A case report of an asymptomatic cecum ulceration colonoscopically and radiologically mimicking inflammatory bowel disease caused by amoebic colitis

Background: Amebiasis is a disease caused by the protozoan parasite Entamoeba histolytica (Eh) and remains the second leading cause of death due to parasitic infections worldwide. Asymptomatic Eh infections are the most common. Infection with Eh can transition from a harmless colonic colonizer to a pathogenic form, leading to amoebic colitis. The clinical presentation of amoebic colitis is varied and may include abdominal pain, bloody-mucoid diarrhea, tenesmus, and low-grade fever. These symptoms are often nonspecific and can mimic many other gastrointestinal conditions, both infectious and noninfectious. Case Description: We report a case of amoebic colitis in a 62-year-old male who underwent routine colonoscopy, which revealed an ulceration in the cecum region. He was asymptomatic at presentation and had normal laboratory findings. The case was provisionally diagnosed as inflammatory bowel disease (IBD) and received oral metronidazole and probiotics. At follow-up endoscopy the ulceration had worsened. Biopsy from the margin of the ileocecal ulcer confirmed abundant amoebic trophozoites. The patient was treated with metronidazole for 14 days. A follow-up colonoscopy after treatment showed that the lesions were completely healed. Conclusions: This case highlights the challenges of diagnosing amoebic colitis. Amoebic colitis shows significant variation in presenting symptoms and current diagnostic methods have limited sensitivity. The absence of obvious symptoms in this patient further increased the diagnostic difficulty. We recommend that clinicians consider invasive amoebiasis in their list of differential diagnosis even in asymptomatic patients presenting with colonic ulceration.