Introduction
Extended-spectrum β-lactamases (ESBLs) are a heterogeneous group of
enzymes produced by certain bacteria that inactivate β-lactam
antibiotics via hydrolysis. They are most often found inEnterobacteriaceae , especially Escherichia coli andKlebsiella pneumoniae . Because of antimicrobial resistance,
diagnosing and treating ESBL-producing bacterial species are important
challenges.1,2
The prevalence of ESBL-producing Enterobacteriaceae (ESBL-E)
infection is not exactly known; however, the reported prevalence has
increased globally in recent years,3-5 while the
estimated prevalence in Asia is approximately 4.8% to
12.0%.2,6-8 Furthermore, the rates of ESBL-E
infection in maternity wards and outpatient clinics are also increasing.
Therefore, these issues related to ESBL-E infection are becoming more
crucial among obstetricians.9
Following the report of maternal ESBL-E vaginal colonization as a
precursor of mother-to-child transmission, the importance of vaginal
colonization was recently noted.10 According to a
recent systematic review, neonatal ESBL-E infection in neonatal
intensive care units is associated with significant morbidity and
mortality, with a mortality rate as high as 31%.11Meanwhile, the risk factors for ESBL-E infection in the general
population include prior antibiotic treatment, increased illness
severity, indwelling catheter use, and intensive care unit
admission.12,13 However, the specific risk factors for
ESBL-E vaginal colonization during pregnancy have not been studied, and
the potential clinical implications are still
unclear.14
With this background, we aimed to evaluate the changes in the rate of
ESBL-E vaginal colonization in high-risk pregnancies over the study
period and identify the risk factors for ESBL-E vaginal colonization
during pregnancy. Further, we analyzed the perinatal outcomes of
ESBL-E-positive patients.