Ornithine transcarbamylase (OTC) deficiency
What are the first steps after an initial diagnosis of ornithine transcarbamylase deficiency?
Since most infants with ornithine transcarbamylase deficiency (OTC) are not diagnosed until after a life-threatening illness (ammonia levels are severely elevated), rescue therapy is begun immediately. The fastest method for lowering the ammonia level is hemodialysis. A neonate should not be hemodialysed longer than four hours and should then be switched to hemofiltration for stabilization to prevent a rebound of the ammonia level. An older individual can be dialysed longer and should also be switched to hemofiltration for stabilization.
Ammonia scavenger therapy treatment allows an alternative pathway for the excretion of excess nitrogen. Nitrogen scavenger therapy is available as an intravenous infusion of a mixture of sodium phenylacetate and sodium benzoate for acute management and as an oral preparation of phenylbutyrate or sodium benzoate for long-term maintenance therapy.
If an older or seemingly asymptomatic individual is diagnosed with OTC, they will work closely with metabolic dietitians and medical geneticists as they learn more about the individual and do additional blood tests to develop the best treatment and monitoring plan for that individual which may include following a low protein diet and taking medicines such as citrulline.
A medical geneticist can be found by asking your doctor for a referral or looking on the American College of Medical Geneticists website. Genetic counselors can be found on the National Society of Genetic Counselors website. A metabolic dietician can be found through the Genetic Metabolic Dieticians International webpage.
SOURCE: Emory University - Department of Human Genetics in collaboration with ThinkGenetic • https://www.thinkgenetic.com/diseases/ornithine-transcarbamylase-deficiency/treatment/18600 • DATE UPDATED: 2019-12-03
GeneReviews. Ornithine transcarbamylase deficiency. Last update: 2016.
NORD, Ornithine Transcarbamylase Deficiency, https://rarediseases.org/rare-diseases/ornithine-transcarbamylase-deficiency/