Analysis Of Clinical Features Of Carbapenem Resistant Klebsiella Pneumoniae Bloodstream Infections:A Retrospective Study

Objectives:In response to the lack of effective antibiotics against Carbapenem-Resistant Klebsiella Pneumoniae(CRKP)infections,the use of tegacycline is increasing.In recent years,Tigecycline and Carbapenem-Resistant Klebsiella Pneumoniae(TCRKP)has become more and more common,but its epidemiological characteristies are still unclear.Regarded as one of the last resorts,polymyxin B has been used alternatively in China with little experience in clinical medication.We aim to identify the risk factors of TCRKP bacteremia patients among critically ill patients.Then we analyse patients suffering from CRKP bacteremia and using polymyxin B to estimate therapeutic effects with different agent timings.Methods:We searched the patients with positive CRKP bacteremia in the comprehensive ICU from March 2014 to December 2018.We collected demographic information,bacterial susceptibility test data,treatment and prognosis.All patients were divided into the normal CRKP group and the TCRKP group.Propensity score match(PSM)and variance analysis were performed to compare the clinical characteristics.In subgroup analyses,we would compared therapeutic effects between CRKP bloodstreams infections patients with different polymyxin B using timings.Results:A total of 142 patients are identified with CRKP bloodstream infection within 4 years and 55 patients with TCRKP(38.7%),40 patients using polymyxin B(28.2%).Thirty-eight pairs of patients are matched successfully with PSM.As a result,the only risk factor for TCRKP bacteremia was the history of prior tigecyclme therapy(39.45%vs.5.26%,P=0.001,OR=11.739;2.453-56.169).The mortality of patients with TCRKP bloodstream infection in 14-day mortality and 30-day mortality was not higher than that of normal CRKP group(32.73%vs.36.78%,P=0.464;36.36%vs.44.83%,P=0.348).In addition,TCRKP bloodstream infection did not increase the length of stay in ICU and the total length of hospitalization(22.2 days vs.25.4 days,P=0.532;40.7 days vs.47.4days,P=0.310).Early administration of polymyxin B includes patients receiving the drug within 48 hours of bacteremia and others belongs to delayed administration.Compared with delayed application,early use of polymyxin B-based combination therapy increased the bacterial clearance rate(65.22%versus 29.41%,P=0.025;OR=0.533)and decreased the 30-day mortality(39.13%versus 70.59%,P=0.045;OR=0.461)and overall mortality(43.48 versus 82.35%,P=0.022;OR=0.321).Polymyxin B duration and total dosages were similar in the two groups(11.57 days versus 11.76 days,P=0.919;1306.52 mg versus 1247.06 mg,P=0.711).Conclusions:Compared with normal CRKP bacteremia.prior tigecycline therapy may be the only relevant risk factor for TCRKP bloodstream infection.But given proper treatment,TCRKP bacteremia does not increase mortality or prolong the length of hospitalization.In the meanwhile,independent of drug dosage and duration,early use of polymyxin B in 48 hours as CRKP bacteremia onset can effectively eliminate bacteria,improving the 30-day mortality and the overall outcome.