Infantile X-linked ataxia and deafness: a new clinicopathologic entity?

We describe an X-linked disorder of the CNS, characterized by onset, in infancy, of hypotonia, ataxia, sensorineural deafness, developmental delay, esotropias, and optic atrophy, and by a progressive course leading to death in childhood. Pathologically, neuron loss and gliosis of the dentate nucleus and inferior olive are conspicuous; involvement of the cerebellar cortex is less prominent. In the proband, the red nucleus, dorsal motor nucleus of the vagus, and central auditory pathways were severely affected. The mother of the proband, now 33, has self-limited episodes of ataxia, and cerebellar atrophy for which no other cause is apparent. The unique heredity, pathology, and clinical picture distinguish this entity from previously described inherited or metabolic ataxias.