Correlation between PFGE Groups andmrp/epf/slyGenotypes of HumanStreptococcus suisSerotype 2 in Northern Thailand

Prasit Tharavichitkul,Naoki Takenami,Kanreuthai Wongsawan,Shinji Takai,Volaluk Supajatura,Achara Fongcom,Banyong Khanthawa,Marcelo Gottschalk,Sumalee Pruksakorn

doi:10.1155/2014/350416

Abstract

Streptococcus suis infection is a severe zoonotic disease commonly found in Northern Thailand where people often consume raw pork and/or pig's blood. The most frequent clinical presentations are meningitis, sepsis, and endocarditis with higher rate of mortality and hearing loss sequelae. To clarify the correlation between pulsed-field gel electrophoresis (PFGE) groups and mrp/epf/sly genotypes of S. suis serotype 2, 62 patient and 4 healthy pig isolates from Northern Thailand were studied. By PFGE analysis, at 66% homology, most human isolates (69.4%) and 1 pig isolate were in group A, whereas 14.5% of human isolates and 3 out of 4 pig isolates were in group D. According to mrp/epf/sly genotypes, 80.6% of human isolates were identified in mrp + epf − sly − and only 12.9% were in mrp − epf − sly + genotypes; in contrast, 1 and 3 pig isolates were detected in these two genotypes, respectively. Interestingly, all isolates of S. suis serotype 2 classified in PFGE groups A, B, and E were set in mrp + epf − sly − genotypes. These data show a close correlation between PFGE groups and mrp/epf/sly genotypes of human S. suis serotype 2.

Highlights

Streptococcus suis, recognized as a significant swine and human pathogen, mainly causes meningitis, sepsis, endocarditis, and septic shock [1]
The present study aims to clarify the correlation between Pulsed-field gel electrophoresis (PFGE) and mrp/epf/sly genotypes of S. suis serotype 2 isolated from patients in Northern Thailand
Berthelot-Herault et al [8] confirmed the PFGE analysis to be a very useful tool for such investigations. They reported on the SmaI restriction PFGE patterns (A, B, and C) of 123 S. suis isolates from pigs in France and from humans worldwide

Summary

Introduction

Streptococcus suis, recognized as a significant swine and human pathogen, mainly causes meningitis, sepsis, endocarditis, and septic shock [1]. Virulence-related proteins, such as muramidase-released protein (MRP), extracellular factor (EF), and hemolysin (suilysin, SLY), are expressed by some strains of S. sui “as discussed by Gottschalk and Segura [1].”. These proteins are encoded by the genes mrp, epf, and sly, respectively. MRP/EF/SLY phenotypes or mrp/epf/sly genotypes of S. suis serotype 2 have been studied mostly in pig isolates with very little data for human isolates [1, 7], especially in Northern Thailand. The present study aims to clarify the correlation between PFGE and mrp/epf/sly genotypes of S. suis serotype 2 isolated from patients in Northern Thailand

Methods

Results

Conclusion