Cytomegalovirus Colitis in Inflammatory Bowel Disease The Eternal Debate: Foe or Innocent Bystander?

Key Takeaways: • The prevalence of CMV infection among patients with IBD ranges from 2 to 29%, with a higher prevalence in those with UC compared to CD. • Immunohistochemistry and tissue PCR, or both, are the recommended tests for diagnosing active CMV colitis. • CMV may be an active pathogenic participant in cases with a high density of CMV and severe disease activity. Thus, we recommend testing for CMV colitis in patients with a severe inflammatory burden who are not responding to conventional IBD therapy. • Patients with low CMV viral burden can likely be treated with immunosuppression alone, while patients with high viral density or medically refractory disease should be treated with antiviral therapy.