Diagnostic yield from colon biopsies in patients with inflammatory bowel disease and suspected cytomegalovirus infection: is it worth it?

Background: Patients with inflammatory bowel disease (IBD) are often immunosuppressed and are at risk for reactivation of latent cytomegalovirus (CMV) infection. We examined the diagnostic yield from colon biopsies in IBD patients with suspected CMV infection.

Methods: Patients above 18 years of age who underwent testing for CMV on colon biopsies between January 1st, 2012, and December 31st, 2015, were identified from a pathology data base. A positive CMV result was included only if testing included both hematoxylin/eosin staining and immunohistochemistry from two or more biopsy samples.

Results: One hundred twenty-five patients met the inclusion criteria. Of these, 99 had a diagnosis of IBD: 30 with Crohn's disease, 63 with ulcerative colitis, and 6 with indeterminate colitis. As regards treatment, 21.2% of the patients had biologic therapy alone, 13.1% received immunomodulators, and 11.1% were treated with combined biologic and immunomodulator therapy within 3 months of the colon biopsy. In addition, 32.3% of the patients were on steroids. Of the 99 IBD patients, only 1 had biopsy-proven CMV colitis.

Conclusion: The yield from colon biopsies with hematoxylin/eosin staining and immunohistochemistry to test for CMV in IBD flare is very low. Further multicenter studies with large numbers of patients are needed to compare all testing modalities in the same cohort of patients. This may help identify which subgroup of IBD patients are likely to benefit from specific modalities of CMV testing, with potential cost-saving implications.