E72.4

Applicable To

• Hyperammonemia-Hyperornithinemia-Homocitrullinemia syndrome

• Ornithinemia types I, II)

• Ornithine transcarbamylase deficiency

Approximate Synonyms

• Deficiency, ornithine transcarbamylase

• Disorder of ornithine metabolism

• Hyperornithinemia hyperammonemia homocitrullinemia

• Hyperornithinemia-hyperammonemia-homocitrullinuria syndrome

• Ornithine carbamoyltransferase deficiency

• Ornithine metabolism disorder

Clinical Information

• An inherited urea cycle disorder associated with deficiency of the enzyme ornithine carbamoyltransferase, transmitted as an x-linked trait and featuring elevations of amino acids and ammonia in the serum. Clinical features, which are more prominent in males, include seizures, behavioral alterations, episodic vomiting, lethargy, and coma. menkes, textbook of child neurology, 5th ed, pp49-50)

• An x-linked urea cycle metabolic disorder characterized by deficiency of ornithine carbamoyltransferase, resulting in the accumulation of amino acids and ammonia in the serum. Signs and symptoms include seizures, delayed growth, behavioral changes, ataxia, lethargy, and coma.

• An x-linked urea cycle metabolic disorder characterized by deficiency of ornithine transcarbamylase, resulting in the accumulation of ammonia in the serum. Symptoms include vomiting, lethargy, and coma.

• Inborn error of metabolism of the urea cycle due to ornithine carbomoyltransferase e.c. 2.1.3.3) deficiency associated with hyperammonemia and accumulation of ammonia in the brain and liver. In most cases the early symptoms appear within the first three days of life and include respiratory distress, feeding difficulty, hypotonia, lethargy, and death in untreated cases. Neonatal hyperammonemic coma lasting longer than 48 hours usually results in cortical atrophy and mental retardation. In late-onset otc deficiency the symptoms appear from 2 months to 44 years with normal appearance at birth, followed by irritability, vomiting, lethargy, seizures, delayed development, ataxia, and seizures. Accumulation of ammonium in the brain and blood usually follows a protein load or intermittent infection. Otc deficient patients are particularly sensitive to toxic effects of valproate.

Details

• E72.4 is a billable/specific ICD-10-CM code that can be used to indicate a diagnosis for reimbursement purposes.

• The 2023 edition of ICD-10-CM E72.4 became effective on October 1, 2022.

• This is the American ICD-10-CM version of E72.4 – other international versions of ICD-10 E72.4 may differ.