Antimicrobial Susceptibility Patterns of Salmonella enterica Serovar Typhi Among Febrile Patients at a Tertiary Care Hospital in Peshawar, Pakistan

Background: Typhoid fever, caused by Salmonella enterica serovar Typhi, remains a major public health challenge worldwide, particularly in low- and middle-income countries such as Pakistan. The indiscriminate use of antibiotics has contributed to the emergence of multidrug-resistant (MDR) and extensively drug-resistant (XDR) strains, significantly limiting effective treatment options and increasing the burden on healthcare systems. Objective: To determine the hospital-based prevalence and antimicrobial susceptibility pattern of Salmonella enterica serovar Typhi among febrile patients at Northwest Teaching Hospital, Peshawar, with particular emphasis on resistance to third-generation cephalosporins, fluoroquinolones, and commonly prescribed antibiotics. Methodology: This descriptive cross-sectional study was conducted from September 2021 to September 2023 and included 127 febrile patients presenting with suspected enteric fever. Blood cultures were performed for pathogen identification, followed by antimicrobial susceptibility testing using the modified Kirby–Bauer disc diffusion method in accordance with Clinical and Laboratory Standards Institute (CLSI) guidelines. Data were analyzed using SPSS version 25. Results: Out of 127 enrolled patients, 122 were included in the final analysis. Salmonella enterica serovar Typhi was isolated in 102 (83.6%) cases. The highest resistance rates were observed for co-trimoxazole 96 (94.1%), chloramphenicol 94 (92.1%), and ampicillin 92 (90.1%). In contrast, all isolates showed complete sensitivity to meropenem 102 (100%), while azithromycin demonstrated a sensitivity of 80 (78.4%). Conclusion: The study demonstrates a high prevalence of Salmonella enterica serovar Typhi and a concerning level of antimicrobial resistance among febrile patients in Peshawar. While resistance to first-line and commonly used antibiotics is widespread, meropenem and azithromycin remain effective therapeutic options. These findings underscore the urgent need for continuous antimicrobial surveillance, rational antibiotic use, and strengthened public health interventions to curb the spread of resistant typhoid fever. Keywords: Antimicrobial Resistance, Antibiotic Susceptibility, Peshawar, Salmonella Typhi, Typhoid Fever.