Anticardiolipin antibodies in Japanese patients with multiple sclerosis.

We evaluated circulating anticardiolipin antibodies (aCL) in 38 Japanese patients who fulfilled the criteria of clinically definite multiple sclerosis (MS), using a newly developed EIA system with aCL-cofactor. Two of 38 patients (5.3%) had a aCL-cofactor-dependent positive serology, and differences compared with findings in controls were statistically significant. The 2 aCL-positive patients had similar clinical features with acute transverse myelopathy (ATM), optic neuropathy (OPN), normal cranial MRI and negative oligoclonal IgG bands (OCBs) in the cerebrospinal fluid (CSF). Among the 38 patients, 3 had ATM, OPN, normal cranial MRI and negative OCBs, hence, in a significant number of the patients (2/3; 67%) with these distinctive features, serology for aCL was positive. Therefore, they may have another condition associated with aCL, masquerading as MS. Serological testing for aCL with aCL-cofactor is recommended for the patients with clinical diagnosis of MS, especially for those showing OPN and ATM during the clinical course, and in Asian peoples where the incidence of ATM and OPN is relatively high among the patients with diagnosis of MS.