A 9-year-old boy with asymptomatic Wilson disease who developed neurologic symptoms after treatment with penicillamine is reported from the Department of Pediatrics, Universita Federico II, Naples, Italy. Initially referred for isolated hypertransaminasemia, and hepatomegaly was the only sign of Wilson disease. The diagnosis was confirmed with abnormal urinary copper excretion and high liver copper. After 10 weeks of treatment with penicillamine (20 mg/kg/day) and pyridoxine (25 mg/day), the child developed a tremor of the upper limbs which became progressively severe and incapacitating. Zinc sulfate (100 mg 3x daily) therapy and omission of penicillamine were followed by marked improvement within 2 weeks and remission of tremor at 4 month and 30-month follow-up. Serum transaminase and urinary copper levels were decreased following zinc treatment. 
COMMENT. Penicillamine therapy for Wilson disease may rarely precipitate the onset of neurologic symptoms. The authors cite only 5 previous cases, all adults. Zinc appears to be a satisfactory alternative treatment in a limited series. Other reported side-effects of penicillamine include fever, rash, adenopathy, pyridoxine-responsive optic neuritis, nephrotic syndrome, thrombocytopenia, and leukopenia.