About all

What causes enzymes to be elevated: Elevated liver enzymes Causes – Mayo Clinic


Elevated liver enzymes Causes – Mayo Clinic

Many diseases and conditions can contribute to elevated liver enzymes. Your doctor determines the cause by reviewing your medications, your signs and symptoms and, in some cases, other tests and procedures.

More common causes of elevated liver enzymes include:

  1. Over-the-counter pain medications, particularly acetaminophen (Tylenol, others)
  2. Certain prescription medications, including statin drugs used to control cholesterol
  3. Drinking alcohol
  4. Heart failure
  5. Hepatitis A
  6. Hepatitis B
  7. Hepatitis C
  8. Nonalcoholic fatty liver disease
  9. Obesity

Other possible causes of elevated liver enzymes include:

  1. Alcoholic hepatitis (severe liver inflammation caused by excessive alcohol consumption)
  2. Autoimmune hepatitis (liver inflammation caused by an autoimmune disorder)
  3. Celiac disease (small intestine damage caused by gluten)
  4. Cytomegalovirus (CMV) infection
  5. Epstein-Barr virus
  6. Hemochromatosis (too much iron stored in your body)
  7. Liver cancer
  8. Mononucleosis
  9. Polymyositis (inflammatory disease that causes muscle weakness)
  10. Sepsis (an overwhelming bloodstream infection that uses up neutrophils faster than they can be produced)
  11. Thyroid disorders
  12. Toxic hepatitis (liver inflammation caused by drugs or toxins)
  13. Wilson’s disease (too much copper stored in your body)

Causes shown here are commonly associated with this symptom. Work with your doctor or other health care professional for an accurate diagnosis.

  • Definition
  • When to see a doctor

March 05, 2020

Show references

  1. Friedman LS. Approach to the patient with abnormal liver and biochemical function tests. https://www.uptodate.com/contents/search. Accessed Jan. 17, 2020.
  2. Kwo PY, et al. ACG clinical guideline: Elevation of abnormal liver chemistries. American Journal of Gastroenterology. 2017; doi:10.1038/ajg.2016.517.
  3. Lab Tests Online. Liver panel. https://labtestsonline.org/tests/liver-panel. Accessed Jan. 17, 2020.


Why Too Many Patients Get Liver Tests They Don’t Need

It can start with the quick check of a box: A doctor orders a range of blood tests all at once, hoping to figure out what’s causing a patient to show signs of liver damage.

MORE FROM THE LAB: Subscribe to our weekly newsletter

It sounds harmless enough, not to mention quicker and more convenient than making the patient come back for more blood tests later.

But ordering too many liver tests at once may lead to unneeded worry, biopsies and costs, says a University of Michigan researcher who has studied the issue from many angles.

He and colleagues examine the issue of “over-testing” for liver conditions in two new papers published in the Journal of Hospital Medicine and the Journal of Hepatology. The new papers focus, respectively, on the 1 to 2 percent of all hospital patients who show very high levels of liver enzymes, and the 8 percent of clinic patients who have slightly high levels.

Both papers recommend that doctors should rule out common liver issues before testing for the uncommon ones. They also say that the modern computer systems doctors use to order liver tests should help them pause and make wiser choices.

It isn’t the initial $100 blood test for elevated liver enzymes that concerns Elliot Tapper, M.D., M.S. It’s the trend toward “one-stop shopping” testing, often ordered with the single click of a checkbox on a computer screen, that proceeds it.

“Physicians are legitimately thinking they’re doing the right thing by ordering the full panel of tests, being thorough and trying not to miss anything. In the hospital, they may be doing what a consulting liver specialist has suggested,” says Tapper, a gastroenterologist who treats liver diseases and conducts data-driven research on them at the U-M Institute for Healthcare Policy and Innovation.

“But they’re not aware of, or thinking about, the ramifications,” he continues. “This can include false positives for rare diseases that can cause the patient and their family anxiety and lead to unnecessary liver biopsies.”

Elevated liver enzymes – Drugs.com

  1. Mayo Clinic Symptom Guide
  2. Elevated liver enzymes
On this page

Medically reviewed by Drugs.com. Last updated on March 5, 2020.


