Haemophagocytic lymphohistiocytosis following culture-proven pneumococcal infective endocarditis of the tricuspid valve

We report a case of a 2-year-old boy presenting with persistent fever and splenomegaly who fulfilled the diagnostic criteria for haemophagocytic lymphohistiocytosis (HLH) according to the Histiocyte Society (2004). The persistence of a cardiac murmur despite multiple transfusions, and therapy which rendered him afebrile, led us to do an echocardiogram as part of surveillance for sepsis. This revealed tricuspid vegetation and a small ventricular septal defect. Blood culture and postoperative histology of the anterior leaflet of the tricuspid valve confirmed Streptococcus pneumoniae infection. The patient was successfully treated with intravenous antibiotic therapy for 6 weeks and dexamethasone for 8 weeks and remains well and in remission (from HLH) a year later with residual tricuspid regurgitation awaiting tricuspid valve replacement.