RESUMO
Markers of autoimmunity, such as autoantibodies, have been found in patients with endometriosis. These include the antinuclear antibodies (ANA). We aimed to evaluate the prevalence of ANA in a sample of patients with endometriosis and its possible clinical associations. Ninety-four patients with endometriosis and 91 controls were studied for ANA and extractable nuclear antigen (ENA; anti-Ro, anti-La, anti-Sm, and anti-RNP) profiles and anti-dsDNA. Epidemiological, clinical, and staging data in endometriosis were obtained. Patients with autoimmune disorders were excluded. Patients with endometriosis had a 21.2% prevalence of positive ANA vs. 5.4% in controls (P = 0.001). The ENA profile and anti-dsDNA were negative. Patients with positive ANA were more asymptomatic (P = 0.03) and had less dysmenorrhea. No associations with disease duration, patient age, or endometriosis stage were found. We found a high prevalence of positive ANA in patients with endometriosis. The presence of this autoantibody may be linked to a milder clinical expression of the disease.