Antiphospholipid antibodies: a disease marker in 25 patients with antinuclear antibody negative systemic lupus erythematosus (SLE). Comparison with a group of 91 patients with antinuclear antibody positive SLE.

Twenty-five antinuclear antibody (ANA) negative patients with systemic lupus erythematosus (SLE) or lupus-like disease were compared to 91 ANA positive patients with SLE for clinical and biological symptoms. Cutaneous symptoms were infrequent in ANA negative patients (p less than 0.03). Thrombocytopenia (p less than 0.001), venous or arterial thrombosis (p less than 0.02) as well as cerebral infarction (p less than 0.001) were more frequent. Three types of antiphospholipid antibodies were determined by different methods; the VDRL, the lupus anticoagulant and an ELISA for IgG anticardiolipin antibody (aCL). The frequency of a positive VDRL test was significantly higher in the ANA negative group (p less than 0.05). Correlation studies suggest that the 3 methods are not redundant and detect overlapping but not identical antibodies. Of the 3 antiphospholipid antibody assays, only the IgG aCL test was significantly associated with thrombosis in the ANA negative group (p less than 0.02).

[Antiphospholipid antibodies in a series of 25 cases of lupus without antinuclear antibodies. Comparison with a series of 91 lupus patients with antinuclear antibodies]. / Etude des anticorps antiphospholipides dans une série de 25 maladies lupiques sans anticorps antinucléaires. Comparaison avec une série de 91 lupus avec anticorps antinucléaires.

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.