The C-Reactive Protein to Albumin Ratio as a New Predictor for Bacterial Culture in Patients with Severe Sepsis and Septic Shock: A Single-Center Retrospective Analysis.

Abstract

Background: Severe sepsis and septic shock with a high mortality rate are common critical illnesses in the emergency department. Early detection and intervention are a key to improve patient outcomes. The CAR is a fresh inflammation-based prognostic score and widely used in clinics. The primary aim of this study was to investigate the relationship between CAR and blood culture. Methods: 331 adult subjects admitted to the Emergency Intensive care unit via the emergency department from December 1, 2018 to June 30, 2020 were included in this analysis. The study population was divided into positive group and negative group according to the results of blood culture, ROC curves was used to assess the diagnostic performance of CAR, PCT and other risk factors for predicting blood culture, and Youden’s index derived cut-offs were calculated. Results: The patients were subdivided into the positive group and the negative group, 72 cases and 259 cases, respectively. The university analysis indicated that admission PCT, review of PCT, CAR, hepatobiliary system infection, urinary tract infection (relative to lung infection) was significantly corelated with the risk of bloodstream infection. Albumin was negatively correlated with the risk of bloodstream infection. A prediction value of CAR>5 was a significant marker in predicting bloodstream infection (sensitivity:50%; specificity: 71.43%; PPV32.73%; NPV83.71%; P<0.001). Admission PCT and reviewed PCT exhibited greater predictive significance compared with CRP or CAR. At a cut-off of 3.98 ng/ml, reviewed PCT offered the best accuracy in predicting bloodstream infection with the sensitivity, specificity, PPV, and NPV of 84.72%,54.83%, 34.08% and 92.76%; There was no difference in hospital stay and 28-day mortality between the two groups.Conclusion: A higher CAR is associated with increased incidence of bloodstream infection in patients with severe sepsis and septic shock.