Infantile neuroaxonal dystrophy. Ultrastructural study of peripheral nerve.

Ultrastructural study of the biopsied sural nerve in a case of infantile neuroaxonal dystrophy was made. The characteristic change in the ballooned axons is an accumulation of membranous profiles associated with mitochondria, glycogen like granules, dense bodies, vesicles and electron lucent material. The membranous profile is classified into three morphological types and discussed on each of them. Probably tubulomembranous profile of the first type is most common and may be cardinal deposit in this condition. These membranous structures of various types might be, however, only different manifestations occurring on the same morbid process. Enormous amount of glycogen like granules and mitochondria might be related to the metabolic derangement of carbohydrate in the ballooned axons. Electron lucent material we observed was not described in the previous papers on this condition. We added one more example showing that nerve biopsy is helpful to confirm the diagnosis in infantile neuroaxonal dystrophy.