Development and validation of the INCREMENT-ESBL predictive score for mortality in patients with bloodstream infections due to extended-spectrum-β-lactamase-producing Enterobacteriaceae

[Background] Bloodstream infections (BSIs) due to ESBL-producing Enterobacteriaceae (ESBL-E) are frequent yet outcome prediction rules for clinical use have not been developed. The objective was to define and validate a predictive risk score for 30 day mortality.
[Methods] A multinational retrospective cohort study including consecutive episodes of BSI due to ESBL-E was performed; cases were randomly assigned to a derivation cohort (DC) or a validation cohort (VC). The main outcome variable was all-cause 30 day mortality. A predictive score was developed using logistic regression coefficients for the DC, then tested in the VC.
[Results] The DC and VC included 622 and 328 episodes, respectively. The final multivariate logistic regression model for mortality in the DC included age >50 years (OR = 2.63; 95% CI: 1.18–5.85; 3 points), infection due to Klebsiella spp. (OR = 2.08; 95% CI: 1.21–3.58; 2 points), source other than urinary tract (OR = 3.6; 95% CI: 2.02–6.44; 3 points), fatal underlying disease (OR = 3.91; 95% CI: 2.24–6.80; 4 points), Pitt score >3 (OR = 3.04; 95 CI: 1.69–5.47; 3 points), severe sepsis or septic shock at presentation (OR = 4.8; 95% CI: 2.72–8.46; 4 points) and inappropriate early targeted therapy (OR = 2.47; 95% CI: 1.58–4.63; 2 points). The score showed an area under the receiver operating curve (AUROC) of 0.85 in the DC and 0.82 in the VC. Mortality rates for patients with scores of
[Conclusions] We developed and validated an easy-to-collect predictive scoring model for all-cause 30 day mortality useful for identifying patients at high and low risk of mortality.
This study was funded by: the Ministerio de Economía y Competitividad, Instituto de Salud Carlos III co-financed by the European Development Regional Fund ‘A way to achieve Europe’ ERDF, the Spanish Network for Research in Infectious Diseases (REIPI RD12/0015), FIS grant PI10/02021 and FIS grant PI14/01832. B. G. G., J. R. B., A. P. and Y. C. also received funds from the COMBACTE-CARE project, Innovative Medicines Initiative (IMI), the European Union’s Seventh Framework Programme (FP7/2007-2013) and in-kind contributions from EFPIA companies. R. A. B. was also supported in part by funds and/or facilities provided by the Cleveland Department of Veterans Affairs, the Veterans Affairs Merit Review Program and the Geriatric Research Education and Clinical Center VISN 10 (VISN 10 GRECC), and the NIAID of the NIH under award numbers R01AI072219 and R01AI063517.