The association of intrapartum antibiotic exposure with the incidence and antibiotic resistance of infantile late-onset serious bacterial infections

Background. The widespread use of intrapartum antibiotics (IPA) has raised concerns regarding the adverse effects on the newborn. Objectives. To determine if IPA is associated with infantile late-onset serious bacterial infections (SBIs) and with antibiotic resistance. Patients and methods. From 2005 to 2009, data were prospectively collected for all infants born at our center, aged 7 to 90 days, who were hospitalized for fever. Cases included infants with culture-proven SBIs, and controls included infants without SBIs. Results. A total of 71 cases and 124 controls were included. IPA was documented in 11.3% of cases and in 7.3% of controls (P =.34). Among cases, ampicillin resistance was documented in 85% of antibiotic-exposed infants and in 63% of nonexposed infants (P =.19). Corresponding rates for first-generation cephalosporin resistance in urinary tract infection were 75% and 23.5% (P =.04). Conclusion. IPA is associated with a trend toward increased antibiotic resistance in late-onset SBIs. This should be taken into consideration in the selection of empirical therapy for febrile infants.