Ornithine Transcarbamylase Deficiency (OTC)



Ornithine transcarbamylase deficiency (OTC) is a condition in which the body is unable to process and remove waste, causing dangerous amounts of ammonia to build up in the blood. This can result in severe mental disability, seizures, and a variety of other life-threatening medical problems.  OTC varies widely in its severity and age of onset. Most babies develop signs of OTC within the first few days of life. Early signs of OTC include developmental delays, poor appetite, sleeping longer or more often, tiredness, irritability, vomiting, trouble breathing, Involuntary or uncontrolled body movements, and trouble regulating body temperature. Some individuals with OTC may not show any signs or symptoms until later in life. These later onset cases are usually less severe than those that develop in infancy. 

Condition Type:



Estimates of the prevalence of ornithine transcarbamylase deficiency (OTC) have ranged from 1 in 14,000 to 1 in 77,000 people.

More Information for Parents:
Also known as:
  • OTC
  • Ornithine carbamoyltransferase deficiency disease
  • Hyperammonemia due to ornithine transcarbamylase deficiency

Core Conditions