Anticardiolipin antibodies are not a useful screening tool in a nonselected large group of patients with multiple sclerosis.

Recent works claiming that primary antiphospholipid syndrome (PAPS) cannot be clinically distinguished from multiple sclerosis (MS) recommend that MS patients be screened for anticardiolipin antibodies (ACA). In this study 296 randomly selected patients with MS and clinically isolated syndromes and 51 healthy controls were analyzed; ACA, anti-beta2-glycoprotein I, or antiprothrombin was found in 6 patients. No predominance of any kind of clinical manifestations and no cardinal manifestations of PAPS were found in these patients. ACA tests should be performed only when a suspicion of PAPS is raised and atypical clinical presentation for MS is found.