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Alt lab test normal range: Liver function tests – Mayo Clinic

Alanine transaminase (ALT) blood test

Medical Tests 


The alanine transaminase (ALT) blood test measures the level of the enzyme ALT in the blood.

Alternative Names

SGPT; Serum glutamate pyruvate transaminase; Alanine transaminase; Alanine aminotransferase

How the Test is Performed

A blood sample is needed.

How to Prepare for the Test

No special preparation is needed.

How the Test will Feel

When the needle is inserted to draw blood, some people feel moderate pain. Others feel only a prick or stinging. Afterward, there may be some throbbing or a slight bruise. This soon goes away.

Why the Test is Performed

ALT is an enzyme found in a high level in the liver. An enzyme is a protein that causes a specific chemical change in the body.

Injury to the liver results in release of ALT into the blood.

This test is mainly done along with other tests (such as AST, ALP, and bilirubin) to diagnose and monitor liver disease.

Normal Results

The normal range is 4 to 36 U/L.

Normal value ranges may vary slightly among different laboratories. Some labs use different measurements or may test different samples. Talk to your health care provider about the meaning of your specific test results.

What Abnormal Results Mean

An increased ALT level is often a sign of liver disease. Liver disease is even more likely when the levels of substances checked by other liver blood tests have also increased.

An increased ALT level may be due to any of the following:

  • Scarring of the liver (cirrhosis)
  • Death of liver tissue
  • Swollen and inflamed liver (hepatitis)
  • Too much iron in the body (hemochromatosis)
  • Too much fat in the liver (fatty liver)
  • Lack of blood flow to the liver (liver ischemia)
  • Liver tumor or cancer
  • Use of drugs that are toxic to the liver
  • Mononucleosis (“mono”)
  • Swollen and inflamed pancreas (pancreatitis)


adam.com”>There is little risk involved with having your blood taken. Veins and arteries vary in size from one person to another and from one side of the body to the other. Taking blood from some people may be more difficult than from others.

Other risks associated with having blood drawn are slight, but may include:

  • Excessive bleeding
  • Fainting or feeling lightheaded
  • Multiple punctures to locate veins
  • Hematoma (blood collecting under the skin)
  • Infection (a slight risk any time the skin is broken)


Chernecky CC, Berger BJ. Alanine aminotransferase (ALT, alanine transaminase, SGPT) – serum. In: Chernecky CC, Berger BJ, eds. Laboratory Tests and Diagnostic Procedures. 6th ed. St Louis, MO: Elsevier Saunders; 2013:109-110.

Pincus MR, Tierno PM, Gleeson E, Bowne WB, Bluth MH. Evaluation of liver function. In: McPherson RA, Pincus MR, eds. Henry’s Clinical Diagnosis and Management by Laboratory Methods. 23rd ed. St Louis, MO: Elsevier; 2017:chap 21.

Pratt DS. Liver chemistry and function tests. In: Feldman M, Friedman LS, Brandt LJ, eds. Sleisenger and Fordtran’s Gastrointestinal and Liver Disease. 10th ed. Philadelphia, PA: Elsevier Saunders; 2016:chap 73.

Review Date: 01/26/2019

The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed physician should be consulted for diagnosis and treatment of any and all medical conditions. Call 911 for all medical emergencies. Links to other sites are provided for information only — they do not constitute endorsements of those other sites. Copyright ©2019 A.D.A.M., Inc., as modified by University of California San Francisco. Any duplication or distribution of the information contained herein is strictly prohibited.

Information developed by A.D.A.M., Inc. regarding tests and test results may not directly correspond with information provided by UCSF Health. Please discuss with your doctor any questions or concerns you may have.

Alanine Aminotransferase (ALT) Test and Results (aka SGPT Test)

Written by WebMD Editorial Contributors

  • Why Is ALT Important?
  • Why Would My Doctor Order This Test?
  • How Do I Prepare?
  • What Happens During the Test?
  • What Are the Risks?
  • What Do the Results Mean?
  • What Other Tests Will I Take?
  • More

The alanine aminotransferase (ALT) test is a blood test that checks for liver damage. Your doctor can use this test to find out if a disease, drug, or injury has damaged your liver.

Your liver does a lot of important things for you:

  • It makes a fluid called bile that helps your body digest food.
  • It removes waste products and other toxins from your blood.
  • It produces proteins and cholesterol.

