Maple syrup urine disease

(Redirected from Leucinosis)
Jump to navigation Jump to search

WikiDoc Resources for Maple syrup urine disease

Articles

Most recent articles on Maple syrup urine disease

Most cited articles on Maple syrup urine disease

Review articles on Maple syrup urine disease

Articles on Maple syrup urine disease in N Eng J Med, Lancet, BMJ

Media

Powerpoint slides on Maple syrup urine disease

Images of Maple syrup urine disease

Photos of Maple syrup urine disease

Podcasts & MP3s on Maple syrup urine disease

Videos on Maple syrup urine disease

Evidence Based Medicine

Cochrane Collaboration on Maple syrup urine disease

Bandolier on Maple syrup urine disease

TRIP on Maple syrup urine disease

Clinical Trials

Ongoing Trials on Maple syrup urine disease at Clinical Trials.gov

Trial results on Maple syrup urine disease

Clinical Trials on Maple syrup urine disease at Google

Guidelines / Policies / Govt

US National Guidelines Clearinghouse on Maple syrup urine disease

NICE Guidance on Maple syrup urine disease

NHS PRODIGY Guidance

FDA on Maple syrup urine disease

CDC on Maple syrup urine disease

Books

Books on Maple syrup urine disease

News

Maple syrup urine disease in the news

Be alerted to news on Maple syrup urine disease

News trends on Maple syrup urine disease

Commentary

Blogs on Maple syrup urine disease

Definitions

Definitions of Maple syrup urine disease

Patient Resources / Community

Patient resources on Maple syrup urine disease

Discussion groups on Maple syrup urine disease

Patient Handouts on Maple syrup urine disease

Directions to Hospitals Treating Maple syrup urine disease

Risk calculators and risk factors for Maple syrup urine disease

Healthcare Provider Resources

Symptoms of Maple syrup urine disease

Causes & Risk Factors for Maple syrup urine disease

Diagnostic studies for Maple syrup urine disease

Treatment of Maple syrup urine disease

Continuing Medical Education (CME)

CME Programs on Maple syrup urine disease

International

Maple syrup urine disease en Espanol

Maple syrup urine disease en Francais

Business

Maple syrup urine disease in the Marketplace

Patents on Maple syrup urine disease

Experimental / Informatics

List of terms related to Maple syrup urine disease

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor(s)-in-Chief:

For patient information, click here

Template:Search infobox

Template:DiseaseDisorder infobox

Overview

Maple syrup urine disease (MSUD) is an autosomal recessive metabolic disorder of amino acid metabolism. It is also called branched chain ketoaciduria.

This amino acid acidopathy is due to a deficiency of the metabolic enzyme branched chain α-keto acid dehydrogenase (BCKDH) leading to a buildup of branched-chain amino acids (leucine, isoleucine, and valine) in the blood and urine.

Historical Perspective

Classification

Maple syrup urine disease can be classified by its pattern of signs and symptoms or by its genetic cause.

The most common and most severe form of the disease is the classic type, which appears soon after birth. Variant forms of the disorder appear later in infancy or childhood and are typically less severe, but still involve mental and physical retardation if not treated.

There are several variations of the disease:

  • Classic Severe MSUD
  • Intermediate MSUD
  • Intermittent MSUD
  • Thiamine-responsive MSUD
  • E3-Deficient MSUD with Lactic Acidosis

Presentation

Characterized by an infant with sweet-smelling urine with an odor similar to that of maple syrup, infants with this disease seem healthy at birth but if left untreated suffer severe brain damage and eventually die. Because of the founder effect, MSUD has a much higher prevalence in children of Amish and Mennonite descent. [1] [2]

From early infancy, the condition is characterized by poor feeding, vomiting, lack of energy (lethargy), seizures, and mental health issues. The urine of affected infants has a distinctive sweet odor, much like burned caramel, that gives the condition its name.

Pathophysiology

Genetics

Maple syrup urine disease is inherited in an autosomal recessive pattern.

Maple syrup urine disease affects an estimated 1 in 185,000 infants worldwide.

Mutations in the following genes cause maple syrup urine disease:

These four genes produce proteins that work together as the branched-chain alpha-keto acid dehydrogenase complex. The complex is essential for breaking down the amino acids leucine, isoleucine, and valine, which are present in many kinds of food (particularly protein-rich foods such as milk, meat, and eggs).

Mutations in any of these genes reduce or eliminate the function of the enzyme complex, preventing the normal breakdown of leucine, isoleucine, and valine. As a result, these amino acids and their by-products build up in the body.

Because high levels of these substances are toxic to the brain and other organs, this accumulation leads to the serious medical problems associated with maple syrup urine disease. However recent breakthroughs have yielded treatments through liver transplants and gene therapy is on the rise.

Causes

Differentiating Maple syrup urine disease from Other Diseases

Epidemiology and Demographics

Risk Factors

Screening

Natural History, Complications, and Prognosis

Diagnosis

Diagnostic Criteria

History and Symptoms

Physical Examination

Laboratory Findings

Imaging Findings

Other Diagnostic Studies

Treatment

Treatment of the MSUD, like diabetes, requires careful monitoring of blood chemistry and involves both special diet and frequent testing.

A diet with minimal levels of the amino acids leucine, isoleucine, and valine must be maintained in order to prevent neurological damage. Usually, patients, or parents of patients are assisted by a physician or dietician. This diet must be adhered to strictly and permanently. However, with proper treatment those afflicted are able to live healthy, normal lives and not suffer the severe neurological damage that characterizes the untreated disease.

Medical Therapy

Surgery

Prevention

See also

Additional Resources

References

  1. Sailer, Christian, Wasner, Susanne. Differential Diagnosis Pocket. Hermosa Beach, CA: Borm Bruckmeir Publishing LLC, 2002:77 ISBN 1591032016
  2. Kahan, Scott, Smith, Ellen G. In A Page: Signs and Symptoms. Malden, Massachusetts: Blackwell Publishing, 2004:68 ISBN 140510368X

Template:Endocrine, nutritional and metabolic pathology

de:Ahornsirupkrankheit ms:Penyakit Kencing Sirap Maple

Template:WS Template:WH