[Antiphospholipid thrombosis syndrome and acquired activated protein C resistance]

To explore the correlation between antiphospholipid antibodies (APA) activated protein C resistance (APCR) and antiphospholipid thrombosis (APL-T) syndrome and investigate the mechanism of thrombosis in APL-T syndrome.

ELISA, APTT-LA and APTT+/-APC methods were used to detect anticardiolipin antibodies (ACA), lupus anticoagulants (LA) and APCR in 20 APL-T syndrome patients respectively.

Twenty patients were diagnosed as APL-T. The patients were classified in three ways. According to etiology, 14 of 100 systemic lupus erythematosus (SLE) patients were diagnosed as "secondary" APL-T, and 6 of 16 "unexplained" thrombosis and spontaneous abortion as "Primary" APL-T syndrome. According to antibodies, 12 of 20 patients with positive LA were diagnosed as lupus anticoagulant thrombosis syndrome (LA-T), 12 of 20 patients with positive ACA as anticardiolipin antibodies thrombosis syndrome (ACA-T). According to clinical presentation: 7 of 20 patients with deep vein thrombosis were classified as type I APL-T, 3 of 20 patients with cerebrovascular thrombosis as type II, 1 of 20 patients with vein cerebrovascular thrombosis and spontaneous abortion as type IV (mixing), and 9 of 20 patients with spontaneous abortion as type V (fetal wastage type). The ACAs and LA are strongly associated with APL-T. There is close relationship between APCR and APL-T.

The acquired APCR might be an important reason for thrombosis in APL-T caused by APA and LA.