Serum or plasma substance concentration (e.g., protein or peptide) measured by immunoassay
This test measures the amount of a specific substance in your blood, often a protein or peptide, using a sensitive detection method.
["It helps assess levels of important molecules that may affect health, such as hormones, enzymes, or markers of disease."]
Key facts at a glance
- LOINC
- 92719-4
- Short code
- IDL large Ser-sCnc
- Synonyms
- IDL large Ser-sCnc
- Category
- chemistry
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Specimen volume
- 5 mL
- Stability
- Room temperature: 4h, Refrigerated: 24h, Frozen: 7d
- Hemolysis max
- 500
- Lipemia max
- 1000
- Icterus max
- 500
- TAT
- 4–24 hours
- Order
- routine
Your healthcare provider may order this test to look for the cause of symptoms you are having, to check how well an organ or body system is working, to screen for a condition before it causes problems, or to monitor a treatment you are already receiving.
Your healthcare provider may recommend this test to check for certain conditions, monitor treatment progress, or investigate symptoms like fatigue, weight changes, or unusual lab results. It could also be part of a routine screening or diagnostic workup for conditions affecting blood chemistry or immune function.
Before your test, your care team will explain what will happen and give you any instructions you need to follow. Tell them about all medicines, vitamins, and supplements you take, along with any allergies or other health conditions, so they can keep you safe during the test.
No special preparation is usually needed, but you may be asked to fast for a few hours if the test involves blood drawn from a vein. If you’re taking certain medications, let your provider know beforehand.
The test is usually performed in a clinic, hospital, or laboratory by trained staff who will guide you through each step. The procedure is often quick, but let the team know right away if you feel pain, dizziness, or any other discomfort while it is being done.
A healthcare professional will draw blood from a vein in your arm using a needle. You may feel a slight pinch, but the procedure is quick. The blood sample is then sent to a lab for analysis using an immunoassay method to detect and measure the substance accurately.
Your results will show whether your measurements fall inside the normal range for this test. Results that are within range may be reassuring, while abnormal results can point to a condition that needs closer attention. Your provider will explain what your numbers mean and discuss any follow-up care with you.
Results will show the concentration of the substance in your blood. While reference ranges vary by substance, abnormal levels may signal potential health issues, such as hormone imbalances, infections, or metabolic disorders. Your provider will interpret the results in the context of your overall health and symptoms.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Clinical Significance
Frequently asked questions
This test can identify imbalances or changes in substances critical to bodily functions, such as inflammation markers, enzymes, or proteins like hormones or antibodies. For example, it may help diagnose autoimmune conditions, endocrine disorders, or detect early signs of disease progression.
If your results are outside expected ranges, your healthcare provider will discuss them with you. They may recommend further testing, adjustments to your treatment plan, or additional evaluations to understand the cause of the abnormality.
Most likely, you can eat and drink normally unless your provider specifies otherwise. If fasting is required, follow their instructions carefully to ensure accurate results.
Sources
- 1
- 2Lab Tests OnlineSource
- 3
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