On a busy Friday noon, an urgent request from a local children’s hospital notified Baylor Genetics that a 10-day-old baby failed newborn screening (NBS) and was suspicious of maple syrup urine disease (MSUD). MSUD is a rare, inherited disorder caused by decreased activity of the branched-chain alpha-ketoacid dehydrogenase complex (BKCD), the second enzymatic step in the degradative pathway of the branched-chain amino acids (BCAAs).1 In layman’s terms, MSUD inhibits one’s body to breakdown a major part of protein, which can cause neurologic damage. The name comes from patients’ urine having a maple syrup odor.
Samples of the baby’s plasma amino acids (test code: 4100) and urine organic acids (test code: 4200) were collected for stat testing and sent to BG’s Biochemistry Lab. In three short hours, once the samples were received at the lab, the amino acid report for the baby was sent to the physicians via secure message. The report confirmed the diagnosis of MSUD. Over the weekend and weeks to follow, dozens of tests were performed on the baby promptly for the purpose of clinical treatment and diet monitoring.
NBS is one of the most successful preventive health programs. In the United States, over 98 percent of babies participate in NBS by providing a dried blood spot sample within two days of birth. Through this public program, more than 13,000 newborns are identified with significant rare genetic conditions. Most conditions identified in NBS are treatable if early medical interventions are implemented before irreversible health damages. As the result, these newborns may live a normal healthy life, saving significant costs for the family and the society. For example, phenylketonuria (PKU) costs around $1-2 billion annually in care for patients that had delayed diagnoses. The annual costs associated with screening and early treatment are much lower, around $342 million.
Our Metabolic Tests include:
- Targeted Panels
- Amino Acid Analysis (test codes: 4100, 4160, 4240)
- Organic Acid Screen (test code: 4200)
- Succinylacetone Determination (test code: 4250)
- Methylmalonic Acid (test code: 4150)
- Nitrogen Scavenger Medication Monitoring (Phenylbutyrate Metabolite Analysis, test codes: 4650, 4651)
- Enzyme Analysis
- Biotinidase Enzyme Analysis (test code: 4555)
- Arginase Enzyme Analysis (test code: 4536)
- Untargeted Metabolomics
- Global MAPS® (test code: 4900, 4901)
In addition to metabolic tests, molecular tests, such as panels (single gene and multiple genes), are available for follow-up testing of NBS results. For further information, please contact BG’s Client Relations Division at [email protected].
- Strauss KA, Puffenberger EG, Carson VJ. Maple Syrup Urine Disease. 2006 Jan 30 [Updated 2020 Apr 23]. In: Adam MP, Ardinger HH, Pagon RA, et al., editors. GeneReviews® [Internet]. Seattle (WA): University of Washington, Seattle; 1993-2021. Available from: https://www.ncbi.nlm.nih.gov/books/NBK1319/