Study On Clinical Characteristic And Molecular Epidemiology Of Carbapenem-resistant Klebsiella Pneumoniae In Patients With Clinical Infection

Objective CRKP to common antibiotics in hospitalized patients at the Tianjin Medical University General Hospital.To investigate the clinical characteristics,infection-related risk factors,prognosis and molecular epidemiological characteristics of hospitalized patients infected with CRKP,so as to guide clinicians to make reasonable therapeutic schedule and effectively control the spread of drug-resistant strains in hospital.Methods A total of 67 CRKP isolated from patients with clinical infections during January and December 2017 were collected from Tianjin Medical University General Hospital,and the duplicate strain was eliminated.Vitek2 compact automatic microbiological analysis system combined with K-B was used for the antimicrobial susceptibility test.The specimen type,department source and drug susceptibility test results were analyzed;1:1 case-control study was designed.Risk factors related to infection and prognosis were analyzed by univariate and multivariate Logistic regression,Clinical data of patients infected with CRKP were retrospectively analyzed,including age,gender,inpatient department,basic diseases,length of stay,invasive procedures,status of antibiotic use within the last 3 months,and patient outcomes after treatment,etc;Molecular epidemiological characteristics of CRKP isolated from our hospital were analyzed by PFGE and MLST.Results(1)A total of 67 strains of CRKP were isolated in our hospital,and most of them were infected in middle-aged and elderly patients.The top three departments were NICU(34.3%),GICU(25.4%)and neurosurgery(7.5%).The main types of infection specimens were sputum specimens from the lower respiratory tract;The resistance rate of Kp was more than 95% to cefazolin,ceftriaxone,piperacillin/tazobactam,cefoperazone/sulbactam,imipenem,ertapenem,and aztreonam,and the 67 strains of CRKP have certain sensitivity to tigecycline,polymyxin,compound sulfamethoxazole and amikacin.(2)Multivariate Logistic regression analysis showed that diabetes mellitus(OR=0.18,95%CI:0.04-0.77),mechanical ventilation(OR=0.08,95%CI:0.02-0.44)and combined antibioticswere(OR=0.05,95%CI : 0.01-0.27)were independent risk factors of CRKPinfection;The mortality rate of CRKP infectiona was 26.76%,renal disease(OR=27.09,95%CI:1.99-369.27)and neurological disease(OR=288.59,95%CI:2.24-37122.21)were independent risk factors for death from CRKP infection.(3)The 67 CRKP strains were divided into 14 PFGE clone types(A~N),and the two most predominant ones were type A and type D,in which type A accounted for35.8%(24/67)and type D for 16.4%(11/67)of all the clones.A total of 35 CRKP strains from A and D clones were analyzed by MLST.ST11(25/35)was the dominant type,including all the A clone strains,and was the main epidemic type in our hospital.D type is mainly divided into ST721(7/35)and ST36(3/35).(4)A total of 848 cases of non-repeat Kp were detected in our hospital in 2017,and the separation rate of CRKP was 7.9%.ST11 type(group A)is the main epidemic type in our hospital.The main departments are GICU ward(68.0%)and geriatric ward(12.0%),and Other departments also have scattered distribution of ST11 type;ST721and ST36(group D)have small outbreaks in NICU wards.Conclusion The resistance rate of CRKP to common antimicrobial agents such as betacylamide and betacylamide enzyme inhibitor complex is higher,and the resistance rate to tegacycline,polymyxin,compound xinnomin and amikacin is lower.Diabetes,mechanical ventilation and combination of antibiotics are risk factors for CRKP infection,Infected patients have a poor prognosis.Patients with clinical infection should be treated with a combination of drugs to improve outcomes according to the results of drug susceptibility test,and the combination of tigecycline,polymyxin and fosfomycin as core drugs.A and D clones are the main epidemic types of CRKP in our hospital.ST11(group A)CRKP has an outbreak in our hospital,mainly in GICU wards and geriatric wards,which should be highly valued by the hospital infection control department.Implement antibiotic grading management system,monitor departments at high risk of infection,disinfect department environment and isolate infected patients,so as to reduce the infection and transmission of CRKP.