Alanine transaminase (ALT) blood test Information | Mount Sinai

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

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

Blood is drawn from a vein (venipuncture), usually from the inside of the elbow or the back of the hand. A needle is inserted into the vein, and the blood is collected in an air-tight vial or a syringe. Preparation may vary depending on the specific test.

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)

Risks

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)

Daniels L, Khalili M, Goldstein E, Bluth MH, Bowne WB, Pincus MR. Evaluation of liver function. In: McPherson RA, Pincus MR, eds. Henry’s Clinical Diagnosis and Management by Laboratory Methods. 24th ed. Philadelphia, PA: Elsevier; 2022:chap 22.

Pratt DS. Liver chemistry and function tests. In: Feldman M, Friedman LS, Brandt LJ, eds. Sleisenger and Fordtran’s Gastrointestinal and Liver Disease: Pathophysiology/Diagnosis/Management. 11th ed. Philadelphia, PA: Elsevier; 2021:chap 73.

Last reviewed on: 2/28/2023

Reviewed by: Jacob Berman, MD, MPH, Clinical Assistant Professor of Medicine, Division of General Internal Medicine, University of Washington School of Medicine, Seattle, WA. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.

What High ALT Levels Mean and How to Lower Them

High levels a liver enzyme known as ALT in the blood can indicate liver issues. Implementing these strategies may help lower ALT levels.

Alanine aminotransferase (ALT) is an enzyme found inside liver cells. Liver enzymes, including ALT, help your liver break down proteins to make them easier for your body to absorb.

When your liver is damaged or inflamed, it can release ALT into your bloodstream. This causes your ALT levels to rise. A high ALT level can indicate a liver problem, which is why doctors often use an ALT test when diagnosing liver conditions.

Several things can cause high ALT levels, including:

• nonalcoholic fatty liver disease (NAFLD)
• over-the-counter pain medications, especially acetaminophen
• prescription medications used to manage cholesterol
• alcohol consumption
• obesity
• hepatitis A, B, or C
• heart failure
• hereditary hemochromatosis, an inherited condition that can lead to liver disease due to iron overload
• thyroid disorders
• some muscle disorders
• celiac disease

Rare causes

Other causes of high ALT levels that are rare include:

• autoimmune hepatitis
• alpha-1 antitrypsin deficiency, an inherited condition that can lead to lung and liver disease
• Wilson’s disease, an inherited condition that can cause a buildup of copper in the body

Regardless of what’s causing your elevated ALT levels, it’s important to work with your doctor to find and address the underlying cause. But in the meantime, there are a few things you can try that may help lower your ALT levels.

Drink coffee

Several studies have found that coffee may have a protective effect on the liver and that drinking it can lower liver enzymes.

A 2017 review found that drinking anywhere from 1 to 4 cups of coffee per day can help lower ALT levels and reduce the risk of liver disease and cancer.

More recently, the results of a 2021 meta-analysis of 19 observational studies involving 222,067 people also suggested that coffee consumption was associated with lower ALT.

Another recent study into the benefits of coffee on liver health found that all types of coffee appeared to lower the risk of liver disease.

Here are 9 other science-backed benefits of drinking coffee.

Consume more folate or take folic acid

Consuming more folate-rich foods and adding a folic acid supplement to your diet are both linked to lower ALT levels.

While the terms “folate” and “folic acid” are often used interchangeably, they aren’t quite the same. They’re two different forms of vitamin B9.

Folate is a naturally occurring form of B9 found in certain foods. Folic acid is a synthetic form of B9 used in supplements and added to some processed foods. Your body processes them in different ways, too.

While they aren’t quite identical, both folate and folic acid have benefits when it comes to liver health and lowering ALT.

Studies have linked folate deficiency to increased ALT levels and liver damage and found that folic acid appears to reduce ALT in people with liver damage.

