Extraintestinal Amoebiasis PDF

Extra-intestinal amoebiasis The trophozoites reach these sites by: A. Haematogenous spread B. Direct contact A. Haematogenous spread Some trophozoites in large intestine invade blood vessels and are carried in the blood causing: 1. Amoebic liver abscess: the commonest type of extra-intestinal amoebi...

Extra-intestinal amoebiasis The trophozoites reach these sites by: A. Haematogenous spread B. Direct contact A. Haematogenous spread Some trophozoites in large intestine invade blood vessels and are carried in the blood causing: 1. Amoebic liver abscess: the commonest type of extra-intestinal amoebiasis 2. Amoebic lung abscess: also from liver abscess across the diaphragm 3. Amoebic brain abscess: rare but may be fatal NB: The term abscess here is a misnomer, because there is no pus Amoebic liver abscess - It occurs in about 5% of cases of intestinal amoebiasis - Commonly in the right lobe - Usually fast growing -Filled with liquefied hepatocytes & cell debris (necrotic cells) -There is no pus - Only trophozoites are detected (no cysts) Clinical manifestations The onset of the clinical manifestations may be acute or gradual The patient presents within 2-4 weeks of infection with: -fever - dull & aching abdominal pain in the right upper quadrant or epigastrium - tender hepatomegaly Diagnosis To be differentiated from pyogenic abscess & hepatocellular carcinoma Clinical Imaging Aspirate (anchovy sauce aspirate) Serological tests (ELISA). Microscopic examination of aspirate shows cell debris and trophozoites (no cysts). Nested PCR and monoclonal antibody methods. Amoebic liver abscess aspiration Rupture is a major complication Aspirate looks like Anchovy sauce: (a sauce made by smashing small fish). Aspirate Anchovy fish Amoebic brain abscess The onset of the clinical manifestations is abrupt & the progression is rapid that necessitates prompt diagnosis & treatment The clinical manifestations are non-specific depending on the number, location & size The presentation is as space occupying lesion/s Triad of amoebic brain abscess: 1. Fever 2. Headache 3. Focal neurological deficit MRI (magnetic resonance imaging) B. By direct contact Cutaneous amoebiasis: 1. Amoebic skin ulcer 2. Amoebic genital ulcer Cutaneous Amoebiasis Skin ulcer: The trophozoites reach the skin from the leakage when liver abscess is aspirated skin ulcer Cutaneous Amoebiasis Perianal & genital ulcers (labia, vagina & penis): The trophozoites reach these sites during unprotected anal intercourse with a patient with amoebic dysentery Genital ulcer Diagnosis of cutaneous amoebiasis - Clinical Microscopic detection of trophozoites in specimen from the edge of the ulcer Treatment of Extra-intestinal Amoebiasis The patient responds well to medical treatment The drugs used are metronidazole or tinidazole - In addition to abscess aspiration in case of large amoebic liver abscess (>5 cm)