hyperammonemia

(redirected from Hyperammonaemia)

hyperammonemia

 [hi″per-am″mo-ne´me-ah]
elevated levels of ammonia or its compounds in the blood. A congenital form occurs in two types: Type 1, due to deficiency of the enzyme ornithine carbamoyltransferase, is marked by vomiting, lethargy, coma, and hepatomegaly; symptoms are aggravated by protein ingestion. Type 2, due to deficiency of the enzyme carbamoyl phosphate synthetase (ammonia), is marked by vomiting, lethargy, and flaccidity and by elevated plasma and urinary levels of glycine. Hyperammonemia may also occur in nongenetic diseases such as severe liver disease.

am·mo·ne·mi·a

, ammoniemia (am'ō-nē'mē-ă, am'ō-ne-ē'mē-ă),
The presence of ammonia or some of its compounds in the blood, thought to be formed from the decomposition of urea; it usually results in subnormal temperature, weak pulse, gastroenteric symptoms, and coma.
Synonym(s): hyperammonemia
[ammonia + G. haima, blood]

hyperammonemia

/hy·per·am·mo·ne·mia/ (-am″o-ne´me-ah) a metabolic disturbance marked by elevated levels of ammonia in the blood.

hyperammonemia

[hī′pəram′ōnē′mē·ə]
Etymology: Gk, hyper + (ammonia), haima, blood
abnormally high levels of ammonia in the blood. Ammonia is produced in the intestine, absorbed into the blood, and detoxified in the liver. It is also generated as a by-product of protein metabolism. An increased production of ammonia or a decreased ability to detoxify it increases the blood levels of ammonia. The disorder is controlled by low-protein diets, including essential amino acid mixtures. Untreated, the condition leads to hepatic encephalopathy, characterized by asterixis, vomiting, lethargy, coma, and death.

hyperammonemia

Metabolism A heterogeneous group of five largely AR inborn errors of metabolism; each has a defect in a urea cycle enzyme–arginase, argininosuccinase, argininosuccinic acid synthetase, carbamyl phosphate synthetase, ornithine transcarbamylase; all begin in late infancy or childhood, except arginase deficiency, which is neonatal Clinical Accumulation of urea precursors–eg, ammonia, glutamine causes progressive lethargy, hyperthermia, apnea, hyperammonemia Diagnosis may be established in utero by restriction fragment–RFLP analysis Treatment Restrict dietary protein; activate alternate pathways of waste nitrogen excretion–eg, sodium benzoate or dietary supplementation with arginine

hyperammonemia, hyperammoniemia

1. the presence of ammonia in excess of the normal range of concentration of ammonia in the blood.
2. a metabolic disorder marked by elevated levels of ammonia or ammonium ion in the blood. One of the effects of severe hepatic dysfunction. May cause hepatic encephalopathy.
References in periodicals archive ?
We also suspected inborn errors of metabolism as his liver function worsened with the appearance of hyperammonaemia and tyrosinaemia.
People with this mutation also develop a surplus of ammonia - known as hyperammonaemia - which can equally have serious repercussions on brain function.
In our case, elevated transaminases were present even before she had a hypotension and the pattern of deranged metabolic and synthetic functions of liver seen in our patient in the form of elevated INR and profound hyperammonaemia, is not typical of ischemic liver injury.
Two generic medicines received a positive opinion from the CHMP: Febuxostat Mylan (febuxostat) for the prevention and treatment of hyperuricaemia and Ucedane (carglumic acid) for the treatment of hyperammonaemia due to N-acetylglutamate synthase primary deficiency.
The FDA has also approved the use of Ammonul as an adjunctive therapy in paediatric and adult patients to treat acute hyperammonaemia.
The Hyperammonaemia Knowledge Centre has been developed to raise awareness of this rare yet life-threatening condition.
High-dose 5-fluorouracil infusional therapy is associated with hyperammonaemia, lactic acidosis and encephalopathy.
Other complications include liver failure, cirrhosis, pulmonary arterial hypertension and metabolic abnormalities such as hypergalactosaemia and hyperammonaemia.
Although it is classically associated with hyponatraemia, it can also cause hyperglycinaemia, hyperammonaemia or simply hypo-osmolality, depending on the irrigation fluid being used.
A medical expert involved in the tragedy said: "The death certificate says the cause was hyperammonaemia.
Ornithine oxoglutarate was originally used to treat cirrhotic patients, with the aim of reducing blood ammonia levels, as hyperammonaemia was thought to be the main cause of hepatic encephalopathy(3).