Citrullinemia is a urea cycle disorder which is an inherited metabolic disease, and stems from a deficiency of Argininosuccinic acid Synthetase. Argininosuccinate synthetase 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. It is suspected that the gene defect for Citrullinemia is an autosomal recessive genetic trait and is unknowingly passed down from generation to generation. This faulty gene only emerges when two carriers have children together and pass it to their offspring. For each pregnancy of two such carriers, there is a 25% chance that the child will be born with the disease and a 50% chance the child will be a carrier for the gene defect. Symptoms are hyperammonemia accompanied by lack of appetite, vomiting, listlessness, seizures, and coma. Onset is usually at birth, but symptoms may not be noticeable for days or weeks. When left untreated, brain damage, coma, and death will occur.
- Treatment may include a high-caloric, protein-restrictive diet, arginine supplementation, administration of sodium benzoate and sodium phenylacetate. Dialysis may be necessary in some affected individuals.