1985 Volume 17 Issue 6 Pages 571-576
We report a 16-year-old boy with Wilson disease who relapsed suddenly with generalized dystonia, which was improved by a high dosage of trihexyphenidyl. He was diagnosed as having Wilson disease when he developed a hemolytic crisis at age 6. When he was 14, gait disturbance, dysgraphia and dysarthria appeared. These were improved by an increase in D-penicillamine dosage only. He was well until he deteriorated acutely soon after suffering acute respiratory infection.
On admission, he could neither walk, speak nor swallow, and showed violent involuntary movement and right hemiplegia. Hepatic functions, however, were normal. Dystonia and anarthria were persistent, although involuntary movement and hemiplegia gradually improved. Surface EMG showed the characteristic dystonic pattern.
A few weeks after treatment with trihexyphenidyl at 10 mg daily was started, he became able to stand, walk and write. When the medication was discontinued to ascertain its effects, he became obviously worse and could hardly walk or write. Psychiatric symptoms including irritability and emotional instability were noticed as adverse effects, but they were not severe enough to stop the medication. Seven months after treatment began, the dystonia tended to fluctuate, increasing in the morning and decreasing in the evening, with no corresponding diurnal changes in homovanillic acid and dopamine levels in the CSF.
Fahn (1979) reported that the treatment of dystonia of various types with a high dosage of trihexyphenidyl was especially effective in childhood. In the present case, we too experienced a beneficial effect with trihexyphenidyl at the dosage of 10-12 mg daily without any severe adverse effects.
