Mondo Description Ornithine transcarbamylase deficiency (OTCD) is a disorder of urea cycle metabolism and ammonia detoxification characterized by either a severe, neonatal-onset disease found almost exclusively in males, or later-onset (partial) forms of the disease. Both present with episodes of hyperammonemia that can be fatal and which can lead to neurological complications.

Uniprot Description An X-linked disorder of the urea cycle which causes a form of hyperammonemia. Mutations with no residual enzyme activity are always expressed in hemizygote males by a very severe neonatal hyperammonemic coma that generally proves to be fatal. Heterozygous females are either asymptomatic or express orotic aciduria spontaneously or after protein intake. The disorder is treatable with supplemental dietary arginine and low protein diet. The arbitrary classification of patients into the 'neonatal' group (clinical hyperammonemia in the first few days of life) and 'late' onset (clinical presentation after the neonatal period) has been used to differentiate severe from mild forms.

Disease Ontology Description An urea cycle disorder that involves a mutated and ineffective form of the enzyme ornithine transcarbamylase.