An investigation of enterococcal bacteremia

Records of all 34 patients with positive blood cultures for enterococcus at Mount Sinai Medical Center of Greater Miami in 1981 were reviewed. Twenty-four true bacteremias were identified from sources including the pelvis/abdomen (9), urinary tract (6), wounds (2), IV catheter (2), contaminated needle (1), endocarditis (1), and primary bacteremia (3). Sixteen of the 24 true bacteremias were hospital acquired, and these infections accounted for 7 of 9 (78%) fatal outcomes. Fourteen of 16 patients with hospital-acquired infection received prior antibiotic therapy. Eight (24%) of the original 34 patients had positive blood cultures for enterococcus as a result of cross-contamination from an automated blood culture analyzer. The rate of cross-contamination per positive blood culture for enterococcus in 1981 was 22%. Two remaining patients in the original series could not be placed in a category of true infection or cross-contaminant. Although there was a real increase in the number of enterococcal bacteremias in 1981, a much larger apparent increase was explained by several episodes of pseudobacteremia.