A 2017 study found that folic acid appeared to be just as effective as, if not more than, silymarin treatment in lowering liver enzymes in children with drug-induced liver injuries from antiepileptic therapy.

To help lower ALT levels, consider adding more folate-rich foods to your diet, such as:

• leafy greens, including kale and spinach
• asparagus
• legumes
• Brussels sprouts
• beets
• bananas
• papaya

You can also try taking a folic acid supplement. Most folic acid supplements contain doses of either 400 or 800 micrograms. Aim for a daily dose of 800 micrograms, which is the equivalent of 0.8 milligrams.

This is the dose involved in many studies looking at the link between folic acid and ALT levels.

Make changes to your diet

Adopting a healthier diet can help lower ALT levels and reduce your risk of liver disease.

A 2019 clinical trial compared the effects of a low sugar diet and a typical diet in adolescent boys with NAFLD. Sugar in the diet intervention group was limited to less than 3 percent of the total daily caloric intake.

After 8 weeks, those in the diet group had lower liver enzymes and a greater reduction in liver fat.

Reducing the amount of fat and carbohydrates can also help treat and prevent NAFLD, a common cause of high ALT.

To improve liver health and help lower ALT, you don’t necessarily need to make drastic changes to your diet. Start by trying to eat at least five servings of fresh fruits and vegetables per day.

You can also try incorporating these tips into your weekly meal planning:

• Limit fruits and vegetables served with high calorie sauces or added sugar and salt.
• Eat fish at least twice a week, ideally those high in omega-3 fatty acids, such as salmon or trout.
• Opt for fat free or low fat milk and dairy products.
• Replace saturated and trans fats with monounsaturated and polyunsaturated fats.
• Choose fiber-rich whole grains.
• Opt for lean animal proteins, such as skinless chicken or fish.
• Swap fried foods for baked or roasted ones.
• Snack on nuts, which have various health benefits and have been shown to lower liver enzymes in people with NAFLD.

Learn more about treating fatty liver disease with food.

There is no specific medical treatment for high ALT. Treatment, if any, depends on what’s causing the increase.

Of the 10 percent of people in the United States estimated to have high ALT, less than 5 percent have serious liver disease.

For most causes of high ALT, treatment involves lifestyle changes, such as exercise, a modified diet, and reducing alcohol intake.

Depending on the results of your liver panel and your medical history, your healthcare professional may recommend checking them again at a later date.

If they’re very high or if you have risk factors for liver disease or other symptoms, your doctor may recommend further testing or an appointment with a liver specialist to help diagnose the underlying cause of your high ALT.

Depending on what your healthcare professional suspects, they may recommend any of the following:

• blood tests to check for other conditions, such as hepatitis B and C as well as diabetes
• liver ultrasound
• abdominal CT scan
• biopsy
• thyroid stimulating hormone (TSH) test
• creatine kinase (CK) test
• lipid panel
• iron studies to rule out hereditary hemochromatosis

Contact a doctor if a blood test shows you have high ALT. Based on the results of your liver panel, the doctor will advise you on the next steps.

A high ALT level is usually a sign of some type of liver issue. It’s important to work with your doctor to find the underlying cause of your elevated ALT, even if you don’t have any symptoms.

Lowering your ALT will require treating the cause, but certain dietary changes can help.

what is it and how does its performance affect health? 1.1.1 What is ALT?

1. 8 How to reduce the level of Alt in the biochemical analysis of blood?

Alt is an enzyme found in human liver and heart cells. Its level in the blood is measured in a biochemical analysis, and an increase in this indicator may indicate problems with the liver or heart. In our article, you will find detailed information about what ALT is and how its level is related to human health.

Medical blood tests are one of the most effective ways to diagnose various diseases and disorders occurring in the body. One of the main indicators that allow you to determine the state of human health is ALT.

ALT is an alanine aminotransferase, an enzyme that is involved in the process of amino acid metabolism in the body. It is found in the tissues of the liver, heart, muscles and other tissues. When these tissues are destroyed, ALT enters the bloodstream, which makes it possible to determine the level of this enzyme by a biochemical blood test.

