Follow-up study of juvenile chronic polyarthritis with particular reference to histocompatibility antigen W. 27.

The HL-A antigen W.27 has been found in 88 to 96% of patients with ankylosing spondylitis (Brewerton, Caffrey, Hart, James, Nicholls, and Sturrock, 1973a; Caffrey and James, 1973; Schlosstein, Terasaki, Bluestone, and Pearson, 1973). More recently a high frequency of W.27 has been reported in Reiter's syndrome (Brewerton, Caffrey, Nicholls, Walters, Oates, and James, 1973c), acute anterior uveitis (Brewerton, Caffrey, Nicholls, Walters, and James, 1973b), and Yersinia arthritis (Aho, Ahvonen, Lassus, Sievers, and Tiilikainen, 1973). In a control Caucasian population, the frequency ofW.27 is 4 to 8% (Brewerton and others, 1973a; Schlosstein and others, 1973). The long-term follow-up of juvenile chronic polyarthritis has shown that a small proportion of patients presenting with peripheral arthritis may ultimately develop definite ankylosing spondylitis (Ansell, 1969; Chalmers, 1971), and others may show radiological sacroiliitis of ankylosing spondylitis type (Bywaters and Ansell, 1965). Family studies of patients with juvenile chronic polyarthritis have shown an increased incidence of ankylosing spondylitis in male relatives and of seronegative chronic polyarthritis in female relatives (Ansell, Bywaters, and Lawrence, 1962), and of sacroiliitis in male relatives aged 15 and over and in female relatives aged 45 and over (Ansell, Bywaters, and Lawrence, 1968). We decided to tissue type a small group of patients with juvenile chronic polyarthritis, who had been followed up for many years so that their pattern of disease had become established.