Elevated liver enzymes often indicate inflammation or damage to cells in the liver. Inflamed or injured liver cells leak higher than normal amounts of certain chemicals, including liver enzymes, into the bloodstream, elevating liver enzymes on blood tests.

The elevated liver enzymes most commonly found are:

  • Alanine transaminase (ALT)
  • Aspartate transaminase (AST)
  • Alkaline phosphatase (ALP)
  • Gamma-glutamyl transpeptidase (GGT)

Elevated liver enzymes might be discovered during routine blood testing. In most cases, liver enzyme levels are only mildly and temporarily elevated. Most of the time, elevated liver enzymes don’t signal a chronic, serious liver problem.


Many diseases and conditions can contribute to elevated liver enzymes. Your doctor determines the cause by reviewing your medications, your signs and symptoms and, in some cases, other tests and procedures.

More common causes of elevated liver enzymes include:

  • Over-the-counter pain medications, particularly acetaminophen (Tylenol, others)
  • Certain prescription medications, including statin drugs used to control cholesterol
  • Drinking alcohol
  • Heart failure
  • Hepatitis A
  • Hepatitis B
  • Hepatitis C
  • Nonalcoholic fatty liver disease
  • Obesity

Other possible causes of elevated liver enzymes include:

  • Alcoholic hepatitis (severe liver inflammation caused by excessive alcohol consumption)
  • Autoimmune hepatitis (liver inflammation caused by an autoimmune disorder)
  • Celiac disease (small intestine damage caused by gluten)
  • Cytomegalovirus (CMV) infection
  • Epstein-Barr virus
  • Hemochromatosis (too much iron stored in your body)
  • Liver cancer
  • Mononucleosis
  • Polymyositis (inflammatory disease that causes muscle weakness)
  • Sepsis (an overwhelming bloodstream infection that uses up neutrophils faster than they can be produced)
  • Thyroid disorders
  • Toxic hepatitis (liver inflammation caused by drugs or toxins)
  • Wilson’s disease (too much copper stored in your body)

When to see a doctor

If a blood test reveals you have elevated liver enzymes, ask your doctor what the results might mean. Your doctor might suggest you undergo other tests and procedures to determine what’s causing your elevated liver enzymes.

© 1998-2019 Mayo Foundation for Medical Education and Research (MFMER). All rights reserved.
Terms of use.

Hepatitis and elevated liver enzymes explained

July 28 is World Hepatitis Day, an occasion to raise awareness about the World Health Organization’s goal to eliminate hepatitis. But first, we need to understand what triggers the condition. When a doctor uses the term “hepatitis,” it means that there is inflammation in the liver leading to an elevation in liver enzymes. Hepatitis ranges from limited, benign elevations to significant diseases that need to be evaluated and treated. Reshi Kanuru, MD, PPG – Gastroenterology, helps us better understand the disease and its causes.

alcohol and medications as the cause.
Most commonly, elevated liver enzymes are related to excessive alcohol use or the use of certain medications. While it’s likely that a few alcoholic drinks per week won’t cause an elevation in liver enzymes, the amount of alcohol that can cause liver damage varies from person to person. Alcohol consumption in any form can put a strain on the liver, and your doctor can help determine if it’s the cause of your hepatitis. Additionally, numerous medications, such as antibiotics, blood pressure medications, and cholesterol medications can also put a strain on the liver and cause elevations in the enzymes. The good news is that stopping the use of these medications, or stopping the consumption of alcohol, will allow the hepatitis to resolve over time and your enzymes will eventually return to normal.

viral hepatitis.
The next most common cause of liver enzyme elevations is viral hepatitis, such as hepatitis A, B, or C. Of these three types, hepatitis A, which is contracted through contaminated food, is the only one that does not cause long term liver injury. Hepatitis B and C can both lead to long term liver injury and eventually cirrhosis, which is severe scarring of the liver. Currently, hepatitis C is behind most needed liver transplants in the United States. Because hepatitis C is so common and can cause such severe damage, it’s recommended that anyone born between 1945 and 1965 be screened for the disease. It’s important to understand that both hepatitis B and C are treatable.

