High regression rate of coronary aneurysms developed in patients with immune globulin-resistant Kawasaki disease treated with steroid pulse therapy.

Kawasaki disease is an acute vasculitis syndrome of unknown etiology that mainly affects small and medium-size arteries, particularly the coronary artery. Coronary artery lesions may develop into aneurismal formation and thrombotic occlusion, and progress to ischemic heart disease. The aim of the present study was to investigate the effect of steroid pulse therapy following intravenous immune globulin (IVIG) treatment on the regression rate of aneurysms in Kawasaki disease. Among 93 sequential patients referred to us, because of coronary artery lesions in the acute phase, we found 23 aneurysms in 12 patients during the period from January 1997 to January 2008. We divided them into two groups: a non-steroid group, 7 patients (13 aneurysms) treated with single or multiple IVIG but no steroid pulse therapy; and a steroid group, 5 patients (10 aneurysms) treated with multiple IVIG followed by steroid pulse therapy. We compared the regression rate of the aneurysms between the two groups, retrospectively. The regression rates of the aneurysms in the steroid group were significantly higher than those in the non-steroid group when we analyzed 1) all aneurysms (p = 0.007), 2) giant aneurysms (aneurismal diameter was 4 or more x normal, or > 8 mm) (p = 0.018), and 3) aneurysms in IVIG-resistant patients who were resistant to initial IVIG therapy (p = 0.035). All aneurysms, including the giant aneurysms in the steroid group, regressed, and the regression rate of the aneurysms in the non-steroid group was about 46%(6/13). Steroid pulse therapy may be beneficial for IVIG-resistant patients. Our data suggest that steroid pulse therapy may lead to regression of aneurysms.