Successful treatment of secondary hemophagocytic lymphohistiocytosis in a patient with disseminated histoplasmosis.

Hemophagocytic lymphohistiocytosis (HLH) is an overwhelming inflammatory response, associated with an outpouring of cytokines and inappropriate activation of the macrophage system, causing severe morbidity and possible death. HLH has inherited and acquired forms. Secondary HLH can be related to any number of underlying conditions including infections, malignancy and autoimmune diseases. There are similarities between "cytokine storm" seen in HLH and the clinical findings of avian influenza. We report a patient with a history of sarcoidosis on chronic steroid treatment, who developed HLH secondary to an infection with Histoplasma capsulatum.