Clinical Value of Whole Blood Procalcitonin Using Point of Care Testing, Quick Sequential Organ Failure Assessment Score, C-Reactive Protein and Lactate in Emergency Department Patients with Suspected Infection

Abstract

We investigated the clinical value of whole blood procalcitonin using point of care testing, quick sequential organ failure assessment score, C-reactive protein and lactate in emergency department patients with suspected infection and assessed the accuracy of the whole blood procalcitonin test by point-of-care testing. Participants were randomly selected from emergency department patients who complained of a febrile sense, had suspected infection and underwent serum procalcitonin testing. Whole blood procalcitonin levels by point-of-care testing were compared with serum procalcitonin test results from the laboratory. Participants were divided into two groups—those with bacteremia and those without bacteremia. Sensitivity, specificity, positive predictive value, negative predictive value of procalcitonin, lactate and Quick Sepsis-related Organ Failure Assessment scores were investigated in each group. Area under receiving operating curve of C-reactive protein, lactate and procalcitonin for predicting bacteremia and 28-day mortality were also evaluated. Whole blood procalcitonin had an excellent correlation with serum procalcitonin. The negative predictive value of procalcitonin and lactate was over 90%. Area under receiving operating curve results proved whole blood procalcitonin to be fair in predicting bacteremia or 28-day mortality. In the emergency department, point-of-care testing of whole blood procalcitonin is as accurate as laboratory testing. Moreover, procalcitonin is a complementing test together with lactate for predicting 28-days mortality and bacteremia for patients with suspected infection.