Changing paradigm of antibiotic resistance amongst Escherichia coli isolates in Indian pediatric population

Antimicrobial resistance happens when microorganisms mutates in manners that render the drugs like antibacterial, antiviral, antiparasitic and antifungal, ineffective. The normal mutation process is encouraged by the improper use of antibiotics. Mutations leading to quinolone resistance occur in a highly conserved region of the quinolone resistance-determining region (QRDR) of DNA gyrAse and topoisomerase IV gene. We analyzed antibiotic resistant genes and single nucleotide polymorphism (SNP) in gyrA and parC genes in QRDR in 120 E. coli isolates (both diarrheagenic and non-pathogenic) recovered from fresh stool samples collected from children aged less than 5 years from Delhi, India. Antibiotic susceptibility testing was performed according to standard clinical and laboratory standards institute (CLSI) guidelines. Phylogenetic analysis showed the clonal diversity and phylogenetic relationships among the E. coli isolates. The SNP analysis depicted mutations in gyrA and parC genes in QRDR. The sul1 gene, responsible for sulfonamide resistance, was present in almost half (47.5%) of the isolates across the diseased and healthy samples. The presence of antibiotic resistance genes in E. coli isolates from healthy children indicate the development, dissemination and carriage of antibiotic resistance in their gut. Our observations suggest the implementation of active surveillance and stewardship programs to promote appropriate antibiotic use and minimizing further danger.