Gilles de la Tourette's syndrome. A postmortem neuropathological and immunohistochemical study.

Immunocytochemical studies of the human forebrain have shown that enkephalin-like, dynorphin-like and substance-P-like immunoreactivity (respectively ELI, DLI, and SPI) normally present in unique pattern (now termed woolly fibers) in the globus pallidus and substantia nigra, in which their concentration is at its densest. Quantitative determinations moreover indicate that the levels of all 3 peptides are higher in the globus pallidus and substantia nigra than in any other region of the brain. We report here the distribution of immunoreactivity of these 3 peptides in the brain of a patient showing the typical clinical manifestations of Gilles de la Tourette's syndrome (TS); a disease for which no characteristic or consistent neuropathological features have been discerned. In the case described here neuropathological examination by means of the usual histopathological methods showed no abnormalities to which the patient's illness could be ascribed. ELI- and SPLI-positive woolly fibers were densely stained and of normal distribution. DLI-staining was, however, considerably less dense throughout the brain than normal. The most striking finding was the total absence of DLI-positive woolly fibers in the dorsal part of the external segment of the globus pallidus; the ventral pallidum showed very faint staining. These observations, which indicate a decrease of dynorphin in striatal fibers projecting to the globus pallidus, are, to our knowledge, the first evidence of a distinct pathological change in the brain in TS.