Neurological complications due to copper deficiency in the context of Wilson disease treatment: a case report with long-term follow-up and review of the literature

The objective is to investigate the presentation, complications, management, and outcomes of copper deficiency-induced neurological pathologies due to Wilson disease (WD) overtreatment. We examined the case of a WD patient who developed a low thoracic dorsal myelopathy due to chronic hypocupremia from excessive zinc therapy. A comprehensive literature review was conducted to identify similar cases. Ten additional cases of neurological pathology resulting from copper deficiency in the context of WD over-treatment were identified, all occurring during therapy with zinc salts. Myelopathy and peripheral neuropathy were the most common complications, while two additional groups reported leukoencephalopathy. Early cytopenia was often associated with copper deficiency-related neurological pathology appearing early in the context of copper deficiency. WD patients undergoing treatment, especially with zinc salts, should be closely monitored to prevent over-treatment and the consequent copper deficiency. Regular complete blood counts could provide early detection of copper deficiency, avoiding irreversible neurological damage. Swift recognition of new neurological signs not consistent with WD and timely discontinuation of the decoppering therapy are critical for improving outcomes. The optimal management, including the potential benefit of copper supplementation in patients with WD and subsequent therapy adjustments, remains unclear and necessitates further investigation. Despite the general poor functional neurological outcomes, there were some exceptions that warrant further exploration.