Genotyping of Methicillin Resistant Staphylococcus aureus Strains Isolated from Hospitalized Children.

Mouna Ben Nejma,Maha Mastouri,Abderrahmen Merghni

doi:10.1155/2014/314316

Abstract

Community associated methicillin resistant Staphylococcus aureus (CA-MRSA) is an emerging pathogen increasingly reported to cause skin and soft tissue infections for children. The emergence of highly virulencet CA-MRSA strains in the immunodeficiency of young children seemed to be the basic explanation of the increased incidence of CA-MRSA infections among this population. The subjects of this study were 8 patients hospitalized in the Pediatric Department at the University Hospital of Monastir. The patients were young children (aged from 12 days to 18 months) who were suffering from MRSA skin infections; two of them had the infections within 72 h of their admission. The isolates were classified as community isolates as they all carried the staphylococcal cassette chromosome mec (SCCmec) IV and pvl genes. Epidemiological techniques, pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing (MLST), were applied to investigate CA-MRSA strains. Analysis of molecular data revealed that MRSA strains were related according to PFGE patterns and they belonged to a single clone ST80. Antimicrobial susceptibility tests showed that all strains were resistant to kanamycin and 2 strains were resistant to erythromycin.

Highlights

Methicillin resistant Staphylococcus aureus (MRSA) was initially reported as a nosocomial pathogen responsible for adult infections [1]
In this study we investigate 8 MRSA strains isolated from patients hospitalized in the pediatric department
For all clinical isolates the detection of mecA gene and the identification of staphylococcal cassette chromosome mec (SCCmec) type were performed by amplification from genomic DNA, using multiplex polymerase chain reaction (PCR) method according to Oliveira and de Lencastre method [11]

Summary

Introduction

Methicillin resistant Staphylococcus aureus (MRSA) was initially reported as a nosocomial pathogen responsible for adult infections [1]. MRSA strains have emerged in the community causing community-acquired infections. CAMRSA has been recognized as a pathogen in adults and children without traditional risk factors for MRSA acquisition. Children colonized with MRSA are potential reservoirs for the spread of MRSA in the community [2, 3]. The infants and newborns with immunological immaturity, especially those born prematurely and those requiring specialized care, remained the major group susceptible to CAMRSA infections. Most CA-MRSA strains were associated with skin and soft tissue infections (SSTI) and necrotizing pneumonia [4]. The incidence of pediatric SSTI has increased rapidly in the previous decade [5,6,7]

Methods

Results

Conclusion