Attributable mortality of ICU acquired bloodstream infections: a propensity-score matched analysis

International audienceThe mortality attributable to ICU-acquired bloodstream infection (BSI) differs between studies due to statistical methods used for cohort matching. Propensity-score matching has never been used to avoid eventual bias when studying BSI attributable mortality in the ICU. We conducted an observational prospective study over a 4-year period, on patients admitted for at least 48 h in 2 intensive care units. Based on risk factors for death in the ICU and for BSI, each patient with BSI was matched with 3 patients without BSI using propensity-score matching. We performed a competitive risk analysis to study BSI mortality attributable fraction. Of 2464 included patients, 71 (2.9%) had a BSI. Propensity-score matching was highly effective and group characteristics were fully balanced. Crude mortality was 36.6% in patients with BSI and 21.6% in propensity-score matched patients (p=0.018). Attributable mortality of BSI was 2.3% [1.2-4.0] and number needed to harm was 6.7. With Fine and Gray model, a higher risk for death was observed in patients with BSI than in propensity-score matched patients (sub distribution Hazard Ratio (sdHR) = 2.11; 95% CI [1.32-3.37] p = 0.002). Patients with BSI had a higher risk for death and BSI attributable mortality fraction was 2.3%

Incidence and risk factors for acquired colonization and infection due to extended-spectrum beta-lactamase-producing Gram-negative bacilli a retrospective analysis in three ICUs with low multidrug resistance rate

International audienceThe purpose of this study is to assess risk factors for the acquisition of extended-spectrum β-lactamase-producing Gram-negative bacilli (ESBL-GNB) colonization and infection (AI) in ICUs with low ESBL-GNB prevalence rate. We conducted a retrospective observational study in three ICUs in Bretagne, France. All patients admitted from January 2016 to September 2017 with a length of stay of 2 days or more were included. Universal screening for ESBL-GNB colonization was performed in all participating ICUs. Of the 3250 included patients, 131 (4.0%) were colonized at admission, 59 acquired colonization while hospitalized (1.9%; 95% CI [1.5-2.5%]), and 15 (0.5%; 95% CI [0.3-0.8%]) acquired ESBL-GNB infections. In the case of infection, the specificity and the negative predictive values of preexistent colonization for the ESBL-GNB etiology were 93.2% [91.5-95.1%] and 95.2% [93.5-97.1%], respectively. Colonization was the main risk factor for ESBL-GNB AI (OR = 9.61; 95% CI [2.86-32.29]; p < 0.001). Antimicrobial susceptibility of non-ESBL-GNB isolates responsible for AI was similar for any non-carbapenem β-lactam (95%) and imipenem (94%). ESBL-GNB AIs were rare in ICUs with low ESBL-GNB prevalence rate. Prior colonization was the main risk factor for subsequent infection. Empirical carbapenem therapy could be avoided in non ESBL-GNB colonized patients with suspected AI