Abstract

BACKGROUND: Methicillin-resistant staphylococcus capitis (MRSC) NRCS-A clone (Multi- resistant and vancomycin-non susceptible) has been recently described as an emerging cause of nosocomial bacteremia, especially in neonatal intensive-care units (NICUs). OBJECTIVE: The objective of this study was to evaluate the antibiotic and antiseptic resistance patterns, biofilm-producing ability and the prevalence of SCCmec and ACME types among MRSC isolates as well as to check the possible presence of NRCS-A clone at Tehran's Children's Medical Center, Iran. METHODS: A total of 256 coagulase-negative Staphylococcal isolates were collected, of which 10 S. capitis isolates were obtained and tested for susceptibility against 13 antimicrobial and 3 antiseptic agents, as well as biofilm production. The presence of 15 distinct resistance genes, staphylococcal cassette chromosome mec (SCCmec), and arginine catabolic mobile elements (ACMEs) were tracked. RESULTS: Seven out of 10 S. capitis isolates were MRSC (MIC90 van=8mug/mL) and resistant to trimethoprim/sulfamethoxazole, produced biofilm, (3 as strong biofilm producers) and carried ACME types I and II. Despite the identification of mec and ccr complexes in some isolates, all the SCCmec cassettes were untypeable (UT). CONCLUSION: According to the studied features, only one isolate belonged to the NRSC-A clone. The results indicate that MRSC with high antibiotic resistance and unknown SCCmec might become a serious problem in the future for the treatment of patients, particularly children.