Maple Syrup Urine Disease
National Organization for Rare Disorders, Inc.
It is possible that the main title of the report Maple Syrup Urine Disease 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.
- BCKD Deficiency
- Branched Chain Alpha-Ketoacid Dehydrogenase Deficiency
- Branched Chain Ketonuria I
- Classical Maple Syrup Urine Disease
- Intermittent Maple Syrup Urine Disease
- Intermediate Maple Syrup Urine Disease
- Thiamine-Responsive Maple Syrup Urine Disease
- Classic Maple Syrup Urine Disease
Maple syrup urine disease (MSUD) is a rare genetic disorder characterized by deficiency of certain enzymes (branched-chain alpha-keto acid dehydrogenase complex) required to breakdown (metabolize) specific amino acids in the body. Because these amino acids are not metabolized, they, along with their various byproducts, abnormally accumulate in the cells and fluids of the body. Such accumulation can cause a variety of symptoms including lethargy, irritability, poor feeding, abnormal movements and a characteristic odor of maple syrup in the earwax (cerumen), sweat and urine of affected individuals. In addition, if untreated various neurological complications including seizures, coma and brain damage may occur. Failure to promptly detect and treat MSUD can lead to life-threatening complications. However, the disorder can be successfully managed through a specialized diet. Even with treatment affected individuals remain at risk for developing episodes of acute illness (metabolic crisis) often triggered by infection, injury, failure to eat (fasting) or psychological stress. During these episodes there is a rapid, sudden spike in amino acid levels necessitating immediate medical intervention.
At least four subtypes of MSUD have been identified in the medical literature. Some researchers include a fifth subtype, although other researchers consider this a separate distinct disorder. The various subtypes of MSUD have different levels of residual enzyme activity, different severity, and different ages of onset. All forms are inherited as autosomal recessive traits.
CLIMB (Children Living with Inherited Metabolic Diseases)
176 Nantwich Road
Crewe, CW2 6BG
March of Dimes Birth Defects Foundation
1275 Mamaroneck Avenue
White Plains, NY 10605
1825 K Street NW, Suite 1200
Washington, DC 20006
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
Maple Syrup Urine Disease Family Support Group
9517 Big Bear Ave
Powell, OH 43065
Belgian Association for Metabolic Diseases
Alice Nahonlann 7
Genetic and Rare Diseases (GARD) Information Center
PO Box 8126
Gaithersburg, MD 20898-8126
PO Box 241956
Los Angeles, CA 90024
Cook for Love, Inc.
30 Seneca Street
Dobbs Ferry, NY 10522
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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.
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Last Updated: 8/7/2007
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