Prevalence and Risk Factors for Nasal and Oropharyngeal Carriage of Staphylococcus Aureus in Insulin-Dependent Diabetics Individuals

Abstract

Individuals with insulin-dependent diabetes are a risk group for infections caused by Staphylococcus aureus. The objective of this study was to determine the prevalence and risk factors for nasal and oropharyngeal carriage of S. aureus and MRSA in insulin-dependent diabetic individuals from Botucatu, São Paulo, Brazil. Additionally, susceptibility profiling, detection of the mecA gene, SCCmec typing and molecular typing by PFGE and MLST were performed in nasal and oropharyngeal swabs of 312 subjects. The prevalence of S. aureus and MRSA was 30.4% and 4.8%, respectively. SCCmec type IV was the predominant type among isolates, although some carried SCCmec types I and II. MRSA and MSSA clones were detected among the isolates of this population. In addition, an important clonal lineage (ST398) was identified among resistant and susceptible isolates. Age and lung disease were negatively associated with S. aureus carriage, while lower-extremity ulcers were a risk factor for S. aureus carriage. For MRSA, only male gender was a risk factor. These data suggest widespread dissemination of MRSA in the insulin-dependent diabetic population studied, as well as the emergence of important lineages among these individuals.