title: Risk factors for bacteriuria with carbapenem-resistant Klebsiella pneumoniae and its impact on mortality: a case-control study.
abstract: BACKGROUND
  The objective of this study was to evaluate the mortality of and risk factors for bacteriuria due to carbapenem-resistant Klebsiella pneumoniae (CRKp) versus carbapenem-susceptible K. pneumoniae (CSKp) producing extended spectrum β lactamase (ESBL).
  
  
  METHODS
  This was a retrospective case-control study in which 135 case-patients with bacteriuria due to CRKp were compared with 127 control patients with CSKp producing ESBL. In a first step, multivariate Cox regression and Kaplan-Meier survival analysis models were used to determine the difference in mortality between the two groups and risk factors for mortality. In a second step, a univariate analysis was used to identify risk factors for CRKp colonization.
  
  
  RESULTS
  There were no significant demographic or clinical differences between the groups. In-hospital mortality in the study and control groups was 29 and 25 %, respectively (non-significant difference). Multivariate analysis revealed that the most important risk factor for mortality in both groups was being bed ridden [hazard ratio 2.2, 95 % confidence interval (CI) 1.23-3.93; P = 0.008]. Patients with CRKp bacteriuria had a longer hospitalization time with a mean ± standard deviation of 28 ± 33 days compared to 22 ± 28 days in the control group (P < 0.05). Several univariate risk factors for acquiring CRKp bacteriuria were identified: antibiotic use [odds ratio (OR) 1.93, 95 % CI 1.18-3.17, p = 0.008], especially colistin (OR 2.04, 95 % CI 1.04-4.02; P = 0.036), presence of a urinary catheter (OR 2.09, 95 % CI 1.2-3.63; P = 0.008), surgery (OR 3.94, 95 % CI 1.85-8.37; P = 0.0002), invasive procedures (OR 3.06, 95 % CI 1.61-5.8; P = 0.0004), and intensive care unit admission (OR 2.49, 95 % CI 1.18-5.37; P = 0.015).
  
  
  CONCLUSIONS
  Bacteriuria caused by CRKp as compared that caused by CSKp was not found to be a risk factor for death.
authors.affiliation: Infectious Disease Unit, Shaare Zedek Medical Center, Jerusalem, Israel.
authors.forename: S
authors.initials: S
authors.lastname: Shilo
authors.forename: M V
authors.initials: MV
authors.lastname: Assous
authors.forename: T
authors.initials: T
authors.lastname: Lachish
authors.forename: P
authors.initials: P
authors.lastname: Kopuit
authors.forename: T
authors.initials: T
authors.lastname: Bdolah-Abram
authors.forename: A M
authors.initials: AM
authors.lastname: Yinnon
authors.forename: Y
authors.initials: Y
authors.lastname: Wiener-Well
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001437:Bacteriuria / Q000382:microbiology / Q000401:mortality*; D015780:Carbapenems / Q000494:pharmacology*; D016022:Case-Control Studies; D003091:Colistin / Q000009:adverse effects; D016001:Confidence Intervals; D005260:Female; D017052:Hospital Mortality; D006801:Humans; D007362:Intensive Care Units; D053208:Kaplan-Meier Estimate; D007710:Klebsiella Infections / Q000188:drug therapy / Q000401:mortality*; D007711:Klebsiella pneumoniae / Q000187:drug effects*; D007902:Length of Stay / Q000706:statistics & numerical data; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D016016:Proportional Hazards Models; D012189:Retrospective Studies; D012307:Risk Factors; D016896:Treatment Outcome; D062885:Urinary Catheters / Q000382:microbiology; D055815:Young Adult; D018440:beta-Lactam Resistance
chemical_list: D015780:Carbapenems; D003091:Colistin