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Children's Health

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N-Acetylglutamate Synthetase Deficiency

It is possible that the main title of the report N-Acetylglutamate Synthetase Deficiency is not the name you expected. Please check the synonyms listing to find the alternate name(s) and disorder subdivision(s) covered by this report.


  • hyperammonemia due to N-acetylglutamate synthetase deficiency
  • NAGS deficiency

Disorder Subdivisions

  • None

General Discussion

N-acetylglutamate synthetase (NAGS) deficiency is a rare genetic disorder characterized by complete or partial lack of the enzyme N-acetylglutamate synthetase (NAGS). NAGS is one of six enzymes that play a role in the break down and removal of nitrogen from the body, a process known as the urea cycle. The lack of the NAGS enzyme results in excessive accumulation of nitrogen, in the form of ammonia, in the blood (hyperammonemia). Excess ammonia, which is a neurotoxin, travels to the central nervous system through the blood, resulting in the symptoms and physical findings of NAGS deficiency. Symptoms include vomiting, refusal to eat, progressive lethargy, and coma. NAGS deficiency is inherited as an autosomal recessive trait.

The urea cycle disorders are a group of rare disorders affecting the urea cycle, a series of biochemical processes in which nitrogen is converted into urea and removed from the body through the urine. Nitrogen is a waste product of protein metabolism. Failure to break down nitrogen results in the abnormal accumulation of nitrogen, in the form of ammonia, in the blood.


CLIMB (Children Living with Inherited Metabolic Diseases)
Climb Building
176 Nantwich Road
Crewe, CW2 6BG
United Kingdom
Tel: 4408452412173
Fax: 4408452412174

National Urea Cycle Disorders Foundation
75 South Grand Avenue
Pasadena, CA 91105-1602
Tel: (626)578-0833
Fax: (626)578-0823
Tel: (800)386-8233

American Kidney Fund, Inc.
11921 Rockville Pike
Suite 300
Rockville, MD 20852
Tel: (800)638-8299

National Kidney Foundation
30 East 33rd Street
New York, NY 10016
Tel: (212)889-2210
Fax: (212)689-9261
Tel: (800)622-9010

NIH/National Institute of Diabetes, Digestive & Kidney Diseases
Office of Communications & Public Liaison
Bldg 31, Rm 9A06
31 Center Drive, MSC 2560
Bethesda, MD 20892-2560
Tel: (301)496-3583

Genetic and Rare Diseases (GARD) Information Center
PO Box 8126
Gaithersburg, MD 20898-8126
Tel: (301)251-4925
Fax: (301)251-4911
Tel: (888)205-2311
TDD: (888)205-3223

Madisons Foundation
PO Box 241956
Los Angeles, CA 90024
Tel: (310)264-0826
Fax: (310)264-4766

Urea Cycle Disorders Consortium
Children's National Medical Center
111 Michigan Avenue, NW
Washington, DC 20010
Tel: (815)333-4014

For a Complete Report:

This is an abstract of a report from the National Organization for Rare Disorders (NORD). A copy of the complete report can be downloaded free from the NORD website for registered users. The complete report contains additional information including symptoms, causes, affected population, related disorders, standard and investigational therapies (if available), and references from medical literature. For a full-text version of this topic, go to and click on Rare Disease Database under "Rare Disease Information".

The information provided in this report is not intended for diagnostic purposes. It is provided for informational purposes only. NORD recommends that affected individuals seek the advice or counsel of their own personal physicians.

It is possible that the title of this topic is not the name you selected. Please check the Synonyms listing to find the alternate name(s) and Disorder Subdivision(s) covered by this report

This disease entry is based upon medical information available through the date at the end of the topic. Since NORD's resources are limited, it is not possible to keep every entry in the Rare Disease Database completely current and accurate. Please check with the agencies listed in the Resources section for the most current information about this disorder.

For additional information and assistance about rare disorders, please contact the National Organization for Rare Disorders at P.O. Box 1968, Danbury, CT 06813-1968; phone (203) 744-0100; web site or email

Last Updated: 3/17/2011
Copyright 1986, 1987, 1990, 1992, 1993, 1997, 1998, 2001, 2011 National Organization for Rare Disorders, Inc.

WebMD Medical Reference from the National Organization for Rare Disorders

Last Updated: May 28, 2015
This information is not intended to replace the advice of a doctor. Healthwise disclaims any liability for the decisions you make based on this information.

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