Screening of mecI Gene in Staphylococcus Strains Isolated in Transylvania Region of Romania

In the last few decades, methicillin-resistant Staphylococcus aureus (MRSA) strains have become a serious health care problem. However, in the European Union/European Economic Area countries the prevalence of the invasive MRSA isolates has decreased in recent years; in Romania, the considerably high prevalence of these strains is still unchanged. In this study, 396 staphylococcal strains were screened using molecular biology techniques for the presence of the nucA, mecA, and mecI genes and for the detection of the possible mutations accumulated in the mecI gene. More than half of the collected Staphylococcus strains (59.34%) were determined as S. aureus, and 63 strains were considered as MRSA. Small number of MRSA strains (n = 6; 54.54% of invasive S. aureus) originated from hemoculture. The mecI gene was present in 22 MRSA strains and in 4 methicillin-resistant coagulase-negative staphylococci strains. The majority of the mecI-positive MRSA strains contained the C to T substitution at position 202; furthermore, one previously undescribed mutation (C to G transversion at nucleotide position 285) was detected in one MRSA strain.