Byington, Carrie L., Rittichier, Kristine K., Bassett, Kathlene E., Castillo, Heidi, Glasgow, Tiffany S., Daly, Judy, and Pavia, Andrew T.
Background. Intrapartum antibiotic prophylaxis against group B Streptococcus (GBS) has reduced the occurrence of serious bacterial infections (SBI) in young infants caused by GBS. Recommendations for initial antibiotic therapy for the febrile infant 1 to 90 days old were developed when infections with GBS were common and antibiotic resistance was rare. Objective. To document the pathogens responsible for SBI in recent years in febrile infants 1 to 90 days old and the antibiotic susceptibility of these organisms. Methods. The results of bacterial cultures from infants 1 to 90 days old evaluated for fever at Primary Children's Medical Center in Salt Lake City, Utah, between July 1999 and April 2002 were analyzed. Antibiotic susceptibility profiles were collected and patient records were reviewed to determine if initial antibiotic therapy was changed following the identification of the organism. Results. Of 1298 febrile infants enrolled from the Primary Children's Medical Center emergency department, 105 (8%) had SBI. The mean age of the infants with SBI was 39 days (range 2-82 days) and 2 (2%) were Of the 105 pathogens, 56 (53%) were resistant to ampicillin. Of the pathogens causing meningitis, UTI, and bacteremia, 78%, 53%, and 50%, respectively, were resistant to ampicillin. Antibiotic therapy was changed in 54% of cases of SBI following identification of the organism. Conclusions. In Utah, ampicillin-resistant Gram-negative bacteria are the most common cause of SBI in febrile infants, ABBREVIATIONS. GBS, group B Streptococcus; SBI, serious bacterial infection; UTI, urinary tract infection; ESBL, extended spectrum [beta]-lactamases; ampC, ampC [beta]-lactamases; PCMC, Primary Children's Medical Center; ED, emergency department; CSF, cerebrospinal [...]