Epstein-Barr virus infection is an independent risk factor for surgery in patients with moderate-to-severe ulcerative colitis.

Background: Epstein-Barr virus (EBV) infection of the intestinal mucosa is associated with surgical risk in ulcerative colitis (UC); however, the exact effect remains unclear.

Aim: To determine whether EBV infection can predict the need for colectomy and to develop a surgical risk predictive model.

Methods: This was a single-center retrospective study of 153 patients with moderate-to-severe UC between September 2012 and May 2023. EBV-encoded small RNA (EBER) in situ hybridization and immunohistochemistry (IHC) were used for EBV testing and assessment. Cytomegalovirus (CMV) was detected by IHC. Logistic regression analysis was conducted to identify risk factors for colectomy and develop a predictive risk model.

Results: EBER-positivity in the intestinal mucosa was present in 40.4% (19/47) and 4.7% (5/106) of patients in the surgery and non-surgery groups, respectively, with significant differences between the groups (P < 0.01, odds ratio = 13.707). The result of multivariate logistic regression revealed that age, EBV infection in the colonic mucosa, CMV infection in the colonic mucosa, and treatment with three or more immunosuppressive agents before admission were significant independent predictors of colectomy. A nomogram incorporating these variables demonstrated good discriminative ability, and exhibited good calibration and clinical utility. IHC showed that EBV-infected cells mainly included B and T lymphocytes in patients with high EBER concentrations.

Conclusion: EBV infection of the intestinal mucosa is a significant independent risk factor for colectomy in patients with moderate-to-severe UC. The nomogram model, which includes EBV infection, effectively predicts colectomy risk.