchR ability to bind complements. (b) Difference in NMJ – of different patients / of different muscles of same patient.
Immunopathology & seronegative MG
Circulating Abs not detectable by RIA can destroy AchR in culture system. Produce similar illness when transferred to MICE. Few SNMG patients shows abtibody against MUSK (Muscle Specific Kinase) the protein of anchoring & clustering of AChRs at PSM. Interference in anchoring & clustering impair NMT. Other group of SNMG patients shows undetectable ‘antibodies (abs)’ against other components of NMJ.
Role of T Cells
Thymic ‘T’ cells – more responsive than peripheral blood T cells (Sommer et al, 1990). Thymus contain more ‘B’ cell & produce more abs against ‘AChR’ than control (Scadding et al, 1981). Presence of myeloid cells (Striated /Multinucleated/Muscle like cells) (Vande Velde & Friedman, 1970) having ‘AChR’ on their surface (Kao & Drachman , 1977) surrounded by (CD4+) T cells (Kirchner et al , 1988). Molecular mimicry of myeloid & skeletal muscle AChR & association with immunocompetent cells altogether constitute the important mechanistic hypothesis causing MG.
CLINICAL FEATURES
Presentation: History of cardinal features – ‘weakness & fatiguability’ of muscles on sustained /repeated activity with sudden /gradual onset. Improves after rest. Variation: Diurnal & timely variation. Factors affecting – exertion , hot temperature, infection , emotion, surgery, menstruation, pregnancy, drugs (aminoglycosides, phenytoin). Remission : Rarely complete & permanent. Tendency to long term spontaneous remission & relapse (lasting for weeks). Distribution of weakness (decreased order). Levator palpabrae superioris. Extraocular muscles (initially in 50%, eventually in 90%). Proximal limb muscles (Triceps , deltoid, illospoas). Muscles of facial expression , mastication & speech. Neck extensors. Progression: ocular &#61614; facial &#61614; lower bulbar &#61614; truncal &#61614; limb muscles

SIGNS & SYMPTOMS
Ocular
Presenting symptoms is more than one half of patients. Pupil never involved. Ptosis & diplopia: Initial symptom in 2/3 cases , all develop within 2 years. Fluctuating & shifting in nature. Asymmetric when B/L. Increases with repeated closure & prolonged upward gaze. Due to weakness of levator palpabrae superioris . Not pathognomonic for MG. Worsens after TV watching /Driving /Bright Light
Bulbar
Dysarthria , dysphagia, weak mastication. ‘Hanging jaw sign’, jaw opening is > stronger than closing. Low fading, MUSHY voice – on hasty, laborious , continuous talk, dysphonia (laryngeal weakness).Nasal twang and Nasal timbre (hypernasal speech) (palatal weakness). Nasal regurgitation, poor gag reflex, weak tongue . Difficult swallowing and aspiration of foods. A flurry of weak & ineffective cough.
Facial
Bifacial weakness. Loss of facial expression ‘myasthanic face”. ‘Sleepy’ or ‘sorry face’ pitiable appearance. Horizontal smile – depressed grin (myasthenic snarl). Upper lips elevates transversely in an apparent snarl, smile is limited , showing only the canines as the corners are not drawn up. Difficulty in smoking and whistling. Women complain difficulty in applying lipstick as unable to purse & roll their lips.
Muscles Of Neck
Extensor > flexors. ‘HEAD PTOSIS’ – FLOPPY HEAD SYNDROME, head drops forward in older patients with selective weakness of extensors. Attentive appearance - hand supporting the dropped jaw and falling head with thumb under chin, middle finger curled under bottom lip & the index finger up the check.
Diaphragmatic & intercostals muscles: Isolated respiratory failure, Exertional stridor
Limbs & trunk:
Proximal > distal ( difficulty in rising from chairs , lifting the arms over hand , climbing stairs, combing hairs , walking , running ). Arms> legs, Symmetric involvement.
Deep tendon jerks: Preserved , BRISK in week muscles .
Muscle Wasting : Uncommon except when chronic & untreated
Sensory: Normal.
STAGES OF WEAKNESS: Maximum Weakness In 1st Year In 2/3rd Patients
Active Stage: Fluctuating symptoms over short period – progress to severity
Inactive stage: Fluctuation in strength still occurs (attributable to fatigue /illness), Burnt out stage: Most severily affected muscles become atrophied.

DIAGNOSIS
Firm diagnosis is must as MG requiring thymectomy /long term immuno therapy. To avoid inappropriate treatment, unwanted side effects in patients who do not have the disease. Non pharmacological clinical tests , Pharmacological , serological & electrodiagnostic tests are to be done.
Strategy:
Diagnosis based upon (1) Characteristic history & physical examination (2) Two +ve diagnostic tests (serological & electrodiagnostic)
Diagnostic test must include: Testing for “Serum’ Anti AChR –antibody and RNS study

