Viral DNA in inflammatory bowel disease. CMV-bearing cells as a target for immune-mediated enterocytolysis.

Althouth serological studies have revealed a high incidence and mean titer of antibody to cytomegalovirus (CMV) in some patients with inflammatory bowel disease, electron microscopy has not confirmed the presence of mature virus in diseased tissue. Sensitive biochemical techniques for detection of viral nucleic acid were applied therefore to test the proposed disease-virus association. Membrane cRNA-DNA hybridization showed that CMV DNA was not detectable in 3 cases of Crohn's disease, nor was it present in 3 or 4 cases of ulcerative colitis examined. Five tissue specimens taken 5 cm away from a colonic tumor were also negative. An in situ hybridization study of diseased tissue, including specimens from 6 inflammatory bowel disease patients in addition to those above, showed a few grains distributed over cells superficial to the muscularis mucosa, but was not regarded as significantly different from controls. The association of CMV with Crohn's disease (0 positives in 4 patients by either test) is not supported by this study; the association with ulcerative colitis (1 positive in 9 patients by either test) requires further study before a definitive conclusion can be made.