Fatal murine typhus with hemophagocytic lymphohistiocytosis in a child.

Hemophagocytic lymphohistiocytosis is a rare complication in Rickettsia typhi infections. We report the case of a 2-year-old boy with sudden night-onset fever, pallor, neck adenopathy and erythematous macular rash on the thorax, thighs and buttocks. During admission, he developed hyponatremia, hypoalbuminemia, anemia, thrombocytopenia, leukopenia, neutropenia, liver damage, hemorrhages and persistent fever. No hematological improvement was observed after the initial management, neoplastic diseases were discarded by bone marrow aspiration and lymph node biopsy; hemophagocytic lymphohistiocytosis was diagnosed. By immunohistochemistry and indirect immunofluorescence, murine typhus was also diagnosed and doxycycline was started with transitory recovery. Later, the child developed kidney failure and distributive shock that evolved to cardiac arrest and death. This is the first case report in Mexico on a fatal murine typhus associated with hemophagocytic lymphohistiocytosis in which the etiology was evidenced by histopathology.