In the past, hepatitis C was difficult to treat and had poor cure rates partly because of medications that had many intolerable side effects. Recently, however, new medications for hepatitis C have been developed that have few side effects, and boast cure rates above 95 percent after a single course of treatment. Treating everyone for hepatitis C will prevent cirrhosis in millions of Americans and help to significantly reduce healthcare costs in the future.

fatty liver disease.
The epidemic of obesity and the availability of fried foods have led to dramatic health consequences.  Instances of both heart disease and fatty liver disease have been increasing over the last few decades, primarily because of our poor eating habits and overall weight gain.

Fatty liver disease is when fat deposits in the liver and leads to inflammation, which can cause an elevation in liver enzymes. Typically, fatty liver disease occurs in those dealing with obesity who may also have diabetes; however, the disease can also occur in thin individuals who may have genetics that predispose them to liver issues. It’s important to catch fatty liver disease as early as possible, not only because it will soon beat hepatitis C as the most common cause for liver transplantation in the United States, but also because fatty liver disease significantly increases the risk of death due to heart attack and stroke. It can lead to cirrhosis of the liver.

The treatment of fatty liver disease entails eating healthy and committing to 30 minutes of cardiovascular exercise every day with the goal of losing 10 percent of your body weight. Losing weight will cause the amount of fat deposited in the liver to significantly decrease and your risk of heart attack, stroke, and cirrhosis will greatly improve.

autoimmune hepatitis, PBC, PSC and other liver disorders.
Though most people will develop hepatitis related to alcohol, medications, fatty liver and viruses, there are many other diseases that cause elevations in liver enzymes.  Our immune system plays a large role in our health, but unfortunately, the immune system can also cause diseases.

Diseases like autoimmune hepatitis, primary sclerosing cholangitis and primary biliary cholangitis are all autoimmune disorders that affect the liver. It is important to be evaluated for these diseases because they can cause severe liver injury. Beyond autoimmune issues, there are liver diseases that cause abnormal deposition of copper and iron in the liver.  These deposition diseases not only cause liver injury, but can cause damage to multiple organs throughout the body.




Normal Range, High vs Low

A cardiac enzyme test is one tool doctors use to see if you’re having — or already had — a heart attack. You might also get the test if you have symptoms of a blockage in your heart’s arteries such as:

Severe stress on the heart can damage its muscle. When that happens, your heart releases certain enzymes — a kind of protein — into your blood. 

After a heart attack, the level of these enzymes can get pretty high. So checking them is a good way for your doctor to know something serious is going on.

A cardiac enzyme test does just that. Your doctor might want to measure your enzymes to figure out what’s happening with your heart.

Your doctor will most likely test for an enzyme called troponin. It goes into your blood soon after a heart attack. It stays at high levels even after other enzymes have gone back to normal.

What Happens During the Test?

It’s a lot like any other blood test.

Your doctor uses a thin needle to take a small amount of blood, most likely from your arm near your elbow. You’ll feel a pinch or sting when the needle goes in, but that’s usually all.

It only takes a few minutes. You can get your results quickly since these tests usually are urgent. Your doctor may do the same enzyme tests over time to see how your levels change.

What Do the Results Mean?

The cardiac enzyme test gives you a number measured in nanograms per milliliter (ng/ml). This tells your doctor how much of the enzyme is in your blood.

It can find even very small amounts. It takes 1 billion nanograms to make just 1 gram.

Labs test for enzymes in different ways, so what’s normal depends on where you had the test done. Your doctor can help you understand what your numbers mean. They’ll also give you a physical exam and look at other test results to get the full picture of what’s happened.

lf you had a heart attack, your doctor will talk to you about next steps, such as treatments, follow-up care, medicine, and lifestyle changes such as diet, exercise, and how to handle stress.

Symptoms, Causes, Diagnosis, and Treatment

Transaminitis refers to elevated levels of certain liver enzymes, called transaminases, that are detected via a blood test. It isn’t a medical condition, but an outcome on a laboratory test that usually needs further medical investigation. Elevated transaminase enzymes might be a sign of liver disease or another medical condition. Transaminase elevation, elevated liver enzymes, and hypertransaminasemia are other terms sometimes referring to the same thing.

In the general population, the number of people with elevated levels might be 10% or higher. However, only 5% or less of these individuals have a serious problem with their liver.

