Molecular profiling of antimicrobial resistance and integron association of multidrug-resistant clinical isolates of  Shigella  species from Faisalabad, Pakistan.
Bacillary dysentery, common in developing countries, is usually caused by  Shigella  species. A major problem in shigellosis is the rapid emergence of multidrug-resistant strains. This is the first detailed molecular study on drug resistance of Shigella isolates from the Faisalabad region of Pakistan. Ninety-five Shigella isolates obtained after screening of 2500 stool samples were evaluated for in vitro resistance to commonly used antimicrobial agents; the presence or absence of 20 of the most relevant drug resistance genes; and the prevalence of integrons 1, 2, and 3.  Shigella flexneri  was found to be the most prevalent and most resistant species. Collectively, high resistance was found towards ampicillin (96.84%), tetracycline (93.68%), streptomycin (77.89%), and chloramphenicol (72.63%). Significant emerging resistance was detected towards the modern frontline drugs ciprofloxacin (12.63%), cefradine (17.89%), ceftriaxone (20.00%), cefoperazone (22.10%), and cefixime (28.42%). Prevalence rates for bla(TEM), bla(CTX-M), gyrA, gyrB, qnrS, aadA1, strAB, tetA, tetB, catA, and catP were 78.94%, 12.63%, 20.00%, 21.05%, 21.05%, 67.36%, 42.10%, 12.63%, 53.68%, 33.68%, and 25.26%, respectively. Class 2 integrons (42.10%) were more common in the local isolates. Simultaneous detection of class 1 and 2 integrons in some isolates and a rapidly emerging resistance to modern frontline drugs are the major findings of this study.
Health Biotechnology Division, National Institute for Biotechnology and Genetic Engineering, Faisalabad, Pakistan.
Aaysha
A
Tariq
Abdul
A
Haque
Aamir
A
Ali
Saira
S
Bashir
Muhammad Asif
MA
Habeeb
Muhammad
M
Salman
Yasra
Y
Sarwar
D000890:Anti-Infective Agents / Q000494:pharmacology*; D024881:Drug Resistance, Bacterial / Q000235:genetics; D004405:Dysentery, Bacillary / Q000382:microbiology; D006801:Humans; D032023:Integrons / Q000235:genetics*; D008826:Microbial Sensitivity Tests; D010154:Pakistan; D012760:Shigella / Q000187:drug effects* / Q000235:genetics*; D012763:Shigella flexneri / Q000235:genetics
D000890:Anti-Infective Agents