Antinucleosome antibodies may help predict development of systemic lupus erythematosus in patients with primary antiphospholipid syndrome

Patients with primary antiphospholipid syndrome ( PAPS) may evolve to systemic lupus erythematosus (SLE), even many years later. This makes differentiation between primary and secondary antiphospholipidsyndrome a difficult task. Studies in murine models of lupus have shown that the development of antinucleosome(anti-NCS) antibodies may occur from the early stages of life. We therefore hypothesize that anti-NCS antibodies could help predict development of SLE in patients with PAPS. We studied anti-NCS antibodies in 18 PAPS patients ( 15 female, three male), followed for a mean of 11 years to evaluate the potential development of SLE. When PAPS was diagnosed, nine patients were positive for anti-NCS antibodies. Six of them developed clinical manifestations of SLE. In contrast, none of the patients who were negative to anti-NCS antibodies developed it. These findings suggest that anti-NCS antibodies could help predict which patients with PAPS may eventually develop SLE.