Disorders of urea cycle: case report

Main Article Content

Adolfo Álvarez
Carlos Gallón
Ornella Ruíz


hyperammonemia, seizure, urea


Background: Disorders of urea cycle constitute approximately 50% of severe neonatal hyperammonemia. These disorders are consequence of the deficiency of some of the enzymes involved in the cycle. The prognosis will depend on the degree of enzymatic deficiency, as well as on the timely diagnostic approach and the early treatment.

Case report: A neonate with neonatal crisis of difficult management associated to hyperammonemia, which allowed to suspect an inborn error of the metabolism, specifically urea cycle disorder. Timely treatment was initiated, with symptoms control and favorable clinical course.

Discussion: Urea cycle disorders are part of innate errors in ammonia detoxification or arginine synthesis, secondary to defects in the enzymes involved in this cycle. Clinical manifestations are secondary to elevated levels of serum ammonia. The treatment is composed of an acute and chronic phase.

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