Can fibroblast growth factor (FGF)-23 circulating levels suggest coronary artery abnormalities in children with Kawasaki disease?

Kawasaki disease (KD) is an acute self-limited panvasculitis, primarily affecting young children, with an outstanding risk of cardiovascular complications. Fibroblast Growth Factor-23 (FGF23) is the latest member of the FGF family, acting on phosphate metabolism, which has been shown to display a potential role in the vascular remodelling. The aim of our study was to test the hypothesis that circulating serum levels of FGF23 might be related to the occurrence of coronary artery abnormalities (CAA) in children with KD.Serum of 109 consecutive KD patients (median age 30.5 months) were collected for the evaluation of intact FGF23 by ELISA test. Sixty sex/age-matched healthy children were studied as controls, after having excluded rheumatic, endocrinological and chronic renal diseases. In all these subjects a familiar predisposition to atherosclerosis was excluded.FGF23 levels resulted significantly higher in patients with KD than in controls (72±40 pg/ml vs. 12.3±3.2 pg/ml; p=0.01). Twenty-eight/109 KD patients having developed CAA (aneurysms or dilatations) presented significantly higher FGF23 levels than those without any coronary artery damage (120±40 pg/ml vs. 38.2±5 pg/ml; p<0.0001). Multiple logistic regression analysis showed that only serum FGF23 levels, among different general clinical and biochemical variables, were suggestive of coronary artery damage (OR=4.86).Based on this preliminary investigation, high serum FGF23 levels would seem suggestive of the potential occurrence of cardiac vascular complications in children with KD.