Sneddon's Syndrome presenting with topographic disorientation.

A 32-year-old woman was admitted to our department for a progressive difficulty in topographic orientation, confirmed by an extensive battery of neuropsychological tests. All biochemical and immunological examinations of blood and cerebrospinal fluid and a cerebral MRI were normal, but a technetium-99m-ethyl cysteinate dimer-single photon emission CT (Tc-99m ECD-SPECT) scan showed bilateral parietal hypoperfusion. The patient refused to undergo other examinations, but 14 months later she returned to hospital for diffuse cutaneous livedo reticularis over her trunk and legs. This time the MRI showed small frontoparietal cortical-subcortical abnormalities suggestive of arterial ischemic infarctions. We made a diagnosis of Sneddon's Syndrome (SNS). SNS is characterized by the association of livedo reticularis and cerebrovascular disease; non-dermatological onset is extremely uncommon. To our knowledge, this is the first description of a patient presenting with cognitive impairment only and observed at such an early stage of the disease that a cerebral MRI was normal.