Fulminant amebic colitis in a patient with concomitant cytomegalovirus infection after systemic steroid therapy: A case report

BACKGROUND: Amebic colitis is an infection caused by Entamoeba histolytica and most commonly observed in regions with poor sanitation. It is also seen as a sexually transmitted disease in developed countries. While amebic colitis usually has a chronic course with repeated exacerbations and remissions, it may also manifest as a fulminant form that rapidly progresses and leads to severe, life-threatening complications, such as intestinal perforation, peritonitis, and sepsis, that have a high mortality rate. CASE SUMMARY: A 68-year-old man was admitted to our hospital with chest pain and acute dyspnea. He was diagnosed with acute coronary syndrome, acute heart failure, and bacterial pneumonia. His respiratory condition worsened despite receiving intensive care and intravenous antibiotics. On the fifth day of hospitalization, he was diagnosed with acute respiratory distress syndrome and was started on steroid therapy. He subsequently developed bloody stools and was diagnosed with cytomegalovirus (CMV) enterocolitis based on biopsy results and a peripheral blood CMV pp65 antigenemia test result. Although we started antiviral therapy with ganciclovir, which was successful in reducing his antigen titers, he continued to have bloody diarrhea. Three weeks after initiation of ganciclovir therapy and six weeks after his admission, the patient died from intestinal perforation. We only posthumously diagnosed him with amebic colitis and CMV enterocolitis based on autopsy findings of transmural necrosis of the entire colon with massive ameba infiltration. CONCLUSION: We urge clinicians to consider Entamoeba histolytica infection if severe colitis progresses after steroid therapy. Preemptive treatment is recommended then.