Nocardia infection

A 43-year-old man who, after bone marrow transplantation for acute leukemia, developed fever and dyspnea with a clear chest radiograph while neutropenic. Following bone marrow engraftment (absolute neutrophil count >500/mm³), an infiltrate appeared on chest radiograph (panel A), which was more apparent by chest computed tomography (panel B). Cultures revealed Nocardia asteroides.