Referral-spectrum Effect in Hypercupriuric Referrals for Suspected Wilson Disease: Diagnostic Implications for Ceruloplasmin and 24-hour Urinary Copper Excretion

In contemporary practice, elevated 24-hour urinary copper excretion (24-h UCE) often triggers referral for suspected Wilson disease (WD). In this hypercupriuric referral setting, interpretation of 24-h UCE may be distorted by spectrum effects. In this study, we aimed to compare conventional copper biomarkers in hypercupriuric referrals and evaluate whether a Leipzig-aligned ceruloplasmin (Cp) framework could provide a clinically useful triage approach.