MAPLE SYRUP URI NE DI SEASE (MSUD) I S A  METAB OLI SM DI SOR DER PASSED DOWN THROUGH FAMI LIES I N WHICH THE B OD Y CANNOT B REAK D OWN CERTAI N PARTS OF

PROTEI NS. URI NE IN PERSONS W ITH THI S C ONDIT I ON

CAN SMELL L I KE MAPLE SYRUP.

Maple syrup urine disease

Amnah Mahroo

Maple syrup urine disease (MSUD)

a metabolic disorder of branched chain amino acids

caused by a deficiency of the branched-chain alpha-keto acid dehydrogenase complex (BCKDC)

Accumulation of leucine Isoleucine and  valine in the blood and urine

Genetic prevalence

Maple syrup urine disease affects approximately 1 out of 180,000 infants

autosomal recessive disorderfour genes produce proteins that work

together as the (BCKDC) complex

BCKDHABCKDHBDBTDLD

Diagnosis and Symptoms

presence of sweet-smelling urine and earwax poor appetite weak suck weight loss high pitched cry Vomiting

If not treated, other symptoms can follow:  swelling of the brain seizures metabolic acidosis mental retardation or spasticity coma, sometimes leading to death

Signs and tests

Plasma amino acid testUrine amino acid test

Newborn screening tests Inborn errors of metabolism

Isoleucine•Children: 37 to 140•Adults: 42 to 100

Leucine•Children: 70 to 170•Adults: 66 to 170

Valine•Children: 160 to 350•Adults: 150 to 310

PLASMA AMINO ACID CONCENTRATIONS

TREATMENT FOR MSUD

A protein-free dietA special medical formula as a substitute for milkFluids, sugars and fats are given through a vein

(IV)Diet low in branched-chain amino acidsThiamine Supplements Tracking BCAA levelsDialysisLiver transplantationhttp://www.newbornscreening.info/Parents/amino

aciddisorders/MSUD.html

Prevention

Genetic counselingGenetic testing (DNA testing)Carrier testing

References

The MSUD Family Support Grouphttp://www.msud-support.org/

CLIMB (Children Living with Inherited Metabolic Disorders)http://www.climb.org.uk

Genetic Alliancehttp://www.geneticalliance.org/

http://www.newbornscreening.info/Parents/aminoaciddisorders/MSUD.html

http://www.ncbi.nlm.nih.gov/pubmedhealth/PMH0001411/ http://en.wikipedia.org/wiki/Maple_syrup_urine_disease http://www.nlm.nih.gov/medlineplus/ency/article/000373.ht

m http://

emedicine.medscape.com/article/946234-overview#a0104 http://www.ncbi.nlm.nih.gov/pubmedhealth/PMH0001411/