Physical Examination
Detection of Ptosis : (Ocular examination)
On prolonged upward gaze or repeated closure of eye lid, Test showing ‘seesaw’ phenomenon & Herring’s law of equal innervation. Test for eye lid twich response ‘Cogans Lid Twitch’. Evidence for spontaneous eye lid retraction ‘pesudointernuclear ophthalmoplegia’ in patients of MG. Myasthenic sustained gaze fatigue. Test for ‘orbicularis oculi’ strength. Test for ‘orbicularis oculi’ fatigue ‘peak sign’. Sleep test : no ptosis after few minutes rest. Safe, moderately sensitive & specific way to confirm improvement lasts for 2-5 mins. (Odel et al, 1991).
Ice Test:
Local Cooling: (from 35 – 360 C to 280C)
Decreases decremental response, NM gitter , weakness &#61614; ptosis improves, Positive response in 80% of MG patients.
PHARMACOLOGICAL METHODS:
Tensilon Test
Drug: Edrophonium (10mg)
Action: Inhibits AchE, Prolongs presence of ‘ACh’ in NMJ, increases muscle strength
Time Course: Rapid onset within 30-45 seconds, short acting. Result last for 2 minutes
Procedure: Initially 2mg IV, Observe for 2 minutes – No response – Add 8 mg, Look for weakness of Extra Ocular Muscles (EOM), Impairment of speech, Length of time patient can keep arms forwards in abduction, Fight with 0.6 mg atropine when troublesome
Utility: Useful only in patients with objective , preferable , measurable findings, Sensitivity for MG –relatively low - 60%, Should not be used in dose adjustment of pyridostigmine, False +ve - In LES, localized intracranial mass lesion, ALS (Amyotropic lateral Sclerosis).
Prostigmin Test :
Utility: In diagnosis of MG in patients with diplopia without ptosis, in non-co-operative children where IV tensilon is unsuitable
Procedure: Inject 0.6 mg atropine + 1.5 mg prostigmine &#61614; IM into deltoid
Result :Change in ocular motility & ptosis within 15 seconds, most obvious in 30 seconds,
Dose in Children: 0.04 mg/kg not > 1.5 mg ( total dose ). Negative result does not ruleout the disease
SEROLOGICAL:
a. Anti AChR Antibody Test:
Gold standard diagnostic, highly specific. It is +ve in 80-85% of Gen. MG , 50-60% in ocular MG, 50% in childhood MG, 100% in MG with thymoma.
Procedure : Detection through RIA by ACh – receptor labeled by I 125 or &#61537; Bungarotoxin
Interpretation : High titre does not correlate with severity, Mild disease can have high titre, Decreases Titre (>50%) indicate favorable response to treatment, Negative test does not exclude the disease, False +ve in - ALS, LES (13%), Primary Lung cancer , Older patients (> 70 years) , Neuromyotonia
b. Anti MuSK Antibodies:
+ve in few group in SNMG patients, ‘Abs’ not seen in sera of normal person nor concurrently with Anti-AChR antibodies.
ELECTROPHYSIOLOGICAL DIAGNOSIS
A. RNS (Repeated N. Stimulation):
Most frequently used electro diagnostic (ED) test.
Caution : Withdrawal of AChE medication 6-24 hour before
Muscle choice : Weak muscles or proximal muscle group.
Procedure: Electrical N. stimulation 6-10 times @ 2-3 Hz and recording of Compound Muscle Action Potential (CMAP) with surface electrodes over muscle.
Result: Progressive rapid reduction /Decremental response of ‘CMAP’ > 10-15% from 4th response onwards.
Interpretation: CMAP is normally unchanged or 4th response is slightly smaller than 1st (7%), Significant when decreases > 10%.








Single Fibre Electromyography (SF- EMG):
Most sensitive (95%) in both General and Ocular MG
Principle : Muscle fibres innervated by single axon., Normally activated with consistent latencies, ‘Jitter ‘ the mean inter potential difference between 2 fibres, Increase variability seen in NMJ disorder, Normally < 55&#61549;s. But >100&#61549;s in MG
Interpretation: Abnormal Jitter may not be specific for MG, Also seen in the ALS, LEM , Polymyositis, More specific with large degree Jitter

OTHER DIAGNOSTIC TESTS:
&#61656; CT, MRI, X-ray : Screening of Thymic tumor. Greater yield in > 40 years age.
&#61656; CBC, ESR, TFT, PFT, FBS , Montoux, RA Factor , ANA etc., to screen associated disorders.
OTHER ASSOCIATED AUTOIMMUNE DISORDER:
&#61656; Thyroid disorder (13% of MG)
&#61656; Rheumatoid- Arthritis , SLE, Sarcoidosis , polymyositis, Ulcerative. Collitis, Pemphigus
DIFFERENTIAL DIAGNOSIS
A. Lambert Eaton Syndrome
A presynaptic disorder (Autoantibodies against Ca+2 channels at Motor N. Terminals). Never begins with ocular weakness. Weakness in legs > arms. Depressed & absent reflexes. Shows autonomic changes - dryness, dry mouth , impotence. Increment RNS response
B. Neurasthenia
‘Jerky release’ or ‘Give away weakness’ in muscle testing. C/o tiredness or apathy or decreased muscle power on repeated use.
C. Botulisim
Generalised weakness, Internal & External ophthalmoplegia, Respiratory paralysis. Dilated pupil and incremental response on RNS
D. Hyperthyroidisim : Abnormal ‘TFT’
E. Inherited “MG’: Persistence weakness begins in infancy /early childhood, Muscle biopsy changes don’t explain degree of weakness
F. Intracranial Mass Lesion : Example-Sphenoid ridge meningioma’
Procedures ‘DIPLOPIA” mimicking ‘MG’ illness, Detected by CT/MRI
TREATMENT
&#61656; Modern treatment is highly effective with ‘0’ practical mortality rate (30% before 1958).
Available Tx modalities:
1. AChE inhibitors 2. Plasmapheresis
3. Corticosteroids 4. IV immunoglobulins
5. Immunosupressants 6. Thymectomy
Principle: To minimize the ACh activity at the remaining AChR in the NMJ, To limit/abolish immunological attack on motor end plate.
ACHE INHIBITORS:
Pyridostigmine (MESTINON):Usual 1st line treatment to tie up the progressive MG
Regular Mestinon pills:
• 60mg tabs /(Syp 60mg/5ml)
• Dose: Started with 30 mg , increased gradually, Tailored as per individual requirement, Higher dose –ineffective, more S/E. increases weakness
Time span pills: Sustained release ’90-180mg , used at bedtime , acts over 12 hrs
Advantage: Few Side effects
Disadvantage:
Cholinergic crisis, (symptoms increases with ACh), Effective only in some patients, Muscarinic crisis (Abdominal pain, Diarrhoea) - managed with propanthelene /Diphenoxylate
CORTICOSTEROIDS:
Used for moderate to severe type of MG. Needs prior discussion with patient about S/E & long duration of treatment. Started with low dose 10-20 mg/day to avoid early worsening (48%) on high dose regimen. Increased 5mg every 3rd day upto 60mg. After 3 months higher dose treatment, dose modified to alternate day regimen then gradually tapered. Need months to years to determine the minimal effective dose. Patient may require additional dose on OFF days. Disadvantage: S/E - weight gain/HT/OP/Aseptic necrosis of hip /cataract/ immuno suppression. Needs regular monitoring of BP, FBS, Sr. K+, Bone density (during long term treatment)

