Case of Chronic Active Epstein-Barr Virus Infection Developed Hemophagocytic Lymphohistiocytosis after COVID-19 Infection

In children, prolonged primary Epstein-Barr virus (EBV) infection or reactivation may lead to the development of T or natural killer cell lymphoproliferative disorders, classified as chronic active EBV infection (CAEBV). CAEBV is a prolonged systemic illness lasting beyond three months, with elevated EBV DNA levels in the serum or affected tissue and a lack of underlying immunodeficiency. Notably, EBV is the most common virus that induces secondary hemophagocytic lymphohistiocytosis (HLH), and Coronavirus disease 2019 (COVID-19) has been reported to trigger HLH. We present the case of a 20-year-old Korean male who was diagnosed with CAEBV and developed HLH after being infected with COVID-19. The patient met 7 out of 8 criteria for HLH. Following treatment with corticosteroids and intravenous immunoglobulin, the patient recovered from HLH without additional chemotherapy. HLH treatment should be tailored to each patient based on clinical presentation and disease severity. Prolonged and regular evaluation for developing HLH or lymphoma is necessary for patients with CAEBV.