Diseases such as hepatitis and cirrhosis can damage your liver and prevent it from doing its many jobs.

This enzyme is found mainly in your liver. Smaller amounts of ALT are in your muscle, kidneys , and other organs.

Your body uses ALT to break down food into energy. Normally, ALT levels in the blood are low. If your liver is damaged, it will release more ALT into your blood and levels will rise. (ALT used to be called serum glutamic-pyruvic transaminase, or SGPT).

Doctors often give the ALT test along with other liver tests.

Your doctor might recommend ALT if you have symptoms of liver disease or damage, such as:

  • Stomach pain or swelling
  • Nausea
  • Vomiting
  • Yellow skin or eyes (a condition called jaundice)
  • Weakness
  • Extreme tiredness (fatigue)
  • Dark-colored urine
  • Light-colored poop
  • Itchy skin

Here are some reasons you might get this test:

  • You’ve been exposed to the hepatitis virus.
  • You drink a lot of alcohol.
  • You have a family history of liver disease.
  • You take medicine that’s known to cause liver damage.

The ALT test can be done as part of a blood panel during a regular exam. If you’ve already been diagnosed with liver disease, your doctor can use the ALT test to see how well your treatment is working.

You don’t need any special preparation for the ALT test. Your doctor might ask you to stop eating or drinking a few hours before the test.

Tell your doctor what prescription drugs or supplements you take. Some medicines can affect the results of this test.

A nurse or lab tech will take a sample of your blood, usually from a vein in your arm. They will first tie a band around the upper part of your arm to make your vein fill with blood and swell up. Then they will clean the area with an antiseptic and place a needle into your vein. Your blood will collect into a vial or tube.

The blood test should take only a couple of minutes. After your blood is taken, the lab tech will remove the needle and band, then put a piece of gauze and a bandage over the spot the needle went in to stop the bleeding.

The ALT blood test is safe. Risks are usually minor, and can include:

  • Bleeding
  • Bruising
  • Infection
  • Slight pain when the needle is inserted
  • Fainting or feeling dizzy

You should get your results in about a day. A normal ALT test result can range from 7 to 55 units per liter (U/L), but it varies depending on the laboratory used. Levels are normally higher in men.

Slightly high ALT levels may be caused by:

  • Alcohol abuse
  • Cirrhosis (long-term damage and scarring of the liver)
  • Mononucleosis
  • Drugs such as statins, aspirin, and some sleep aids

Moderately high ALT levels may be because of:

  • Chronic (ongoing) liver disease
  • Alcohol abuse
  • Cirrhosis
  • Blockage of the bile ducts
  • Heart attack or heart failure (when your heart can’t pump enough blood to your body)
  • Kidney damage
  • Muscle injury
  • Damage to red blood cells
  • Heat stroke
  • Too much vitamin A

Very high ALT levels can be caused by:

  • Acute viral hepatitis
  • An overdose of drugs such as acetaminophen (Tylenol)
  • Liver cancer
  • Sepsis

ALT usually is done as part of a group of liver function tests called a liver panel.

This panel also includes an aspartate aminotransferase (AST) test. AST is another liver enzyme. As with ALT, the levels of AST in your blood rise if your liver is damaged.

Comparing ALT with AST levels gives your doctor more information about the health of your liver. The AST-to-ASL ratio can help your doctor figure out how severe the liver damage is and what might have caused it.

To find out what type of liver disease you have, your doctor might also test the levels of other enzymes and proteins found in your liver, including:

  • Albumin
  • Alkaline phosphatase
  • Bilirubin
  • Lactate dehydrogenase (LDH)
  • Total protein
  • GGT

Talk to your doctor to make sure you understand all of your liver test results. Also find out how these results might affect your treatment.

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Alt-test – ALT Linux Wiki

From ALT Linux Wiki

alt-test – ALT Linux testing framework based on Tapper.

The program is distributed under license GPLv3 .


 alt-test [options] [test1 ...]
Parameter Description
-l Show list of available test modules
-h Usage Help
-v Show full test progress
–version Software version

The tests are located in /usr/lib/alt-test.

