Neuropathologic changes in ataxia-telangiectasia.

The neuropathologic findings in a 17-year-old boy with ataxia-telangiectasia are described. In agreement with previous reports, pathologic changes were present in the cerebellum, spinal cord, dorsal root ganglia, and straited muscle. The lesions in the spinal cord and dorsal root ganglia were more severe than previously described. Abnormalities were also seen in several brain stem nuclei, including the mesencephalic nucleus of the trigeminus and the substantia nigra. In addition, a small hamartomatous tumor was found in that thalamus.