A Study Of Antimicrobial Resistance And Molecular Epidemiology Of Methicillin-resistant Staphylococcus Aureus

Objecive:To study the resistance of Methicillin-resistant Staphylococcus aureus(MRSA)to antibiotics and its distribution, and detect SCCmec typing of MRSA isolates.Get the message of the molecular epidemiologic characters of MRSA in our hospital and guide the treatment and prevention of MRSA infections. Methods:293 Staphylococcus aureus were isolated from the clinical samples of patients in 16 hospitals in Hubei province. To study the homology of 75 MRSA from different hospitals by using Random Amplification of Polymorphic DNA (RAPD) analysis.The characteristic genes of SCCmec typing were tested by PCR methods.The pvl gene was detected by PCR.Results: 1 .Among 293 Staphylococcus aureus, 150 were found resistant to cefoxitin, all strains were susceptible to vancomycin, teicoplanin and fusidic acid. Most of strains were multiple resistant to other antibiotics. Over 70 percent of Staphylococcus aureus were resistant to penicillin and erythromycin. Most isolates were simultaneously resistant to gentamicin, levofloxacin, erythromycin, and rifampin (70/150).;2. 25 genetypes were found in 75 MRSA by RAPD;3.Staphylococcal cassette chromosome mec (SCCmec) typing showed 67 isolates were tppeⅢ, 6 isolates typeⅢa , and 2 isolates typeⅣ.Conclusions: The antimicrobial resistance status of the Staphylococcus aureus in Hubei province is very serious. Multidrug-resistant staphylococcus aureus is very common in Hubei province. Fortunately at present we found no isolates were resistant to vancomycin,teicoplanin and fusidate acid in our province. RAPD is found rapid, sensitive and reliable, and is one of powerful epidemiologic tools to monitoring the MRSA infections. Most of MRSA were SCCmec typeⅢin Hubei province, maybe these strains are hospita-acquired MRSA.