Infection Investigation And Multi-drug-resistance Analysis Of Methicillin-resistant Staphylococcus Aureus

Staphylococcus aureus(SA) is a kind of common pyogenic coccus. Its drug-resistances bring more difficult for the clinic treatment. In order to control infection caused by SA in time, selection of sensitive antibiotics according to the result of drug- sensitive test becomes very important.We isolated 149 strains of MRSA among 206 strains of SA from clinic samples through catalase test, erythromycin glycerol test, plasma-coagulase test, ?– lactamase test, cefoxitin slip-diffusion test and detection of mecA genes by PCR. The detection rate was 72.33%. K-B method was used in drug-sensitive test, the conclusion is that the most MRSA were resistant to oxacillin, erythromycin, penicilin, cefoxitin, cefazolin, cefotaxim, ciprofloxacin, Ofloxacin, Clindamycin and gentamycin, the drug-resistant rate of MRSA to rifadin and chemitrim was lower and that of MRSA to vancocin and teicoplanin. According to RAPD electrophoregram, 149 strains of MRSA had been classified into four types, from type I to typeⅣ,and type I was dominant. By the comparison of RAPD typing and the anti-drug atlas typing, we concluded that there was not obvious causality between genetype and drug resistance. Through retrospective study, we knew that the sensitive locations to MRSA infecion were respiratory tract and wound infecion. The divisions of MRSA infective cases were mainly in ICU , tumor department, Medical Department, paediatrics and chirurgery. Most of patients had used one or more than one kind of antibiotics.This study had very important guidance significance in instituing reasonable therapeutic regimen in hospital and in controling and delaying the generation of multidrug resistant bacteria.