ALT levels affect the general condition of the body, so its level can be an indicator of various diseases, such as hepatitis, liver cirrhosis, heart attack, myopathy and other diseases. ALT can also increase with certain medications or as a result of increased exercise.

ALT in a biochemical blood test: definition and norms

What is ALT?

Alanine aminotransferase (ALT) is an enzyme found in liver cells and other organs, including the heart and muscles. When these organs are affected, ALT is released into the blood, which can be detected using a biochemical blood test. A high level of ALT in the blood can indicate the presence of diseases of the liver, heart and other organs.

ALT blood levels

Normal blood ALT values ​​differ by sex and age. ALT levels can also vary depending on the laboratory that performs the analysis. In general, the average normal range for adult men is 10 to 40 units per liter of blood, and for women, 7 to 35 units per liter of blood. ALT levels can be elevated in some diseases, such as hepatitis, cirrhosis, myocardial infarction, and other diseases.

Normal blood ALT levels by age Age group ALT norm, units/l

If ALT levels are higher than normal, this may indicate the presence of diseases of the liver, heart or other organs. However, a high ALT level does not always indicate a serious problem. For example, drinking alcohol, certain medications, and even exercise can temporarily increase blood levels of ALT.

What does an elevated level of Alt (alanine aminotransferase) mean in a biochemical blood test?

Alanine aminotransferase (ALT) is an enzyme found in body tissues, especially the liver and heart. An elevated ALT level in a biochemical blood test indicates damage or disease to these organs.

Manifestations of only a slight increase in ALT do not have specific symptoms, there may be a feeling of heaviness and pain in the right upper abdomen or slight discomfort. However, if you doubt your state of health, in any case, consult a doctor, he will tell you about further actions.

Normative values ​​of Alt level in the biochemical analysis of blood: Half Norm

Reasons for increasing Alt in biochemical analysis

Altastosis is a condition that is associated with elevated levels of ALT in a person’s blood. It is an indicator of the presence of pathological processes in the liver and other tissues of the body.

Increased levels of Alt in the blood can be observed in diseases such as:

• Hepatitis. This disorder is the most common cause of high blood ALT. Hepatitis A, B, and C are the most common types of hepatitis that cause elevated ALT levels.
• Cirrhosis of the liver. This disease is characterized by the replacement of hepatic tissue with connective tissue, which causes a decrease in liver function.
• Alcoholic liver disease. Long-term alcohol use can cause liver damage and increase Alt.
• Some drugs. Some medications can cause high levels of Alt in the blood.

If the level of Alt is elevated, this may indicate the presence of pathological processes in the body. It is necessary to consult a doctor to identify the causes and take measures to treat the disease.

How to determine the increase in the level of Alt in a biochemical blood test?

Alt is an enzyme found in liver cells and some other body tissues. When the cells are damaged, Alt is released from them into the blood, causing its increased concentration. Measurement of Alt levels is an important biochemical analysis that helps identify diseases of the liver and other organs.

Elevated levels of Alt in the blood can only be detected during a biochemical blood test. This process does not take much time and must take place in the laboratory. Most often, this analysis is prescribed by doctors for suspected liver disease. Your doctor may order the test again to check the results and to track the progress of your treatment.

1. It is important to be prepared for a blood test before taking it. Your doctor can give you specific instructions about what you can and can’t do before the test.
2. The blood test is usually done on an empty stomach. Before the analysis, it is necessary to refrain from eating and drinking for about 8-12 hours.
3. If you have a medical condition or are taking medication, tell the doctor who orders the blood test. Certain medications and medical conditions can affect the results of an ALT blood test.

A gastroenterologist will determine the indications for examinations, prescribe the necessary tests and interpret the results. You can trust him: he carries out diagnostics and treatment at the highest level.

