Neurochemical abnormalities in a patient with ataxia-telangiectasia.

We describe biochemical abnormalities found in autopsied brain of a patient with ataxia-telangiectasia. Neuropathologic changes were limited to the cerebellum and spinal cord. The atrophic cerebellum showed marked loss of Purkinje's and granule cells, and moderate loss of stellate and basket cells. Glutamic acid content was markedly reduced, and taurine content somewhat reduced in the cerebellar cortex, while gamma-aminobutyric acid (GABA) content was greatly reduced in the dentate nucleus. GABA receptor binding was reduced by 70% in cerebellar cortex. Phosphoethanolamine content was greatly reduced in the cerebellar cortex and inferior olivary nucleus. This compound was also deficient in 10 other brain regions and was the only extracerebellar neurochemical abnormality observed.