Legionnaires' Disease: Diagnosis and Management

Abstract

Legionnaires' disease, an acute bacterial infection commonly manifested as pneumonia, has recently been recognized in outbreaks and sporadic cases. Most documented cases have occurred during the summer and in middle-aged or older persons. Clues to the diagnosis include nonproductive cough, pleuritic chest pain, diarrhea, and confusion. Moderate leukocytosis and nodular consolidation typically are seen on chest roentgenograms. Diagnosis may be made by culture of the fastidious Gram-negative bacillus from lung tissue or pleural fluid, demonstration of the organism in lung tissue by the direct fluorescent antibody technique, or documentation of a significant rise in serum titer by indirect fluorescence. Erythromycin is recommended for therapy.