Impact of rifampicin addition to clarithromycin in Legionella pneumophila pneumonia.

We evaluated the effectiveness and safety of rifampicin addition to clarithromycin in the treatment of Legionnaires' disease. An observational cohort study was conducted on patients assigned to a Legionnaires' disease outbreak. Of 32 patients with confirmed Legionella pneumonia, 11 received clarithromycin monotherapy and 21 received combination therapy of clarithromycin with rifampicin.