Molecular Subtyping of Salmonella enterica Serovar Typhi by Pulsed-Field Gel Electrophoresis and Multiple-Locus Variable-Number Tandem-Repeat Analysis in India: Their Association with Antimicrobial Resistance Profiles

Japanese journal of infectious diseases

Rajni Gaind²  Raghavendra Kulkarni³  Shanta Dutta³  Indranil Roy⁵  Sriparna Samajpati⁶  Surojit Das⁶  Dilip Kumar Paul⁸  Monorama Deb⁸  Sathish Sankar⁹ 

[1] Hospitals;Research Centre;Safdarjung Hospital;Clinical Division, Dr. B. C. Roy Post Graduate Institute of Pediatric Sciences;Microbiology Division, Calcutta Medical Research Institute;Microbiology Division, National Institute of Cholera and Enteric Diseases;Microbiology Division, SDM College of Medical Sciences &Microbiology Division, Vardhaman Mahavir Medical College &Sri Sakthi Amma Institute of Biomedical Research, Sri Narayani Hospital &

关键词: S.Typhi;    antimicrobial resistance;    molecular subtyping;    PFGE;    MLVA;   

DOI  :  10.7883/yoken.JJID.2016.478

学科分类：传染病学

来源: National Institute of Infectious Diseases

【 摘 要 】

Molecular subtyping and DNA sequencing-based methods, which are commonly used for discriminating Salmonella enterica serovar Typhi (S. Typhi) isolates, lead to improved molecular epidemiological investigations for prevention and control of typhoid fever. We obtained S. Typhi blood isolates (n = 66) from India during 2007–14 for molecular subtyping by pulsed-field gel electrophoresis (PFGE) and multiple-locus variable-number tandem-repeat (VNTR) analysis (MLVA) in association with antibiotic resistance profiles. Genotypic diversity was observed more by MLVA (Simpson’s index of diversity, D value = 0.997) than PFGE (D value = 0.864). Two prevalent pulsotypes containing nalidixic acid-resistant (NALR) and NALR-ciprofloxacin-resistant (CIPR) S. Typhi isolates circulated in India. Multidrug-resistant (MDR), NALR-CIPR, and most NALR isolates were found to be clonal by PFGE. MLVA could differentiate the clonal isolates. Most of the MDR and NALR-CIPR isolates showed variation in single or double VNTR loci, whereas NALR isolates varied in more than 2 loci, reflecting higher genetic diversity among the NALR isolates. Of the 6 VNTR loci, TR4,699 (D value = 0.838) and Sal02 (D value = 0.890) loci played important roles as MLVA cluster-supporting alleles. The rapid turnaround time and high-level discriminatory power of MLVA may be useful for tracking and controlling the transmission of S. Typhi isolates during epidemiological investigations.

【 授权许可】

Unknown