Study On Risk Factors And Clinical Outcomes Of Hospital-acquired Methicillin-resistant Staphylococcus Aureus Infection In Chongqing

Objective:To summary the clinical features and outcomes of hospital-acquired methicillin-resistant Staphylococcus aureus(MRSA)infection in Chongqing area,so as to explore its risk factors and predictors of mortality.The results will provide the basis for the prevention and control of hospital-acquired MRSA infection in medical institutions,guide clinicians to recognize high-risk patients as early as possible and take active measures to improve the prognosis of patients.Methods:(1)Clinical data of patients who were hospitalized in the Southwest Hospital in Chongqing from January 1,2018 to December 31,2018 and confirmed as hospital-acquired Staphylococcus aureus infection were collected.The above patients were divided into MRSA infection group(MRSA group)and methicillin-susceptible Staphylococcus aureus infection group(MSSA group)according to the resistance of the strains to cefoxitin.Meanwhile,with reference to their age,gender and ward distribution of patients in the MRSA and MSSA groups,300 non-Staphylococcus aureus infection patients(potential hospital-acquired Staphylococcus aureus infection risk)who were hospitalized at the same time were selected as control group.The risk factors for hospital-acquired MRSA infection were analyzed by univariate and multivariate logistic regression in a case-case-control study.(2)The above-mentioned patients infected with hospital-acquired MRSA were divided into death group and survival group according to the prognosis.Univariate and multivariate nonconditional logistic regression analysis methods were used to explore the predictors of mortality in a case-control study.Result:(1)A total of 590 patients with hospital-acquired Staphylococcus aureus infection were included,251 of whom were hospital-acquired MRSA infection.The detection rate of hospital-acquired MRSA infection was 42.5%.The most common infection type was wound and soft tissue infection(155 cases,61.8%),followed by respiratory tract infection(51 cases,20.3%)and blood infection(24 cases,9.6%).The main distribution departments were burn department(98 cases,39.0%),orthopedics department(32 cases,12.7%),thoracic surgery department(17 cases,6.8%).The multivariate logistic regression showed that presence of central venous catheter(OR,1.932;95% CI,1.074-3.477;P=0.028),sputum aspiration(OR,2.887;95% CI,1.591-5.240;P<0.001)and hospital stays longer than 30 days(OR,3.067;95% CI,2.063-4.559;P<0.001)were independent risk factors for hospital-acquired MRSA infection.The mortality rate of MRSA group was 27.5%,which was higher than that of MSSA group(17.1%,P=0.002)and control group(16.0%,P=0.000).(2)Among 251 patients with hospital-acquired MRSA infection,69 cases(27.5%)died and 182 cases(72.5%)had a good prognosis.Multivariate analysis showed that renal insufficiency(OR,2.744;95% CI,1.089-6.914;P=0.032)and use of immunosuppressants(OR,3.140;95% CI,1.284-7.678;P=0.012)were the independent predictor for mortality.Empirical antibiotic use(OR,0.514;95% CI,0.282-0.935;P=0.029)can play a protective role for the patients infected with MRSA.Conclusion:Hospital-acquired MRSA infection had high rates of morbidity and mortality rate.Presence of central venous catheter,sputum aspiration,and hospital stays longer than 30 days were independent risk factors for MRSA infection.Renal insufficiency and use of immunosuppressant were the independent predictors of mortality in patients with MRSA,while empirical antibiotic use can play a protective role.