Verywell / Gary Ferster 


Elevated transaminase enzymes may be an indicator of medical conditions that can cause certain symptoms. These might include:

  • Fatigue
  • Itchy skin
  • Yellowed skin (jaundice)
  • Abdominal pain or swelling
  • Swelling in the legs and ankles
  • Nausea or vomiting
  • Excess bleeding from poor blood clotting

However, in many cases, people have elevated transaminase enzymes without having any symptoms. This may be especially likely if the elevations in these enzymes are not severe.

Liver Function

To understand what causes elevated transaminases and why they might be a concern, it is helpful to understand a little about the liver. Your liver is an organ that serves a variety of functions, including breaking down parts of some nutrients and removing certain toxins and metabolic byproducts.

It also plays important roles in making certain proteins, including ones used for blood clotting and for fluid management in the body.

Damage to the liver can cause many different symptoms and problems.


Transaminases are a type of enzyme important for the synthesis of amino acids (the building blocks of protein). They are also called aminotransferases. Usually, the term “transaminase” is used to refer to one of two specific enzymes: aspartate transaminase (AST) or alanine transaminase (ALT).

These enzymes can be found in the liver, but also to a lesser extent in other organs, such as the skeletal muscles, heart, and kidneys (particularly AST). 

Liver Disease

A number of different medical conditions can cause minor or major liver damage. This causes the release of AST and ALT into the bloodstream, causing elevated levels to show up on blood tests. Some of these potential causes include nonalcoholic fatty liver disease (NAFLD), alcoholic liver disease, liver infection (such as from hepatitis B or C), autoimmune disorders (like autoimmune hepatitis or primary biliary cholangitis), and rare genetic diseases like Wilson’s disease, hereditary hemochromatosis, or alpha-1 antitrypsin deficiency.

NAFLD is associated with metabolic syndrome, elevated triglycerides, low HDL cholesterol, high blood pressure, increased waist circumference, obesity, and insulin resistance (such as in pre-diabetes or type 2 diabetes).

Liver Problems From Medications

Transaminases might also be elevated as a reaction to certain medications. This might be particularly likely if a person is taking more than one medication that might damage the liver. Some common medications that sometimes cause elevations in transaminases include blood pressure medications statin drugs (atorvastatin), and medications for autoimmune disease (methotrexate).

Pain relievers (acetaminophen or aspirin), antidepressants (bupropion), drugs for acid reflux (omeprazole), and various over-the-counter herbal products can also result in an elevated reaction.

Diseases of Other Systems

Medical conditions that affect other parts of the body can also sometimes cause elevated transaminases. (This is particularly true of elevations of AST as opposed to ALT). Some of these problems include:

  • Thyroid disorders
  • Celiac disease
  • Abnormal breakdown of red blood cells (hemolysis)
  • Certain muscle disorders (like polymyositis)


Elevated levels of transaminases are found from blood tests for ALT and AST. If your AST and ALT are elevated, you might be told that you have transaminitis. You also might be told that you have elevated liver function tests (LFTs). Liver function tests include not just AST and ALT, but other tests such as albumin and bilirubin, and alkaline phosphatase.

These can give other information about how the liver and other organs might be functioning. These tests are often performed as part of the medical diagnosis for a number of different problems. Sometimes, people learn that they have elevated liver enzymes even when they haven’t noticed troublesome symptoms.

If you have elevated transaminases, your clinician will want to contextualize this with your overall health. The ratio of AST and ALT can give an indication of what type of problem might be going on. The amount of elevation is also an important diagnostic clue. For example, very high levels of transaminases likely indicate more severe, recent liver damage.

Medical history and exams are also important to consider. These can help your clinician gain clues about the potential causes of your elevated transaminases. For example, it’s important that your clinician ask you about your alcohol intake and your medications. Your clinician will also examine you for any signs of liver disease (or that of other organ systems).

Additional medical tests may also be needed. Depending on the situation, these might include additional liver function blood tests, INR (International normalized ratio) blood test, a complete blood count (CBC), iron and hepatitis tests, as well as tests for triglycerides, total cholesterol, a glucose A1C test, and/or additional tests for non-liver causes (like thyroid tests).

