ANALYSIS OF HLA ANTIGENS IN PATIENTS WITH DIFFUSE PANBRONCHIOLITIS

A new clinicopathologic entity, diffuse panbronchiolitis, was recently reported in Japan. The disorder is characterized by recurrent sinopulmonary infection and respiratory bronchiolitis. We identified cases of familial diffuse panbronchiolitis and found that many siblings of the patients had paranasal sinusitis. Because of this, we performed HLA analysis of the patients with diffuse panbronchiolitis. In HLA Class I and Class II antigens, Bw54 significantly increased (frequently: 63.2%; RR = 13.30; corrected p value <1.08 x 10-10), whereas Cw1 and MC1 (a new HLA-DR-related antigen) slightly increased. These increases might be explained by the fact that these two antigens, Cw1 and MC1, formed a haplotype with Bw54, which suggests that one or some of the genes controlling the susceptibility and/or immune responsiveness of diffuse panbronchiolitis might be located near HLA loci. In addition, Bw54, or its related haplotype, exists only in Japanese, Chinese, and Korean populations. This may explain why a similar disease had not been reported in the English literature.