The role of HLA-DR4 in the long-term prognosis of IgA nephropathy.

The study was performed to clarify the relationship between the long-term prognosis of IgA nephropathy and the HLA-DR4 antigen. From the 130 patients typed for HLA antigens, stable (n = 42) and progressive (n = 45) patient groups were selected. DR4 frequency was not different in the two groups (stable, 66.7 vs. progressive, 53.3%). However, the frequencies of HLA-DR4 and B35 in the 130 patients were significantly higher than those in the national control (DR4; 60.0 vs. 41.6%; B35:30.0 vs. 15.5%). We concluded that DR4 played no role in the long-term prognosis of IgA nephropathy, but that B35 and DR4 were associated with the disease in the Japanese population.