|
| |||||||||||||||||||||||||||||||||
Background LeschNyhan disease is a rare, devastating, X-linked recessive disorder of purine synthesis. Patients present with hyperuricemia, choreoathetosis, dystonia, and aggressive and self-injurious behavior. Although the genetic and biochemical abnormalities have been identified, the causes of the neuropsychiatric syndrome remain unclear.
Methods We used positron-emission tomography to measure presynaptic accumulation of fluorodopa F 18 tracer in the dopaminergic regions of the brains of 12 patients with LeschNyhan disease (age, 10 to 20 years) and 15 healthy controls (age, 12 to 23). The results were expressed as ratios of specific to nonspecific radioactive counts. A low ratio indicates decreased dopa decarboxylase activity and dopamine storage.
Results The fluorodopa F 18 ratio was significantly lower in the putamen (31 percent of control values), caudate nucleus (39 percent), frontal cortex (44 percent), and ventral tegmental complex (substantia nigra and ventral tegmentum; 57 percent) in the patients with LeschNyhan disease than in the controls. Uptake of the tracer was abnormally low even in the youngest patients tested, and there was no overlap in the values between patients and controls.
Conclusions Patients with LeschNyhan disease have abnormally few dopaminergic nerve terminals and cell bodies. The abnormality involves all dopaminergic pathways and is not restricted to the basal ganglia. These dopaminergic deficits are pervasive and appear to be developmental in origin, which suggests that they contribute to the characteristic neuropsychiatric manifestations of the disease.
Source Information
From the Laboratory of Cerebral Metabolism (M.E., A.J.Z., J.A.M., P.H.J., K.H., R.M.C.), and Laboratory of Psychology and Psychopathology (D.P.), National Institute of Mental Health, Bethesda, Md.; the Department of Anesthesiology, National Institutes of Health Clinical Center, Bethesda, Md. (J.G.H.); and the University of British Columbia, Vancouver, Canada (D.J.D.).
Address reprint requests to Dr. Ernst at the Laboratory of Cerebral Metabolism, Bldg. 36, Convent Dr., MSC 4030, Bethesda, MD 20892-4030.
This article has been cited by other articles:
HOME | SUBSCRIBE | SEARCH | CURRENT ISSUE | PAST ISSUES | COLLECTIONS | PRIVACY | TERMS OF USE | HELP | beta.nejm.org Comments and questions? Please contact us. The New England Journal of Medicine is owned, published, and copyrighted © 2009 Massachusetts Medical Society. All rights reserved. |