Benign hereditary chorea. A case report

Benign hereditary chorea--entity or syndrome?

The existence of "benign hereditary chorea" (BHC), a rare disorder of childhood-onset familial chorea without other neurologic features or progression, has increasingly been questioned, because many patients with this disorder were subsequently diagnosed with different conditions. We therefore analyzed all published reports of families with BHC and contacted their authors to obtain follow-up information. In addition, we reviewed all patients in whom at least one of the authors had at some stage considered a possible diagnosis of BHC. Of 42 families reported to have BHC in the literature, we obtained follow-up information on 11 families, three of which had been seen by us. An additional seven new, unreported families and four sporadic cases, in which this diagnosis was suspected by at least one of us at one point, were reviewed and videotaped. On reviewing the videotapes of the 11 families in the literature, the diagnosis of BHC was changed in nine. In the remaining two families, atypical features suggesting different diagnoses were present in the original reports. In none of our own previously unreported patients (seven familial and four sporadic) was BHC diagnosed unequivocally by all evaluators after review of their video recordings. In three of these families and all four sporadic patients the diagnosis was changed; in one family multifocal myoclonus could not be differentiated from chorea by any author, and in the remaining three families no consensus between the raters was found. Apart from the 11 families in whom we obtained follow-up information, analysis of the remaining 31 reports on families with BHC also revealed atypical features in the majority. We conclude that BHC is not a diagnosis, but a syndrome that requires further investigation. Whether there is a distinct entity "BHC" with a single gene abnormality remains to be proven.

Ataxia without telangiectasia masquerading as benign hereditary chorea

We report a nonconsanguineous family in whom two (of three) sons developed isolated chorea in early childhood, suggesting a diagnosis of benign hereditary chorea (BHC). However, cerebellar ataxia and oculomotor apraxia, without telangiectasia, subsequently developed. Chromosome analysis showed increased radiosensitivity in both brothers and translocations in the younger one. We conclude that ataxia with chromosomal instability may masquerade as BHC in some patients.

Exclusion mapping of the benign hereditary chorea gene from the Huntington's disease locus: report of a family

A Greek family is presented in which seven members suffered from benign hereditary chorea (a rare autosomal dominant non-progressive chorea without dementia). All patients and three informative healthy relatives were submitted to DNA analysis using probes from loci linked to Huntington's disease. The results confirm one previous suggestion that these two disorders are not allelic and that they should be considered as two distinct genetic entities.

Benign hereditary chorea

Benign hereditary chorea is an uncommon inherited form of childhood chorea that can be mistaken for much more serious disorders, such as Huntington disease. The clinical manifestations of this condition are reviewed, emphasizing the differential diagnosis, treatment modalities, and evaluation of childhood chorea.