[Chronic active Epstein-Barr virus infection in the gastrointestinal tract: a clinicopathological study of three cases].

ABSTRACT

Objective: To study the clinicopathological features of chronic active Epstein-Barr virus infection (CAEBV) in the digestive tract and to discuss its differential diagnosis. Methods: The clinical data of 3 cases of CAEBV in the digestive tract diagnosed in Jiangsu Province Hospital (the First Affiliated Hospital of Nanjing Medical University), Nanjing, China from December 2018 to August 2020 were collected. Three cases of CAEBV were evaluated using histology, immunohistochemistry and in situ hybridization. The related literature was reviewed. Results: Three patients were all males, aged 33, 32 and 31 years, respectively. All patients had a history of intermittent fever and repeated diarrhea for the past years with persistent increase in EB viral load (DNA copies) in peripheral blood. Endoscopically, intestinal tract was involved in all cases with ulcers, and esophagus was involved concurrently in 1 case showing nodular lesions. Microscopically, there were moderate polymorphic inflammatory infiltrate with lymphoid component displaying no or mild atypia in all cases and deep fissuring ulcers in one case (case 3). All tumor cells were positive for CD3 and TIA-1, and negative for CD56 and CD5. Cases 1 and 2 showed CD4-/CD8-, whereas case 3 displayed CD4+/CD8-. In situ hybridization for Epstein-Barr virus-encoded RNA was positive in all 3 cases. Follow-up data showed that cases 1 and 2 were free of disease progression at the end of follow-up (16 months and 17 months, respectively). However, case 3 progressed to extranodal NK/T-cell lymphoma 22 months after the initial diagnosis. Conclusions: CAEBV of the digestive tract is a rare lymphoid proliferative disorder with potential transformation to extranodal NK/T-cell lymphoma. It is a great mimicker of inflammatory bowel disease, especially in small biopsy specimens. It is important to integrate clinicopathological, radiological and laboratory data to avoid misdiagnosis.