[HL-A W27 antigen and atypical rheumatic pelvispondylitis]

The authors report 26 cases of atypical inflammatory rheumatism in which the discovery of HL-A W27 antigen indicated the possibility of atypical ankylosing spondylarthritis. These patients included 17 men and 9 women with an average age of 35.6 years. The clinical symptoms included :--pelvic or vetebral signs alone in 8 cases,--pelvic or vertebral signs combined with peripheral inflammatory rheumatism, the latter being always cleaarly evident, in 9 cases,--extravertebral signs alone without any involvement of the vertebral column or of the sacroiliac joints in 9 cases (8 cases of peripheral inflammatory rheumatism, 1 case of talalgia). The vertebral radiograms were normal in 84 percent of cases. The sacroiliac joints were clear radiologically in 65 percent of cases. In the other cases the lesions, generally unilateral, were extremely discrete. In all the cases, the Waaler-Rose reaction was negative. The therapeutic test with non-hormonal anti inflammatory products were generally positive. The evolution of the condition confirmed the diagnosis of rheumatic pelvispondylitis in 2 cases. The patients have been under observation for insufficient time to be sure whether all the cases presented represent authentic cases of ankylosing spondylarthritis that were at first atypical. The authors emphasize the high percentage of female cases (38 percent) the high frequency of extra-vertebral manifestations. They also emphasize the value of looking for HL-A W27 antigen in patients with atypical inflammatory rheumatism.