Evaluation of the Usefulness of Procalcitonin as a Biomarker for the Diagnosis of Acute Cholangitis

A Single–center Retrospective Study

Abstract

Serum procalcitonin (PCT) is a commonly used biomarker for the diagnosis of bacterial infections. We performed a single–center retrospective analysis of 122 patients diagnosed as having with acute cholangitis at our hospital to evaluate the usefulness of serum PCT for early diagnosis of acute severe cholangitis. The results of our statistical analyses revealed that the serum PCT level increased significantly as the severity grade of the cholangitis increased. The area under the curve (AUC) of the serum PCT was significantly greater than that of the white blood cell count or the serum C–reactive protein level. The serum PCT level was significantly higher in the case with bacteremia than in the cases without bacteremia. The ROC–AUC of the serum PCT level for discriminating between cases with and without bacteremia was 0.65 (P＜0.05), and the optimal cutoff value for the diagnosis of cases with bacteremia was 1.3 ng/mL. The blood platelet counts of the patients with serum PCT levels of over 1.3 ng/mL were significantly lower those of patients with serum PCT levels of under 1.3 ng/mL. A negative correlation was observed between the serum PCT level and the platelet count in both cases with mild and moderate cholangitis. Furthermore, our analyses also suggested that the optimal cutoff value of the serum PCT for predicting the need for emergency biliary drainage was 1.3 ng/mL. In conclusion, these findings suggest that the serum PCT could be a useful biomarker for early diagnosis of severe acute cholangitis.