IMMUNOSUPRESANTS:
(Azathioprine/cyclophosphamide /cyclosporin /mycofenolate mofetil)
Azathioprine : (Imuran)
1st choice drug because of relative ‘safety’
Dose : 2.5 –3 mg/kg/qd – initial dose
1.5 – 2.5 mg/kg/qd – Maintenance Dose
Indication : Long term immuno suppression , sparing of steroids , decreased S/E.
Monitor: CBC , Platelet, LFT, MCV of Red cells
Advantage: Less S/E
Disadvantage: S/E – Increase risk of malignancy, Decrease RBC, WBC, Platelets. Liver dysfunction, Flulike syndrome (20-30%) (Azathioprine can not be restarted) , Long onset at action and costly
Cyclosporin ‘A’
Dose : Initial 2.5 mg/kg/day, Maintenance – Lowest effective dose
Indication: Long term immunosuppression, When prednisolone cannot be used /ineffective, When rapid response is desired.
Monitoring: RFT, BP, Blood Level (12 hr after previous dose)
Advantage: Short onset of action (1-3 months)
Disadvantage: Serious S/E (Dose related) 35% of patients. Nephrotoxicity , drug interaction with NSAID , Amphotericine -B . Increase risk of malignancy, high cost. Teratogenic , needs serum level monitoring
Mycofenolate mofetil
Dose : 1 gm BD
Indication : Long term , immunosuppression
Advantage: Low risk of malignancy , no major organ toxicity
Disadvantage: High cost , delayed onset of action (6-12 m), limited experience of utilization

PLASMAPHERESIS (PP)
Dose : 5 exchanges (3-4L/Exchange) over 2 weeks period
Indication : Acutely ill patients of MG, Prethymectomy in patients with respiratory /bulbar involvement, Not for long term treatment
Advantage: Very short onset of action (3-10 days), More effective than ‘Human Ig’ in crisis.
Disadvantage: High cost, requires specialized hand and centre, short term benefit, more complication in elderly, side effect > IV Ig
IV. IMMUNOGLOBULIN
Dose : 2 grams /kg (> 2-5 days) (400 mg/kg/day Average)
Indication: Acutely ill MG patients , not for long term treatment
Advantage:
Easy administration , improvement in 70% of patients, widely available , Rare serious S/E, Less S/E than PP (headache, fluid overload, renal shut down , aseptic meningitis)
Disadvantage:
High cost, benefit not well demonstrated, short term benefit, less effective in crisis.
THYMECTOMY
(Removal of source of continued Auto Antigen, B-cells , immunomodulations)
Indications: a. Thymoma b. Gen. MG patients (~ 8 to 55 years)
Approach : Transsternal (standard method, always with thymoma)
Transcervical (performed under direct visualization)
Drawback: Requires Experienced Skill hands
Caution “ ‘Muscle relaxants ‘ should be avoided prior to surgery.
Special Situations
1. Myasthenia & pregnancy :
Myasthenic women : 1/3rd improve & 1/3rd remain unchanged , 1/3rd worsens. Worsening most common in 1st pregnancy , 1st trimester, most common in 3rd trimester & post partum exacerbation in subsequent pregnancies. IV AchE inhibitors contraindicated – as produce uterine contraction . No contraindication to steroids reported. Uterus escapes being made up of smooth muscles – so no obstetric complication in delivery. Myasthenic weakness noticed in 2nd stage of labour when voluntary striated muscles are used. Regional anaesthesia used for Caesarean. Decreased fetal movement indicates ‘Intrauterine myasthenia’. Infant may have ‘Arthrogryposis multiplex congenita’
2. Myasthenic crisis
When associated with respiratory paralysis. Requires urgent respiratory support, ICU management (with antibiotics , fluids, AchE Therapy, plasmapheresis, IV Ig). Precipitated by infection , surgery, rapid tapering of immunosupresants. Indication of Respiratory assistance - unable to maintain: Inspiratory. Force > 20 cm H2O, Tidal Volume = 4-5 ml/kg , Maximum breathing capacity 3 times tidal vol.

3. Penicillamine induced MG
Seen in patient of RA, Wilson’s Disease, Cystinuria under D. Penicillamine. Restricted to ocular muscles. Symptoms remit after 1year stoppage of drug. Symptoms relieved by AchE inhibitors
PROGNOSIS
Untreated MG = 10 years mortality in 30 – 40%. Most patients lead normal life with life long immunosupressants. MG+thymoma in older age patients – poor prognosis (5 year survival in 30% cases)
CONCLUSION
Improved understanding of ‘AChR’ structure. Ab. Response in SNMG – better explained. Increased diagnostic sensitivity obtained using ‘Anti AChR ‘E’ subunit specific abs instead of ‘AchR’. Photopheresis with blood lymphocytes exposed to UV radiation – have a prolonged remission. Mycophenolate occupies important place in treatment field with greater safety. CT guided percutaneous ethanol injection to thymoma – shown effective, minimally invasive & safe in treatment of MG. Modern treatment is highly successful & mortality of treated disease is ‘O’ but the goal of elimination of autoimmune response to ‘AchR’ specifically without otherwise interfering with immune system is yet to be achieved.
CLINICAL FOCUS
MG is the commonest autoimmune disorder of NMJ characterized by weakness and fatiguability of voluntary muscles. Higher incidence in women and above 40 years, It is classified according to age, presence of AChR antibodies, severity and etiology. The fundamental defect is decreased AChR at PSM , reduced SF, leading to decline of muscle power of RNS, flattened postsynaptic fold and production of small EPP, shortening of synaptic fold and widening of synaptic cleft. AChR antibodies detected in 80% -90% cases. Ocular muscles are commonly involved producing ptosis and diplopia. Bulbar involvement produce dysarthria, dysphagia difficulty in mastication and deglutition and MYSHY VOICE . Facial involvement produces typical Myasthenic face, with associated day to day difficulties. DTJ are preserved. Muscle atrophy is rare. Sensory systems are not effected. Diagnosis depends on clinical examination, Pharmacological, Serological and Electrophysiological tests. There may be some associated autoimmune disorders. Modern treatment modalities are effective with ‘0’ mortality.
REFERENCE :
1. Clinical Neuro-ophthalmology , Vol – 1.
2. Clinical Care Neurology, 2nd Edition , ELCO F.M. WIJDICKS.
3. Neurology in Clinical Practice , Vol 2, 2nd Edition, Bradley
4. API Text Book of Medicine , 7th Edition
5. Web Sites: Pubmed & Googly.com
. Myasthenia gravis Article by Aashit K. Sah, MD, Aug, 2 , 2004
.Update on myasthemia Gravis by Tanvi & Co , Postgraduate Medical Journal (950)690.
. Myasthenia Gravis & Summary by James F Howard, Jr. MD.


