Abstract Although elevated anticardiolipin antibodies have been associated with idiopathic thromboembolic events, the disorder is not well understood. A case study of stroke in an otherwise healthy young adult spanning 6 years is presented. In this case, there was a correlation between increased serum concentrations of the antibodies, symptoms and periods of physiologic or emotional stress. Stress free intervals were accompanied by normal serum concentrations. The author proposes that anticardiolipin antibodies and their subtypes may be stress-induced markers and fluctuations in levels may correlate with periods of physiologic stress.