Note: The test program comes with two tests: altlinux and selftest. The first one allows you to check if the current system is an ALT Linux distribution, the second one – to show you obviously fail tests


  • 1 Test start example
  • 2 Writing tests
    • 2.1 Example
    • 2.2 Checks
      • 2.2.1 Environment Variables
      • 2.2.2 Useful functions
    • 2.3 Universal check
    • 2. 4 Comments in the output
  • 3 Tips and secrets
    • 3.1 Stream Processing
 alt-test altlinux
alt-test -v selftest

The test file has a .t extension and is a shell script. It starts with an interpreter indication line:


Then the test functions are connected:

 . alt-test-functions

This is followed by one or more checks and the test description file ends with a function call



. alt-test-functions
test_file /etc/hosts
test_exec ls
test_package coreutils


Checks Description
test_file [] check if file exists
test_exec [] Check if an executable program exists and is available to run
test_package [] Check if a package is installed on the system or exists on disk. Package name can be specified with version and comparison sign since version 1.1.2. Example: test_package “samba>4.0.16”
test_unwished_package [] Check if the unwanted package is missing from the system or disk. since version 1.1.4

Environment variables

Variable Description
TEST_PACKAGE_SOURCE Path to file with ISO image, where to check for packages from version 1.1.2

Useful functions

Function Description
get_package_version Retrieve the version and release of a package installed or existing on disk since version 1.1.0

Universal test

ok $? ""

Comments in output

 append_comment "Comment"

Names of called files with tests are displayed in comments since version 1. 1.1.

Stream processing

Since test results are accumulated in the $TAP variable, avoid using subshell when streaming (for example, in pipelines):


 find /usr/share/applications -name \*.desktop | while read desktop_file; do
test_desktop_l10n "$desktop_file"


find /usr/share/applications -name \*.desktop > $out
while read -r desktop_file; do
test_desktop_l10n "$desktop_file"
done < $out
rm -f $out

ALT (ALT, Alanine aminotransferase, alanine transaminase, SGPT, Alanine aminotransferase)

Alanine aminotransferase (AlAT, ALT) is an intracellular enzyme, the content of which in the blood of healthy people is low. It is mainly found in the cells of the liver, myocardium, skeletal muscles, pancreas. When cells containing ALT are damaged or destroyed, the enzyme is released into the bloodstream, and its concentration in the blood increases.

Determination of the level of alanine aminotransferase is carried out for the diagnosis of liver diseases and dynamic monitoring of their treatment. The analysis is performed for suspected acute or chronic hepatitis of viral or toxic etiology, cirrhosis of the liver, primary tumors, or metastatic liver disease.

The growth of alanine aminotransferase in the blood in hepatitis is noted much earlier than the onset of the icteric stage, which makes it possible to identify the pathology at the initial stage.

As part of a screening examination (preventive examination of persons who do not have complaints) to assess the condition of the liver, before planned hospitalization and surgical treatment, an analysis for ALT is prescribed together with another enzyme - AsAT (aspartate aminotransferase).

The level of ALT together with other enzymes is evaluated in diseases of the pancreas and gallbladder - pancreatitis, cholecystitis, cholelithiasis; if there are complaints of unexplained general weakness, fatigue, yellowness of the skin and sclera, abdominal pain, including a feeling of heaviness in the right hypochondrium, nausea, vomiting.

In addition, the ALT level is taken into account in myocardial infarction and myocarditis, although in cases of heart damage it is only of secondary importance. The study is prescribed for suspected myositis, myodystrophy, when complaints of muscle pain cannot be explained by injuries or excessive physical activity.

Donation is a mandatory reason for testing for ALT.

ALT values ​​are assessed in any chronic disease, before prescribing drug therapy, for example, antitumor, anti-tuberculosis drugs, to assess the initial state of the liver and over time to assess drug tolerance.

Preparing for the procedure

It is better to take the test in the morning on an empty stomach (after an 8-14 hour break after the last meal).

Drinking water is allowed.

If necessary, it is permissible to donate blood 4-6 hours after a light meal.

On the eve it is desirable to avoid physical and emotional overload, overeating.

Avoid drinking alcohol 5-6 days before the test.

Avoid smoking 30 minutes before blood sampling.


The survey is completed within one business day.

What can affect the results

Intense physical activity the day before and even a few days before the test can lead to damage to muscle tissue (the so-called tear of muscle fibers) and, accordingly, an increase in the level of ALT. For the same reason, the analysis given after the injury is not informative.

