| 【Objective】This study through the acquisition on January 1,2019-September 1,2020 to see a doctor in the hospital ICU met inclusion and exclusion criteria of severe pneumonia in patients with lower respiratory tract specimens,select carbon penicillium alkene resistant enterobacter mesh bacteria CRE,collected the clinical data of patients,to discuss the Intensive Care Unit CRE related risk factors of severe pneumonia;Carbonapenase production and drug resistance gene of CRE were analyzed.MALDI-TOF MS was used for homology analysis to provide evidence for effective control of nosocomial infection of CRE and rational drug use.【Methods】1.The strain composition,specimen distribution and department distribution of CRE in our hospital from 2013 to 2020 were statistically analyzed.Diagnosis and death of severe CRE associated pneumonia in ICU of our hospital from 2013 to 2020.2.Analysis on January 1,2019-September 1,2020 intensive care unit CRE related clinical data of patients with severe pneumonia,choose the same time CSE related to severe pneumonia patients as control group.SPSS 22.0 software was used to analyze the risk factors.Values were considered significant at the P<0.05 level.3.The retained lower respiratory tract specimens were inoculated on the plate.Identification and drug sensitivity tests were performed using the automated VITEK2 system.Carpenenmase screening was performed using phenotypic screening test.4.Carbapenemase gene was detected by PCR.The amplified products were sequenced and compared on the Blast network.5.Homology of 57 strains of bacteria were analyzed by means of RAPD and MALDI-TOF MS.【Results】1.A total of 1483 strains of CRE strains were collected in our hospital from January 1,2013 to December 31,2020,and the main pathogens were 18.9%(1259/6660)of Klebsiella pneumoniae.The detection rate of Klebsiella pneumoniae increased rapidly from 3.71% in 2013 to 36.43% in 2020,an increase of nearly 10 times.CRE was mainly derived from respiratory specimens.A total of 564 strains of CRE were detected in intensive care unit(ICU)in 8 years,among which 87.06%(491/564)of severe CRE associated pneumonia were detected,and the mortality rate was higher(52.6%).2.Univariate analysis showed that hospitalization history,carrying other multidrug-resistant bacteria,cephalosporins,aminoglycosides,carbapenems,vancomycin,and use of antifungal agents in the past 6 months may be risk factors for CRE associated severe pneumonia in ICU.Multivariate analysis using binary Logistic regression showed that carrying other multi-drug resistant bacteria,carbapenems,and use of antifungal agents were independent risk factors for CRE associated severe pneumonia in ICU.3.All the 57 strains of CRE detected in the lower respiratory tract samples of patients with severe pneumonia in the ICU of the Affiliated Hospital of Yunnan University from January 1,2019 to September 1,2020 were infected bacteria,among which 56 strains of Klebsiella pneumoniae and 1 strain of Enterobacter cloacae were isolated.The results of MCIM combined with ECIM showed that 54 of the 57 CRE strains produced carbapenase,among which 53 strains produced serine carbapenase and1 strain produced metal-β-lactamase.4.Carbopenicillase gene detection results: all the 57 strains of CRE contained carbapenase gene,among which the positive rate of KPC-2 in class A enzyme was43.37%,the positive rate of NDM-1 in class B enzyme was 1.75%,oxa-48 in class D enzyme was 33.33%,and Vim-2 and IMP were not detected in class B enzyme.5.The results of homology analysis showed that the 57 strains of Cre were divided into 4 classes by RAPD,and class D was the main clone.The 57 strains were divided into two classes and six subclasses by MALDI-TOF MS,and class I was the main clone.6 strains(3,4,8,11,36,42)of RAPD in class A were consistent with class IIB of MALDI-TOF MS.14 strains of RAPD(9,17,20,24,25,26,27,30,38,46,47,51,53,54)in class D were consistent with those of MALDI-TOF MS in class IA.【Conclusion】1.The incidence and mortality of CRE associated severe pneumonia in ICU are high.2.Carrying other multidrug-resistant bacteria,carbapenems,and antifungal agents are independent risk factors for CRE associated severe pneumonia in ICU.3.The CRE of lower respiratory tract infection in patients with severe pneumonia in intensive care unit was mainly carbapenemase-producing Klebsiella pneumoniae.4.KPC-2 is the major carbapenemase producing gene in CRE of lower respiratory tract infection in ICU patients with severe pneumonia.5.MALDI-TOF MS is easy to operate,less time consumption and low cost,but it is not completely consistent with RAPD.Therefore,further experimental studies are needed for the application of MALDI-TOF MS in clinical strain homology analysis. |
PDF Full Text Request