Peripartum bacteremia in the era of group B streptococcus prophylaxis.

OBJECTIVE: To define the microbial epidemiology and clinical risk factors associated with peripartum bacteremia in the era of group B streptococcus prophylaxis.

METHODS: We identified all cases of maternal bacteremia occurring during the peripartum time period (defined as from 7 days before delivery until 30 days after delivery) in a large maternity center from 2000 to 2008. Chart review was performed to determine the clinical factors associated with bacteremia.

RESULTS: During the study period, blood cultures were obtained from 1,295 febrile peripartum women (1.6% of all parturients); 172 of 1,295 febrile peripartum women (13.3%) had bacteremia (2.2 cases per 1,000 deliveries) with 194 microbial isolates and 1 yeast. The most frequent bacterial isolates were Escherichia coli (35.9%), enterococci (23.6%), and anaerobic species (9.2%); group B streptococcus was isolated in only eight cases (4.1%). Clinical diagnoses among infected women included endometritis (56%), chorioamnionitis (21%), and urosepsis (8%). Among women with endometritis, 77% underwent cesarean delivery (compared with vaginal delivery; relative risk [RR] 10.85, 95% confidence interval [CI] 6.75-17.45) and 39% delivered at less than 37 weeks of gestation (compared with 37 weeks or more; RR 3.21, 95% CI 2.42-4.25). Severe maternal complications of bacteremia were noted; six women required intensive care unit admission, five women had development of ileus, and one death occurred because of urosepsis.

CONCLUSION: In the era of group B streptococcus prophylaxis, E coli and enterococci are the most frequent bacteria isolated in peripartum bacteremia. Group B streptococcus accounted for only 4% of cases.

LEVEL OF EVIDENCE: III.