Increased Plasma Adrenomedulin Levels in Kawasaki Disease with Coronary Artery Involvement

Abstract

Adrenomedullin (AM) is a potent vasodilating and natriuretic peptide originally isolated from human pheochromocytoma. The main source of circulating adrenomedullin is now thought to be the vasculature. Kawasaki disease (KD) is an acute febrile illness in young children, characterized by systemic vasculitis preferentially affecting coronary arteries. We hypothesized that plasma AM levels are increased reflecting coronary artery vasculitis in KD. To elucidate this hypothesis, we measured plasma AM levels by radioimmunoassay in six patients with Kawasaki disease (5 male, 1 female, 0.4-2.6 years, 1.3±0.8 years) at before and 3days after high dose intravenous immune globulin therapy and at recovery phase (2 weeks later). In all patients, white blood cell count (WBC) and serum C-reactive protein (CRP) levels increased before treatment (WBC 16500±4509/ul, CRP 11.1±4.1). Compared with normal subjects (9.5±0.5 fmol/ml), plasma AM levels were markedly elevated before treatment. Highest levels of each patients were ranged 58.2 to 141.9 fmol/ml (90.5±35.4 fmol/ml).Specifically, plasma AM levels were remarkably higher in 2 patients who had been detected the coronary artery dilatation by echocardiography (125.6 and 14.9 fmol/ml, each). We believe that the rise in plasma AM in KD is due to the cytokine induced increase of AM expression in vasculature, especially in the coronary artery. Marked elevation of plasma AM at acute phase of KD may help to diagnose the coronary artery involvement in KD.