Adult form of subactute necrotizing encephalomyelopathy.

Subacute necrotizing encephalomyelopathy (SNE) usually appears before the age of 2 years. Variability in its clinical presentation make antemortem diagnosis difficult. The morphologic diagnosis depends on the present of necrotizing lesions with a characteristic distribution within the CNS. We describe a patient with the uncommon adult form of SNE. The pathologic changes are those accepted as diagnostic of the more common infantile SNE, and permit a separation from Wernicke's encephalopathy. In the adult, the disease is thought to be due to a less severe thiamine-related metabolic defect than that of the infantile form. The infrequent clinical recognition in the adult form may be due in part to lack of medical awareness.