Clinicopathological characteristics of a rare group of chronic active Epstein-Barr virus disease involving the gastrointestinal tract.

backgroundGastrointestinal involvement in chronic active Epstein-Barr virus disease (CAEBVD) is rare, and no large-scale case series has been reported in the literature to date. Due to lack of specific clinicopathological manifestations, this disease is prone to being missed or misdiagnosed as other intestinal disorders. The aim of our study was to describe the clinicopathological features of this disease and identify the key diagnostic and differential diagnostic criteria, in order to facilitate accurate and timely diagnosis and effective treatment.

methodsWe retrospectively analysed 44 cases of CAEBVD with gastrointestinal involvement. We summarised the clinicopathological and molecular genetic characteristics of these cases using immunohistochemical staining, EBER in situ hybridisation, double-labelling staining, and TCR gene rearrangement.

resultsTwenty-six cases were male and 18 were female. Their mean age was 27 years, and the mean disease duration was 15 months. The main manifestations were abdominal pain and diarrhoea (75%), fever (68.2%), splenomegaly (88.6%), lymphadenopathy (59.1%), hepatomegaly (38.6%), and anaemia (72.7%). Most cases (88.6%) presented with erythema, erosion, or superficial ulcers characterised by multiple small lesions. The lesions were primarily confined to the mucosal layer. The tumour cells were mainly small to medium in size, with mild to moderate nuclear irregularity. All cases tested positive for CD3, with CD5 antigen loss observed in 45.5% of cases, and most cases (76.9%) predominantly exhibited CD4-positive T cells. Some cases (31.8%) were positive for CD56. All cases were EBER-positive, with 20-200 positive cells per high-power field. The majority of cases (77.3%) were T-cell infections. Six out of ten showed TCR monoclonal rearrangement. Of the 39 cases, a total of 20 (51.3%) died, with a mean survival time of 5.9 months. Patients who received allogeneic haematopoietic stem cell transplantation (allo-HSCT) had a survival rate of 76.5%.

conclusionsThese findings indicate that gastrointestinal CAEBVD lacks distinctive clinical and pathological characteristics, and peripheral blood EBV DNA screening combined with EBER detection of biopsy tissues is the most important factor in avoiding misdiagnosis and underdiagnosis. Gastrointestinal CAEBVD carries a poor prognosis, but allo-HSCT can significantly increase patient survival rates.