Lupus anticoagulants (LAs) and anticardiolipin antibodies (ACAs) are acquired circulating immunoglobulins that cross-react with anionic and neural phospholipids. These factors may display anticoagulant properties in vitro by interfering with phospholipid-dependent coagulation tests. These antibodies are usually not associated with a bleeding tendency. In fact, paradoxically to their name, since the initial recognition they have been related to systemic and cerebral thromboembolisms, despite their in vitro "anticoagulant" properties. We report the clinical and laboratory findings in 4 LAs and ACAs positive patients with brain ischemia.