Legionnaires' disease. Clinical and pathologic features and current management.

"New" diseases continue to crop up. One of the most spectacular of these is Legionnaires' disease, first diagnosed after an epidemic in Philadelphia in 1976. Analysis of stored serums, however, has shown the causative agent, Legionella pneumophila, to be the culprit in epidemics of pneumonia occurring as early as 1947. The disease has a spectrum of presentations ranging from a self-limited syndrome of myalgias and nonproductive cough with a 24-hour incubation period to a severe pneumonia with diarrhea and delirium and up to 30% mortality. Therapy consists of erythromycin with or without rifampin. One reviewer said, "I found Dr Francke's article . . . to be an informative treatise on a fascinating subject."