Drug-resistance and genotyping of methicillin-resistant Staphylococcus aureus isolated from intensive care unit / 中华临床感染病杂志

ABSTRACT

Objective To investigate drug resistance and genotypes of methicillin-resistant Staphylococcus aureus (MRSA) isolated from intensive care unit (ICU). Methods MRSA strains were isolated from patients, medical staff and environment of hospital ICUs. Disk diffusion (K-B method) was used for drug resistance testing; Staphylococcal cassette chromosome mec (SCCmec) and Staphylococcal protein A (spa) typing methods were used for genotyping and identifying the homology. Results There were 78 strains of Staphylococcus aureus isolated including 62 isolates of MRSA, which were mainly from the burn ICU (22, 35.48%). Among 62 MRSA strains, 50 were hospital acquired strains, in which 43 isolates were of SCCmec Ⅲ, 4 of SCCmec Ⅰ and 3 of SCCmec Ⅱ. Twelve isolates could not be typed. Twenty-eight out of 37 hospital acquired isolates were typed by spa typing as SCCmec Ⅲ-t030, which belonged to the same clone. Conclusion MRSA in ICU is multi-drug resistant and SCCmec Ⅲ-t030 is the most prevalent genotype, which indicates that clinical MRSA strains and environmental MRSA strains may be homologous.