Blood chemistry symptoms of elevated Alt

Alt is an enzyme found in liver cells and in small amounts in the heart, kidneys and pancreas. An elevated ALT level in a biochemical blood test may indicate various diseases.

• Jaundice – The symptom of jaundice may be associated with elevated levels of Alt in the blood. This is due to the fact that a high level of Alt indicates damage to liver cells, which can lead to disruption of its functions and the appearance of jaundice.
• Hepatitis – Elevated ALT levels may be associated with viral hepatitis, which is an infectious disease that affects the liver. Hepatitis can damage liver cells and increase blood levels of Alt.
• Cirrhosis of the liver – this severe disease is characterized by the replacement of healthy liver cells with scar tissue. An elevated Alt level is an indicator that liver cells are damaged and a consequence of cirrhosis.
• Pancreatitis – Elevated Alt together with elevated Amylase on a blood chemistry test may indicate pancreatitis. This is an inflammatory disease of the pancreas that can lead to tissue damage and elevated ALT levels.

If you suspect that you have elevated blood levels of Alt, be sure to visit your doctor for the correct diagnosis and treatment of the relevant conditions.

How is Alt level related to diseases of the liver and biliary tract?

Alanine aminotransferase (ALT) is an enzyme found in high concentrations in the liver and to a lesser extent in the heart, kidneys, and skeletal muscle. When the cells of these organs are damaged, Alt enters the bloodstream, as a result of which its level increases.

Alt levels are also associated with biliary tract diseases such as cholelithiasis, cholangitis and cholelithiasis. Changes in blood Alt levels can help identify inflammatory processes in the liver, such as steatosis (fatty degeneration) and alcoholic hepatitis.

It should be noted that elevated levels of Alt can be caused not only by diseases of the liver and biliary tract, but also by taking certain medications, intense physical exertion, injuries and operations. Therefore, it is important to consult a doctor and undergo additional tests to obtain an accurate diagnosis.

The role of Alt in the diagnosis of heart and muscle diseases

Alanine aminotransferase (Alt) is an enzyme that is a marker of damage to liver cells, but not only. A number of studies have shown that ALT is also involved in the diagnosis of certain diseases related to the heart and muscles.

High levels of Alt may indicate damage to the cardiovascular system, such as myocardial infarction or fibrosis of the heart muscle. Also, in patients with heart disease, an increase in serum ALT is usually observed. However, an increase in Alt often accompanies other blood biochemical parameters, such as AST and LDH.

Altogether, Alt can be a useful indicator of heart and muscle disease, but elevation is not 100% indicative of these diseases. For an accurate diagnosis, additional tests and examination by a doctor are necessary.

How to reduce the level of Alt in the biochemical analysis of blood?

A high level of Alt in a biochemical blood test may be a sign of a pathological process in the liver or another organ. Therefore, in order to reduce the level of Alt, it is necessary to conduct an examination and identify the cause of its increase.

If the doctor has given a recommendation to change the way of life, then it is necessary to follow it and lead a healthy lifestyle. Try to avoid alcohol, smoking, and fatty, fried, and salty foods. Include more fruits, vegetables, grains and proteins in your diet.

Medications can also be taken to help reduce ALT levels. But only after consulting a doctor, as some drugs can cause side effects and have contraindications.

In some cases, if the patient is diagnosed with liver disease, treatment with narrowly targeted drugs may be required. After the course of treatment, it is necessary to periodically undergo control studies to determine the level of ALT and evaluate the effectiveness of treatment.

How to act if the level of Alt in the blood is high

An increase in the level of Alt (alanine aminotransferase) in the blood can be a sign of various diseases of the liver, heart, pancreas and other organs. If you receive blood test results with elevated ALT levels, you should see your doctor for diagnosis and further treatment.

Your doctor may recommend the following steps to determine the cause of your elevated ALT levels:

• Additional blood and urine tests
• Ultrasound of the abdomen and heart
• CT or MRI of organs
• Biopsy of the liver or other affected organs drinking alcohol.

