Trend of Antimicrobial Resistance Among Salmonella Typhi Isolated from Pediatric Population Presenting at a Tertiary Care Hospital in Lahore

Abstract

Background and Objective: Typhoid fever caused by Salmonella typhi (S. typhi) is an important cause of morbidity and mortality worldwide. The emergence of resistance against the first and second line of drugs has limited the range of drug choices for its treatment. Therefore, the present study was designed to assess the status of drug resistance in S. typhi isolated from the blood samples of pediatric patients reporting at a leading tertiary care hospital in Lahore.

Methods: This descriptive study was conducted at the Pathology Department of Allama Iqbal Medical College, Lahore, Pakistan, over a period of 2 years. A total of 1,306 blood samples were aseptically collected from the pediatric population of Jinnah Hospital, Lahore, Pakistan, after obtaining informed assent from the parents/guardians. The samples were transferred into a Bact/Alert blood culture bottle. After the detection of microbial growth by the Bact/Alert 3-D system, bacterial isolates were identified by standard microbiological procedures. VITEK 2 compact automated identification and antimicrobial susceptibility testing instrument (bioMerieux) was used for the antimicrobial sensitivity testing. Data were entered and analyzed by using Statistical Package for the Social Sciences version 21.0.

Results: A total of 235 out of 1,306 (17.9%) blood culture samples yielded bacterial growth, among which 62.5% (n = 147) were S. typhi. Among 147 S. typhi isolates, 70.6% were multidrug resistant, while 63% were extensively drug resistant (XDR). Maximum resistance against first-line drugs observed was for ampicillin (79.4) and co-trimoxazole (67.2).

Conclusion: The emergence and spread of XDR S. typhi with a high level of resistance are quite alarming, leaving limited treatment options for the pediatric population. Moreover, increasing resistance to antibiotics demonstrates the quick waning of the efficacy of available first and second-line drugs in the treatment of typhoid fever.