Familial hemophagocytic lymphohistiocytosis with Epstein–Barr virus infection and progression to aggressive NK-cell leukemia: a case report and review of the literature

Familial hemophagocytic lymphohistiocytosis (FHLH) with Epstein–Barr virus (EBV) infection can mimic chronic active EBV infection of T- and NK-cell type (CAEBV-T/NK) in its clinical manifestation and pathomorphology. FHLH with genetic susceptibility to EBV has not been previously reported. The development of FHLH in conjunction with EBV infection is rare and needs further investigation to understand and characterize it. We report a rare case of FHLH with EBV infection that mimicked CAEBV-T/NK, but progressed to childhood aggressive natural killer cell leukemia (ANKL). The patient is in clinical remission following allogeneic hematopoietic stem cell transplantation (allo-HSCT). Our reported case suggests that patients with FHLH and EBV infection, especially those with symptoms similar to those of CAEBV-T/NK, may rapidly progress to ANKL or other neoplastic diseases. Therefore, we must be aware of these cases to ensure that patients are diagnosed correctly so they can be treated appropriately and in a timely manner.