  It is important to remember that self-treatment of elevated ALT levels can be dangerous and lead to poor health.

  Alt and peculiarities of the use of certain drugs

  Alt and antibiotics

  Some antibiotics may cause an increase in Alt in the blood. This is due to toxic effects on the liver, which can lead to hepatitis or cirrhosis of the liver. Representatives of macrolide antibiotics, such as azithromycin and clarithromycin, can cause a similar effect.

  Alt and antivirals

  In the treatment of hepatitis C, drugs are sometimes used that can also increase the level of Alt in the blood. These are antiviral drugs such as Interferon alfa and Ribavirin. There is also a risk of liver toxicity when using ciprofloxacin.

  Alt and antifungal drugs

  Some antifungal drugs can increase blood levels of Alt. For example, fluconazole and itraconazole have a pronounced hepatotoxic effect. In this regard, when using them, it is necessary to control the level of Alt in the blood.

  Alt and analgesics

  Prolonged use of analgesics with acetaminophen may lead to an increase in the level of Alt in the blood. Taking paracetamol and other analgesics can cause dystrophic changes in the liver, which negatively affects the level of Alt.

  Alt and cholesterol-lowering drugs

  Statins are drugs used to lower blood cholesterol levels. However, with prolonged use of statins, an increase in the level of Alt in the blood is possible. This fact may indicate the development of hepatitis or the threat of the development of chronic liver diseases.

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  Q&A:

  What is ALT in a biochemical blood test?

  ALT (alanine aminotransferase) is an enzyme found in the cells of the liver and some other organs. When these cells are damaged, ALT enters the bloodstream, which can be determined in a biochemical blood test.

  What ALT values ​​are considered normal?

  The level of ALT in the blood depends on gender and age. In men, the norm is 10-40 units / l, in women – 7-35 units / l. But keep in mind that some drugs and diseases can affect the performance.

  What diseases can increase the level of ALT in the blood?

  Blood levels of ALT may be elevated in liver diseases such as hepatitis, cirrhosis, liver cancer, as well as heart disease, muscular dystrophy and other disorders of cellular metabolism.

  What does elevated blood ALT mean?

  Elevated levels of ALT in the blood indicate damage to the cells of the organs that contain this enzyme. The cause may be diseases of the liver, heart and other organs, as well as medication or alcohol.

  What to do with high blood ALT values?

  If the level of ALT in the blood is elevated, you should consult a doctor to clarify the cause. The doctor may prescribe additional tests to identify the disease, as well as recommendations for treatment and lifestyle changes.

  Can ALT levels be low?

  Yes, ALT levels may be below normal, but this is usually not a health problem. Low levels of ALT may be due to low activity of this enzyme, which can occur in acute or chronic liver failure or genetic disorders.

  ALT (AlAT, alanine aminotransferase)

  ALT is an enzyme from the group of aminotransferases that is responsible for amino acid metabolism and is produced intracellularly. Normally, the content of ALT in the blood is negligible, and the highest level of the enzyme is observed in the liver cells. Therefore, with an increase in the concentration of ALT in the blood, the first suspicion falls on asymptomatic lesions of this particular organ. As a rule, this analysis is necessary after a long-term use of medications, interaction with toxic substances (including alcohol), in the diagnosis of hepatitis, and suspicion of pancreatitis.

  An increase in ALT in the blood in a certain proportion with another enzyme, AST (aspartate aminotransferase), may also indicate a previous heart attack.

  Test results are highly affected by food intake, so it is important to strictly abstain for the 12 hours prior to blood sampling.

