[Antiphospholipid antibodies in a series of 25 cases of lupus without antinuclear antibodies. Comparison with a series of 91 lupus patients with antinuclear antibodies].

Twenty-five patients with at least 3 of 1982 ARA criteria of SLE but without the ANA, were compared with 91 patients with 4 or more of the ARA criteria of lupus with positive ANA. The ANA-negative group was characterised by the low incidence of skin involvement, serous effusions and alopecia, and a relatively high incidence of thrombocytopaenia and venous and arterial thrombosis. Three types of antiphospholipid antibodies were looked for: the VDRL, antiprothrombinase and anticardiolipin antibodies by an immuno-enzymatic method. The VDRL was the only antibody which was significantly commoner in the ANA-negative group. Statistical studies showed that the three methods of demonstrating antiphospholipid antibodies detected crossed but not identical specificities. In the ANA-positive group only the antiprothrombinase was associated with a high incidence of venous thrombosis and stroke. In the ANA-negative group, only the anticardiolipin antibodies were associated with a high incidence of arterial or venous thrombosis. Two subgroups may be identified in the group of ANA-negative lupus patients: firstly, those with high anticardiolipin antibody titres with a high incidence of thrombotic and haematological complications, and, secondly, patients with low anticardiolipin antibody levels with a high incidence of cutaneous involvement, serous effusions and Raynaud's phenomenon.