Longitudinal Study of Urea Cycle Disorders

This study tracks the long-term health and outcomes of people with urea cycle disorders (UCDs) — a group of rare inherited conditions where the body cannot properly remove ammonia from the blood, causing toxic buildup that can damage the brain. The study covers several specific enzyme deficiencies including OTC deficiency, CPS I deficiency, citrullinemia, argininosuccinic aciduria, and others. You may be eligible if: - You have a confirmed or highly suspected diagnosis of a urea cycle disorder (NAGS, CPS I, OTC, AS, AL, ARG, HHH syndrome, or CITR deficiency), based on enzyme testing, genetic testing, or elevated ammonia with a first-degree relative meeting diagnostic criteria You may NOT be eligible if: - Your hyperammonemia (high ammonia) is caused by something other than a UCD, such as an organic acidemia, mitochondrial disorder, lysinuric protein intolerance, or primary liver disease - You have a rare unrelated condition such as Down's syndrome, extreme prematurity, or intraventricular hemorrhage Talk to your doctor to see if this trial is right for you.