Brain natriuretic peptide as a clinical screening tool for the diagnosis of Kawasaki disease

N-terminal pro-brain natriuretic peptide (NT-proBNP) has been studied as a diagnostic screening tool for Kawasaki disease (KD). However, brain natriuretic peptide (BNP) has been less studied while has less variability among age groups. We aimed to find out if BNP can be used as a diagnostic screening tool for KD in Korea. This was a retrospective cohort study performed in a single pediatric emergency department. Patients younger than 19 years of age who presented with fever and underwent BNP examination for suspected KD was included. The primary outcome was the diagnostic performance of BNP for KD, and the secondary outcome was the diagnostic performance of BNP for coronary artery aneurysm (CAA). We also derived a scoring system for predicting KD and CAA. Of the 778 patients who were finally included, 400 were not diagnosed with KD and 378 were diagnosed with KD. The odds ratio of BNP at the cutoff of 30 pg/mL for KD was 7.80 (95% CI, 5.67-10.73) in the univariate analysis and 3.62 (95% CI, 2.33-5.88) in the multivariable analysis. The odds ratio of BNP at the cutoff of 270 pg/mL for CAA was 3.67 (95% CI, 2.18-6.19) in the univariate analysis and 2.37 (95% CI, 1.16-8.74) in the multivariable analysis. The AUC of KD and CAA were 0.884 and 0.726, respectively, which was the highest AUCs among all variables. Additionally, we proposed a scoring system for KD and CAA. It is important to clinically suspect KD and CAA in children with high BNP levels.