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Children's Health

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Medium Chain Acyl CoA Dehydrogenase Deficiency

It is possible that the main title of the report Medium Chain Acyl CoA Dehydrogenase 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.


Disorder Subdivisions

  • None

General Discussion

Medium chain acyl-CoA dehydrogenase (MCAD) deficiency is a rare genetic metabolic disorder characterized by a deficiency of the enzyme medium chain acyl-CoA dehydrogenase. This enzyme is found to be most active in the liver, certain white blood cells (leukocytes), and certain connective tissue cells (fibroblasts) and is necessary for the breakdown (oxidation) of certain fats (medium chain fatty acids). Failure to break down these fats can lead to the abnormal accumulation of fatty acids in the liver and the brain. Abnormally low levels of the MCAD enzyme may also hamper or interrupt other processes associated with the metabolism of fatty acids.

In infants with MCAD deficiency, symptoms may include recurrent episodes of unusually low levels of a certain sugar (glucose) in the blood (hypoglycemia), lack of energy (lethargy), vomiting, and/or liver malfunction. These symptoms are most frequently triggered when an affected infant does not eat for an extended period of time (fasting). In some cases, a viral illness (e.g., upper respiratory infection) that limits food intake may cause the symptoms to occur. MCAD deficiency is the most common disease in a group of disorders that involve abnormalities of fatty acid metabolism (fatty acid oxidation disorders [FODs]). MCAD deficiency is inherited as an autosomal recessive trait.


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

United Mitochondrial Disease Foundation
8085 Saltsburg Road Suite 201
Pittsburgh, PA 15239
United States
Tel: (412)793-8077
Fax: (412)793-6477
Tel: (888)317-8633

Lactic Acidosis Support Trust
1A Whitley Close
Cheshire, CW10 0NQ
United Kingdom
Tel: 0160683719
Fax: 01606837198

Organic Acidemia Association
P.O. Box 1008
Pinole, CA 94564
Tel: (763)559-1797
Fax: (763)694-0017

Organic Acidaemias UK
5, Saxon Road
Middlesex, TW15 1QL
United Kingdom
Tel: 4401784245989

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

FOD (Fatty Oxidation Disorders) Family Support Group
PO Box 54
Okemos, MI 48864
Tel: (517)381-1940
Fax: (866)290-5206

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

14 Pembroke Street
Medford, MA 02155
Tel: (888)648-6228
Fax: (888)648-6228

Medical Home Portal
Dept. of Pediatrics
University of Utah
P.O. Box 581289
Salt Lake City, UT 84158
Tel: (801)587-9978
Fax: (801)581-3899

Childhood Liver Disease Research and Education Network
c/o Joan M. Hines, Research Administrator
Children's Hospital Colorado
13123 E 16th Ave. B290
Aurora, CO 80045
Tel: (720)777-2598
Fax: (720)777-7351

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: 4/11/2008
Copyright 1988, 1989, 1996, 1998, 2005 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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