Multi-Locus Variable-Number Tandem Repeat Profiling of Salmonella enterica Serovar Typhi Isolates from Blood Cultures and Gallbladder Specimens from Makassar, South-Sulawesi, Indonesia

Abstract

Multi-locus variable-number tandem repeat analysis differentiated 297 Salmonella enterica serovar Typhi blood culture isolates from Makassar in 76 genotypes and a single unique S. Typhi genotype was isolated from the cholecystectomy specimens of four patients with cholelithiasis. The high diversity in S. Typhi genotypes circulating in Makassar indicates that the number of carriers could be very large, which may complicate disease prevention and control.

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

“…The predominant alleles of TR1 loci revealed a repeat number of 5 among the study isolates, which was also shown in earlier studies among S. Typhi Indian isolates (31,33). The range of number of repeats and prevalent alleles in VNTR loci was found to vary in S. Typhi isolates from different geographical locations (10,23,28). None of the 6 VNTR loci was found to contain zero-repeat copy in any of the study strains (Table 2).…”

“…Compared to PFGE, MLVA has been adopted by several European countries for epidemiological investigations of nontyphoidal S. enterica serovars, including Typhimurium and Enteritidis, due to its cost-effectiveness, rapid turnaround time, and ease of inter-laboratory comparison of results (30). Nevertheless, for S. Typhi, the MLVA typing method is still under evaluation (10,28,23). The present study examined the discriminatory ability of MLVA typing with respect to PFGE and antimicrobial resistance profiles of S. Typhi (n = 66) circulating in India during 2007-14.…”

“…DNA sequences were analyzed with Sequence Scanner software version 1.0 (Applied Biosystems) followed by identification of repeat number of VNTR loci accessible at a public database (http: minisatellites.u-psud.fr). The cluster analysis was performed using the UPGMA algorithm, and a rooted tree was constructed, which is available at http: minisatellites.u-psud.fr (28). The isolates showing distinct MLVA patterns were defined as MLVA types that differed by minimum number of changes in the number of repeats of any locus.…”

Salmonella chronic carriage: epidemiology, diagnosis, and gallbladder persistence

“…Laboratory studies have shown that Salmonella respond rapidly in vitro to growth in gallbladder mimicking conditions, increasing biofilm formation and antimicrobial resistance in the presence of bile [19], and altering expression of fimbrial and outer membrane proteins in response to growth in bile and on cholesterol substrates [21, 22]. Recent clinical evidence supports the notion of ongoing bacterial adaptation to the gallbladder environment; with clinical isolates from gallbladder carriers exhibiting a common genetic profile distinct from those of isolates infecting other sites of the body [23], potentially implying a specific S . Typhi genotype associated with preferential infection of gallbladder.…”

Relationships between Flagellin Genes Variants of <i>Salmonella</i> <i>enterica</i> Serovar Typhi and Severity of Illness from Acute and Carriers State of Typhoid Fever

“…The clinical symptoms as severity of illness like stupor, melena and perforation in carrier state of typhoid fever has related with flagellin genes variants especially Hd Several studies suggested that flagellin genes variants of Hj + association of decreased severity of illness, motility and invasiveness of bacteria and compared with flagellin genes variants of Hd + [10] and flagellin genes variants of z66Ind + might seems related with severity of illness of typhoid fever [19]. It is supported by our results that flagellin genes variants of Hd + z66Ind…”