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Jul21
IRRITABLE BOWEL SYNDROME
INTRODUCTION

The commonest GI disorder at present is Irritable Bowel Syndrome(IBS). Though first diagnosed 2 centuries ago IBS still remains poorly understood by physicians and patients around the World. With the availability of better technique to study GI motility and visceral functions along with the development of newer concept on importance of brain in regulating gut function significant progress has been made for better understanding of IBS. Here the current knowledge of IBS reviewed.

DEFINITION
Functional bowel disorder like IBS is defined as chronic , recurrent GI tract disorder without any organic or structural lesion . Various studies have tried to define IBS. Manning criteria (1978), Rome I criteria (1989), Rome II criteria (1998) were few studies to define IBS. The more acceptable definition is Rome II criteria.
Rome II Criteria for diagnosis of IBS
At least 12 weeks, which need not be consecutive in the preceding 12 months of abdominal discomfort or pain that has 2 of the following 3 features
1. Relieved by defecation
2. Onset associated with change in stool frequency
3. Onset associated with changes in stool pain

PREVALENCE AND EPIDEMIOLOGY
Prevalent Worldwide affecting 4% to 35% adults, common in woman than man. Woman make up 80% of population with severe IBS. In most patients the symptoms starts in late teenage or early 20s, (3rd and 4th decade) and decreases in 6th and 7th decades. After 60 years diagnosis of IBS is to be differentiated from other diseases like colon cancer and diverticulitis.
PATHOPHYSIOLOGY
A connection between brain and gut was proposed by Almy and Mullin by observing colonic motility changes related to stressful information. IBS is a complex disorder in which various physiologic process are involved , like abnormalities of intestinal motility, alteration of visceral sensory function , changes in CNS processing of sensory information’s, psychological stress and luminal factors. Interplay between gut and CNS has been called as Brain –Gut axis.


1. Altered gut motility motor activity
In IBS patients antroduodenal manometry study shows discrete clustered contraction of small intestine. These are bursts of rhythmic contractions and associated with abdominal pain. In other very prolonged contractions are seen within colon or small intestine or very high amplitude propagating contractions within the colon, more in postprandial period with episodic abdominal pain. Alteration of migratory motor complex may either delay (constipation ) or accelerate (diarrhoea) intestinal transit . It reflects the exaggeration of normal GI motility pattern. The motility pattern differs in different patients. Colonic myoelectrical & motor activity studies shows abnormalities under stressful conditions in IBS. They may exhibit increased rectosigmoid motor activity upto 3 hours after eating. Provocative stimuli like inflation of rectal balloon may lead to distention evoked contractile activity. Recording from transverse descending , sigmoid colon show high amplitude of motility index and peak amplitude in diarrhea prone IBS.
2. Enhanced Visceral Sensitivity:
Abdominal pain is a critical part of the criteria, the cause of which is not yet established. It has been demonstrated that there occurs an increased sensitivity to pain within GI tract (by balloon inflation study at various level in GI tract).Exhibit exaggerated sensory response to visceral stimuli, postprandial pain is related to entry of food to caecum in 74%. The visceral hyperalgesia appears to be selective for mechano-receptor activated stimuli as perception of intestinal mucosal electrical stimulation is normal in IBS.
Lipids lower the threshold for the first sensation of gas, discomfort and pain in IBS. The area of referred pain after lipid ingestion is increased. So postprandial symptoms are explained by a nutrient dependant exaggerated sensory components of gastrocolonic response. IBS patients don’t exhibit increased hypersensitivity anywhere in body. So disturbance is selective to visceral innervations rather than somatic.
The increased response may be due to (a) Increased endorgan sensitivity with recruitment of silent nociceptors. (b) Spinal hyperexcitability with activation nitric oxide and other neurotransmitters.(c) Endogeneous (cortical and brain stem) modulation of caudad nociceptive transmission.Development of long term hyperalgesia due to neuroplasticity resulting in permanent or semipermanent changes in neural response to chronic or recurrent visceral stimulation.
3. Influence of CNS
• In patients of IBS sensory processing is altered outside GI tract. It has proved by various studies.
a. Positron emission tomography scanning of CNS during ballon distention in IBS patients showed increased activity in prefrontal area associated with anxiety , hypervigilence and reduced activity in anterior cingulate cortex an area important for opioid binding. IBS patients exhibit no increased blood flow in the anterior cingulate gyrus but show activation of the prefrontal cortex in response to rectal activation or rectal distention. Activation of frontal lobe may activate a vigilance network and alertness. The anterior cingulate cortex and prefrontal cortex have a reciprocal inhibitory effect. Thus in IBS the preferential activation of prefrontal lobe without activation of anterior cingulate cortex may represent a form of cerebral dysfunction leading to increased visceral pain perception.
b. Functional MRI also showed different CNS activity in IBS patients.
• These studies suggest that IBS patients may process sensory information from GI tract differently than non IBS. Besides other, stimuli like stress, anxiety, depression may modulate sensory processing and influence the perception of pain.
4. Other factors
(a) Infection – Infectious gastroenteritis may increase the like hood of IBS in later life. The mechanism of post infectious IBS may be due to (i) Transient or permanent damage of enteric nervous system, the intrinsic nerve supply responsible for coordinating GI peristalsis. (ii) Development of immune hypersensitivity in which repeated exposure to benign substance induces inflammation and altered motility. (iii) Infectious agent initiates a cycle of chronic mucosal inflammation leading to altered gut motility.
Common in women and younger patients. Microbes involved are Campylobacter, Salmonella, Shigella Increased rectal endocrine cells, T – Lymphocytes and gut permeability are acute changes following Campylobacter which contributes to post infective IBS.
(b)Role of physical and sexual abuse
Several studies have shown higher incidence in physical and sexual abuse cases specially in woman. Forms of sexual abuse includes verbal aggression, exhibitionism, sexual harassment, sexual touching, rape. The pathophysiology is unknown and pain threshold is not lowered.
(c) Psychiatric factor
Recorded in 80% cases of IBS. No single psychiatrics diagnosis associated. Most patient demonstrate exaggerated symptoms . Influences pain threshold, stress alters sensory threshold.
(d) Hormonal
Serotonin (5HT) containing enterochromaffin cells in the colon and postprandial plasma 5HT are increased in Diarrhoea predominant IBS. As 5 HT plays important role in GI motility they are responsible for pathogenesis and treatment by 5 HT antagonist.

