Phenotypic and Genotypic Detection of Resistance Genes in Salmonella enterica serovar Typhimurium Associated with Gastroenteritis

HistoryThe global rise of antimicrobial resistance (AMR) poses a significant challenge for both human and veterinary health, particularly in low and middle-income countries where surveillance and stewardship remain limited.This study assessed the prevalence and resistance profiles of bacterial pathogens in clinical cases, with an emphasis on Salmonella enterica serovar Typhimurium.Out of 102 clinical samples, 54 (52.9%) were confirmed positive for S. Typhimurium.Phenotypic susceptibility testing revealed a high frequency of multidrug resistance, with marked resistance to fluoroquinolones, third-generation cephalosporins, and aminoglycosides.Molecular screening further detected resistance determinants, including qnrS (72%) and CTX-M (60%), with 40% of isolates harboring both genes, suggesting horizontal transfer and dissemination of extended-spectrum β-lactamases (ESBLs).These findings indicate the emergence of highly resistant Salmonella strains that may compromise therapeutic efficacy, increase the risk of treatment failure, and enhance zoonotic transmission.The results underscore the urgent need for integrated surveillance programs, prudent antibiotic use in clinical and veterinary practice, and alternative therapeutic approaches to mitigate the growing AMR threat at the human-animal interface.