Subacute Necrotizing Encephalopathy in Late Adolescence

Abstract

ARARE neuropathologic disorder, subacute necrotizing encephalomyelopathy, was first described in a young infant by Leigh¹ in 1951. Since then at least 48 additional cases have been reported.^2-27 Most cases have occurred in young infants and children, and parental consanguinity or other familial occurrence has been recorded in a number of families. Only seven cases have occurred in patients over the age of 10 years, with the oldest living 151/2 years. This report presents the case of a 17-year-old boy, the oldest patient with subacute necrotizing encephalopathy that we have found recorded. This young man escaped the usual short, morbid course seen in early childhood. He was mentally retarded for at least 12 years; his terminal decline of a few months was progressive and culminated with brain stem signs. This patient's course, particularly his long survival, and the neuropathologic findings are compared with those previously reported in necrotizing