Condition: Argininosuccinic Aciduria

Argininosuccinic aciduria is a rare inherited disorder characterized by deficiency or lack of the enzyme argininosuccinate lyase (ASL). Argininosuccinate lyase is one of six enzymes that play a role in the breakdown and removal of nitrogen from the body, a process known as the urea cycle. The lack of this enzyme results in excessive accumulation of nitrogen, in the form of ammonia (hyperammonemia), in the blood. Affected infants may experience vomiting, refusal to eat, progressive lethargy, and coma. Argininosuccinic aciduria is inherited as an autosomal recessive trait.

The urea cycle disorders are a group of rare disorders affecting the urea cycle, a series of biochemical processes in which nitrogen is converted into urea and removed from the body through the urine. Nitrogen is a waste product of protein metabolism. Failure to break down nitrogen results in the abnormal accumulation of nitrogen, in the form of ammonia, in the blood.