Burden of antibiotic resistance among children with typhoid in Gadap Town, Karachi, Pakistan

Abstract

Background: Increasing antibiotic resistance by pathogenic bacteria is observed in poor sanitary conditions. The peak incidence of typhoid occurs between 5-15 years of age. This is the most common bacteraemic illness of children in Pakistan. The aim of this study was to investigate the frequency of drug-resistant Salmonella Typhi and S. Paratyphi A in children hospitalized or treated as outpatients at a tertiary care centre that serves Gadap Town, an extensive slum district of Karachi. Methods: A total of 275 peripheral blood samples were collected from children up to 14 years old who presented with clinical features of typhoid to Fatima Hospital, Baqai Medical University, over a two-year period. Samples were cultured for growth of aerobic and facultative anaerobic bacteria, identified by biochemical reactions. Antimicrobial susceptibility was tested by Kirby-Bauer disc diffusion using eight different antibiotics. Results: Among all samples, 30 (10.9%) were positive for S. Typhi by blood culture. The rate of positivity was 23 (76.7%) cases for ages 5-14 years, three (10.0%) in each of age groups 2.0-2.9 and 4.0-4.9 years, and one patient (3.3%) aged 3.0-3.9 years. The majority of S. Typhi isolates were resistant to co-trimoxazole (66.7%), ampicillin (63.3%), nalidixic acid (60.0%), chloramphenicol (50.0%) and aztreonam (50.0%). However, most isolates were susceptible to ceftriaxone (76.7%) and ciprofloxacin (66.7%). There were 15 multidrug-resistant isolates but no typhoid-related deaths. Conclusion: Our findings show evidence of antimicrobial resistance by S. Typhi isolated from Karachiite children living in a poverty-stricken setting where water quality and sanitation are both unsatisfactory. Currently, Pakistan's most populated city is recognized as a focus of typhoid cases. Therefore, this first report of the emergence of confirmed cases of multidrug-resistant S. Typhi from the only public hospital in its largest neighbourhood identifies a grave public health concern.

Persistence of first-line antibiotic-resistant typhoid fever among Pakistani children: a growing concern for regional antimicrobial stewardship

“…Approximately 1,000 TF cases per 100,000 children have been reported annually over several years in Karachi, the country's most populous city and provincial capital of Sindh, located on the Arabian Sea coast (9). We have recently shown evidence of multidrug resistance in S. Typhi isolated from children living in a poverty-stricken slum district of Karachi where water quality and standards of sanitation are both unsatisfactory (7). This first report of the emergence of confirmed cases of MDR S. Typhi from the only public hospital in its largest neighborhood identifies a grave public health concern.…”

“…Multidrug-resistant (MDR) S. Typhi, defined as resistance to the three first-line antibiotics used to treat TF -ampicillin, chloramphenicol and cotrimoxazole, appeared in the 1970s and is now widespread globally. This is becoming extensively drug-resistant (XDR) S. Typhi (defined as MDR plus resistance to fluoroquinolones and third-generation cephalosporins), mainly through acquiring plasmids conferring antibiotic resistance via bacterial conjugation (commonly associated with the H-58 haplotype) (6,7). When an S. Typhi strain develops resistance by acquiring a promiscuous plasmid or undergoing genetic mutation consistent changes occur in the reported incidence of susceptibility to that antibiotic.…”

“…An elementary first step is the implementation of a regular and effective nationwide surveillance mechanism to enable clinical cases caused by MDR/XDR S. Typhi to be detected with reasonable accuracy. Moreover, a concerted and consolidated effort should be made to restrict ready access to non-prescribed antibiotics among the Persistence of first-line antibiotic-resistant typhoid fever among Pakistani children: a growing concern for regional antimicrobial stewardship general public in South Asian and South East Asian countries through unregulated 'over the counter' pharmacy sales and black market trade (6,7). Not only does this widespread availability provide a natural selection pressure for antimicrobial resistance by S. Typhi and other bacterial pathogens it is evident that a suboptimal dose of antibiotics can reduce the severity of TF symptoms sufficiently to obfuscate or delay a confirmatory diagnosis of infection.…”

Evaluation of antimicrobial susceptibility of Escherichia coli isolated from contaminated areas of Majengo slum in Meru County, Kenya

“…Improved sanitation facilities is one of the most important interventions needed in order to stop the spread of resistant bacteria. 3 A study on typhoid among young children, 4 stressed the need for careful monitoring of antimicrobial resistance in a view to prevent increase of resistance strains and resultant infections to vulnerable communities. Diarrheagenic E. coli has demonstrated a significant resistance to beta lactams antibiotics that are commonly prescribed, 5 with contributing factors to diarrhea cases attributed to poor quality of foods, poor water systems, lack of proper hygiene often due to lack of water and poor sanitation.…”

Designing of Multi-Epitope Peptide Vaccine Based on Outer Membrane Proteins OmpF, OmpC, and PgtE of Salmonella enterica Typhi

“…Antimicrobial resistance of pathogenic intestinal bacteria is one of the global health problems today. Multiresistance of S. Typhi to ampicillin, chloramphenicol, and cotrimoxazole has been reported (8)(9)(10).…”