Hyperammonemia

	WikiDoc Resources for Hyperammonemia
Articles
Most recent articles on Hyperammonemia Most cited articles on Hyperammonemia Review articles on Hyperammonemia Articles on Hyperammonemia in N Eng J Med, Lancet, BMJ
Media
Powerpoint slides on Hyperammonemia Images of Hyperammonemia Photos of Hyperammonemia Podcasts & MP3s on Hyperammonemia Videos on Hyperammonemia
Evidence Based Medicine
Cochrane Collaboration on Hyperammonemia Bandolier on Hyperammonemia TRIP on Hyperammonemia
Clinical Trials
Ongoing Trials on Hyperammonemia at Clinical Trials.gov Trial results on Hyperammonemia Clinical Trials on Hyperammonemia at Google
Guidelines / Policies / Govt
US National Guidelines Clearinghouse on Hyperammonemia NICE Guidance on Hyperammonemia NHS PRODIGY Guidance FDA on Hyperammonemia CDC on Hyperammonemia
Books
Books on Hyperammonemia
News
Hyperammonemia in the news Be alerted to news on Hyperammonemia News trends on Hyperammonemia
Commentary
Blogs on Hyperammonemia
Definitions
Definitions of Hyperammonemia
Patient Resources / Community
Patient resources on Hyperammonemia Discussion groups on Hyperammonemia Patient Handouts on Hyperammonemia Directions to Hospitals Treating Hyperammonemia Risk calculators and risk factors for Hyperammonemia
Healthcare Provider Resources
Symptoms of Hyperammonemia Causes & Risk Factors for Hyperammonemia Diagnostic studies for Hyperammonemia Treatment of Hyperammonemia
Continuing Medical Education (CME)
CME Programs on Hyperammonemia
International
Hyperammonemia en Espanol Hyperammonemia en Francais
Business
Hyperammonemia in the Marketplace Patents on Hyperammonemia
Experimental / Informatics
List of terms related to Hyperammonemia

	Hyperammonemia;
ICD-10	E72.2
ICD-9	270.6
DiseasesDB	20468
eMedicine	neuro/162 ped/1057
MeSH	D022124

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]

Overview

Hyperammonemia (or 'hyperammonaemia') is a metabolic disturbance characterised by an excess of ammonia in the blood. It is a dangerous condition that may lead to encephalopathy and death. It may be primary or secondary.

Ammonia is a substance that contains nitrogen. It is a product of the catabolism of protein. It is converted to the non-toxic substance urea prior to excretion in urine by the kidneys. The metabolic pathways that synthesise urea are located first in the mitochondria and then into the cytosol. The process is known as the urea cycle, which comprises several enzymes acting in sequence.

Types

Primary vs. secondary

Primary hyperammonemia is caused by several inborn errors of metabolism that are characterised by reduced activity of any of the enzymes in the urea cycle.
Secondary hyperammonemia is caused by inborn errors of intermediary metabolism characterised by reduced activity in enzymes that are not part of the urea cycle (e.g .Propionic acidemia, Methylmalonic acidemia) or dysfunction of cells that make major contributions to metabolism (eg hepatic failure).