Serum exchangeable copper (EC) and relative exchangeable copper (REC) are blood tests developed to improve the assessment of copper levels in patients with Wilson's disease. EC measures the fraction of copper in the blood that is not bound to ceruloplasmin and reflects copper accumulation in the body. REC represents the proportion of this exchangeable copper relative to total serum copper. Previous studies have shown that EC and REC are more accurate than traditional copper tests for diagnosing Wilson's disease. This study aimed to evaluate the relationship between EC/REC and routine copper measurements in patients with Wilson's disease during follow-up, to assess their potential value in disease monitoring.