Multidrug-Resistant and Extensively Drug-Resistant Salmonella Typhi and Salmonella Paratyphi: A Cross-Sectional Study at Provincial Headquarter Hospital, Gilgit

Abstract

Objective: To determine the antimicrobial susceptibility of Salmonella typhi and Salmonella paratyphi to recommended antibiotics and detect the frequency of multidrug-resistant (MDR) and extensively drug-resistant (XDR) Salmonella isolates.
Study Design: A cross-sectional study.
Place and Duration of Study: This study was conducted at the Microbiology Laboratory of Provincial Headquarter Hospital, Gilgit, Pakistan, from January 2024 to December 2025.
Methods: A total of 208 blood cultures with confirmed growth of Salmonella typhi and Salmonella paratyphi were included using non-probability convenience sampling. Blood cultures that grew non-lactose fermenters were further identified by colony morphology and the Analytical Profile Index (API 20E). The Kirby-Bauer disc diffusion method was used for antimicrobial sensitivity testing. The antibiotic zone diameters were reported as sensitive, intermediate, or resistant according to the Clinical and Laboratory Standards Institute (CLSI) 2023 guidelines.
Results: Most of the patients in our study were 1-10 years of age (45.7%), followed by 11-20 years (34.6%). The majority of the patients were males (63%). Out of 208 isolates of Salmonella, 168(80.8%) were identified as Salmonella typhi, and 40 (19.2%) were Salmonella paratyphi. The antimicrobial sensitivity pattern showed high resistance to ampicillin (92.8%), trimethoprim-sulfamethoxazole (81.7%), chloramphenicol (90%), cefixime (84.1%), ceftriaxone (80.2%), and ciprofloxacin (95.7%). Out of a total of 208 isolates, 134 (64.4%) of the isolates were MDR, and 84 (40.3%) were XDR. Six (2.9%) isolates were azithromycin-resistant, and 2 (1%) were meropenem-resistant.
Conclusion: Antimicrobial resistance to first-line and second-line antibiotics is very high in Salmonella typhi and Salmonella paratyphi. Salmonella Typhi exhibited significantly greater resistance to first- and second-line drugs than Salmonella Paratyphi. Around 64.4% of the isolates are multidrug-resistant, and 40.3% are extensively drug-resistant. Meropenem and azithromycin showed a good sensitivity pattern against these isolates.

How to cite this: Nasir S, Ali U, Aslam A, Salman H, Chaudhary MR, Mumtaz A. Multidrug-Resistant and Extensively Drug-Resistant Salmonella Typhi and Salmonella Paratyphi:  A Cross-Sectional Study at Provincial Headquarter Hospital, Gilgit. Life and Science. 2026; 7(3): 325-332. doi: http://doi.org/10.37185/LnS.1.1.1148