Deciphering effect of maternal postpartum antibiotic prophylaxis on infant gut microbiome: a whole metagenomic analysis

Aim: To analyze the impact of postpartum antibiotic (Ab) prophylaxis on the infant gut microbiome. Materials & methods: Whole metagenomic analysis was performed on breast milk and infant fecal samples collected from mother-infant pairs who belonged to two groups: an Ab group comprising mothers who had received a single course of Abs in the immediate postpartum period and a non-Ab group comprising mothers who had not received Abs. Results: The characteristic presence of Citrobacter werkmanii, an emerging multidrug-resistant uropathogen, and a higher relative abundance of genes encoding resistance to specific Abs were noted in samples from the Ab group compared with those from the non-Ab group. Conclusion: Policies regarding prophylactic Ab prescription across government and private health sectors in the postpartum period need to be strengthened.

Critical insights into antibiotic resistance transferability in probiotic Lactobacillus

Probiotics are live microorganisms that, when administered in adequate amounts, confer a health benefit on the host, with respect to metabolism, immune function, and nutrition. Any perturbation of these beneficial microbes leads to gut dysbiosis, which triggers the development of various disorders in the gastrointestinal system. Probiotics play a key role in resolving the dysbiosis posed by external factors such as antibiotics, other substances, or interventions. Supplementing probiotics with antibiotics is favorable in reducing the harmful effects of antibiotics on gut flora. These microbes also possess specific intrinsic drug resistance mechanisms that aid their survival in the internal environment. According to US Food and Drug Administration reports, species belonging to Lactobacillus and Bifidobacterium genera are the most common probiotics consumed by humans through commercial products. However, various studies have reported the tendency of microbes to acquire specific drug resistance, in recent years, through various mechanisms. The reports on transferable resistance among probiotics are of major concern, of which minimal information is available to date. The aim of this review was to describe the pros and cons of drug resistance among these beneficial microorganisms with emphasis on the recommended selection criteria for specific probiotics, devoid of transferable drug resistance genes, suitable for human consumption.