Failure of erythromycin in treatment of Legionella micdadei pneumonia.

A 59-year-old immunocompromised woman had nosocomial Legionella micdadei infection that failed to respond to two weeks of erythromycin in high intravenous doses and oral rifampin. Treatment with intravenous trimethoprim-sulfamethoxazole and oral rifampin, which previously has not been used in this infection, resulted in cure.