Juvenile Huntington's disease confirmed by genetic examination in twins.

Early-onset Huntington's disease (HD) occurs in approximately 10% of HD's cases. We report juvenile HD in phenotypically identical twins, evaluated by history, clinical and neurologic examination, minimental state examination, blood laboratory exams, cerebrospinal fluid examination, skull computed tomography, and genetic examination for HD. Patients had the akinetic-rigid variety (Westphal variant) of the disease and paternal inheritance. The laboratory workup confirmed the clinical diagnosis of HD, which adds this report to the rare cases of HD in twins reported in the literature.