DIAGNOSIS
With a through interview and physical examination IBS can be diagnosed at the first visit. Physicians should not down play the symptoms on the ground that they exist in patients mind. Because physiologically and therapeutically definite GI motility and visceral sensation abnormalities exist in IBS patients. The accuracy of diagnosis may be 97% by proper evaluation of symptoms , normal physical examination and normal simple laboratory test. Diagnosis on basis if Rome II criteria in practically less useful for its restrictive nature. Currently American College of Gastroenterology recommends the broad definition for clinicians- Abdominal pain or discomfort associated with altered bowel habit and absence of warning signs or “red flags” suggestive of organic disease.
SYMPTOMS
The pattern of symptoms (abdominal pain , altered bowel habit) varies from person to person but remain consistent in same individual varying in intensity and frequency. Typically symptoms are intermittent with symptom-free period lasting for days , weeks or months. Rarely patients have daily symptoms.
A. Abdominal pain
Hallmark of IBS. Duration – for at least 12 weeks during preceding 12 months (need not be consecutive) or more than 25% of time during preceding 3 months. Related to defecations anyway . Intensity quality – Varies among patients but remains stable for individual patients. Described as crampy or sharp or burning May be episodic with a background of consistent for individual. Location:Hypogastium (25%), right side (20%), left side (20%) and epigastrium (10%) . Pain may be mild to be ignored or interfere daily activities. Malnutrition due to inadequate coloric intake is rare. Sleep deprivation is rare as it occurs in day and waking hours. In severe IBS may be associated nocturnal pain with poor prognosis. Pain often exacerbated by food or stress and relieved by passage of stool or flatus. Females have worsening of symptoms during premenstrual and menstrual cycle.
B. Bowel habit
Normal bowel movement ranges from 3 per week to 3 per day. The altered bowel habit varies in patients but remains consistent for individual. Three patterns are observed – Diarrhoea, constipation or alternating diarrhoea and constipation (most common). Patients having diarrhoea usually have normal consistency is morning but subsequent bowel movement becomes loose associated with urgency, abdominal cramp, flatulence and sense of incomplete evacuation. Stools become more liquid associated with mucous and feeling of drained out. Small volumes of loose stool (< 200 ml). Nocturnal diarrhoea does not occur in IBS. Diarrhoea is aggravated by food or stress. May be associated with large amount of mucous. Bleeding is not usually unless associated haemorrhoid and malabsorption and weight loss do not occur. Patients with constipation complains of rocky hard stool (scybala) associated with straining and incomplete evacuation and associated mucous . Initially may be episodic eventually becomes continuous and gradually intractable to laxative treatment.
C. Fecal incontinence
Staining of undergarments occurs in 20% of IBS. More marked in cases of IBS with diarrhoea or diarrhoea alternating with constipation. May be due to repetitive relaxation of sphincter muscles with repetitive colonic spasm.
D. Bloating and abdominal distention (Gas & Flatulence)
Very common and due to increased abdominal gas or increased sensitivity of gut to normal gas. Some patients of IBS has aerophagia, and increased belching and flatulence. Though increase in gas is complained intestinal gas amount is normal. IBS has impaired transit and tolerance of intestinal gas and tendency to reflux gas from distal to proximal.
E. Other constitutional symptoms
1. Weight loss – No weight loss
(if weight loss question about warning or “Red flag “ sign)
2. Anaemia /GI bleeding /Stool occult blood – Unusual
3. Fatigue, myalgia, arthralgia, fever, chill, night sweat – rare
F. Upper GI symptoms
25 to 50% of IBS complain dyspepsia, heart burn, nausea and vomiting. Overlap between IBS and dyspepsiaoccurs . In IBS case 55 % complain dyspepsia and in dysopeptic patients 31.7% have IBS. This functional disorder may fluctuate and indicate a single , extensive G.I disorder. IBS are more prevalent in patients having noncardiac chest pain.
PHYSICAL EXAMINATION
Thorough physical examination is needed to exclude any associated disease or make a second diagnosis. Generally the physical examinations are normal. P/A examination shows some tenderness due to visceral hypersensitivity , rectal spasm and muscular contraction. Any significant mass, tenderness or bleeding warrants other causes. Suggestive features of IBS include recurrence of abdominal pain with altered bowel habit over a period of time without progressive deterioration, onset of symptoms during stress or emotional upset, without any systemic symptoms like fever, weight loss and small volume of stool without evidence of blood. On the other hand the disorder appearing first time in old age , with a progressive course from onset , persistent diarrhoea after 48 hr fast, nocturnal diarrhoea, steatorrhoea excludes IBS.
DIFFERENTIAL DIAGNOSIS
As per the triad of symptoms in IBS the list of D/D is long.
a) Quality, location , timing of pain may help for specific disease. Pain in epigastric & periumbilical – biliary tract disease, peptic ulcer, intestinal ischaemia, Ca stomach and pancrease.
Postprandial pain with nausea, bloating – gastroparesis, partial intestinal obstruction, giardia and other parasite infestation.
b) Diarrhoea – Lactase deficiency, lexative abuse, malabsorption, hyperthyroidism , inflammatory bowel disease, infectious diarrhoea.
c) Constipation – Side effects of drugs like anticholinergics , antihypertensives and antidepressants, hypothyroidism and other endocrinopathies . Acute intermittent porphyria and lead poisoning.
INVESTIGATION
