Welcome to the NORD Physician Guide to the Urea Cycle Disorders. Information in this guide is provided by clinicians with expertise in these disorders who also serve as medical advisors to NORD and the National Urea Cycle Disorders Foundation. This information is provided in the hope that it will help patients obtain timely diagnosis and treatment.
The urea cycle disorders are hereditary metabolic disorders caused by a deficiency of one of the enzymes in the urea cycle responsible for removing ammonia from the bloodstream. Eight specific disorders are discussed in this guide.
The authors, NORD and NUCDF appreciate your interest in this topic. There are opportunities for follow-up questions and/or discussion in the Clinician Comments section of this guide.
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Disease Facts
Related Reports
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These disorders represent a substantial cause of brain damage and death among newborns and infants. Because they go undiagnosed in many cases, the exact incidence is unknown and underestimated. It is believed that up to 20% of cases of sudden infant death syndrome may be attributed to a hereditary metabolic disorder such as a urea cycle disorder.
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There are reports on the following related topics in NORD’s online Rare Disease Database for patients, families and the public at www.rarediseases.org:
Carbamoyl phosphate synthetase I deficiency > N-acetylglutamate synthetase (NAGS) deficiency > |

