Abstract
A clinical and immunogenetic study was performed on a three-generation family with Reiter's disease (RD). Twelve of 56 members of the family (33 clinically examined) including one in-law, had symptoms of arthritis, urethritis, conjunctivitis, uveitis, and/or mucocutaneous manifestations, but only one had the complete triad of Reiter's syndrome (RS). Radiographic sacro-iliitis was found in 7 individuals, and monoarticular onset was reported in 5 out of 7 with peripheral arthritis. HLA B27 was found in 26 of the 37 family members who were tissue typed (including one in-law). All individuals with RD were B27-positive. Seven different B27 phenotypes were identified. This finding suggests that RD is associated with the B27 antigen itself, and not to a gene closely linked to B27. From a pedigree analysis of this family an autosomal dominant inheritance with incomplete penetrance or multifactorial inheritance seemed the most probable alternatives. The family history is a useful adjunct in the diagnosis of RD.