Family studies in Bechterew's syndrome (ankylosing spondylitis). II. Prevalences of symptoms and signs in relatives of HLAB27 negative probands.

All available adult first-degree relatives of 9 probands with HLAB27 negative ankylosing spondylitis were examined. Completion rate was 90%. Prevalences of symptoms and signs and distributions of chest and spinal mobility are presented. No secondary case of Bechterew's syndrome was found among the relatives, compared with 10% among the relatives of HLAB27 positive probands (p = 0.05). We conclude from this study and that of relatives of HLAB27 positive probands, that a HLAB27 negative relative runs a low risk of contracting Bechterew's syndrome, irrespective of the HLAB27 status of the proband.