Initial symptoms, beginning with protein ingestion, may include:
- A maple syrup odor of cerumen, which can be present by 3 days of age
- Elevated branched-chain amino acids, leucine, isoleucine, and valine; presence of allo-isoleucine detectable shortly after birth, but can be missed by the newborn screening in milder forms of the disease or if the sample is obtained too early (<12h after birth)
- Ketonuria becomes evident after branched-chain amino acids become elevated
- Irritability, poor feeding, vomiting
- Intermittent apnea
- Repetitive "fencing" or "bicycling" movements
- Coma and central respiratory failure
Variant forms of the disease may have milder and later onset of symptoms and present with anorexia, poor growth, irritability, or developmental delay in late infancy or childhood. Symptoms and metabolic crisis episodes may be precipitated by illnesses. Urine may also have a maple syrup odor, especially during metabolic crisis. One variant is responsive to thiamine.
- Contact the family and evaluate the infant for poor feeding, lethargy, irregular breathing pattern.
- Provide emergency treatment and referral for lethargy, tachypnea, alternating hypertonia/hypotonia, or seizures. See ACT Sheet for Maple Syrup Urine Disease (ACMG) ( 369 KB) for additional information.
- Discontinue breast or cow milk formula feeding, substitute a special leucine-, valine-, and isoleucine-free formula.
- Confirm the diagnosis, work with the following service(s): see all see all Newborn Screening Programs services providers (3) in our database.
- Evaluate and continue ongoing collaborative management, consult the following service(s): Pediatric Medical Genetics, (801-213-3599); See also Services below.
- Educate the family about signs, symptoms, and the need for urgent care if the infant becomes ill. See Maple Syrup Urine Disease - Information for Parents (STAR-G).
- Support initiation and maintenance of dietary restriction of branched-chain amino acids (found in animal and vegetable food sources) and use of medical formulas. Provide protein as essential, and non-essential amino acids and supplementation with isoleucine or valine as needed.
- Consider thiamine for children with the thiamine-responsive variant.
- See patients readily when illness occurs since that is the primary cause of decompensation. Facilitate monitoring of urinary BCKA excretion with DNPH reagent strips at home. Measure amino acid levels through blood tests when indicated.
- Admit to the hospital and seek expert assistance for management for any decompensation that does not promptly respond to outpatient treatment.
- Assist in management of irreversible consequences as necessary, particularly with developmental and educational interventions.
- See the Portal’s diagnosis and management module for Maple Syrup Urine Disease (MSUD).
Maple Syrup Urine Disease - Information for Professionals (STAR-G)
Structured list of information about the condition and links to more information; Screening, Technology, and Research in Genetics.
Maple Syrup Urine Disease (GeneReviews)
Excellent review by Kevin A. Strauss, MD, Erik G. Puffenberber, MD and D. Holmes Morton, MD including clinical description, differential, management, genetic counseling, molecular genetics, and a bibliography.
Maple Syrup Urine Disease Acute Illness Protocol (NECMP)
Guideline for clinicians treating the sick infant/child who has previously been diagnosed with maple syrup urine disease (MSDU); developed under the direction of Dr. Harvey Levy, Senior Associate in Medicine/Genetics at Children’s Hospital Boston, and Professor of Pediatrics at Harvard Medical School, for the New England Consortium of Metabolic Programs. Click PDF to view the complete protocol.
Utah Newborn Screening Program (UDOH)
Provides information about the program, related legislation, training for practices, and newborn conditions; Utah Department of Health.
Genetics in Primary Care Institute (AAP)
The goal of this site is to increase collaboration in the care of children with known or suspected genetic disorders. It includes health supervision guidelines and other useful resources; represents a collaboration among the Health Resources & Services Administration, the Maternal and Child Health Bureau, and the American Academy of Pediatrics.
Maple Syrup Urine Disease Family Support Group
A non-profit organization that provides information, newsletters and articles, family stories, support services, recipes and formulas, and dietary resources.
Maple Syrup Urine Disease - Information for Parents (STAR-G)
A fact sheet, written by a genetic counselor and reviewed by metabolic and genetic specialists, for families who have received an initial diagnosis of a newborn disorder; Screening, Technology and Research in Genetics.
Maple Syrup Urine Disease (Genetics Home Reference)
Excellent, detailed review of condition for patients and families; sponsored by the U.S. National Library of Medicine.
National Newborn Screening & Global Resource Center (NNSGRC)
Fact sheets, data reports, publications, and information for clinicians about genetic screening that includes links to state genetic contacts.
What is Maple Syrup Urine Disease (MSUD)? (GSLC)
A brief educational overview of the genetics of maple syrup urine disease (MSUD) from the Genetic Science Learning Center at the University of Utah.
ACT Sheet for Maple Syrup Urine Disease (ACMG) ( 369 KB)
Contains short-term recommendations for clinical follow-up of the newborn who has screened positive; American College of Medical Genetics.
Confirmatory Algorithm for MSUD (ACMG)
Resource for clinicians to help confirm diagnosis; American College of Medical Genetics.
See all Newborn Screening Programs services providers (3) in our database.
See all Pediatric Genetics services providers (5) in our database.
For other services related to this condition, browse our Services categories or search our database.
|Author:||Nicola Longo, MD, PhD - 12/2015|
|Content Last Updated:||12/2015|
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