Hyperammonemia due to N-acetylglutamate synthase deficiency

A rare disorder of urea cycle metabolism causing a deficit of ammonia detoxification and arginine synthesis, and characterized by hyperammonemia of variable severity. Manifestations range from neonatal presentation of poor feeding, vomiting, lethargy, tachypnea, convulsions and coma to adult-onset headaches, hazy gastrointestinal symptoms, seizures, behavioral/psychiatric problems, confusion and lethargy.