Streptococcus mitis. A cause of serious infection in adults

Abstract

Twenty strains of Streptococcus mitis were isolated from blood or body fluids at the Cleveland [Ohio, USA] Veterans Administration Medical Center from Jan 1, 1981, to April 30, 1984. Fifteen (75%) isolates were considered contaminants. Five (25%) were clinically important and associated with a serious infection of the oropharynx or gastrointestinal tract (three of five), endovascular system (one of five), or a prosthetic hip. Four of five patients required surgical intervention for treatment. Two of five died; one death was directly attributable to S. mitis infection. Eighteen strains were available for detailed bacteriologic study. THree strains had a minimum inhibitory concentration of greater than 0.1 .mu.g/mL of penicillin and six other strains were tolerant to penicillin. THis review suggests that S. mitis can be an important pathogen in adults and may cause infections other than endocarditis.