Molecular characterization of multidrug-resistant Shigella species isolated from epidemic and endemic cases of shigellosis in India.
Shigella species represent one of the growing numbers of antimicrobial-resistant bacteria in developing countries. Fluoroquinolone-resistant strains of Shigella dysenteriae type 1 and Shigella flexneri type 2a emerged in India during 2002 and 2003, respectively. Sixty strains of Shigella from different parts of India were analysed for antimicrobial susceptibility, the presence of the qnr plasmid, mutations in the quinolone resistance determining regions (QRDRs), fluoroquinolone accumulation, and the presence of other genes encoding resistance to various antimicrobials. Fluoroquinolone-resistant strains had mutations in gyrA and parC genes and had an active efflux system. They were also resistant to several other antimicrobials but were susceptible to azithromycin and ceftriaxone. The majority of the strains harboured genes encoding resistance to ampicillin (97 %), tetracycline (95 %), streptomycin (95 %) and chloramphenicol (94 %). PFGE analysis revealed clonality among strains of S. dysenteriae types 1 and 5, S. flexneri type 2a and Shigella boydii type 12.
National Institute of Cholera and Enteric Diseases, Kolkata, India.
Gururaja Perumal
GP
Pazhani
National Institute of Cholera and Enteric Diseases, Kolkata, India.
Swapan Kumar
SK
Niyogi
Department of Chemistry, Bose Institute, Kolkata, India.
Anil Kumar
AK
Singh
National Institute of Cholera and Enteric Diseases, Kolkata, India.
Bhaswati
B
Sen
Department of Microbiology, Post Graduate Institute of Basic Medical Sciences, Chandigarh, India.
Neelam
N
Taneja
Department of Chemistry, Bose Institute, Kolkata, India.
Manikuntala
M
Kundu
Osaka Prefecture University, Osaka, Japan.
Shinji
S
Yamasaki
National Institute of Cholera and Enteric Diseases, Kolkata, India.
Thandavarayan
T
Ramamurthy
D000900:Anti-Bacterial Agents / Q000494:pharmacology; D001426:Bacterial Proteins / Q000235:genetics; D003967:Diarrhea / Q000453:epidemiology / Q000382:microbiology; D004196:Disease Outbreaks; D024901:Drug Resistance, Multiple, Bacterial / Q000235:genetics; D004405:Dysentery, Bacillary / Q000453:epidemiology* / Q000382:microbiology; D016521:Electrophoresis, Gel, Pulsed-Field; D019353:Endemic Diseases; D024841:Fluoroquinolones / Q000494:pharmacology; D006801:Humans; D007194:India / Q000453:epidemiology; D008826:Microbial Sensitivity Tests; D008969:Molecular Sequence Data; D010957:Plasmids; D017422:Sequence Analysis, DNA; D012760:Shigella / Q000145:classification* / Q000187:drug effects / Q000235:genetics* / Q000302:isolation & purification; D012763:Shigella flexneri / Q000145:classification / Q000187:drug effects / Q000235:genetics / Q000302:isolation & purification
D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D024841:Fluoroquinolones