Echovirus 18 Infection Is Associated with Crohn’s Disease

Background: Enterovirus (EV) can cause gastroenteritis and are known to replicate in Peyer’s patches of terminal ileum. EV has been found in the intestinal specimens from immunocompromised patients with regional enteritis, and another study demonstrates the presence of enterovirus in the resected terminal ileum of immunocompetent pediatric patients with Crohn’s disease (CD). Cluster outbreaks of CD have also been reported in the literature but the cause of the disease remains elusive. Materials and Methods: A small cluster of pathologically proven CD occurred in our geographic area in 2004-2005, concurrently with an epidemic of Echovirus 18 (E18) meningitis. Serum samples of these and other CD patients and control subjects were tested for neutralizing antibodies of 11 common typeable enteroviruses and Echovirus 18; and tissue samples of CD patients, and terminal ileum and colon biopsies of normal controls were tested for the presence of viral capsid protein 1 (VP1) by immunoperoxidase staining. Results: Immunoperoxidase staining demonstrated VP1 in a rare epithelial granuloma, in diseased muscle of terminal ileum and also in colon biopsies of CD patients. Significantly elevated E18 neutralizing antibody was found in patients with pathologically-proven Crohn’s disease, as compared to control subjects. Conclusion: In this small observational study, EV VP1 is consistently demonstrated in tissue samples of CD patients as compared to control subjects; and neutralizing antibody for E18 was found in all of the patients with available serum samples. Larger cross-sectional studies will be needed to define the role of E18 in this chronic disease.