Bacteremia and septicemia due to anaerobic bacteria in newborns

Abstract

The awareness of the role of anaerobic bacteria in neonatal bacteremia and sepsis has increased in recent years. The incidence of recovery of anaerobes in neonatal bacteremia varies between 1.8% and 12.5%. Of the 179 cases reported in the literature, 73 were due to Bacteroides spp. (69 were the Bacteroides fragilis group), 57 Clostridium spp. (mostly Clostridium perfringens), 35 Peptostreptococus spp., 5 Propionibacterium acnes, 3 Veillonella spp., 3 Fusobacterium spp, and 2 Eubacterium spp. Predisposing factors were perinatal maternal complications (especially premature rupture of membranes and chorioamnionitis), scalp abscess, prematurity, and necrotizing enterocolitis. Organisms similar to those isolated in blood were concomitantly recovered in lung aspirates and cerebrospinal and peritoneal fluids. The overall mortality noted is 26% and is highest with B. fragilis group (34%). Inappropriate choice of antimicrobial therapy was often a contributory factor to mortality. Correction of underlying pathology, surgical drainage, and the use of proper antimicrobials are critical to successful resolution of the infection. Penicillin G is the drug of choice for anaerobic infection other than one due to beta-lactamase-producing anaerobic Gram negative bacilli. Antimicrobials useful for therapy these organisms include clindamycin, metronidazole, chloramphenicol, a carbapenem, and the combination of a penicillin plus a beta-lactamase inhibitor.