Soluble urokinase plasminogen activator receptor and procalcitonin for risk stratification in patients with a suspected infection in the emergency department: a prospective cohort study

Abstract

Background and importance Early identification of patients at risk of clinical deterioration may improve prognosis of infected patients in the emergency department (ED). Combining clinical scoring systems with biomarkers may result in a more accurate prediction of mortality than a clinical scoring system or biomarker alone. Objective The objective of this study is to investigate the performance of the combination of National Early Warning Score-2 (NEWS2) and quick Sequential Organ Failure Assessment (qSOFA) score with soluble urokinase plasminogen activator receptor (suPAR) and procalcitonin to predict 30-day mortality in patients with a suspected infection in the ED. Design, settings and participants This was a single-center prospective observational study, conducted in the Netherlands. Patients with suspected infection in the ED were included in this study and followed-up for 30 days. The primary outcome of this study was all cause 30-day mortality. The association between suPAR and procalcitonin with mortality was assessed in subgroups of patients with low and high qSOFA (<1 and ≥1) and low and high NEWS2 (<7 and ≥7). Main results Between March 2019 and December 2020, 958 patients were included. A total of 43 (4.5%) patients died within 30 days after ED visit. A suPAR ≥ 6 ng/ml was associated with an increased mortality risk: 5.5 vs. 0.9% (P < 0.01) in patients with qSOFA = 0 and 10.7 vs. 2.1% (P = 0.02) in patients with qSOFA ≥ 1. There was also an association between procalcitonin ≥0.25 ng/ml and mortality: 5.5 vs. 1.9% (P = 0.02) for qSOFA = 0 and 11.9 vs. 4.1% (P = 0.03) for qSOFA ≥ 1. Similar associations were found within patients with a NEWS < 7 (5.9 vs. 1.2% for suPAR and 7.0 vs. 1.7% for procalcitonin, P < 0.001). Conclusion In this prospective cohort study, suPAR and procalcitonin were associated with increased mortality in patients with either a low or high qSOFA and patients with low NEWS2.