Diagnostic value of plasma procalcitonin for bacterial infection in patients receiving extracorporeal membrane oxygenation

Objective To evaluate the diagnostic value of plasma procalcitonin (PCT) for bacterial infection in patients receiving extracorporeal membrane oxygenation (ECMO). Methods Clinical data of patients receiving ECMO therapy admitted between August 2016 and January 2018 in Department of Critical Care Medicine, Tongji Hospital of Tongji Medical College were analyzed retrospectively. All patients receiving ECMO with bacterial culture were eligible for inclusion. Plasma PCT, IL-6, CRP and WBC levels detected within 24 h of bacterial cultures were analyzed immediately. Bacterial infection in ECMO was determined through bacterial culture and clinical characteristics. Finally, receiver operating characteristic (ROC) curve analysis was used to evaluate the diagnostic value of inflammatory markers for bacterial infection in ECMO patients. Results Seventeen patients met the inclusion criteria, including 15 patients with acute respiratory failure and 2 patients with acute circulatory failure. There were 37 positive bacterial cultures, and 91 plasma PCT levels were detected in the process of ECMO. Compared with IL-6, CRP and WBC, plasma PCT had significant clinical significance in the diagnosis of bacterial infection (AUC=0.818,P<0.001). The cut-off value of PCT was 1.0 ng/mL, with a sensitivity of 92% and a specificity of 43%. Conclusions Compared with other conventional inflammatory markers, plasma PCT has more diagnostic value for bacterial infection in ECMO patients. Key words: Procalcitonin; Extracorporeal membrane oxygenation; Bacteria; Infection; Diagnosis; Inflammatory markers; Respiratory failure; Circulatory failure