Related Experiment Video
Updated: Jul 6, 2025

Detection of Horizontal Gene Transfer Mediated by Natural Conjugative Plasmids in E. coli
Published on: March 24, 2023
Detection of Salmonella typhi Isolates and Ceftriaxone Strains Harbouring CTX-M-15 Gene
Rida Sohail1, Yasmeen Taj1, Luqman Satti2
1Department of Pathology, Bahria University of Health Sciences, Karachi, Pakistan.
Objective:
To determine blaCTX-M-15(Cefotaxime-Munich) gene amongst the extensively drug resistant (XDR) Salmonella typhi (S. typhi) isolates by quantitative Polymerase Chain Reaction (qPCR).
Study Design:
Observational, cross-sectional study. Place and Duration of the Study: PNS Shifa Hospital and Bahria University of Health Sciences (BUHS), from January to June 2022.
Methodology:
All the patients clinically suspected of enteric fever, whose blood culture specimens yielded growth of S. typhi were included in this study. These samples were confirmed by serotyping and biochemical reactions. The ceftriaxone resistance was evaluated by antibiotic susceptibility test according to CLSI 2020 guidelines, whereas blaCTX-M-15 gene was detected by (PCR) using gene-specific primers.
Results:
Out of 149 S. typhi isolates, 87.2% were confirmed XDR S. typhi resistant to ceftriaxone (CRO). Among these, 83.9% harboured blaCTX-M-15 gene.
Conclusion:
There was a very high frequency of XDR S. typhi harbouring blaCTX-M-15 in Karachi, Pakistan.
Key Words:
blaCTX-M-15, Salmonella typhi, Third generation cephalosporin, Typhoid fever, Extensively drug resistant.
More Related Videos
08:58Isolation and Identification of Waterborne Antibiotic-Resistant Bacteria and Molecular Characterization of their Antibiotic Resistance Genes
Published on: March 3, 2023
08:00Enrichment and Detection of Clostridium perfringens Toxinotypes in Retail Food Samples
Published on: October 18, 2019