Understanding Your Laboratory Test: What It Is and Why Your Doctor Ordered It
This test checks for the presence of beta aminoisobutyrate and proline in your urine, which are amino acids that can indicate certain metabolic conditions.
{"This test detects beta aminoisobutyrate and proline in urine","It helps screen for rare amino acid metabolism disorders","Positive results may indicate a genetic metabolic condition","Follow-up testing is usually needed if results are abnormal","The test is part of newborn screening or metabolic disease investigation"}
Key facts at a glance
- LOINC
- 15141-5
- Short code
- BAIBPRO
- Synonyms
- B-AIB+Pro Ur Ql
- Category
- chemistry
- Sample
- urine
- Container
- Sterile, screw-capped plastic urine container without preservatives; for transport, use leak-proof secondary container
- Units
- N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Method
- Ion exchange chromatography with ninhydrin detection (amino acid analysis)
- CPT
- 82139
- SNOMED
- 44070009
- Specimen volume
- 10-20 mL of random or 24-hour urine collection
- Stability
- Stable for 24 hours at 2-8°C; for prolonged storage, freeze at -20°C or below. Avoid repeated freeze-thaw cycles.
- Hemolysis max
- 0
- Lipemia max
- 0
- Icterus max
- 0
- TAT
- 48–168 hours
- Order
- routine
This test is a laboratory procedure that measures specific substances in a sample taken from your body, most often blood or urine. Your healthcare provider uses the results to evaluate how well certain organs and body systems are working and to gather objective information about your overall health.
The Beta Aminoisobutyrate and Proline test is a urine test that checks for the presence of two specific amino acids: beta aminoisobutyrate (BAIB) and proline. Amino acids are the building blocks of proteins, and their proper metabolism is essential for good health. This test helps healthcare providers detect abnormal levels of these substances in your urine.
A trained healthcare professional will collect a small sample, usually by drawing blood from a vein in your arm with a thin needle or by asking you to provide a urine specimen. The sample is then labeled and sent to a certified laboratory, where specialized equipment analyzes it and the results are reported back to your provider.
A urine sample is collected from the patient, typically in the morning for best results. The sample is then sent to a laboratory where it is analyzed using specialized techniques to detect the presence and concentration of beta aminoisobutyrate and proline. No special preparation is usually required, but your healthcare provider may give you specific instructions.
Your doctor may order this test to help diagnose a medical condition, check how a known condition is progressing, or see how well a treatment is working. It can also be part of a routine checkup to screen for early signs of disease before symptoms appear, so that any concerns can be addressed promptly.
This test is typically ordered as part of a metabolic screening panel, especially in newborns or when a doctor suspects an amino acid metabolism disorder. It may also be used to monitor patients with known metabolic conditions or to evaluate unexplained symptoms such as developmental delays, neurological problems, or failure to thrive.
Reference range
Beta-aminoisobutyrate: Normally present in trace to small amounts in urine. Elevated levels may be observed in some healthy individuals due to genetic polymorphism (high excretors). Proline: Normally present in trace amounts. Elevated levels (hyperprolinemia) may indicate prolinemia type I or II.N/A
No special preparation required. Patient should maintain usual diet and hydration status prior to collection unless otherwise specified by the clinician.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Elevated levels of beta aminoisobutyrate in urine may indicate beta-aminoisobutyric aciduria, a rare genetic disorder that affects amino acid metabolism. This condition is usually benign but may be associated with developmental delays in some cases. Elevated proline levels may indicate hyperprolinemia, which can be a sign of genetic mutations affecting proline metabolism. Both conditions may require further genetic testing and specialist consultation for proper diagnosis and management.
Frequently asked questions
Is this test painful?
What do abnormal results mean?
Do I need to fast before this test?
How long does it take to get results?
Sources
- 1
- 2
Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.
This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.
Medically reviewed by WellAlly Editorial Team Last reviewed August 16, 2026. · Read our editorial policy