Determination of Serum Procalcitonin Level in Kawasaki Disease

 The most frequent cause of coronary artery aneurysm in children is Kawasaki disease (KD). Recently, limited studies on procalcitonin (PCT) were performed to find a biomarker for the diagnosis or prognosis of children with KD.

 This study aimed to compare serum PCT levels between complete and incomplete KD and testify to the predictive validity of PCT for intravenous immunoglobulin (IVIG) resistance and predicting coronary artery lesions (CALs).

 This cross-sectional study was conducted at Namazi hospital in Shiraz, Iran, in 2019. All KD patients admitted to the hospital were included, with parental consent obtained. Kawasaki disease patients were categorized as complete KD (cKD) or incomplete KD (iKD). Two-dimensional echocardiography was performed, and peripheral venous blood was examined for PCT levels and other markers. All patients received IVIG and aspirin as standard treatment. The presence of coronary artery abnormalities (CAAs) was determined based on coronary artery size and morphology. We used Stata software version 14.0 for data analysis. Logistic regression models identified predictive factors for coronary complications. This study determined the optimal PCT cut-off point for predicted coronary complications using receiver operating characteristic (ROC) curve analysis. Approval was obtained from the Research Ethics Committees of Shiraz University of Medical Sciences.

 Procalcitonin values in 38 children hospitalized with acute KD ranged from 0.2 ng/mL to 10 ng/mL, with a mean of 2.65 ng/m. There was no correlation of PCT with patients’ age or gender, incomplete KD, or IVIG resistance. The serum PCT concentration was higher in patients with CAL (P = 0.009). The best PCT cut-off value for CAL prediction was 2.5 ng/mL (corresponding sensitivity = 81.8% and specificity = 68.7%), considering CAL prevalence as the studied group.

 Supplementary research is needed to determine the sensitivity and specificity of PCT for the diagnosis and prognosis of KD. Procalcitonin might be of value in predicting which children are at increased risk for CALs to intensify therapy.