Association between endometriosis, infertility and autoimmune antiplatelet glycoprotein VI antibodies in two patients

Plain Language Summary What is the context? center dot Evidence for an immune system dysfunction is reported in endometriosis and the association between endometriosis and autoimmune diseases is well known. center dot No autoimmune platelet function defect has been described so far. What is new? center dot We report two unrelated patients with endometriosis-associated infertility presenting a platelet glycoprotein VI deficiency due to an autoantibody. center dot In both cases, a deficient platelet aggregation response to collagen, convulxin or CRP and a severe GPVI deficiency were observed. center dot Immunoblot revealed no indication of GPVI cleavage. What is the impact? center dot Our observation raises the question whether GPVI could be a preferential target for the development of anti-GPVI autoantibodies associated with endometriosis. center dot It does not seem that in these patients, GPVI deficiency is associated with an increased risk of severe bleeding disorder. The association between endometriosis and autoimmune diseases is well known, however no acquired platelet function defect has been described so far. We describe the case of two patients with endometriosis associated with an antiplatelet glycoprotein VI (anti-GPVI) antibody. The two women with deep pelvic endometriosis associated with secondary infertility presented a mild bleeding tendency, a deficient platelet aggregation response to collagen, convulxin or CRP and a severe GPVI deficiency. Immunoblot revealed a combined FcR gamma deficiency but no indication of GPVI cleavage. In the first case, platelet count was normal and an anti-GPVI IgG was detected in plasma. A first corticosteroids administration normalized in vitro platelet functions but further administrations were unsuccessful. Three IVF attempts failed. Conservative laparoscopic surgery was carried out after antifibrinolytic treatment without bleeding. The second case presented with a history of moderate thrombocytopenia and a weak anti-GPVI in the context of infertility and autoimmune disease, the Sjogren syndrome resolved after corticosteroids and hydroxychloroquine treatment. Acquired GPVI deficiencies are rare. It would be useful to determine whether the association with endometriosis is coincidental or not by more systematic investigations. It does not seem that in these patients, GPVI deficiency is associated with an increased risk of bleeding.