An unusual neurological disorder with abnormal copper metabolism.

Twin males aged 24 years showed dementia, dysarthria, gait disturbances and involuntary movements, with slightly low levels of serum copper and ceruloplasmin, and markedly low excretion of urinary copper. We propose that the unique combination of dementia, dysarthria, gait disturbances, involuntary movements and abnormalities of copper metabolism does not fit any known nosological entity and constitutes a "new" syndrome different from Wilson's and Menkes' diseases.