The goal is to: establish early diagnosis, find co-existing and alternative diagnosis, avoid unnecessary procedures. Certain guidelines have been delineated for diagnosis evaluation. They include duration of symptoms , the change in symptoms over time , age and sex, referral status of the patient, prior diagnosis studies, family history of colorectal malignancy, psychosocial dysfunction. Laboratory features that argues against IBS are – evidence of anaemia, raised ESR, leucocytes or RBC in stool, stool volume > 200 to 300 ml/d. Although extensive tests were followed in the past but it is now recognized that no test is necessary in younger patients who meet the criteria of IBS and have normal clinical findings without ‘red flag’ signs. But in the era of medical malpractice objective tests are necessary. A complete blood count, measuring ESR and C-reactive protein level is necessary if it is recent . If constipation is predominant estimate thyroid function test . If diarrhoea predominant –stool is tested for leucocytes and subjected to culture and examine for ova or parasites. Stool should be tested for Clostridium difficile. If persistent diarrhoea-serological test to exclude Celiac disease because incidence of celiac disease is 10 times more in IBS than normal. Flexible sigmoidoscopy – in young (< 40 years) having altered bowel habit, rectal discomfort. Colonoscopy – In age above 50 years , having family history of inflammatory bowel disease, colorectal cancer or anaemia. Upper GI endoscopy, oesophagogastroduedenoscopyy, ultrasonogram may be done to rule out other causes.
TREATMENT
General Principles : primarily focused on symptomatic relief through various modalities like patient education and reassurance, diet , supportive and behavioral therapy and pharmacotherapy. Successful management requires physicians understanding and patients knowledge and confidence. Chronic nature of the disease requires prolonged cooperative endeavor on the part of physician and patient. Treatment starts at first visit of the patient when the patient develops care and confidence on physician in way of meticulous interview and thorough physical examination. Contributing factors like diet , emotional state professional and interpersonal relationship and fear and concern are to be considered. Patient is to be explained the pathophysiology, influencing factors, chronicity of the disease.
DIET
Though many patients attribute to food allergy, true food allergy is uncommon in IBS. The act of eating may precipitate bloating, gas or abdominal discomfort. Some patients may relate the symptoms to some specific diets which are to be avoided if the symptoms recur on at least 2 occasions of stopping and reintoduction of the diet. The commonest genetic disorder Lactase insufficiency may be associated with IBS. This can be established by inducing symptoms following milk drink or relief of symptoms by giving lactose free diet.
PHARMACOTHERAPY
Due to complex pathophysiology no single agent has been able to cure IBS. Treatment is targeted at relieving individual symptoms. However FDA has approved 2 drugs which relieves multiple symptoms. (a) Tegaserod – Relieves global symptoms of IBS with constipation (Pain , bloating, discomfort & constipation). (b) Alosetron – Relieves global symptoms of IBS with diarrhoea.
I. CONSTIPATION
1. For patients of mild symptoms: life style modification, change in diet, use of fibre supplement, daily fluid intake minimum 64 OZ, food with natural fibres, use bathroom at a set time are to be tried.
2. If this is effective fiber supplementation like : I) Methylcellulose, psyllium ii) Polycarbophil, coarse bran iii) Ispaghula husk are used .These products are hydrophilic agents binding water and prevent dehydration . Only three studies have been significant 1 for polycarbophil and 2 for ispaghula husk. These agents produce bloating and distention in 30% cases. Magnesium hydroxide (Tab , Liq) may be used for constipation , though does not relive abdominal pain and bloating. Long term magnesium is harmful in renal insufficiency. Recently fiber supplementation with psyllium has been shown to reduce perception of rectal distention, indicating that fiber may have a positive affect on visceral afferent function. Beneficial effect of fibers on colonic physiology suggest an effective treatment though results of various trials are variable. Most investigations report increase in stool weight, decrease in colonic transit time , improvement of constipation. A crossover comparison of different fiber preparations found that psyllium produced greater improvement in stool pattern and abdominal pain than bran. Psyllium produces less bloating and distention. Despite equivocal data regarding efficacy stool bulking agents are worth trying in IBS.
3. Medication includes (a) Lactulose (b) Polyethylene glycol (c) Prostagladin agents – misoprostol (d) Colchicine (e) Tegaserod (5HT4 agonist ).
Tegaserod - Stimulates prokinetic activity by stimulating peristalsis. In constipation tegaserod accelerates intestinal and ascending colon transit. It selectively binds to serotonin type 4 (5 HT4) receptors in the gut and directly initiates peristalsis. It relieves constipation, accelerates orocaecal transit, bloating and abdominal pain in 2/3rd patients. It is recommended as Grade A drug for relieving global symptoms. Side effects is diarrhoea and ischaemic colitis.
Table – 1
Selected medications used for constipation in Irritable Bowel Syndrome
Drug Dosing Common side effects Comments
Fiber products Coarse bran
Ispaghula husk
Methylcellulose
Polycarbophil
Psyllium 1-2tsp/d; advance as tolerated
20g/d
0.5-1 T (1-2g) qd-tid
625 mg qd-tid
3.4 g qd-tid Bloating, abdominal distention Anecdotal; few controlled trials
Osmotic agents Lactulose
Polyethylene glycol 15-30ml (10-20)qd-tid
17g/d Bloating, cramps, flatulence
5 HT4 agonist Tegaserod 6 mg bid ac for 4-6 wk; if response positive, can consider additional 4-6 wk Headache, diarrhoea Grade A recommendation by ACG; warning issued in April 2004 about potential for serious consequence of diarrhoea and a precaution for rare, ischemic colitis
Others Colchicine


