[Primary antiphospholipid syndrome: characteristics and course of a series of 17 cases]

Primary antiphospholipid syndrome (APS) is a thrombophilic disorder which is not associated with connective tissue diseases or with other diseases.

Retrospective review of patients diagnosed of primary APS in an Internal Medicine service between January 1996 and December 2000.

We identified 17 patients with primary APS. The most common presenting manifestations were deep vein thrombosis (7 cases) and ischemic stroke (3 cases). Eleven patients (65%) had vein thrombosis, 4 (24%) arterial thrombosis and no patient had both types of thrombosis. The 15 patients with thrombosis received treatment with indefinite oral anticoagulation (INR between 2.5 and 3.5). There was no recurrence of thrombosis or major hemorrhagic complications after a median follow-up time of 36 months (range 10-52 months).

The most common presenting manifestation of primary APS is deep vein thrombosis. Venous thrombosis is more frequent than arterial thrombosis. The occurrence of both types of thrombosis seems to be exceptional. Long-term oral anticoagulation is an effective and safe treatment to prevent the recurrence of thrombosis in patients with primary APS.