For asymptomatic patients who have had effective chelation therapy and proven de-coppering, zinc salts are a useful follow-on therapy. Zinc’s proposed mechanism of action is induction of metallothionein in enterocytes, which promotes copper trapping and eventual excretion into the lumen. Importantly, treatment for Wilson disease is lifelong and monitoring of compliance is essential.8
Our 5-year-old patient was started on oral trientine at 20 mg/kg/d and a low copper diet. In response to this initial treatment, the patient’s liver function tests (LFTs) normalized, and he was switched to 25 mg tid of a zinc chelate, with continuation of the low copper diet. His LFTs have remained normal, although his urine copper levels are still elevated. He continues to be monitored periodically with LFTs and measurement of urine copper levels. He is also being treated for ADHD, as his presenting behavioral abnormalities suggestive of ADHD have not resolved.
THE TAKEAWAY
Although children presenting with symptoms consistent with ADHD often have ADHD, as was true in this case, it is important to consider other diagnoses. Unexplained elevations of liver function test values in children older than 1 year should prompt screening for Wilson disease.5,8 Additionally, other family members should be evaluated; if they have the disease, treatment should be started by age 2 years, even if the patient is asymptomatic.
In our patient’s case, routine screening saved the day. The complete metabolic panel revealed elevated ALT and AST levels, prompting further evaluation. Without this testing, his diagnosis likely would have been delayed, leading to progressive liver and central nervous system disease. With early identification and treatment, it is possible to stop the progression of Wilson disease.
CORRESPONDENCE
Jeffrey Taylor, MD, MS, Evangelical Community Hospital, Department of Pediatrics, 1 Hospital Drive, Lewisburg PA, 17837; jstaylor1@geisinger.edu.