Human leukocyte antigen class II DQ alleles associated with Chlamydia trachomatis tubal infertility

Objective: To investigate epidemiologic tubal infertility risk factors and the relationship between HLA class II alleles and Chlamydia trachomatis tub al infertility. Methods: Forty-seven women with tubal infertility and 46 fertile controls w ere studied in Nairobi, Kenya. A questionnaire was administered and serum c ollected for measurement of C trachomatis antibodies. HLA class II molecula r typing was done with DNA extracted from peripheral blood lymphocytes. The prevalence of C trachomatis microimmunofluorescence antibody, chlamydia he at shock protein 60 antibody, and HLA class II alleles was compared among c ases of tubal infertility and fertile controls. Results: Women with tubal infertility more often had histories of pelvic in flammatory disease (15% versus 0%; odds ratio [OR] 16; 95% confidence inter val [CI] 5.5, 47) histories of spontaneous abortion (34% versus 7%; OR 6.7; 95% CI 2.8, 16), and antibodies to C trachomatis (53% versus 26%; OR 3.2; 95% CI 1.3, 7.7) than controls. Among infertile women, DQA*0101 and DQB*050 1 alleles were positively associated with C trachomatis tubal infertility ( OR 4.9; 95% CI 1.3, 18.6, and OR 6.8; 95% CI 1.6, 29.2, respectively). DQA* 0102 was negatively associated with C trachomatis tubal infertility (OR 0.2 ; 95% CI 0.005, 0.6). Conclusion: Chlamydia trachomatis infection is an important cause of tubal infertility in Nairobi. The association of specific HLA class II alleles wi th C trachomatis microimmunofluorescence seropositivity among women with tu bal infertility suggests that the DQ locus might modify susceptibility to a nd pathogenicity of C trachomatis infection. (Obstet Gynecol 2000;95:72-7. (C) 2000 by The American College of Obstetricians and Gynecologists.).