Epidemiological And Clinical Features Of HVISA And VISA In Chongqing

Background The sensitivity of staphylococcus aureus to vancomycin began to decline with the widespread use of vancomycin in the treatment of methicillin-resistant staphylococcus aureus(MRSA).heterogeneous vancomycin intermediate resistant Staphylococcus aureus(hVISA)and vancomycin-intermediate resistant Staphylococcus aureus(VISA)were reported worldwide and caused the wide attention of the world.Many countries and areas have carried out relevant epidemiological investigation and research report,but its prevalence is not the same in different regions,the research about the clinical outcome of the infection also insufficiently thorough and extensive.In addition,there is no simple and effective method for clinical screening of hVISA and VISA.Modified population-analysis profile-area under the curve(PAP-AUC)is the most accurate detection method of hVSIA.Although a small number of regions in China have conducted research on hVISA,the prevalence of hVISA in chongqing is unclear.To study the prevalence of hVISA in chongqing and analyze its clinical features can provide some theoretical guidance for the clinical application of vancomycin in the region.Objective To investigate the prevalence and clinical characteristics of hVISA in Chongqing.Methods Clinical isolates were collected from the First Affiliated Hospital of Chongqing Medical University during the period from 2012-2015 and were tested for susceptibility to vancomycin using agar dilution method.Results were analyzed according to CLSI 2016 breakpoints.The population analysis profile-area under the curve(PAP-AUC)was conducted for hVISA and VISA screening;Clinical data of 105 patients infected with staphylococcus aureus were retrospectively collected.Results A total of 105 patients were included in this analysis.Methicillin-resistant strains in S.aureus(MRSA)accounted for 58.1%of 105 clinical isolates;The MIC of MRS A to vancomycin is mostly<2mg/L,and no MIC drift is seen;19 hVISA(18.1%)and 10 VISA(9.5%)were detected;and the MIC of 10 VISA were between 4～8μg/mL;there were 52 cases of nosocomial infection and 53 cases of community infection,the Methicillin-resistant strains in nosocomial infection(36 cases,69.2%)were more than community infection(25 cases,47.2%)(P<0.05);There was no significant difference in hVISA positive rates between community infection(11 cases,20.8%)and hospital infection(8 cases,15.4%)(P>0.05);the clinical outcome(P>0.05)and hospital stays(P>0.05)did not show significant difference between hVISA and VSSA;the clinical outcome(P>0.05)and hospital stays(P>0.05)did not show significant difference between VISA and VSSA.Conclusions The positive rate of hVISA is high in Chongqing.However,the hospitalization time of hVISA infection was not found to be prolonged in patients,and there did infection.It is suggested that the decrease of hVISA’s susceptibility to show higher mortality in hVISA antibacterial drugs may not affect the prognosis of patients.