title: Utility of a clinical risk factor scoring model in predicting infection with extended-spectrum β-lactamase-producing enterobacteriaceae on hospital admission.
abstract: OBJECTIVE
  To validate the utility of a previously published scoring model (Italian) to identify patients infected with community-onset extended-spectrum β-lactamase-producing Enterobacteriaceae (ESBL-EKP) and develop a new model (Duke) based on local epidemiology.
  
  
  METHODS
  This case-control study included patients 18 years of age or more admitted to Duke University Hospital between January 1, 2008, and December 31, 2010, with culture-confirmed infection due to an ESBL-EKP (cases). Uninfected controls were matched to cases (3:1). The Italian model was applied to our patient population for validation. The Duke model was developed through logistic-regression-based prediction scores calculated on variables independently associated with ESBL-EKP isolation. Sensitivities and specificities at various point cutoffs were determined, and determination of the area under the receiver operating characteristic curve (ROC AUC) was performed.
  
  
  RESULTS
  A total of 123 cases and 375 controls were identified. Adjusted odds ratios and 95% confidence intervals for variables previously identified in the Italian model were as follows: hospitalization (3.20 [1.62-6.55]), transfer (4.31 [2.15-8.78]), urinary catheterization (5.92 [3.09-11.60]), β-lactam and/or fluoroquinolone therapy (3.76 [2.06-6.95]), age 70 years or more (1.55 [0.79-3.01]), and Charlson Comorbidity Score of 4 or above (1.06 [0.55-2.01]). Sensitivity and specificity were, respectively, more than or equal to 95% and less than or equal to 47% for scores 3 or below and were less than or equal to 50% and more than or equal to 96% for scores 8 or above. The ROC AUC was 0.88. Variables identified in the Duke model were as follows: hospitalization (2.63 [1.32-5.41]), transfer (5.30 [2.67-10.71]), urinary catheterization (6.89 [3.62-13.38]), β-lactam and/or fluoroquinolone therapy (3.47 [1.91-6.41]), and immunosuppression (2.34 [1.14-4.80]). Sensitivity and specificity were, respectively, more than or equal to 94% and less than or equal to 65% for scores 3 or below and were less than or equal to 58% and more than or equal to 95% for scores 8 or above. The ROC AUC was 0.89.
  
  
  CONCLUSIONS
  While the previously reported model was an excellent predictor of community-onset ESBL-EKP infection, models utilizing factors based on local epidemiology may be associated with improved performance.
authors: Duke University Hospital, Durham, NC, USA. johnsonsw@campbell.edu
authors: Steven W
authors: SW
authors: Johnson
authors: Deverick J
authors: DJ
authors: Anderson
authors: D Byron
authors: DB
authors: May
authors: Richard H
authors: RH
authors: Drew
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015415:Biomarkers / Q000378:metabolism; D016022:Case-Control Studies; D017714:Community-Acquired Infections / Q000175:diagnosis; D003661:Decision Support Techniques; D024901:Drug Resistance, Multiple, Bacterial; D004755:Enterobacteriaceae / Q000201:enzymology; D004756:Enterobacteriaceae Infections / Q000175:diagnosis* / Q000209:etiology / Q000382:microbiology; D005260:Female; D006760:Hospitalization; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D012372:ROC Curve; D015203:Reproducibility of Results; D018570:Risk Assessment; D012307:Risk Factors; D012680:Sensitivity and Specificity; D055815:Young Adult; D018440:beta-Lactam Resistance; D001618:beta-Lactamases / Q000378:metabolism
chemical_list: D015415:Biomarkers; D001618:beta-Lactamases