Epidemiology of community-acquired bacteremia among infants in a medical center in Taiwan, 2002–2011

ObjectiveTo investigate the etiologies and antibiotic susceptibility of community-acquired bacteremia in infants in a medical center in northern Taiwan.MethodsWe conducted a retrospective analysis of all blood cultures from infants in the National Taiwan University Hospital from 2002 to 2011 to find community-acquired bacteremia. Common pathogens, antibiotic resistance, and outcome were analyzed.ResultsDuring the study period, 25,628 blood cultures were collected, and 3.4% of the cultures were positive, of which 15.9% were categorized as community-acquired bacteremia. In the age group of 0–6-days, the leading causative organisms were group B streptococcus (41.7%) and Escherichia coli (30.6%). In the 7–90-days and 4–6-months groups, the most common pathogens were E. coli (44.1%, 45.5%, respectively) and group B streptococcus (32.4%, 13.6%, respectively). For infants aged 7–12 months, the most common pathogens were Salmonella species (51.1%) and E. coli (12.8%). The overall mortality rate of community-acquired bacteremia was 6%. Urinary tract infection was the concomitant diagnosis among 52.4% of infants with E. coli bacteremia. Meningitis was found in 33.3% of infants with group B streptococcus bacteremia. Listeria monocytogenes bacteremia was identified in three infants, one of whom had meningitis. Penicillin resistance was found in 4% of group B streptococcus and ampicillin resistance in 71% of E. coli.ConclusionOur study provides updated etiological data on community-acquired bacteremia in infants in northern Taiwan. Group B streptococcus and E. coli remained the leading pathogens in infants aged 6 months or younger and Salmonella species for those older than 6 months.