Maple Syrup Urine Disorder Neonatal Screen Blood Test

The MSUD test measures the level of certain amino acids in newborns' blood.

• To detect the absence of an enzyme responsible for metabolising these acids, which may result in MSUD.
• It helps identify infants with MSUD early before symptoms appear so that treatment can begin immediately and prevent complications.

This test can be conducted on newborn babies aged between 48 hours to 5 days. It is recommended if

• There is a family history of MSUD.
• The baby is born with low muscle tone or lethargy.
• The newborn has seizures, especially before 2 weeks of age.
• The newborn demonstrates poor feeding.

If the test shows elevated amino acid levels in the newborn, they may have MSUD. The physician will interpret these results and recommend confirmatory follow-up tests as required. 

The test involves taking a blood sample by pricking the baby’s heel or finger. The procedure is simple, quick, and relatively painless, quite similar to a routine vaccination shot. Results are usually available within 24 hours. 

There are no specific preparations necessary for taking this test. However, physicians suggest not feeding the baby for one to two hours before testing to ensure the accuracy of the results.

Other tests that may be recommended alongside this test include measuring amino acids through plasma, measuring branched-chain keto acids in urine, and genetic testing to confirm the MSUD diagnosis.

Amino acid screening or neonatal bloodspot screening

MSUD is an inherited metabolic disorder that limits or prevents the body's ability to process certain amino acids found in food proteins, leading to a buildup of harmful substances in the blood. MSUD can cause neurological symptoms such as developmental delay, seizures, coma, and even death if left untreated.