S5096 A Gut Feeling Gone Wrong: Unmasking CMV Colitis in IBD Flare

Introduction: Cytomegalovirus (CMV) colitis is an acute systemic infection involving the large intestine. Following primary infection, CMV can persist in a latent form capable of reactivation. In the immunocompromised population, CMV infection has been seen in patients undergoing hematopoietic stem cell transplantation, acquired immunodeficiency syndrome, and chemotherapy or corticosteroid therapy. Studies suggest CMV colitis superimposed on inflammatory bowel disease (IBD) is associated with worse clinical outcomes. We present the case of a 56-year-old man who presented with hematochezia and was diagnosed with ulcerative pancolitis with superimposed CMV infection. Case Description/Methods: A 56-year-old incarcerated man with a past medical history of iron deficiency anemia presented with bloody diarrhea. He reported a 3-month history of scant hematochezia and a 40-pound unintentional weight loss. Labs showed leukocytosis of 12.55, hemoglobin of 10.7, platelet count of 840, and C-reactive protein of 45.9. Infectious stool studies were negative. Computed tomography (CT) abdomen and pelvis revealed protocolitis. Esophagogastroduodenoscopy and colonoscopy confirmed protocolitis along with suspicion for ulcerative colitis (UC). Empiric treatment with intravenous steroid, azathioprine, and mescaline were initiated. He was stabilized and discharged back to jail. He returned 24 hours later after pathology confirmed concomitant CMV colitis. Due to concerns for disseminated CMV, immunosuppressants were discontinued and ganciclovir was started empirically. CMV serology was positive for IgM and IgG; polymerase chain reaction showed 2,490 IU/mL. Discontinuation of IBD therapy resulted in IBD flare with worsening hematochezia and abdominal pain. Ganciclovir monotherapy was partially effective, prompting reintroduction of steroids and azathioprine. Infliximab was withheld due to concerns of antibody formation and lack of reliable outpatient follow-up due to incarceration. Once stabilized he was given a 10-day course of ganciclovir alongside his IBD regimen. Discussion: The prognosis of CMV colitis varies widely and studies suggest that CMV colitis superimposed on UC is associated with worse clinical outcomes, including higher rates of hospitalization, colectomy, and treatment failure. The use of corticosteroids and other immunomodulators, while necessary for controlling IBD flares, can promote viral reactivation by impairing T-cell mediated immunity. This case emphasizes the fragile balancing act required: treating the viral infection enough to control CMV without undermining the control of IBD activity.