Pro-brain natriuretic peptide (ProBNP) levels in North Indian children with Kawasaki disease

The diagnosis of Kawasaki disease (KD), a common pediatric vasculitis, is based solely on clinical criteria. There is a need for a robust laboratory marker that can help differentiate KD from other acute, febrile, childhood illnesses and also to predict cardiac involvement. We conducted a cross-sectional study of 25 consecutive patients admitted with diagnosis of KD from January 2013 to April 2014 and compared them with age- and sex-matched febrile controls. We studied the serum pro-brain natriuretic peptide (ProBNP) [ProBNP and N-terminal pro-B-type natriuretic peptide (NT-ProBNP) levels], a marker of myocardial dysfunction, in children with KD in acute and convalescent phases of disease. These levels were also estimated in febrile controls for comparison. The ProBNP (ProBNP and NT-ProBNP) levels were much higher in the acute phase of the KD patients compared to levels in the convalescent phase of KD (p = 0.000014). Similarly, the levels in the acute phase were higher when compared to the age- and sex-matched febrile controls (p = 0.000126). The receiver operating curve (ROC) analysis for the ProBNP levels in the acute phase of KD yielded an area under the curve of 0.954 ± 0.034 (p < 0.000, 95 % CI 0.886–1.0). Based on ROC analysis, a cutoff of 1025 pg/mL for ProBNP levels in the acute phase of KD had 88 % sensitivity and 96 % specificity for the diagnosis of KD. A lower cut-off of 514 pg/mL yielded a 100 % sensitivity and 80 % specificity for the diagnosis of KD. The ProBNP levels were higher in those with coronary artery abnormalities (CAA) compared to those without CAA in both acute (p = 0.013) and convalescent (p = 0.045) phases. ProBNP levels may be used as a surrogate marker for the differentiation of KD from other febrile, infectious illnesses and may also predict the involvement of coronary arteries.