Discriminating chorea-acanthocytosis from Huntington's disease with single-case voxel-based morphometry analysis.

BACKGROUND AND PURPOSE: Chorea-acanthocytosis is clinically difficult to distinguish from Huntington's disease because these disorders have similar symptoms and MR imaging findings. We evaluated the usefulness of single-case voxel-based morphometry (VBM) analysis for differentiating the two diseases as well as VBM analysis. MATERIALS AND METHODS: We examined five genetically proven chorea-acanthocytosis patients and 11 Huntington's disease patients to detect differences in the gray and white matter atrophic pattern by using single-case VBM analysis in each patient and their clinical findings. We also evaluated VBM analysis for a group comparison in both disease and control groups. RESULTS: The single-case VBM analysis results demonstrated a gray matter volume loss in caudate nucleus in all 16 patients. A characteristic symmetrical white matter volume loss was detected in globus pallidus, putamen, and thalamus on both sides in all the chorea-acanthocytosis patients, but this pattern of atrophy was not seen in any of the Huntington's disease patients. With the VBM analysis, a significant gray matter volume loss was noted in caudate nucleus on both sides in chorea-acanthocytosis patients compared with Huntington's disease patients, and a more extensive white matter volume loss around the basal ganglia and thalamus was observed in chorea-acanthocytosis patients compared to Huntington's disease patients, consistent with the single-case VBM analysis results. Genetic testing identified two novel pathogenic mutations, exon 1 c.16_22delGTGGTCG and exon 55 c.7736-7739delGAGA in a chorea-acanthocytosis patient. CONCLUSIONS: Single-case VBM analysis may be useful to differentiate chorea-acanthocytosis from Huntington's disease with a focus on white matter atrophy.

Use of electroconvulsive therapy in a patient with chorea neuroacanthocytosis and prominent delusions.

A middle-aged white man with a diagnosis of chorea neuroacanthocytosis developed progressive and distressing persecutory delusions with an obsessional component. Pharmacotherapy was ineffective in controlling the symptoms or halting their progression. Electroconvulsive therapy was attempted with very limited success but had to be discontinued owing to mild elation and increased irritability. The patient's distress was only improved after his transfer to a nursing home specializing in Huntington disease.

The neuropsychiatry of neuroacanthocytosis syndromes.

The neuroacanthocytoses are a group of disorders characterised by peripheral blood acanthocytes, central nervous system as well as neuromuscular symptoms. These disorders uniformly result in pathology in the basal ganglia, which account for the characteristic motor symptoms such as chorea or dystonia, but may also account for the apparent elevated rates of major mental disorders in these syndromes. Elevated rates of dysexecutive syndromes, obsessive-compulsive disorder, depression and schizophrenia-like psychosis appear to occur in chorea-acanthocytosis, McLeod's syndrome, pantothenate kinase-associated neurodegeneration, and Huntington's disease-like 2. Disruptions to key frontostriatal loops secondary to pathology in the striatum and pallidum appear to predispose individuals to major neuropsychiatric syndromes; however, treatment can be instituted for a number of these manifestations, which lessens the overall burden of disease in neuroacanthocytosis patients and their families.

Onset of neuropsychiatric symptoms after psychological trauma may result in erroneous diagnostic bias.

We report a case of neuroacanthocytosis, which was misdiagnosed as conversion disorder. Because the onset was after a psychologically stressful physical trauma, the patient's symptoms were interpreted in terms of psychological regression. The case clearly points out the defects of descriptive psychiatric diagnosis, especially in the area of somatoformal disorders. It also reminds the clinicians to keep in mind rare neurological disorders as possible causes for psychiatric symptoms.