Low 30-day mortality and low carbapenem-resistance in a decade of Acinetobacter bacteraemia in South Sweden.

BACKGROUND: The aim of this study was to provide a descriptive account of carbapenem resistance and risk factors for mortality from invasive Acinetobacter infections in the south of Sweden. METHODS: Blood isolates with growth of Acinetobacter species between 2010 and 2019 in Skåne county were subtyped using MALDI-TOF and subjected to susceptibility testing against clinically relevant antibiotics. Association between risk factors and 30-day mortality were analysed in univariate and multivariate logistic regression models. RESULTS: There were 179 bacteraemia episodes in 176 patients included in the study. The 30-day all-cause mortality was 16%. In all, two percent of Acinetobacter strains were carbapenem resistant. Independent risk factors associated with 30-day mortality in the multivariate regression model were Acinetobacter growth in all blood cultures drawn at the day of bacteraemia onset (OR 5.0, 95% CI: 1.8 to 13.7, p= 0.002), baseline functional capacity (1-4 points, OR 2.0, 95% CI: 1.2 to 3.4, p= 0.010) and correct empiric antibiotics at time of culture (OR 3.5 95% CI: 1.0 to 11.8, p= 0.045). CONCLUSION: This study on Acinetobacter bacteraemia in South Sweden found low 30-day mortality and low carbapenem-resistance rates compared to previous international studies which may be due to a higher rate of contaminant findings.

Performance of plasma measurement of neutrophil gelatinase-associated lipocalin as a biomarker of bacterial infections in the intensive care unit.

PURPOSE: To assess the value of dimeric neutrophil-gelatinase associated lipocalin (NGAL) as an early marker of bacterial infection and its response to antibiotic therapy in intensive care unit (ICU) patients. MATERIALS & METHODS: We measured daily plasma dNGAL in 198 patients admitted to a mixed ICU. Likelihood of infection was determined with International Sepsis Forum criteria. We measured dNGAL in 145 healthy controls to establish normal values. RESULTS: ICU patients had higher dNGAL than healthy controls. A suspected or confirmed infection was independently associated with 90% (95% CI 15-215%) higher dNGAL than absence of infection. We observed no association between acute kidney injury and dNGAL. Diagnostic accuracy at antibiotic treatment initiation, assessed with area under the receiver-operating characteristics curve (AUC-ROC), for dNGAL was 0.70 (95% CI 0.60-0.79). AUC-ROC for dNGAL 24 h before antibiotic treatment initiation was 0.54 (95% CI 0.41-0.66). The mean (95% CI) change of dNGAL in the first 2 days after appropriate antibiotic therapy initiation was -31 (-49,-13)%. CONCLUSIONS: In our cohort of ICU patients, plasma dNGAL was associated with presence of bacterial infections independent of AKI but it performed poor as a predictor of infections. Following antibiotic therapy, dNGAL markedly decreased-supporting further exploration of dNGAL-guided antibiotic de-escalation.

Calprotectin as an early biomarker of bacterial infections in critically ill patients: an exploratory cohort assessment.

BACKGROUND: Calprotectin is the most abundant protein in the cytosolic fraction of neutrophils, and neutrophil degranulation is a major response to bacterial infections. OBJECTIVES: To assess the value of plasma calprotectin as an early marker of bacterial infections in critically ill patients and compare it with the corresponding values for procalcitonin (PCT), C-reactive protein (CRP) and white blood cell count (WBC). METHODS: We measured daily plasma calprotectin levels in 110 intensive care unit patients using a newly developed turbidimetric assay run on clinical chemistry analysers. The likelihood of infection was determined according to the International Sepsis Forum criteria. RESULTS: Overall, 58 patients (52.7%) developed a suspected or confirmed bacterial infection. Plasma calprotectin predicted such infections within 24 hours with an area under the receiver operating characteristics curve (ROC area) of 0.78 (95% CI, 0.68-0.89). The ROC area for calprotectin was significantly greater than the corresponding ROC areas for WBC (P < 0.001) and PCT (P = 0.02) but only marginally better than the ROC area for CRP (0.71; 95% CI, 0.68-0.89). CONCLUSION: Plasma calprotectin appears to be a useful early marker of bacterial infections in critically ill patients, with better predictive characteristics than WBC and PCT.

Plasma endostatin may improve acute kidney injury risk prediction in critically ill patients.

BACKGROUND: Breakdown of renal endothelial, tubular and glomerular matrix collagen plays a major role in acute kidney injury (AKI) development. Such collagen breakdown releases endostatin into the circulation. The aim of this study was to compare the AKI predictive value of plasma endostatin with two previously suggested biomarkers of AKI, cystatin C and neutrophil gelatinase-associated lipocalin (NGAL). METHODS: We studied 93 patients without kidney disease who had a first plasma sample obtained within 48 h of ICU admission. We identified risk factors for AKI within the population and designed a predictive model. The individual ability and net contribution of endostatin, cystatin C and NGAL to predict AKI were evaluated by the area under the receiver operating characteristics curve (AUC), likelihood-ratio test, net reclassification improvement (NRI) and integrated discrimination improvement (IDI). RESULTS: In total, 21 (23 %) patients experienced AKI within 72 h. A three-parameter model (age, illness severity score and early oliguria) predicted AKI with an AUC of 0.759 (95 % CI 0.646-0.872). Adding endostatin to the predictive model significantly (P = 0.04) improved the AUC to 0.839 (95 % CI 0.752-0.925). In addition, endostatin significantly improved risk prediction using the likelihood-ratio test (P = 0.005), NRI analysis (0.27; P = 0.04) and IDI analysis (0.07; P = 0.04). In contrast, adding cystatin C or NGAL to the three-parameter model did not improve risk prediction in any of the four analyses. CONCLUSIONS: In this cohort of critically ill patients, plasma endostatin improved AKI prediction based on clinical risk factors, while cystatin C and NGAL did not.