Epidemiology and risk factors of 28-day mortality of hospital-acquired bloodstream infection in Turkish intensive care units: a prospective observational cohort study

Abstract

Objectives: To uncover clinical epidemiology, microbiological characteristics and outcome determinants of hospital-acquired bloodstream infections (HA-BSIs) in Turkish ICU patients.

Methods: The EUROBACT II was a prospective observational multicontinental cohort study. We performed a subanalysis of patients from 24 Turkish ICUs included in this study. Risk factors for mortality were identified using multivariable Cox frailty models.

Results: Of 547 patients, 58.7% were male with a median [IQR] age of 68 [55-78]. Most frequent sources of HA-BSIs were intravascular catheter [182, (33.3%)] and lower respiratory tract [175, (32.0%)]. Among isolated pathogens (n = 599), 67.1% were Gram-negative, 21.5% Gram-positive and 11.2% due to fungi. Carbapenem resistance was present in 90.4% of Acinetobacter spp., 53.1% of Klebsiella spp. and 48.8% of Pseudomonas spp. In monobacterial Gram-negative HA-BSIs (n = 329), SOFA score (aHR 1.20, 95% CI 1.14-1.27), carbapenem resistance (aHR 2.46, 95% CI 1.58-3.84), previous myocardial infarction (aHR 1.86, 95% CI 1.12-3.08), COVID-19 admission diagnosis (aHR 2.95, 95% CI 1.25-6.95) and not achieving source control (aHR 2.02, 95% CI 1.15-3.54) were associated with mortality. However, availability of clinical pharmacists (aHR 0.23, 95% CI 0.06-0.90) and source control (aHR 0.46, 95% CI 0.28-0.77) were associated with survival. In monobacterial Gram-positive HA-BSIs (n = 93), SOFA score (aHR 1.29, 95% CI 1.17-1.43) and age (aHR 1.05, 95% CI 1.03-1.08) were associated with mortality, whereas source control (aHR 0.41, 95% CI 0.20-0.87) was associated with survival.

Conclusions: Considering high antimicrobial resistance rate, importance of source control and availability of clinical pharmacists, a multifaceted management programme should be adopted in Turkish ICUs.

Figure 1.

Relationships between antibiotic resistance and timing of appropriate antimicrobial therapy. Cumulative percentage of patients treated with at least one in vitro active antimicrobial, on each time period before and after the date of drawing of the initial positive blood culture, demonstrated by antimicrobial resistance status. In the first graph (located on the left-hand side), carbapenem resistance was interpreted among Enterobacterales, Pseudomonas spp. and Acinetobacter spp. In the second graph (located on the right-hand side), ‘resistant’ indicates the presence of methicillin resistance among coagulase-negative staphylococci spp. and Staphylococcus aureus, as well as the presence of vancomycin resistance in Enterococci spp. Closed brackets denote inclusive of the end of the range and open brackets denote the exclusion of the end of the range. *Chi-square test for linear-by-linear association was used for statistical purposes. Non-CR, non-carbapenem resistant; CR, carbapenem resistant. This figure appears in colour in the online version of JAC and in black and white in the print version of JAC.

Figure 2.

Survival curves for monobacterial Gram-negative HA-BSIs, monobacterial Gram-positive HA-BSIs and HA-BSIs requiring source control. In survival probability analysis of monobacterial Gram-negative HA-BSIs, infections caused by Stenotrophomonas maltophilia were excluded. In the middle figure for monobacterial Gram-positive HA-BSIs, ‘resistance’ indicates the presence of methicillin resistance among coagulase-negative staphylococci spp., and Staphylococcus aureus, as well as the presence of vancomycin resistance in Enterococci spp. In the survival probability analysis of source control, only patients requiring source control were considered. GN, Gram-negative; CR-GNB, carbapenem-resistant Gram-negative bacteria; GP, Gram-positive. This figure appears in colour in the online version of JAC and in black and white in the print version of JAC.