A Boy with Chronic Active EBV Infection Presented as Mosquito Bite Hypersensitivity Progressed to Fatal Hemophagocytic Lymphohistiocytosis due to NK Cell Neoplasm / 임상소아혈액종양

Chronic active Epstein-Barr virus (CAEBV) infection is characterized by recurrent infectious mononucleosis (IM)-like symptoms and an unusual pattern of anti-EBV antibodies. We report a boy with CAEBV who progressed to aggressive hemophagocytic lymphohistiocytosis (HLH) with NK cell neoplasm. A 19-year-old adolescent boy was admitted with fever and a history of recurrent IM-like symptoms following mosquito bites since the age of 6 years. His condition was diagnosed as CAEBV with atypical lymphocytosis and an unusual pattern of anti-EBV antibodies. His symptoms subsided during treatment with steroids and cyclosporine, although the EBV genome load kept increasing for several years. He was re-admitted after follow-up loss for 8 years, and his clinical and laboratory findings confirmed HLH and high titer of the EBV genome. Bone marrow analysis with flow cytometry showed hemophagocytosis with compatible NK cell neoplasm. He rapidly progressed to pulmonary infection and expired soon after. We conclude that hematopoietic stem cell transplantation may be a potential therapeutic modality for treating CAEBV before serious EBV manifestations.

Chronic active EBV infection: the experience of the Samsung Medical Center in South Korea / Infección crónica activa por virus de Epstein-Barr: experiencia del Centro Médico Samsung en Corea del Sur

Abstract Background: Chronic active EBV infection (CAEBV) of T-cell or NK-cell type is an EBV+ polyclonal, oligoclonal or often monoclonal lymphoproliferative disorder (LPD) recognized as representing the spectrum of EBV-associated T-cell and NK-cell LPD with different clinical presentations; one systemic and two cutaneous disorders including hydroa vacciniforme-like T-cell LPD and mosquito bite hypersensitivity. The systemic form of the disease is characterized by fever, persistent hepatitis, hepatosplenomegaly and lymphadenopathy, which shows varying degrees of clinical severity depending on the immune response of the host and the EBV viral load. Case reports: We described the clinicopathological findings of two children with CAEBV with a brief review of the literature. Conclusions: Recognition of the disease is important for adequate management of the patient. EBV analysis should be included in the principal diagnostic tests for febrile children.

Resumen Introducción: La infección crónica activa (CA) de células T o células tipo NK por virus de Epstein-Barr (VEB) es un desorden linfoproliferativo (DLP) VEB+ policlonal, oligoclonal o, frecuentemente, monoclonal reconocido como representación del espectro del DLP de células T y células NK asociado con VEB que tiene diversas presentaciones clínicas: un padecimiento sistémico y dos cutáneos que incluyen el DLP de células T que semeja hidroa vacciniforme y la hipersensibilidad por picadura de mosquito. Los síntomas de la enfermedad sistémica incluyen fiebre, hepatitis persistente, hepatoesplenomegalia y linfadenopatías que muestran diferente grado de severidad clínica, dependiendo de la respuesta inmune del hospedero y de la carga viral del VEB. Casos clínicos: Se describen los hallazgos clínico-patológicos de dos niños con CAVEB y una breve revisión de la literatura. Conclusiones: Es importante reconocer esta enfermedad para proporcionar el manejo adecuado al paciente. El análisis de VEB debería incluirse como una de las principales pruebas diagnósticas en niños con fiebre.