Intravenous ciprofloxacin versus erythromycin in the treatment of Legionella pneumonia

Background Erythromycin (EM) and rifampicin (RFP) have mainly been used to treat patients with Legionella pneumonia. Since intravenous ciprofloxacin (CPFX) became available in Japan from 2000, many reports have been published detailing successful treatment of Legionella pneumonia with CPFX. In this study, we compared the evolution of patients with Legionella pneumonia treated with CPFX to those treated with EM. Methods The study included nine patients treated with CPFX and eighteen patients treated with EM. Diagnosis of these patients was made by culture, PCR, urinary antigen assay or a serological method. A comparison was made of the patients' characteristics, severity of pneumonia, efficacy of each agent and the clinical course. Results No significant differences were observed between the two groups, in regard to age, gender, underlying disease or severity of pneumonia. In addition, the period of time from onset of the disease until appropriate therapy did not differ significantly between the two groups. In the CPFX group, all of the patients were cured and in the EM group 16 out of the 18 patients were cured. Although there were no significant differences, the time to apyrexia, normalization of leukocytosis and a 50% decrease in C-reactive protein (CRP) occurred within a relatively shorter time frame in the CPFX group than in the EM group (3.5 versus 4 days, 4 versus 5.2 days, and 2.9 versus 10.3 days, respectively). And, the duration of antibiotic treatment in the CPFX group was significantly shorter than in the EM group. Conclusion CPFX was as effective as erythromycin in the treatment of Legionella pneumonia. The effects of treatment may appear relatively earlier and the duration of treatment was significantly shorter in patients treated with CPFX therapy than with EM therapy.