Effects and changes of intrapartum antimicrobial prophylaxis on antibiotic resistance genes in gut microbiota of infants within 6 months of age / 中国儿童保健杂志

ABSTRACT

【Objective】 To explore the impact of intrapartum antibiotic prophylaxis (IAP) on antibiotic resistance genes (ARGs) in the gut microbiota of infants up to 6 months of age and their longitudinal changes, in order to provide theoretical basis for the rational use of antibiotics and antibiotic resistance control. 【Methods】 Fecal samples were collected within 3 days, 2 months, and 6 months from a maternal and birth cohort conducted between January 2018 and June 2019. A panel of 6 common ARGs (aac(6′)-Ib, qnrS, blaTEM, ermB, mecA, tetM) were tested, the absolute abundance and positive detection rate by qPCR were calculated. Nonparametric and linear mixed model (LMM) analysis were used to assess the influence of IAP on the absolute abundance of antibiotic resistance genes and the longitudinal changes in their abundance at the three time points. 【Results】 A total of 157 samples from 65 singleton infants were analyzed, including 15 mothers (23.1%) who received IAP. The detection rate of ARGs was high in infants up to six months of age, and the abundance of ARGs tended to increase over time. IAP significantly increased the abundance of the mecA gene in the gut microbiota of vaginally delivered infants at 6 months of age (6.1±1.1 in the VDIAP group vs. 3.8±4.6 in the VDno-IAP group, P=0.046). Additionally, in cesarean section infants, there was a significant increase in the abundance of aac(6′)-Ib genes at 2 months (β=3.81, ,P<0.05), P<0.05] and 6 months of age (β=4.89, ,P<0.001), P<0.001) compared to 3 days of age. 【Conclusions】 The findings suggest that IAP can increase the abundance of ARGs in 6-month-old infants, and this effect is still significant after stratifying by delivery mode. Therefore, the rational and standardized use of intrapartum antibiotics may help reduce the development of antibiotic resistance.