Study On Antimicrobial Resistance And The Detection Of Staphylococcus Chromosomal Cassette Mec Typing Of Methicillin-resistant Staphylococcus Aureus

Staphylococcus aureus (S.aureus) is one of the most common streptococcuspyogenes and is the important source for the spread of nosocomial infection.Most ofthem are drug-resistant strains and can cause life-threatening systemic diseases. Inparticular,Methicillin-resistant S.aureus (MRSA)，make it even more difficult totreatment clinical infections. In the past few decades since the first case of MRSAwere discovered,Scope of MRSA infection has spread to all over the world and theprevalence rate is rising.Objective:To understand the molecular epidemiology and drug resistance ofmethicillin-resistant S.aureus (MRSA) from jilin city district and to provideimportant basis for guiding the clinical medication and prevention of the MRSAinfection.Methods:103strains of MRSA strains from a third rate hospital clinical detection ofjilin city since2013.7~2014.7were selected. The polymerase chain reaction (PCR)technology and multiple polymerase chain reaction were used to detect collect mecAgene and SCCmec genotype of MRSA,respectively. The drug sensitivity test ofcollectted strains for13kinds of clinical common antibacterial drugs were detectedby using the K-B method.Results:1. According the separation rate, the highest was form specimens (69.9%) andthe second is pus discharge (22.3%). According the distribution departments, the topthree are neurosurgery(31.1%), intensive care unit(19.4%), burn and plasticsurgeryreceptively(17.5%).2. All103MRSA strains are positive by MecA genetest.SCCmec genetic typing results show that SCCmec Ⅲ type strains were62 strains，accounted for60.2%；SCCmec Ⅱ type strain were39strains，accounted for37.9%；Failed to parting strains have2strains，accounted for1.9%.3. Drugsusceptibility test results showed, all of103MRSA strains are resistant to cefoxitin,cefazolin, penicillin and benzene a total of100%; The resistant rate toerythromycin, levofloxacin, ciprofloxacin, tetracycline, gentamicin and rifampinwere96.1%,93.2%,95.1%,91.3%,90.3%and55.3%receptively；The resistant rateto paediatric compound sulfamethoxazole was only1.9%, The resistant strains tovancomycin and teicoplanin were not detected.Conclusion:1. It is clear that the respiratory tract is the main site of MRSA infection and theinfection occurred mainly in the department of neurosurgery、 ICU and burncosmetic surgery.2. It is first time to clear that the SCCmec Ⅲ type is the mainMRSA epidemic strains in the jilin city district.3. The antibiotic resistance of MRSAis a serious problem and shows the multiple drug resistance in Jilin city district. thestudy does not find the isolates which are resistant to vancomycin andteicoplanin.