Late diagnosis of Kawasaki disease is associated with haptoglobin phenotype

Background Kawasaki disease (KD) is an acute febrile illness characterized by multiple clinical and biochemical features of inflammation and the most common complications of coronary artery abnormality (CAA). Haptoglobin (Hp) is an acute-phase protein whose phenotype is known to be involved in coron ary artery diseases. In this paper, we report the investigation of the asso ciation of Hp phenotype with the formation of CAA in KD. Patients and methods Forty-seven consecutive patients with clinically diagn osed KD were admitted. Sera were taken before therapy of intravenous immuno globulins (IVIG) plus aspirin, and levels of serum proteins were measured b y a rate immunonephelometer. The echocardiographic criteria for coronary ar tery abnormality were evaluated during acute or subacute stages. Hp phenoty ping was performed by Western immunoblotting. Results Duration of fever at diagnosis of KD was significantly different be tween patients with Hp 2-2 (6.4 +/- 1.2 days, n = 25) and with Hp(1) allele (Hp 2-1 plus Hp 1-1; 8.8 +/- 3.5 days, n = 22). In contrast, serum levels of Hp between KD patients with Hp2-2 and with Hp(1) allele (297 +/- 121 mg dL(-1) vs. 330 +/- 101 mg dL(-1), respectively) was not significantly diffe rent. On the other hand, no patients with Hp 2-2 (0/25) were recognized as having KD in subacute stage. However, 5 out of 20 patients with Hp 2-1 were recognized in subacute stage, and their incidence of CAA was 80.0% (4/5). Conclusions Patients with Hp 2-1 have patterns of delayed or incomplete pre sentation of clinical symptoms. Therefore, the late diagnosis of KD is asso ciated with haptoglobin phenotype.