[Observation on clinical features and therapy in 4 elderly cases with legionellosis].

Four elderly cases with Legionellosis were reported. All of them had pneumonitis and small amount of chest fluid. Erythromycin and rifadin were effective in all 4 patients. Three patients were positive for Legionella pneumophila serogroup 1. The disease occurred in July or October. Diagnosis and therapy should be made as early as possible for those patients suspected of Legionellosis.