Infantile Neuroaxonal Dystrophy

Neuropathological and biochemical studies were done of a 91/2-year-old girl with a sporadic form of infantile neuroaxonal dystrophy (INAD). The characteristic histopathological features were the following: (1) presence of eosinophilic spheroids in the central, peripheral, and autonomic nervous systems; (2) pallido-striato-nigral iron-containing pigmentary deposits; (3) cerebellar degeneration; and (4) associated neuronal, myelin, and glial changes. The biochemical analysis of the gray matter revealed a normal ganglioside level and composition, a reduction of glycoprotein-carbohydrate content with no alteration in the composition of the heteropolysaccharide chains of higher molecular weight, and a reduced level of glycosaminoglycans. The white matter chemical abnormalities consisted of a marked reduction in cerebrosides and minor abnormalities in the composition of gangliosides and dialyzable glycopeptides. Various views on the origin and possible pathomechanisms underlying the neuroaxonal dystrophy are entertained.