Molecular investigation of extended-spectrum β-lactamases (ESBLs) genes in the Salmonella isolates obtained from children with acute diarrhea

Abstract

Salmonellosis is an important public health concern among children in worldwide. Extended-spectrum β-lactams (ESBLs) cause resistance to clinically important beta-lactams which are generally used to treat invasive Salmonella infections. Therefore, the aim of this study was to investigate the presence of SHV , TEM and CTX-M genes in different strains of Salmonella isolated from children with acute diarrhea and to determine their resistance profile. In this cross-sectional study, 300 fecal samples were collected from children referred to the Amirkola Children's Hospital, Babol, Iran. Antibiotic susceptibility testing was done according to the CLSI guideline. ESBLs-producing strains were identified using double disk synergy test method on the Mueller-Hinton agar plates. Multiplex-PCR was performed using oligonucleotide specific primers to detect of SHV , TEM and CTX-M genes. In total, 7% (n; 21/300) salmonella were isolated, which 61.9%, 28.6% and 9.5% were Salmonella typhimurium , Salmonella enteritidis and Salmonella typhi , respectively. The prevalence of the ESBL-producing isolates were 52.4%. M-PCR results showed that 42.8%, 38.1% and 14.3% of isolates were carried CTX-M , TEM and SHV genes, respectively. Also, 18.2% of isolates harbored CTX-M , and TEM genes, simultaneously. The high rate of ESBLs-producing Salmonella strains in the pediatric patients is an alarm. It is also recommended that alternative drugs be used with less resistance, which requires further investigation.