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Unspecified Analyte, Serum/Plasma — Mass Concentration

Published: August 9, 2026Updated: August 16, 2026

Measures the concentration of a substance in serum or plasma. The abbreviation “afsh” does not unambiguously identify the substance.

Quick summary

["This test measures how much of a specific substance is present in a blood sample, but the analyte should be confirmed with your healthcare provider."]

Medically reviewed by WellAlly Editorial TeamLast reviewed August 16, 2026Editorial policy

Key facts at a glance

LOINC
27140-3
Short code
A-FSH SerPl-mCnc
Synonyms
A-FSH SerPl-mCnc
Category
liver
Sample
serum
Container
Red-top tube (SST)
Units
N/A
Ref low
3.5
Ref high
12.5
Fasting
false
Population
adult
Sex
all
Age range
18–65 years
CPT
83001
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

What is this test?

This is a blood test that measures the mass concentration of a substance in serum or plasma, meaning the amount of the substance per unit volume. The abbreviation in the test code is not specific enough to determine which substance is being measured, so check the full test name with your healthcare provider or laboratory.

Why might I need this test?

Concentration testing may be used to evaluate health, diagnose or monitor a condition, or check the effect of treatment. The reason for testing depends on the substance being analyzed.

How is the test performed?

A healthcare professional draws blood into a collection tube. The sample is processed to separate serum or plasma, and the laboratory uses a validated method to measure the concentration of the substance.

How do I prepare for the test?

Special preparation is often unnecessary, but follow any instructions from your healthcare provider. Fasting or testing at a specific time may be required for certain substances, so confirm the preparation before your appointment.

Reference range

Follicular: 3.5-12.5 mIU/mLN/A

Specimen: serum

For females: inform if menstrual cycle status. For certain tests, timing within menstrual cycle may matter.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

◆Associated findings1

Short name

Serum/plasma analyte mass concentration

Frequently asked questions

Which substance does this test measure?
The code does not clearly identify the analyte. Ask your healthcare provider or laboratory for the complete test name before using the result to make health decisions.
Is serum or plasma used for this test?
The test is performed on serum or plasma, both obtained from a blood sample. The laboratory separates the appropriate sample fraction before measuring the substance.
Do I need to fast before this test?
Not always. Fasting or other preparation may be needed for some substances, so follow the specific instructions provided by your healthcare provider.
  1. 1
    MedlinePlus — Laboratory TestsSource
  2. 2
    Lab Tests OnlineSource
  3. 3
    Mayo Clinic — Tests & ProceduresSource

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.

Medical Disclaimer

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