Antiphospholipid Syndrome: Expanding the Spectrum of Autoimmune Thrombosis
The antiphospholipid syndrome (APS) is an acquired prothrombotic syndrome characterized by venous or arterial thromboses and pregnancy morbidity. It can present as primary APS without any discernable underlying disease, or in association with systemic autoimmune disease [usually systemic lupus erythematosus (SLE)], infections (mainly chronic viral infections) and malignant process, among others. It may also occur rapidly over days or weeks, when it is known as catastrophic APS (CAPS).
The first study described one of the largest known cohorts of patients with primary APS from 4 different referral centers. The final study sample included 128 patients with primary APS with a median age of 42 years and mean follow-up of 9 years. After a median disease duration of 8.2 years, 110 (86%) patients remained with primary APS; 11 (8%) patients developed SLE; 6 (5%), LLD; and 1 (1%), myasthenia gravis. At the end of the study, 113 (88%) patients were alive and 15 (12%) patients had died. Our study confirms that progression from primary APS to SLE or LLD is unusual, even after a long follow-up.
In the second study, we evaluated 120 cases of antiphospholipid antibodies associated with malignancies with a mean age of 56 years, The main hematological malignancies found were B-cell lymphoma, spleen lymphoma and chronic myeloid leukemia. The main solid tumors were renal cell carcinoma, primary tumor of unknown origin, lung adenocarcinoma and breast carcinoma. Around one third of patients achieved aPL remission after treatment.
In the third study, we analyzed 15 cases of CAPS that appeared during pregnancy or the puerperium with a mean age at the time of the CAPS event of 27 years. In 7 of the 14 (50%) cases, CAPS appeared during pregnancy, in 6 (43%) cases it presented during puerperium and in 1 (7%) after curettage for a fetal death. The main clinical and serological characteristics were similar to those of patients with CAPS triggered by other factors, however we found some particular features including placental infarctions, pelvic vein thrombosis and myometrial thrombotic microangiopathy and HELLP syndrome.
Final conclusion: Primary APS is a widely recognized distinct entity which rarely progresses to SLE, even after long-term follow-up. APS may also be associated with other chronic disorders, such as solid tumors or hematological malignancies. In cases with the life-threatening variant of APS known as CAPS, pregnancy and the puerperium are periods of high susceptibility for the development of this often fatal form of presentation.
Advisor:Cervera, Ricard; Khamashta, Munther A.
School:Universitat de Barcelona
Source Type:Master's Thesis
Date of Publication:10/03/2007