Forty-four patients with typical palindromic rheumatism were typed for HLA-A,B,C and DR antigens. The mean duration of follow-up of our patients was 4.0 yrs. (range 1-12 yrs.). During this time 27% of patients showed a seropositivity; 22% of patients developed polyarthritis, 1 patient revealed a Sjögren syndrome and 3 patients showed a spontaneous improvement. The HLA-B16 antigen was increased in patients compared with controls, but the difference was not statistically significant. A, C and other B antigens were found with normal frequencies. The HLA-DR antigens did not reveal any differences between patients' and controls' values, either 40% of patients who developed RA carried the HLA DR4 antigen.