HLA-B27, arthritis and Yersinia enterocolitica infection.

Over a 3 1/2-yr period 25 cases of Yersinia enterocolitica arthritis were observed. This is a frequency of about 1% of the new patients seen at our Rheumatology Clinic. The histocompatibility antigen HLA-B27 was found in 14 of the 25 patients with Yersinia arthritis (56%). There was no difference in duration of disease, joint symptoms or laboratory data between the HLA-B27 positive or negative group. Six cases had a disease course longer than 1 yr. Four of them had a disease onset before the age of 16 yr and all cases had knee joint involvement. Our findings are discussed in relation to reports from other centers.