Enterotoxin A Producing Methicillin Resistant Staphylococcus aureus in Profiteroles

Staphylococcal enterotoxins are members of a family of more than 20 different staphylococcal and streptococcal exotoxins that are functionally related and share sequence homology. These bacterial proteins are known to be pyrogenic and are connected to significant human diseases that include food poisoning. The aim of this study was to detect the enterotoxin A producing Staphylococcus aureus strains in profiteroles obtained from 2 confectionaries in Isfahan. Sampling was carried out 4 times from 2 confectionaries in Isfahan from profiteroles. Serial dilutions from each sample were prepared and samples were filtered. Filters were put on Baird parker agar without oxacillin and supplemented with oxacillin. After 48 h incubation at 37ºC and black colonies were selected. Isolates were identified at the species level using biochemical tests and specific primers. Susceptibility of isolates selected from medium supplemented with antibiotic to oxacillin was determined using disc diffusion and broth micro dilution assays. Presence of mecA and sea genes was checked using PCR. Totally, 679 and 18 S. aureus and methicillin resistant S. aureus strains were isolated from different media, respectively. All 18 isolated showed resistance to oxacillin and resistance in 78% of MRSA isolates was very high (MIC≥256 μg/ml). sea gene was detected in 4 and 100% of S. aureus and MRSA isolates, respectively. One hundred percent of the MRSA isolates contained mecA gene. High prevalence of enterotoxin A producing MRSA isolates in different foods and specially profiteroles, which is an enrichment medium for growth and proliferation of bacteria is a warning for public health.