Association of the HLA A2-B46-DR9 haplotype with autoimmune thyroid dysfunction after bone marrow transplantation in Chinese patients.

Autoimmune thyroid disease (AITD) may occur in patients after bone marrow transplantation (BMT). At a median follow-up of 4 years, among 194 allografts and 28 autografts, four patients (three allografts, one autograft) developed AITD. All carried the human leucocyte antigen (HLA) A2-B46-DR9 haplotype, strongly associated with AITD in the Chinese population. No significant thyroid disorder was detected in 190 patients without this haplotype. The frequency of AITD in BMT patients with the HLA A2-B46-DR9 haplotype was 12.5%, with a relative risk of 7.8 times that of non-carriers (P < 0.001). The risk of AITD should be recognized in recipients with high-risk HLA haplotypes, and regular screening might be warranted.