Interferon-gamma in the diagnosis and pathogenesis of pelvic inflammatory disease

Serologic markers were evaluated to determine if they could aid in the differential diagnosis of pelvic inflammatory disease in 48 consecutive women seeking evaluation for pelvic pain. On the basis of clinical and microbiologic parameters, 29 patients (60.4%) were diagnosed as having pelvic inflammatory disease. Neisseria gonorrhoeae only was isolated from the cervix of eight (27.6%) patients with pelvic inflammatory disease, five (17.2%) had only Chlamydia, and two (6.9%) had Neisseria and Chlamydia, whereas in 15 (48.3%) patients no pathogen was isolated. Interferon-gamma was present in significantly more sera (p less than 0.025) from patients with pelvic inflammatory disease (65.5%) than from women without pelvic inflammatory disease (15.8%). Sera from 10 healthy women lacked detectable interferon-gamma. In patients with only Neisseria, seven (87.5%) had circulating interferon-gamma; three (60%) of the women with only Chlamydia, one (50%) woman with Neisseria and Chlamydia, and eight (57.1%) with no identified pathogens were also positive for interferon-gamma. Sera from 11 of 28 patients with pelvic inflammatory disease (39%) but only one of 19 sera from women without pelvic inflammatory disease (5%) also inhibited the Candida-induced proliferation of control lymphocytes. This immunosuppressive activity was prevented by immunoprecipitation of interferon-gamma by anti-interferon-gamma antibody but not by treatment with anti-interferon-alpha antibody. The persistence of interferon-gamma in the sera of patients with pelvic inflammatory disease may aid in the differential diagnosis of this disease and increase our understanding of the pathogenesis of microbial-mediated tubal damage.