[Therapy-refractory pelvic vein thrombosis in pregnancy as a sequela of protein S deficiency].

Protein S (PS) serves as a cofactor for activated Protein C, which has anticoagulative activity. PS deficiency (inherited or acquired) leads to spontaneous, recurrent thromboembolic complications in adulthood. PS level is significantly reduced during pregnancy and puerperium and during use of oral contraceptives. We report on our experience with a 26 year old pregnant woman, who developed a descending iliofemoral venous thrombosis in the 39th week of gestation. She underwent venous thrombectomy with a temporary arteriovenous fistula. Recurrent thrombosis occurred a few days after parturition. Redothrombectomy was performed successfully, but 2nd recurrent thrombosis occurred 10 days later. Further, lysis therapy did not reopen the venous system. Functional PS activity of 34% (IL-Instrumentation Laboratory Protein S-test, normal range 60-140%) was markedly reduced, which was the only pathological finding of coagulation analysis. For 20 years, the patient's mother has been undergoing coumarin therapy because of recurrent thromboembolic complications. We can therefore assume an inherited PS deficiency in the young mother.