Molecular typing and occurrence of beta-lactam resistance genes of Shigella sonnei strains isolated from 1983 to 2014 in the São Paulo state of Brazil.

Autor: Seribelli, Amanda Ap., Frazão, Miliane R., Medeiros, Marta I. Cazentini, Stehling, Eliana G., Falcão, Juliana P.
Předmět:
Zdroj: Microbiology & Immunology; Dec2017, Vol. 61 Issue 12, p547-553, 7p
Abstrakt: ABSTRACT Shigella sonnei, which has generally been associated with dysentery in developed countries, has recently been emerging in developing countries. Specifically, in Brazil few published studies have that molecularly characterized this species. The aims of this study were to analyze the efficacy of typing using multiple-locus variable-number tandem-repeat analysis (MLVA), study the phylogeny by multi-locus sequence typing (MLST) and assess the presence of some beta-lactam resistance genes in S. sonnei strains isolated from human diarrhoeic faeces in the São Paulo State in Brazil between 1983 and 2014. Seventy-two such S. sonnei strains were typed by MLVA and grouped into two clusters. The discrimination index of MLVA was found to be 0.996. Twenty strains were typed by MLST as ST152. In addition, the blaTEM gene was detected in eight (72.7%) of the 11 S. sonnei strains that had previously been shown to be resistant to β-lactams. However, blaCTX-M-1group, blaCTX-M-9group and blaSHV genes were not found. MLVA results suggested the existence of two prevalent subtypes in the S. sonnei strains studied, confirming previous results. Moreover, MLVA efficiently discriminated monomorphic S. sonnei species. Because the S. sonnei strains studied belonged to clonal complex 152 and all isolates were typed as ST152, MLST is not a suitable method for studying the population structure of S. sonnei. Although, the rates of β-lactam resistance were not high in the present study, the frequency of blaTEM may represent a risk for patients receiving antimicrobial treatment. Taken together, the results provide better molecular characterization of this globally clinically important pathogen. [ABSTRACT FROM AUTHOR]
Databáze: Complementary Index