[Antiprothrombinase type of circulating anticoagulants during acute disseminated lupus erythematosus].

We report the observations of 4 young women suffering from SLE witha circulatig antiprothrombinase anticoagulant. Antiprothrombinase is the most frequent circulating anticoagulant found in SLE (5 to 10 p. 100). SLE is the main aetiology for antiprothrombinase (over 50 p. 100). It is called 'lupus anticoagulant'. Some symptoms seem to be more frequent in SLE with antiprothrombinase. Such are biological signs (false positive tests for syphilis. Coombs test, thrombopenia, prothrombin deficiency) and clinical signs (venous or arterial thrombosis particularly if oestroprogestative treatment is taken, bleeding if thrombocytopenia or deficiency of prothrombin; repetitive abortion and may be neuropsychiatric signs). Antiprothrombinase is an autoantibody (IgG or IgG + M) polyclonal in SLE, with antiphospholipid activity. It could decrease the production of prostacyclin (PGI2) from free arachidonic acid derived from membrane bound phospholipids. Immunological properties of antiprothrombinase could account for clinical and biological associated signs.