Co-twin control study on cerebral manifestations of systemic lupus erythematosus.

All available twin pairs systemic lupus erythematosus (SLE) derived from the Finnish Twin Cohort were studied by clinical evaluation, magnetic resonance imaging (MRI), anticardiolipin (aCL), and antineurofilament (ANFA) antibodies. One of the five monozygotic and one of the eight dizygotic pairs were concordant for SLE. 10 of the 15 patients showed clinical neurological abnormalities, and 11 had abnormal MRI of the brain. Altogether, 12 patients were considered to have neuropsychiatric lupus (NPSLE). Seven of the 11 patients with long-term corticosteroid treatment had either central or cortical atrophy. High or moderate aCL level was found in eight patients and two co-twins. Of them, six patients had at least two manifestations of the antiphospholipid syndrome. ANFAs were found in five patients and four co-twins. Five co-twins fulfilled some of the SLE criteria. Of them, three MZ twins and one additional DZ co-twin with no ARA criteria had findings suggesting central nervous system (CNS) involvement. The results indicate that the majority of SLE patients has cerebral abnormalities either as a result of SLE, or concomitant risk factors. The co-twins without clinical SLE often have minor signs of SLE, and even they may have neurological and MRI abnormalities. However, their aCL and ANFA levels seem not to correlate with MRI abnormalities.