Lethal pulmonary hemorrhage caused by a fulminant Stenotrophomonas maltophilia respiratory infection in an acute myeloid leukemia patient.

Stenotrophomonas maltophilia (Sm) pneumonia in immunocompromized hosts is an increasingly common nosocomial infection. Even though resistant to multiple antimicrobials, this gram-negative bacteria usually does not present with a fulminant course leading to a fatal hemorrhagic respiratory infection in neutropenic patients. We report here the case of a 63-year-old woman treated by intensive chemotherapy for acute myeloid leukemia (AML) who presented while severely neutropenic and thrombocytopenic a Sm pulmonary infection with hemoptysis leading to death in 48 h. The bronchoalveolar lavage (BAL) performed shortly before death was highly hemorrhagic and contained a striking amount of extra- and intra-cellular pathogens. Blood and BAL cultures grew S. maltophilia. Post-mortem examination revealed bilateral extensive intra-alveolar hemorrhage (IAH) associated with a great amount of microorganisms and severe bone marrow aplasia was observed without evidence of leukemia residual disease. Sm pneumonia usually does not evolve into such a devastating clinical picture although infections due to the bacteria are known to be associated with high morbidity and mortality. So far, the present observation is the fourth similar case reported in the literature. Even though an early diagnosis and an adequate antibiotic prescription may improve Sm infection prognosis, S. maltophilia proves difficult to eradicate due to a high resistance rate in part intrinsic but also in part acquired.