Cell-mediated immune response to chlamydia in anterior uveitis: role of HLA B27.

The relationship between HLA B27 anterior uveitis (AU) and evidence of chlamydia trachomatis infection was investigated in 35 consecutive patients attending a uveitis research clinic, using a complement fixation test and lymphocyte transformation test to chlamydia (ornithosis-psittacosis) group antigen. A significant stimulation index (SI greater than 2) was found in 73% (11/15) of the HLA B27 positive patients compared with the HLA B27 negative AU patients and controls (P less than 0.03). There was no difference between AU patients with and without associated rheumatic disease or in terms of antibody response. The results of the present study indicate a significant relationship between the cell-mediated immune response to chlamydia group antigen and the HLA B27 positive subgroup of patients with AU.