Urea Cycle Disorders: Group of rare disorders characterized
by accumulation of hyperammonemia and clinically presenting with a lack of
appetite, vomiting, drowsiness, seizures, and/or coma. Other features
include hepatomegaly and cerebral dysfunction caused by the urea level.
Life-threatening complications may result. In addition to OTCD, carbamyl
phosphate synthetase (CPS) deficiency, citrullinemia (argininosuccinate
synthetase deficiency), argininosuccinate lyase deficiency, argininemia, and
N-acetylglutamate synthetase (NAGS) deficiency must be considered in
individuals affected with these symptoms.