Cytomegalovirus Colitis in Adult Patients with Inflammatory Bowel Disease.

Cytomegalovirus (CMV) colitis, a complication in patients with inflammatory bowel disease (IBD), particularly ulcerative colitis (UC), is a significant diagnostic and therapeutic challenge due to its overlap with IBD flares. CMV reactivation in IBD is driven by chronic inflammation, compromised immune function, and use of immunosuppressive agents like corticosteroids. Risk factors include older age, pancolitis, and severe disease. Diagnosis hinges on endoscopy and histology, with tissue biopsy and immunohistochemistry as the gold standard. Quantitative tissue PCR may aid in differentiating latent from active infection. CMV colitis exacerbates IBD symptoms, prolongs hospitalization, and increases colectomy rates. Antiviral therapy, primarily ganciclovir, improves outcomes in patients with corticosteroid-refractory UC. Treatment focuses on tapering corticosteroids, optimizing biologic therapies such as infliximab, and a careful application of antivirals tailored to disease severity and viral load. Further research is needed to refine diagnostic thresholds and treatment strategies to mitigate CMV's impact on IBD prognosis. Early identification and individualized management are critical to improving clinical outcomes and reducing morbidity.