Recurrent Legionnaires' disease: a case report.

In 1979, an isolated case of legionnaires' disease in a 46 year old Caucasian male Ohio physician was reported. Diagnosis was later confirmed by a fourfold increase in indirect immunofluorescent antibody titer level. Recovery began rapidly after the administration of erythromycin therapy and appeared to be complete. The following year the same patient suffered an apparent reinfection, once again realizing prompt and total recovery upon receiving erythromycin therapy. Although not commonly reported, the possibility of reinfection with the Legionella bacterium is a reality. The source of human innoculation need not necessarily be a common water supply or large cooling system reservoir (as was previously thought). Erythromycin continues to be widely regarded as the treatment of choice for infections with the Legionella bacterium even though this case demonstrates that it does not prevent reinfection.