Antiphospholipid-negative Sneddon's syndrome: A comprehensive overview of a rare entity

The term Sneddon's syndrome (SS) has been used since 1965 to describe a vasculopathy characterized by a combination of cerebrovascular disease with livedo racemosa. SS may be classified as antiphospholipid+ (aPL+) or antiphospholipid− (aPL−). Little is known about aPL− SS; in this review we describe the epidemiology and pathogenesis of aPL− SS, as well as the clinical and histologic features. We discuss recent findings in terms of neurologic and cardiac involvement. Moreover, differential diagnoses of conditions that may present with both livedo racemosa and stroke are discussed. Finally, we discuss real-life practical issues such as the initial investigations to be performed, long-term follow-up, and therapeutic management of aPL− SS patients.