Frequency and Antimicrobial Resistance Profile of Salmonella Typhi Isolated From District Buner

Abstract

Objective: The objective of this study was to investigate the frequency and drug resistance of Salmonella typhi in district Buner, Khyber Pakhtunkhwa. Methodology: This cross-section study was conducted at District Head Quarter Hospital Buner and private diagnostic centers from Jan 2020 to May 2021. A total of 460 blood samples were collected from OPD patients reported with signs and symptoms of Typhoid fever. Samples were cultured on blood and MacConkey agar and incubated at 37? for 24 hours. Bacterial identification was done on colony morphology, gram staining, and polyvalent antisera for strain identification. Finally, antibiotic susceptibility testing was done for the isolated bacteria. All commonly prescribed first-line and second-option antibiotics were tested on Mueller Hinton agar by Kirby Bauer disk diffusion method following CLSI guidelines 2020. Result: A total of 240 out of 460 samples showed bacterial growth where Salmonella typhi was found in 98 (40.8%) cases. Among them, 28(28.6%) were reported as MDR while 1 (17.4%) were XDR. Out of the XDR, 4 strains were found resistant to Vancomycin and clarithromycin as well. The isolated S. typhi was 100% sensitive to Meropenem, and Azithromycin, however showed 100% resistance to Aztreonam, Ampicillin, and Cotrimoxazole. Prevalence of S. typhi was more (50%) in females while resistance was reported more in age group 20-40 years. Conclusion: The frequency of Salmonella typhi at district Buner was 41% in patients reported with high-grade fever where 28% of the strains reported were multidrug resistant. Some extended spectrum drug-resistant S. typhi and Vancomycin and Clarithromycin resistant strains were also reported which is alarming. Meropenem, and Azithromycin were the only drugs effective against most of the strains. However, resistance to these drugs may develop soon if we do not stop the empirical excessive use of antibiotics. Keywords: Multidrug-resistant, Salmonella typhi, Typhoid fever, Extended spectrum drug-resistant