S5074 Triple Infection in an Immunosuppressed Host: CMV Colitis With Enteropathogenic E. coli Diarrhea and EBV Viremia

Introduction: Cytomegalovirus (CMV) is a significant complication in solid organ transplant recipients on immunosuppressive therapy. It can affect multiple organ systems, manifesting as colitis, hepatitis, retinitis, or disseminated disease. Prompt diagnosis and management are crucial to prevent poor outcomes. We present a complex case of CMV colitis in a kidney transplant recipient, complicated by concurrent enteropathogenic Escherichia coli (EPEC) diarrhea and Epstein–Barr virus (EBV) viremia. Case Description/Methods: A 68-year-old man with end-stage renal disease status post bilateral sequential kidney transplants, maintained on mycophenolate, belatacept, and low-dose steroids, presented with 5 days of non-bloody diarrhea and right upper quadrant pain. Laboratory evaluation showed elevated transaminases and CMV viremia exceeding 2,000,000 copies/mL. A GI multiplex panel detected EPEC. Initial imaging was unremarkable. On hospital day 4, he developed hemodynamically significant gastrointestinal bleeding. Colonoscopy revealed patchy erythema, and biopsies confirmed CMV pancolitis via immunohistochemical staining. EBV viremia was also detected, raising concern for post-transplant lymphoproliferative disorder (PTLD), although no lymphoproliferative lesions were found. Subsequently, the patient developed bilateral CMV retinitis. Treatment was initiated with intravenous ganciclovir due to the extent of viremia and tissue-invasive disease, later transitioning to oral valganciclovir. Belatacept was replaced with tacrolimus to reduce CMV risk. The patient improved with multidisciplinary care and was discharged with infectious disease follow-up. Discussion: This case highlights the challenges of managing cytomegalovirus (CMV) infection in immunosuppressed transplant recipients, especially with multiorgan involvement and coinfections. Although enteropathogenic E. coli (EPEC) was initially suspected, the high CMV viral load and biopsy-proven pancolitis indicated CMV as the primary cause of diarrhea. Epstein–Barr virus (EBV) viremia suggested over-immunosuppression and raised concern for post-transplant lymphoproliferative disorder. Given literature associating belatacept with higher CMV and EBV risk, it was replaced with tacrolimus. Multidisciplinary management, including ganciclovir therapy and immunosuppressive adjustment, led to clinical improvement. This case underscores the need for early detection and tailored treatment in complex post-transplant scenarios.