Non-systemic Epstein-Barr virus infection in patients with ulcerative colitis

Abstract Background: The potential role of EBV infection in ulcerative colitis (UC) patients has not been fully elucidated yet, therefore we aimed to study it further. Methods: 59 biopsy stecimens and 20 surgical specimens of ulcerative colitis were included in the study. 59 biopsy stecimens were from 18 non-refractory UC patients and 41 refractory UC patients who received steroids therapy. EBV-encoded small RNA (EBER) in situ hybridization (ISH) was performed for the virus detection. The corresponding electronic medical records were reviewed to analysis the clinical characteristics. Results: EBER nuclear expression in biopsy spesimens of non- refractory UC patients and refractory UC patients was 16.7% (3/18) and 9.76% (4/41) respectively, showing no significant differences between the two groups. EBER nuclear expression in surgical specimens of ulcerative colitis were much higher (80%) than in biopsy spesimens. However, EBER positive cells in most samples of UC patients were less than 50 per high-power field. No systemic symptoms of EBV infection were found in UC patients. The 5-year survival rate of UC patients who underwent surgery was 100%. Conclusions: UC patients with EBV infection showed limited systemic active EBV infectious symptoms. EBV infection did not worsen the prognosis of UC patients.