LAUSR

We present the case of a 7-year-old boy who fulfilled the diagnostic criteria for hemophagocytic lymphohistiocytosis (HLH). Prompt visualization of his bone marrow confirmed the diagnosis of visceral leishmaniasis (VL). He responded well to treatment with liposomal amphotericin-B. The patient had a false-negative enzyme-linked immunosorbent assay for Leishmania infantum and a false-positive immunoglobulin M test for Epstein Barr virus (EBV). Because age at presentation is similar in children with VL and familial HLH for whom EBV is the usual trigger, ruling out VL is extremely important because nonspecific serologic tests for EBV can lead to the inappropriate diagnosis of EBV-driven primary HLH and to the administration of unnecessary immunochemotherapy.