Anti-Phospholipid Antibodies (APLA) are directed against phospholipids and phospholipid binding proteins. These can develop in a number of settings:
APS is not only based on labs; one also needs clinical features such as thrombosis or repeated miscarriage.
The two best characterized groups include anti-cardiolipid antibody (aCL) and lupus anticoagulant (LAC). LAC can interfere with PTT.