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Alanine Aminotransferase and Aspartate Aminotransferase, Serum — Qualitative (Deprecated Test)

Published: August 9, 2026Updated: August 17, 2026

A qualitative serum test for two liver enzymes, ALT and AST, which may rise when liver cells are injured.

Quick summary

["This older qualitative test may indicate the presence of ALT and AST, but current quantitative liver tests usually provide more useful information."]

Medically reviewed by WellAlly Editorial TeamLast reviewed August 17, 2026Editorial policy

Key facts at a glance

LOINC
25307-0
Short code
Deprecated A alternata IgG RAST Ser Ql
Synonyms
Deprecated A alternata IgG RAST Ser Ql
Category
liver
Sample
serum
Container
Red-top tube (SST)
Units
N/A
Ref low
7
Ref high
56
Critical range
— – 500 N/A
Fasting
false
Population
adult
Sex
all
Age range
18–65 years
CPT
84484
SNOMED
302773008
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 test examines serum for alanine aminotransferase (ALT) and aspartate aminotransferase (AST), enzymes that are concentrated in liver cells. It is marked as deprecated, meaning it may no longer be routinely offered by laboratories.

Why might I need this test?

ALT and AST testing may be used to evaluate possible liver injury or disease. These enzymes can also rise for reasons unrelated to the liver, so results are interpreted with symptoms, medical history, and other laboratory tests.

How is the test performed?

A blood sample is collected, and the serum portion is tested for ALT and AST using a qualitative method. The slug does not specify the laboratory method, and the result is reported as detected or not detected rather than as a numeric enzyme level.

How do I prepare for the test?

No special preparation is usually required for a routine blood draw. Tell your clinician about medicines, alcohol use, recent illness, and any known liver problems because these factors can affect liver enzyme results.

Reference range

Adult males: 7-56 U/L; Adult females: 7-43 U/LN/A

Specimen: serum

No special preparation required. Avoid fatty meals before the test if possible.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

◆Associated findings1

Short name

ALT and AST, Serum — Qualitative

Frequently asked questions

What do ALT and AST measure?
ALT and AST are enzymes found in liver cells, with AST also present in several other organs. Their levels can increase when cells are damaged, but an enzyme result does not by itself diagnose a specific disease.
Why is this test marked as deprecated?
The test designation indicates that it is an older or discontinued test. The slug does not provide the reason, so ask the ordering clinician or laboratory whether a current quantitative ALT and AST panel is preferred.
Does a qualitative result show how high my liver enzymes are?
No. A qualitative result generally reports whether the enzyme was detected rather than providing a numeric concentration. Quantitative ALT and AST measurements are usually more useful for evaluating the degree of liver-cell injury.
  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 17, 2026. · Read our editorial policy