Clinical Manifestations And Prognostic Factors Of Carbapenem-resistant Klebsiella Pneumoniae Bloodstream Infection

Objective:To study the clinical characteristics of K.pneumoniae bloodstream infection,to explore its risk factors for bloodstream infection and prognostic factors of mortality caused by carbapenem-resistant K.pneumoniae(CRKP),as well as antimicrobial therapy for the strain bloodstream infection,which can provide the clinical reference for early diagnosis,control of bacterial drug resistance and treatment.Methods:(1)A 5-year retrospective study of 190 cases with K.pneumoniae bloodstream infection was conducted in Chinese People's Liberation Army(PLA)General hospital from June 2011 to August 2016.The patients were divided into two groups according to resistance to carbapenem,patients with CRKP bloodstream infections and those infected with carbapenem-susceptive K.pneumoniae(CSKP)bloodstream infections,The risk factors of CRKP bloodstream infection were identified by univariate analysis and the independently risk factors of CRKP bloodstream infections were identified by logistic regression analysis.(2)And then,according to the 28-day survival after bloodstream infection,the patients were divided into death group(n=24)and survival group(n=36),survivor and death subgroups were compared to identify predictors and independent predictors of mortality.Meanwhile,the 46 patients who received definitive treatment were divided into combination therapy group(n=32)and monotherapy group(n=14),to compare the differences between the two groups and explore the optimum antimicrobial treatment in combination group.Results:(1)There were 190 non-duplicated K.pneumoniae blood isolates identified in our research,with the overall rate of carbapenem-resistant reaching 31.6%over the past five years,about the distribution of CRKP isolates from blood sample,the Respiratory medical was the main source,followed by ICUs and Hepatobiliary surgery.In logistic regression analysis,being exposed to antibiotics(OR=5.06,95%CI 2.15-11.93,P<0.001),combination with respiratory diseases(OR=3.99,95%CI 1.49-10.7,P=0.006)and receiving indwell invasive devices(OR=26,95%CI 2.88-234.98,P=0.004)were identified as independent risk factors for CRKP bloodstream infection.(2)There were 60 non-duplicated CRKP blood isolates identified in our research,the 28-day mortality was 40%.High APACHEII score(OR=1.15,95%CI 1.0-1.3,P=0.048)was identified as independent risk factors for 28-day mortality in patients with CRKP bloodstream infection.Among the 60 patients with CRKP bloodstream infection,46 patients received definitive therapy,32 received combination schemes(including two,three or four agents),whilst 14 received monotherapy,the 28-day mortality was 34.8%.In univariate analysis,the 28-day mortality rate was similar between patients with combination and monotherapy.Among 32 patients who received combination therapy,the mortality decreased obviously when the imipenem MIC?2?g/ml.Conclusion:Carbapenem-resistant K.pneumoniae is an emerging multi-drug resistant nosocomial pathogen.Indwelling invasive devices in hospital and being exposed to antibiotics,especially carbapenem and beta-lactam/lactamase inhibitors,are associated with the produce of carbapenem-resistant strains.Bloodstream infection due to CRKP resulted in significantly increased mortality,APACHEII score as a predictor for mortality in patients with CRKP bloodstream infection.