Research On MecA/icaA/icaD Gene And Pathogenicity Of Staphylococcus Epidermidis Isolated From Prostatitis

BackgroundStaphylococcus epidermidis is considered as human microbiome presents no pathogenicity during a long time,but the detection rate of Staphylococcus epidermidis in clinical specimens collected from our hospital has reached approximately thirty percent.The possible cause of Staphylococcus epidermidis accounts for prostatitis is urease and alkaline phosphatase,produced by Staphylococcus epidermidis,which can damage the pH balance of prostate,combined with the adhesive attraction to epithelial cell of human urinary tract,The foregoing effects are probably one of causes why chronic prostatitis is so difficult to be healed.Due to the absence of diagnostic gold standard and curative effect evaluation system belong to prostatitis,neither of doctors and patients are satisfied with the efficacy.So we are intended to provide scientific evidence for diagnostics and treatment of prostatitis through investigating the correlation between mecA/gyrA/icaA/icaD carrying condition and pathogenicity of Staphylococcus epidermidis.Objective1.To provide evidence for antibiotic therapy through resistance features investigation of Staphylococcus epidermidis isolated from expressed prostatic secretions in our hospital during 2013~2015.2.To exemplify the resistance mechanism of Staphylococcus epidermidis resistant isolates by screening the carrying condition of mecA/gyr A gene among them.3.By investigating the relationship between icaA/icaD carrying condition and human leukocyte elastase assay and analyzing correlation of gene carrying condition and pathogenicity of Staphylococcus epidermidis,provide tentative evidence for clinical diagnostics and treatment.Method1.Retrospective investigation was applied to Staphylococcus epidermidis detection rate in expressed prostatic secretions specimens from Yellow River Sanmenxia Hospita during 2013~2015.VITEK-2 Compact automatic bacteria identification and susceptibility system,combined with GP identification card and GP67 susceptibility card,were used for identification and regular antibiotic susceptibility analysis,and WHONET 5.6 software for antibiotic resistance analysis.2.Leukocyte elastase assay was completed by ELISA3.mecA/gyr A/icaA/icaD gene amplification was completed by PCR4.Relationship between mecA and antibiotic resistance as well as correlation of icaA/icaD and pathogenicity completed by SPSS 17.0.Result1.657 Staphylococcus epidermidis strains were isolated from expressed prostatic secretions specimens from Yellow River Sanmenxia Hospital during 2013 ~ 2015 and resistance rate raised year by year.The detection rate of Methicillin Resistant Staphylococcus epidermidis(MRSE)and Methicillin Sensitive Staphylococcus epidermidis(MSSE)were 84.38%(555/657)and 15.62%(102/657)respectively.The resistance rate of MRSE to PenicillinG,Oxacillin,Gentamicin,Ciprofloxacin,Levofloxacin,moxifloxacin,Trimethoprim/ sulfamethoxazole(SXT),Clindamycin,Erythromycin,Nitrofurantoin,Tetracycline was higher than MSSE except Rifampin,and significant difference existed between both of them(P<0.05).2.The mecA gene expression was leading resistance mechanism accounts for Methicillin Resistant Staphylococcus epidermidis(MRSE).One of the main resistance mechanisms of fluoroquinolones is the mutation of the gyrA gene.3.Positive correlation was confirmed between IcaA/icaD carrying rate and expressed prostatic secretions Leukocyte elastase assay by statistical analysis.Conclusion1.Bacteria isolated from expressed prostatic secretions were mainly MRSE and showed multi-drug resistance in most strains.Furthermore,significant difference existed between MRSE and MSSE in terms of resistance condition.2.mecA gene detection rate in Staphylococcus epidermidis was rather high and related to resistance condition.The gene gyr A mutation is involved in bacterial resistance to quinolone drugs.3.Detection rate of icaA/ica D gene in Staphylococcus epidermidis isolated from expressed prostatic secretions was relatively low,but icaA/icaD gene detection and expressed prostatic secretions leukocyte elastase assay were instrumental to diagnosis of prostatitis.