Magnesium hydroxide 0.6mg/d



622-1, 244 mg qd-qid Nausea, vomiting, diarrhoea, abdominal pain

Diarrhoea, cramps
May worsen symptoms in some patients , long term safety unknown
Mild constipation only; avoid long term use in patients with renal insufficiency

II. DIARRHOEA
Peripherally acting opiate based agents are the initial therapy of choice in diarrhoea predominant IBS. Physiologically they produce increase in segmenting colonic contraction, delay in faecal transit, increase in anal pressure and decrease in rectal perception. They are most useful when taken before anticipated stressful events. The use of antidiarrhoeal should be considered as temporary management, with a final aim of gradual withdrawal of drug with substitution of high fiber diet . Medication are Diphenoxylate HCL – Atropine, Loperamide – By increasing gut transit time it allows more fluid absorption. By increasing external anal sphincter tone decreases incontinence and soiling, Tricyclic antidepressants (TCA) – in low doses decrease frequency , Calcium channel blockers – decrease motility in some cases, Deodorized tincture of opium (DTO), Alosetron – A 5 HT3 receptor antagonist.
Alosetrin : Evaluated in diarrhoea predominant IBS. Serotonin acting on 5HT3 receptor enhances the sensitivity of afferent neurons projecting from gut. Alosetron , the drug reduces painful visceral sensation, induces rectal relaxation , increases rectal compliance, delay colonic transit time, improves stool frequency, consistency and urgency. Women respond better than man. However due to sideeffect like ischaemic colitis the drug has been withdrawn. Newer 5HT3 receptor antagonist Cilansetron have same effect as alosetron, but needs further follow up trial.

Table – 2
Selected medications used for Diarrhoea in Irritable Bowel Syndrome
Drug Dosing Common side effects Comments
Antidiarrheals Diphenoxylate
HCL –atropine

Leperamide 5 mg tid-qid


2-4 mg qid, up to 16mg/d • Bloating constipation, loss of appetite , abdominal pain, nausea, vomiting
• Abdominal pain and distention, constipation , dry mouth, nausea, vomiting Discontinue as soon as diarrhoea is controlled
Resin-binding agent Cholestyramine 4 g qd-bid Constipation , flatulence , can decrease absorption of other drugs
Opioid DTO 0.6ml qid , upto 2.4 ml/d Sedation , constipation Do not confuse with paregoric – DTO contains 25 mins more morphine than paregoric
5HT3 antagonist Alosetron 1 mg qd for 4 wk; if tolerated can be increased t 1 mg bid Constipation Grade A recommendation by ACG; discontinue immediately if constipation or signs of ischemic colitis develop; limited use program , efficacy not established in men.
Others TCAs: amoxapine
amitriptyline
alomipramine
desipramine
doxepin, imipramine
nortriptyline, protriptyline
trimipramine Various Dry mouth, dry eyes, sedation, weight gain, cardiac arrythemias, hypotension , constipation Small studies have shown reduction of abdominal pain

III. ABDOMINAL PAIN
a) Smooth muscle antispasmodic agents though used with dubious beneficial effect they are useful when pain is associated with meal and who have tenesmus. The anticholinergic drugs are to be taken 30 to 60 minutes prior to food. A metaanalysis of 26 double blind trials of antispasmodics in IBS reported better global improvement (62%), reduction in abdominal pain (64%). They are most effective when given in anticipation of pain .
b) Several TCA (amitriptyline, nortryptiline, desipramine) Though effective but side effects limit their use. Antidepressant drugs – Besides mood elevating effects, they have some physiological effect. In diarrhoea predominant IBS, imipramine slows jejunal migrating motor complex propagation and delay orocecal and whole gut transit indicating motor inhibitory effect. Tricyclic agents alter visceral afferent neural function. In another trial desipramine has shown improvement of abdominal pain (86%), improvement in stool frequency. The effect is better in diarrhoea predominant IBS than constipation. The beneficial effects of TCA on IBS is independent of anti-depression action.
c) Selective serotonin reuptake inhibitors (SSRI) may relieve pain . The efficacy of other classes of antidepressants in IBS is less evaluated. The SSRI –paroxetine accelerates orocecal transit may be useful in constipation. Citalopram blunts perception of rectal distention and reduces pain.
d) Analgesics are to be avoided . If indicated should be prescribed at low dose. Nacrotics should not be prescribed.
e) Tegaserod – relieves global symptoms including abdominal pain .

Table – 3
Selected medications used for pain in Irritable Bowel Syndrome
Drug Dosing Common side effects Comments
Anticholinergic agents Glycopyrrolate 1 mg tid Fatigue, dry mouth , constipation, urinary retention
Antismasmodic agents Dicyclomine HCI Start with 10mg qid; can increase to 40 mg qid Dry mouth , dry eyes mild sedation, urinary retention High incidence of side effects at this dose; tachycardia and orthostatic hypotension occur uncommonly
Others Acetaminophen 325mg q4-6h prn; 4,000 mg/d maximum Liver injury used at high doses, especially if taken in combination with alcohol Included in this table because commonly used OTC, but generally not effective; no controlled trials
Carbamazepine 100mg bid day 1; can increase by up to 100 mg bid prn, 1,200 mg/d maximum Anorexia, drowsiness, nausea, elevated gepatic enzymes Black box warning for aplastic anemia and agranulocytosis
Gabapentin 300 mg/d; can titrate t0 1800 mg/d in divided doses Dizziness, somnolence peripheral edema
SSRIs: Citalopram, escitalopram, fluoxetine, fluvoxamine, paroxetine, sertraline Various Sedation, fatigue, sexual dysfunction , weight gain Efficacy in IBS not established; published are conflicting
Tramadol After titration , 50 mg q4-6h prn; 400 mg/d maximum Dizziness, nausea, constipation, headache, somnolence Possible addicition potential
TCAs Various Dry mouth, dry eyes,sedation, weight gain, cardiac arrythmias , hypotension Small trials , abdominal pain may be relieved

IV. BLOATING (ANTIFLATULENCE THERAPY)
Most difficult symptoms to treat, Most medications are not fully effective, Simethicone and activated charcoal provide relief in some case, Tegaserod is effective, If there is aerophagia advise to eat slowly, avoid chewing gum or drinking carbonated beverages, artificial sweetner , legumes and cabbages.

