Iron and Copper Liver Concentrations in Wilson Disease

Wilson disease (WD) results in the defective incorporation of copper into ceruloplasmin as well as decreased biliary copper excretion. Secondary iron overload has also been associated with WD; however, the prevalence is currently unknown. This study aims to determine the prevalence of potential secondary iron overload in patients suspected to have WD. The secondary aim was to determine whether common laboratory tests were associated with liver copper concentrations or the need for liver transplantation in a subset of patients with confirmed WD.

Using our institution's laboratory information system, 197 patients with liver copper concentrations > 250 mcg/g were identified who also had a concurrent liver iron concentration available. Correlations between copper, iron, and hepatic iron index were performed by log-transforming the data and then using the Pearson method. Furthermore, in a subpopulation of ten patients clinically confirmed to have WD, various laboratory test values were evaluated to determine associations with liver copper concentration or liver transplantation.

There was no significant association between copper and iron liver tissue concentrations (p=0.84). However, 13 (8%) patients aged 13 or older had a hepatic iron index >1.0 which may indicate secondary iron overload. Furthermore, in clinically confirmed WD patients, hemoglobin and hematocrit were inversely associated with liver copper concentrations (p=0.036).

Iron overload can be detected in liver tissues with elevated copper concentrations characteristic of WD Furthermore, in WD, low hemoglobin and hematocrit values were associated with elevated liver copper concentration. Clinicians should consider the possibility of secondary iron overload and/or anemia in patients with WD.