Wilson's disease (WD) is a genetic disorder characterized by an accumulation of copper in the body, mainly in the liver and brain. Patients suffering from this disease are monitored by liver function tests, blood copper levels, and 24-hour urinary copper determinations. Treatment is based either on chelating the copper accumulated in the body using D-penicillamine or Trientine or on limiting intestinal copper absorption with zinc salts. Monitoring copper elimination in urine collected over 24 hours is essential for estimating a patient's copper load, adapting treatment dosage, and detecting any copper deficiency. Nevertheless, urine collection is often complicated for patients, given the obvious constraints of collecting urine over 24 hours. Without this, clinical decisions are usually made based on spot urine. There is no official recommendation for monitoring urinary copper elimination other than on 24-hour urine. According to studies on healthy volunteers under physiological conditions, urinary copper elimination occurs according to a circadian rhythm, with minimal copper elimination between 8 pm and 4 am and maximum between 8 am and noon. The study would aim to find the period of the day best correlated with 24h urinary copper excretion