Are infantile periarteritis nodosa with coronary artery involvement and fatal mucocutaneous lymph node syndrome the same? Comparison of 20 patients from North America with patients from Hawaii and Japan

We reviewed available clinical and pathologic autopsy material from 20 patients with infantile periarteritis nodosa with coronary artery involvement (IPN) from the continental United States, two Hawaiian patients with fatal mucocutaneous lymph node syndrome (MCLS; Kawasaki disease), and three patients with classical periarteritis nodosa (CPN). Comparison of the findings in patients with IPN and in patients with MCLS from Hawaii to material from patients with fatal MCLS from Japan showed no definite clinical reason to distinguish IPN from MCLS; neither gross nor microscopic features of the vascular lesions nor their pattern of distribution appears to warrant separation of IPN from fatal MCLS. CPN differs, both clinically and pathologically, from IPN/MCLS, and may well have a different etiology.