NT-pro BNP:A new diagnostic screening tool for Kawasaki disease

Lee, Hyunju; Kim, Heejung; Kim, Hae Soon; Sohn, Sejung

Abstract

PURPOSE: The purpose of this study was to determine whether N-terminal fragment of B-type natriuretic peptide(NT-proBNP) may be used to differentiate acute Kawasaki disease(KD) from other clinically similar diseases.
METHODS
Using electrochemiluminescence immunoassay, NT-proBNP concentrations were measured in the acute phase within 10 days after the onset of KD(n=58) and in the convalescent phase, 60 to 81 days after the onset(n=51), and also in patients with acute febrile disease as a control(n=34). Echocardiography was performed to detect pericardial effusion(PE) and coronary artery lesions(CAL), and to measure the left ventricular dimension at diastole(LVIDd) and ejection fraction(LVEF). The cutoff value of NT-proBNP for separating KD from other diseases was determined.
RESULTS
NT-proBNP concentration in the acute phases of KD was significantly higher than that in the control group(1,501.6+/-2,132.6 vs. 139.0+/-88.8 pg/mL, P<0.0001). In KD patients, NT-proBNP was elevated in the acute phase and was lowered in the convalescent phase(1,466.0+/-2,173.2 vs. 117.5+/-95.5 pg/mL, P<0.0001). The cutoff value of 260 pg/mL discriminated KD patients from other patients, with a sensitivity of 93 percent and a specificity of 88 percent. The NT-proBNP was higher in patients with PE(n=17) compared with those without PE(n=41)(1,784.2+/-1,903.1 vs. 1,384.4+/-2,232.6 pg/mL, P=0.52). Comparison of NT-proBNP could not be done between patients with CAL and those without, owing to a small number of patients with CAL(n=3). There was no correlation between NT-proBNP and LVEF index(r=0.104, P=0.46) or LVIDd index(r=0.171, P=0.22).
CONCLUSION
NT-proBNP increases in the acute phase of KD and decreases to within normal range in the convalescent phase. NT-proBNP >260 pg/mL may be highly suggestive of acute KD. NT-proBNP may be used as a diagnostic tool for KD.