Cytomegalovirus Infection in Patients with Active Inflammatory Bowel Disease

Background The reported prevalence of cytomegalovirus (CMV) infection with active inflammatory bowel disease (IBD) is highly variable, and whether CMV negatively impacts the clinical course is controversial. Aims The aim of this study was to determine the prevalence of CMV in patients with active ulcerative colitis (UC) or Crohn's disease (CD) and compare the course of disease in patients with and without CMV. Methods Consecutive patients with acute exacerbations of active IBD colitis had immunohistochemistry staining for CMV antigen performed on archived specimens. Clinical features were retrospectively reviewed. Results Twelve (10%) of 122 UC patients had CMV, and 0/20 patients with CD had CMV. Of 12 UC patients with CMV infection, seven were not taking steroids or immunosuppressives at their index flare. UC patients with CMV were more likely to have leukocytosis (OR = 5.3, 95% CI 1.5-18.2), require hospitalization (OR = 4.9, 95% CI 1.2-19.0), and be hospitalized >= 7 days (OR = 5.0, 95% CI 1.6-21.3) compared to patients without CMV. Of 12 UC patients with CMV, ten (83%) were treated for their index flare with steroids or 6-mercaptopurine. Only one patient (8%) was treated for CMV infection which occurred 14 months after index endoscopy. Over the 6 months after the index flare, UC patients with CMV had a higher frequency of IBD-related hospitalizations compared to patients without CMV (50 vs. 24%, P = 0.021), but none required surgery or died. Conclusions The prevalence of CMV with active UC was 10%. Although CMV infection may be a marker of disease severity, our results suggest it does not cause severe morbidity or mortality in a general population of patients with a UC flare.