Fulminant Amebic Colitis With an Atypical Clinical Presentation Successfully Treated by Metronidazole

Abstract

a e d c u A man was admitted to our hospital with a 1-week history of fever and abdominal pain. He had no history of verseas travel or contact with either men who have sex with men or ommercial sex workers. On admission, the patient’s level of conciousness had deteriorated, and the Glasgow Coma Score was 13/15 eye opening, 3; verbal answer, 4; motor response, 6), with a body emperature of 40.4°C. Physical examination showed severe tenerness in the right lower quadrant of the abdomen. Laboratory ests on admission showed low serum albumin (2.3 g/dL) and levated C-reactive protein (28.86 mg/dL). The patient tested negtive for human immunodeficiency virus infection, syphilis, and epatitis B virus infection. Computed tomography showed edematous, diffuse wall thickenng of the right-sided colon (Figure A, arrows). Colonoscopy showed a eep, irregular, and completely circumferential ulcer with exudates at he cecum (Figure B) and multiple annular ulcers from the ascending o the descending colon. A biopsy and aspiration of intestinal fluid rom the lesions were then performed endoscopically. The biopsy pecimen revealed trophozoites of Entamoeba histolytica ingesting rythrocytes (HE Figure C, arrows). Negative results for intesinal fluid cultures for bacterial species or acid-fast bacilli were conrmed. The patient tested positive for serum antiamebic antibody at titer of 200. On the basis of these examinations, the final diagnosis as amebic colitis. Treatment with metronidazole 750 mg/day was tarted. After 2 weeks of treatment, the patient’s clinical symptoms mproved greatly, and colonoscopy showed ulcer scar. Amebiasis is caused by the protozoan Entamoeba histolytica. Each ear, this disease develops worldwide in 40–50 million persons and auses 40,000 deaths.1 Although Japan is a nonendemic country, mebic colitis is emerging as a sexually transmitted disease.2 The risk actors for amebiasis have been reported as a history of syphilis, uman immunodeficiency virus infection, and contact with men who ave sex with men or commercial sex workers.2 Watery or bloody diarrhea with abdominal pain is a typical clinical presentation.3 In this ase, because the patient had no risk factors and the clinical presenation was atypical, amebic colitis was not initially suspected. We previously reported4 that the typical endoscopic findings of mebic colitis were the presence of cecal lesions, multiple lesions, and xudates. Indeed, the present patient had multiple ulcers with exuates from the cecum to the descending colon. Fulminant amebic olitis is a rare disease with high morbidity and mortality, which is sually diagnosed on the basis of a resected specimen or autopsy,5 but in this case, endoscopy with biopsy and early treatment with metronidazole avoided serious complications such as perforation and toxic megacolon. Endoscopy with biopsy is useful for diagnosing fulminant amebic colitis, and early administration of metronidazole can improve clinical outcomes.