Group b Streptococcal pneumonia in the elderly.

Group B streptococcal infections, although well studied in neonates, have only recently been appreciated as important infectious agents in adults. Seven cases of Group B streptococcal pneumonia were verified by transtracheal aspiration, blood and sputum cultures, or multiple stab cultures at autopsy. The infections were largely nosocomial and, ultimately, fatal in all seven patients. Our patients were older (average age, 73 years) and much more debilitated than the 13 cases reported in the literature. Diabetes was less common than previously reported. Previous antibiotic therapy was common. Concomitant isolation of another organism (especially Staphylococcus aureus) occurred in five patients. The morphologic findings at autopsy, in one patient, were characterized by a severely necrotizing destructive process. In our experience, Group B streptococcal pneumonia is more common, more devastating, and occurs in an older population than previously reported.