Table – 4
Selected medications used for bloating in Irritable Bowel Syndrome
Drug Dosing Common side effects Comments
Antispasmodic agent Clidinium 2.5 – 5 mg tid-qid ac ,hs Fatigue No controlled trials, off label use
Dicyclomine HCI Start with 20 mg qid; can increase to 40 mg qid Dry mouth, dry eyes, mild sedation , urinary retention High incidence of side effects at this dose; tachycardia and orthostatic hypotension occur uncommonly
Hyoscyamine 0.125 – 0.25 mg tid – qid or 0.375 – 0.75 mg SR bid Dry mouth, dry eyes , fatigue, urinary retention
Phenobarbital hyoscyamine-atropine-scoplamine 1-2 tablets bid-qid Fatigue,sedation, blurry vision
Antiflatulence Simethicone 2.4 125 mg tablets ac Safe; rare side effects; efficacy not established
Charcoal 1-2 125 mg tablets ac and hs Altered absorption of other medications , discoloration of stool Efficacy not established
5HT4 agonist
Tegaserod 6 mg bid ac for 4-6 wk; if response, can consider additional 4-6 wk Headache, diarrhea Grade A recommendation by ACG, safety and efficacy not established in men.

V. PSYCHOLOGICAL TREATMENT
Recognize if anxiety , depression , panic disorder or somatic disorder. Psychological evaluation and management at physician level without referring to psychiatrist for better patient compliance. The treatment is usually a multifocal approach including patients awareness through counseling, cognitive behavioral therapy, stress management , use of drugs to treat associated or underlying psychological disorder.
VII. ALTERNATIVE MEDICINES
Some use peppermint oil to minimize pain and bloating, Some use acupuncture and hypnotherapy , Many resort to natural and herbal therapy.
The treatment strategy of IBS depends on the severity of disorder.
Table Severity of IBS
Clinical features Mild Moderate Severe
Prevalence
Correlation without physiology
Symptoms constant
Psychosocial difficulties 70% 25% 5%
+++ ++ +
0 + +++
0 + +++
Health care issues + ++ +++
Practice type Primary Specialty Referral
In mild cases the treatment involves education , reassurance , dietary /lifestyle modification. In moderate cases the treatment includes gut acting pharmacological agents like antispasmodic, antidiarrhoeal, fiber supplements and gut serotonin modulators. In severe and refractory cases are best managed with antidepressants and other psychological treatment.
CONCLUSION
In most cases IBS is a chronic disorder in which relatively symptom free period alternate with exacerbation of symptoms. In 75% of cases the symptoms persists for 5 years.
The diagnosis of IBS should be based on Rome II criteria along with through history , physical examination . Extensive and expansive tests are not required. The treatment should be early and symptomatic. The standard therapy does not always relieve global symptoms. The medications targeting serotonin system usually relieve symptoms of constipation (Tegaserod ) or diarrhoea (Alosetron).

CLINICAL FOCUS

• IBS is commonest GI disorder but poorly understood by physicians and patients.
• This functional disorder is best defined by Rome II criteria.
• Common in young females.
• Altered gut motility motor activity and enhanced visceral sensitivity along with CNS influence are responsible for the clinical features.
• Abdominal pain, altered bowel habit and bloating are triad of symptom.
• Physical examination reveals no finding.
• Laboratory diagnostic procedures are done to exclude other diseases.
• The treatment is primarily symptomatic with more stress on diet, psychological factor, life style modification and educating the patients.
• Various medication though used for symptomatic relief few are practically used. Only two drugs targeting serotonin system relieve symptoms a) Tegaserod (constipation predominant IBS), b) Alosetron (diarrhoea predominant IBS).
• IBS is still a challenging psychosomatic disorder for physicians and patient.

REFERENCE

1. Blueno L et al : Mediators of pharmacology of Visceral sensitivity: from basic to clinical investigation ; Gastroentrology 112: 1714, 1997.
2. Talley NJ : Evaluation of drug treatment for IBS : Br J Cli Pharmacol 56: 362, 2003.
3. Mertz H : IBS – N. EJM – 349: 2136, 2003.
4. Harrison’s Principles of Internal Medicine, 16th Edn, Vol II, Page 1789- 1793.


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Jul21
RECENT ADVANCE IN THE MANAGEMENT OF CHRONIC HEPATITIS B INFECTION
Though the existence of a potentially transmitted form of hepatitis was documented by Lurman in 1885 the term hepatitis A & hepatitis B were introduced by Mac calluman in 1947 to categorize infectious & serum hepatitis. By 1968 other investigators notably Pince, Okochi & Murakami had established that Australia Antigen (Hbs Ag) was found specifically in serum of hepatitis B patients. In 1970 Dane et al, detected the complete hepatitis B Virion, a 42 nm double shelled particle (Dane particle). After that various researchers and epidemiological study undergone for this particle till date & it was found that an estimated 350 million people world wide and around 43 million in India carry this pathogen that can lead to cirrhosis and hepatocellular carcinoma. Management of hepatitis B and its complication requires significant knowledge of pharmacotherapeutic option which are evolving rapidly . To date 3 drugs have been approved for treatment of chronic hepatitis B that are Injectable interferon &#61537; and oral agents like lamivudine and adefovir dipivoxil. Various new drugs and immunologic modulators hold promise for treatment of chronic HBV infection and are various stages of development.


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