Platform
Company
Urinalysis
Review status
Currently under review
Pending specialist review and validation.
Urine Proline measures the amount of the amino acid proline excreted in your urine. Proline is a building block of proteins and collagen, and your body both makes it and gets it from food. The test is usually part of a urine amino acids profile and is reported relative to creatinine to account for how diluted or concentrated the urine is.
This measurement helps your care team evaluate how your body processes proline and how your kidneys handle amino acids. It reflects metabolic pathways in the liver and kidneys and how well kidney tubules reabsorb amino acids. The test uses a simple urine sample.
Results can help screen for or monitor inherited conditions that affect proline metabolism, such as hyperprolinemia, and can point to kidney tubular problems where multiple amino acids are lost in urine. It is often ordered for infants or children with developmental concerns, seizures, or suspected metabolic disease, and in people being evaluated for generalized aminoaciduria.
Urine Proline can also offer clues during evaluation of liver disease, malnutrition, or increased tissue breakdown, and it may be used to follow treatment or dietary changes. Because it is noninvasive, it is a practical way to complement blood testing when investigating metabolic health.
Your result is interpreted using age-appropriate expectations and the creatinine-corrected value from your sample. A higher than expected value can be persistent, due to an inherited enzyme issue, or temporary, due to diet, dehydration, intense exercise, illness, or certain medicines. Your clinician will consider your symptoms, family history, and other labs before drawing conclusions.
A lower than expected value is usually not concerning on its own. If your result is unexpected, your clinician may recommend repeating the urine test, checking plasma amino acids, or arranging specialized genetic testing. Do not change your diet or medications without medical advice. If the sample was very dilute or concentrated, or if collection was not clean, a repeat first-morning sample may be requested.
Reference intervals vary by laboratory, analyzer, methodology, population, and units. The ranges shown here are for education only. Always interpret your results against the reference interval printed on your own lab report.
Very dilute or very concentrated urine can affect creatinine correction and the reliability of the result. First-morning samples reduce this variability and are often preferred.
High protein intake, collagen or gelatin-rich foods, and certain amino acid supplements can transiently raise urinary proline. Tell your clinician about your usual diet and any supplements.
Some anticonvulsants, corticosteroids, and other drugs can alter amino acid handling or increase catabolism, which may change urinary proline. Provide a full medication list, including over-the-counter products.
Infants and young children normally excrete more amino acids because kidney tubular reabsorption is still maturing. Age-specific interpretation is essential.
Fever, infections, strenuous exercise, and catabolic states can temporarily increase amino acid excretion. Repeat testing after recovery may be recommended.
Contamination from diapers, stool, or skin creams, and delays in refrigeration or processing can affect accuracy. Follow collection instructions carefully and use a clean container.
References