This document provides an overview of amoebiasis (Entamoeba histolytica infection). It discusses the definition, life cycle, epidemiology, pathogenesis, clinical manifestations, diagnosis and treatment of intestinal amoebiasis as well as extra-intestinal infections such as amoebic liver abscess. Key points include that 90% of E. histolytica infections are asymptomatic but 10% can cause intestinal or extraintestinal disease ranging from dysentery to liver abscesses. Diagnosis involves microscopy of stool, biopsy or abscess aspirate samples. Treatment depends on the clinical presentation and involves metronidazole and other drugs.
2. Definition Amoebiasis is an infection with intestinal protozoa Entamoeba Histolytica. 90% of infection – asymptomatic. 10% of infection – Clinical syndrome. Ranging from Dysentery to Abscess of the liver or other organs.
3. PHYLUM SARCOMASTIGOPHORA SUBPHYLUM SARCODINA SUPER CLASS RHIZOPODA CLASS LOBOSEA SUB CLASS GYMNAMOEBIA ORDER AMOEBIDA SUBORDER TUBULINA “ ENTAMOEBA HISTOLYTICA ”
4. HISTORY 1875 LOSCH – RUSSIAN. Differentiated the amoebic dysentery from bacillary dysentery by describing amoeba in the stool. 1887 KARTULIS – EGYPT. Found amoeba in the pus from a liver abscess. 1881 COUNCILMAN AND COFFLEUR. Described true bowel lesions and used the term Amoebic Dysentery. 1903 SCHAUDINN. Differentiated pathogenic and non pathogenic types of amoeba.
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6. the intestinal lesion Gut Minute crypt lesion Extends through the muscularis mucosa and submucosa. “Flask shaped” ulcer Thrombosis of blood vessels “Toxic megacolon” Irreversible coagulation necrosis of bowel wall . PATHOLOGY
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13. PREVENTION Health Education Improved water supply Chlorination – not effective Amoebic cysts Destroyed by 200 parts / 10 6 of Iodine 5 – 10 acetic acid. Heating > 68 0 C Removed by sand filtration Boling for 10 minutes kill the cysts
16. PATHOGENESIS Journey of E. Histolytica to the Liver 1. Direct Extension from the Gut to the Liver 2. Via the Lymphatics 3. Along the portal stream Infarction – Enzymatic Dissolution
32. COMPLICATONS Right chest Peritoneum Pericardium Amoebic brain abscess - rare Hemobilia – Rupture in to major bileduct Portal hypertension
33. LABORATORY FINDINGS Normocytic Normochromic anaemia Leucocytosis -> more than 10× * 10 9 / L ESR Stool Cyst or Vegetative form of E . Histolytica LFT Bilirubin Transaminases more than 50 % Alkaline phosphatase more than 75 %
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35. Anterior view of 133/Rose Bengal dot liver scan showing a small cold area on the inferior surface of the left lobe .
36. 99m Tc sulphur colloid photo liver scan (anterior view) showing a cold area in the superior surface of the left lobe
37. X-ray chest showing obliterated costophrenic angle and an elevated right dome of the diaphragm
44. TREATMENT 750-800 mg.t.i.d × 10 days 500 mg t.i.d. ×10 Days 2g/day × 3-5 days 500 mg t.i.d × 10 Days 1-1.5 mg kg-1 day -1 ( max.90 mg/day ) i.v × 5 days 500 mg t.i.d × 10 days. Metronidazole followed by diloxanide furoate or tinidazole followed by diloxanide furoate dehyderoemetine followed by diloxanide furoate 1st Choice 2nd choice
45. Formal Indications To rule out a pyogenic abscess (, particularly with multiple lesions ) As adjunct to medical therapy ( No response after 72 hours ) If rupture is believed to be imminent Abscess in the left lobe where the risk of rupture is increased. Possible Indications To reduce the period of disability INDICATIONS FOR ASPIRATION OF AMOEBIC LIVER ABSCESS
47. Color – Anchovy sauce, Chocolate color or pinkish brown, varying color’s Odour – Odourless Consistency – thick , Viscosity – thick lubricating Oil , Quantity – Accroding to the size of the abscess Microscopy – Dead and deformed Hepatocytes RBC’S Few Polymorphs Trphozoites of E.Histolytica present in 10 to 25 % cases Microbiology – Sterile PUS IN AMOEBIC LIVER ABSCESS Hepatoma, livercyst, Hemangimoa DD
