The Frequency of Methicillin-Resistant Staphylococcus aureus and Coagulase Gene Polymorphism in Egypt

The current study aimed to use Coagulase gene polymorphism to identify methicillin-resistant Staphylococcus aureus (MRSA) subtypes isolated from nasal carriers in Minia governorate, Egypt, evaluate the efficiency of these methods in discriminating variable strains, and compare these subtypes with antibiotypes. A total of 400 specimens were collected from nasal carriers in Minia governorate, Egypt, between March 2012 and April 2013. Fifty-eight strains (14.5%) were isolated and identified by standard microbiological methods as MRSA. The identified isolates were tested by Coagulase gene RFLP typing. Out of 58 MRSA isolates 15 coa types were classified, and the amplification products showed multiple bands (1, 2, 3, 4, 5, and 8 bands). Coagulase gene PCR-RFLPs exhibited 10 patterns that ranged from 1 to 8 fragments with AluI digestion. Antimicrobial susceptibility testing with a panel of 8 antimicrobial agents showed 6 different antibiotypes. Antibiotype 1 was the most common phenotype with 82.7%. The results have demonstrated that many new variants of the coa gene are present in Minia, Egypt, different from those reported in the previous studies. So surveillance of MRSA should be continued. 1. Introduction MRSA was identified as a hospital acquired pathogen in the 1960s. Infections with community-acquired MRSA (CA-MRSA) have emerged in the 1980s due to the spread of MRSA from hospitals to the community [1]. A highly pathogenic community-acquired organism different from those related to hospitals has emerged since the mid-1990s [2]. The increasing rate of CA-MRSA infections in many areas, coupled with the organism’s unique pattern of virulence, clinical picture, and antimicrobial resistance, has important implications for treatment and infection control measures and acts as a serious challenge for the clinician [3]. The differentiation between CA-MRSA and hospital acquired MRSA (HA-MRSA) is becoming so difficult, since CA-MRSA could spread in hospitals [4]. Colonization is the first stage in the pathogenesis of MRSA infection. About 20% of people are considered as permanent carriers of S. aureus, mainly in the anterior nares and skin, and also axila, throat, intestine, perineum, and rectum may be colonized with S. aureus. About 30% of people are transient carriers, and 5 to 7% of them are colonized with MRSA [5]. Naturally S. aureus has shown variable genome structure that is associated with the variable strains in certain areas; those are responsible for the emerging of different epidemiologic profiles. Identification and subtyping of such strains is very