Blood-Culture Isolation and Antimicrobial Resistance Patterns of Salmonella Typhi among Patients with Suspected Typhoid Fever in Peshawar, Pakistan: Original Article

Jamila Hiader; Sofia Bano; Bibi Maryam; Maham Iqbal; Muhammad Usman; Aiman Waheed

doi:10.69837/pjammr.v4i2.119

Authors

Jamila Hiader Assistant Professor (Microbiology), Institute of Pathology and Diagnostic Medicine, Khyber Medical University (KMU), Peshawar, Pakistan https://orcid.org/0009-0009-6469-1377
Sofia Bano Undergraduate students (BS Microbiology), Institute of Pathology and Diagnostic Medicine, Khyber Medical University (KMU), Peshawar, Pakistan https://orcid.org/0000-0002-3894-4758
Bibi Maryam Undergraduate students (BS Microbiology), Institute of Pathology and Diagnostic Medicine, Khyber Medical University (KMU), Peshawar, Pakistan https://orcid.org/0009-0006-1513-226X
Maham Iqbal Undergraduate students (BS Microbiology), Institute of Pathology and Diagnostic Medicine, Khyber Medical University (KMU), Peshawar, Pakistan
Muhammad Usman Undergraduate students (BS Microbiology), Institute of Pathology and Diagnostic Medicine, Khyber Medical University (KMU), Peshawar, Pakistan
Aiman Waheed Research Associate, Institute of Pathology and Diagnostic Medicine, Khyber Medical University (KMU), Peshawar, Pakistan https://orcid.org/0009-0009-6469-1377

DOI:

https://doi.org/10.69837/pjammr.v4i2.119

Keywords:

Salmonella Typhi; Typhoid fever; Bloodstream infection; Antimicrobial resistance; Antimicrobial susceptibility; Blood culture

Abstract

Background: Typhoid fever remains an important public health challenge in South Asia, where increasing antimicrobial resistance in Salmonella enterica serovar Typhi (S. Typhi) complicates empirical treatment and disease control. Local laboratory-based surveillance is essential for characterizing circulating resistance patterns and informing antimicrobial selection.

Objective: To determine the frequency of blood-culture isolation of S. Typhi among patients clinically suspected of typhoid fever and to characterize the antimicrobial susceptibility patterns of recovered isolates in Peshawar, Pakistan.

Methodology: A laboratory-based cross-sectional study was conducted at the Khyber Medical University–Public Health Reference Laboratory, Peshawar, from October to December 2025. Seventy blood specimens obtained from clinically suspected typhoid patients were processed using standard blood-culture, microbiological, and biochemical procedures. Confirmed S. Typhi isolates were subjected to antimicrobial susceptibility testing using the Kirby–Bauer disk diffusion method in accordance with Clinical and Laboratory Standards Institute recommendations. Descriptive statistics were used to summarize participant characteristics, bacterial isolation, and antimicrobial susceptibility profiles.

Results: S. Typhi was isolated from 48 of 70 blood specimens (68.6%), making it the predominant organism recovered. Participants aged 1–10 years constituted the largest age group (54.3%), while males represented 54.3% of the study population. Among S. Typhi isolates, the highest resistance was observed to ampicillin (87.5%), cefotaxime (81.3%), trimethoprim–sulfamethoxazole (81.3%), chloramphenicol (62.5%), and ciprofloxacin (52.1%). Conversely, high in vitro susceptibility was observed for tetracycline (97.9%), meropenem (95.8%), and azithromycin (87.5%).

Conclusion: The findings demonstrate substantial antimicrobial resistance among blood-culture-confirmed S. Typhi isolates in Peshawar, particularly to several historically important therapeutic agents. Continued laboratory-based AMR surveillance, antimicrobial stewardship, microbiological confirmation, and integrated typhoid prevention strategies are warranted.