Taking alcohol, certain drugs (antibiotics, non-steroidal anti-inflammatory drugs, anticancer drugs, oral contraceptives, etc.) often distort the result of the study. The list of medications taken should be discussed with the doctor who ordered the analysis, cancel those that are possible - without risk to health.

ALT (ALT, Alanine aminotransferase, alanine transaminase)

For research, blood is taken from a vein. Usually, ASAT (AST, Aspartate aminotransferase) is determined simultaneously and the ratio of ASAT / AlAT (de Ritis coefficient) is estimated.

You can take a blood test for ALT (ALT, Alanine aminotransferase, alanine transaminase) at the nearest INVITRO medical office. The list of offices where biomaterial is accepted for laboratory testing is presented in the "Addresses" section.

Interpretation of test results contains information for the attending physician and is not a diagnosis. The information in this section should not be used for self-diagnosis or self-treatment. An accurate diagnosis is made by the doctor, using both the results of this examination and the necessary information from other sources: history, results of other examinations, etc.


Units of measure: U/l.

Reference values ​​

Floor Age AlAT level, U/l
Both < 5 days < 49
5 days - 6 months < 56
6 - 12 months < 54
1 - 3 years < 33
3 years - 6 years < 29
6 - 12 years old < 39
Male 12 - 17 years old < 27
> 17 years old < 41
Female 12 - 17 years old < 24
> 17 years old < 31

Explanation of indicators

The level of ALT depends on the age and sex of the patient. Minor deviations from the norm, as a rule, do not require drug therapy, and the recommendations associated with them, such as rational nutrition, avoidance of alcohol, etc. should be discussed with your doctor.

The AST/ALAT ratio (de Ritis ratio) is normally between 0.91 and 1.75.

What do low readings mean

A significant decrease in the level of ALT can be detected in severe liver damage, for example, in the terminal stage of liver cirrhosis, when the number of liver cells is significantly reduced.

What do high rates mean

First of all, with an increase in ALT, liver problems should be suspected: fatty hepatosis, hepatitis of viral or toxic etiology, cirrhosis of the liver, liver cancer - primary or metastatic.

The degree of increase in ALT is usually associated with the extent or severity of liver damage, but cannot be considered as a determining factor for the prognosis of the disease. The maximum levels of ALT (and AST) - more than a hundred times higher than the norm, are observed in patients with acute viral and drug-induced hepatitis.

A significant increase in alanine aminotransferase can be observed in acute cholecystitis, cholelithiasis, and acute destructive pancreatitis. Another reason may be the use of hepatotoxic drugs that damage liver cells.

An increase in the level of ALT is detected with extensive injuries of the skeletal muscles, severe myositis and myodystrophy, frequent intramuscular injections.

A less significant increase in ALT is recorded in acute myocardial infarction and myocarditis.

Additional examination in case of deviation of the indicator from the norm

If a change (often an increase) in the level of ALT is detected, patients are consulted

general practitioners



, hepatologists, infectious disease specialists.

To clarify the diagnosis, in addition to ALT, other liver enzymes (AST, gamma-HT, alkaline phosphatase, bilirubin), clinical blood counts, and markers of viral hepatitis, primarily hepatitis B and hepatitis C, are usually examined.

An ultrasound examination of the abdominal organs is performed, according to indications - computed tomography (CT) with contrast.

If damage to the skeletal muscles is suspected, the CPK enzyme is additionally examined and a rheumatologist is consulted.

If a heart muscle disorder is suspected, a cardiologist should be consulted. Usually, the doctor prescribes additional electrocardiography (ECG), echocardiography, blood test for CF-CPK, troponin I.

The role of new reference values ​​of alanine aminotransferase in the diagnosis of various forms of non-alcoholic fatty liver disease in patients with metabolic syndrome. Journal of Biomedical Technologies № 1. 2015. P. 9-15.

  • Clinical guidelines "Cirrhosis and fibrosis of the liver". Developed by: Russian Society for the Study of the Liver, Russian Gastroenterological Association. – 2021.
  • Clinical guidelines "Liver cancer (hepatocellular)". Developed by: Association of Oncologists of Russia, Russian Society of Clinical Oncology, Russian Society of Radiologists and Radiologists.