  ALT (alanine aminotransferase, ALAT) is an intracellular enzyme from the group of transferases, a subgroup of transaminases, which catalyzes the conversion of a-keto acids into amino acids by transferring amino groups. Normally, only a small part of this enzyme disappears into the blood. The enzyme is present mainly in the cytoplasm of hepatocytes, but it is also found in skeletal muscle and myocardial cells. The biochemical activity of ALT in the liver is almost 10 times higher than in the myocardium and skeletal muscles, therefore, an increase in the level of ALT in the blood is mainly considered as an indicator of damage to the liver parenchyma. When liver cells are damaged, the integrity of their membrane is violated and ALT enters the bloodstream. ALT has a greater diagnostic sensitivity in diseases of the hepatobiliary system than AST.

  If a biochemical analysis of ALT (ALAT) blood showed an increase in ALT activity by 50 times or more, then this can mainly be due to acute violation of hepatic perfusion, acute necrosis of liver cells caused by exotoxins, including paracetamol and carbon tetrachloride, viral hepatitis , infectious mononucleosis. An increase in the concentration of ALT in the blood is diagnostically significant, since its level increases even before the appearance of other clinical symptoms of liver diseases (jaundice, etc.). With viral hepatitis, an increase in enzyme activity occurs at a very early time – in the prodromal period (it is noted in 50% of patients – in 5 days, in 90% – 2 days before the clinical manifestation of the disease). High values ​​of ALT and AST are also observed in toxic hepatitis, especially in severe cases. A moderate increase in transaminases is observed with alcoholic liver damage. Depending on the stage of the cirrhotic process, the levels of ALT and AST can be either at the upper limit of normal, or at a 4-5-fold increase from the upper limit (the level of AST is higher than ALT). In patients with primary or metastatic liver carcinomas, an increase in transaminase activity by 5-10 times is observed, however, there are cases when their level remains within the normal range, mainly in the early stages of malignant infiltration of the organ. The level in the blood test ALT (ALAT), exceeding more than 15 times the upper limit of normal, is always an indicator of acute hepatocellular necrosis of toxic, viral or circulatory origin.

  An increase in the level in the analysis of ALT is also observed in myocardial infarction, since this enzyme is also found in the heart muscle, however, its increase compared to AST is insignificant, since the activity of ALT in cardiomyocytes, unlike AST, is low. In uncomplicated myocardial infarction, blood levels of ALT (ALAT) remain within the normal range or their slight increase is observed. An increase in serum ALT concentration in myocardial infarction may indicate the development of congestive phenomena in the liver.

  Indications for

  • Diagnosis of liver diseases.
  • Examination of contact persons in the focus of viral hepatitis.
  • Monitoring of patients with hepatitis of various etiologies.
  • Donor screening.

  Preparation for analysis

  • It is recommended to donate blood for research on an empty stomach, you can only drink water.
  • At least 8 hours must have elapsed since the last meal.
  • Blood sampling for research should be carried out before taking medications (if possible) or no earlier than 1-2 weeks after they are stopped. If it is impossible to cancel drugs in the direction for the study, it should be indicated which drugs the patient receives and in what doses.
  • The day before blood sampling, limit fatty and fried foods, do not take alcohol, exclude heavy physical exertion.
  • It is not recommended to donate blood for research immediately after radiography, fluorography, ultrasound – research, rectal examination or physiotherapy procedures.

  Factors affecting the results of the analysis

  • Hemolysis, chylosis tests, alcohol intake, treatment with hepatotoxic drugs (psychotropic drugs, anabolic steroids, contraceptives, salicylates, sulfonamides, antibiotics, immunosuppressants, anticancer drugs, drugs for chemotherapy and anesthesia).

  Prescribing physician

  General practitioner, surgeon, infectious disease specialist, endocrinologist, hematologist, internist, gastroenterologist.

  Attention! The interpretation of test results is for informational purposes, is not a diagnosis and does not replace the advice of a doctor. Reference values ​​may differ from those indicated depending on the equipment used, actual values ​​will be indicated on the results sheet.

  — Unit: U/L

  – Increase:

  • Necrosis of liver cells of any etiology (viral hepatitis, toxic liver damage).