HLA antigens in patients with interferon-alpha-induced autoimmune thyroid disorders in chronic hepatitis C

Background/Aims: To determine the immunological predisposition to autoimmun e thyroid disorders induced by interferon-alpha therapy, human leukocyte an tigen (HLA) was analyzed in patients with chronic hepatitis C who developed autoimmune thyroid disorders during or after treatment with interferon-alp ha. Methods: Four hundred and thirty-nine patients with chronic hepatitis C (27 8 males and 161 females, aged 20-73 years) were treated with interferon-alp ha (natural-alpha, 169; alpha-2a, 82; alpha-2b, 188) for 24 weeks. Results: Seventeen of 439 (3.9%) patients developed symptomatic autoimmune thyroid disorders; these included nine cases of hyperthyroidism and eight c ases of hypothyroidism, The incidence of HLA-A2, B46 and Cw7 increased in p atients with interferon-alpha-induced autoimmune thyroid disorders. Especia lly, the incidence of HLA-A2 (15/17; 88.2%) was significantly higher than t hat observed in the general population in Japan (corrected p-value (p(c)): p(c)<0,003), The odds ratios for the relative risk of the autoimmune thyroi d disorders were A2, 10.6 [95% confidence interval, 2.4-46.5]; B46, 4.8 [1. 6-14.0]; and Cw7, 3.0 [1,1-7,91, Conclusions: Our study revealed that HLA-AZ is highly linked to the autoimm une thyroid disorders induced by interferon-alpha-therapy in patients with chronic hepatitis C.