If transaminase levels don’t go down with treatment, follow up tests might be needed. These might include:

  • Ultrasound of the liver
  • Liver biopsy

In difficult-to-diagnosis situations, a referral to a gastroenterologist may be helpful.

Diagnosis Caveats

Elevated transaminases are not always a good indicator of how well the liver is functioning. With mild increases, there might be damage to the liver, but not enough to impair its functions. Also, increases in transaminases (particularly AST) can sometimes be caused by other kinds of medical problems.

Additionally, sometimes people may have severe liver damage but not necessarily elevated transaminases. High levels of AST and ALT usually indicate significant ongoing damage to the liver. But a person with severe liver disease might have had previous damage to the liver without showing a currently elevated AST or ALT. In this case, other tests can help fill out the clinical picture.


Elevated transaminases may indicate that you need treatment of some sort. This will depend on the underlying cause and its severity. People with symptoms of liver disease along with elevated transaminases may need more prompt interventions.

For example, if your clinician suspects nonalcoholic fatty liver disease, lifestyle interventions are usually the first recommended treatment. This might include losing weight, avoiding foods that contain fructose, engaging in rigorous physical exercise, and limiting alcohol intake. Depending on the situation, other treatments might include antiviral treatments for viral hepatitis or stopping a drug causing liver damage.

You may need repeat AST, ALT, and other liver function tests after you start your treatment. This can help show how well you are responding to the treatment. Sometimes these tests reveal that mildly elevated levels of transaminases have gone down, even without treatment.

Taking Steps to Stop Liver Disease

If you do have a type of liver disease, it’s important to halt the progression of liver damage. Even if you don’t have symptoms now, your liver might be becoming gradually more damaged over time.

Eventually, this might cause life-threatening liver failure. Taking steps now may help you prevent long-term problems.

A Word From Verywell

You might be alarmed if you’ve been told you have transaminitis or elevated liver tests. It might be especially surprising if you had no idea that your liver could be at risk. However, try not to panic. Your doctor will probably need to find out more to let you know what is going on. In most cases, your clinician will be able to work with you to help protect your liver and your future health. Don’t hesitate to ask if you have any questions about possible diagnosis or treatment.  

Enzyme Blood Level – an overview

D Experimentally Induced Liver and Muscle Disease

Plasma enzyme profiles after experimentally or spontaneously occurring liver disease have been studied in a number of avian species. The results of studies in racing pigeons (Lumeij et al., 1988a, 1988b) with two different types of liver disease were compared to plasma chemistry changes after muscle injury. Liver disease was induced by ethylene glycol or D-galactosamine, and muscle injury was induced by an intramuscular injection of doxycycline in three groups of six pigeons each. Plasma chemical changes were correlated with histological findings from organ samples taken just after the last blood collection (Fig. 28-16, Table 28-2).

Table 28-2. Summary of Specificity and Sensitivity of Plasma Chemical Variables in Liver and Muscle Disease Based on Experimental Studies in Pigeons by ]Lumeij et al. (1988a, 1988b)

VariableLiver diseaseMuscle disease
Bile acids++++++

Plasma AST activity and bile acid (BA) concentration were the most sensitive indicators of liver disease in the racing pigeon, followed by ALT, GGT, and LD. Although all pigeons with histological proven ethylene glycol- or galactosamine-induced liver damage had increased AST activity and BA concentrations in their plasmas, these constituents were not raised at every sampling time. Increased plasma GLDH activities were associated with large necrotic areas in the liver. Moderate necrosis of liver cells resulted in slightly elevated GLDH activities. Degeneration of liver cells and hepatitis with single-cell necrosis did not give rise to elevated plasma GLDH activities. Plasma CK activity was never increased because of liver damage, whereas GLDH, GGT, and BA were never elevated during muscle damage. Thus, these four constituents are useful for differentiating between liver and muscle disease. GLDH is the most liver-specific enzyme in the racing pigeon. Because GLDH is localized within the mitochondria of the liver cells, increased plasma GLDH activities, however, are only observed after liver cell necrosis.

The enzymes that are the most specific indicators of muscle and liver cell damage (CK and GLDH, respectively) have shorter half-lives than AST and ALT, which are not specific indicators of damage to either organ. Thus, after muscle or liver cell damage, AST and ALT activities in plasma can be increased, even though CK or GLDH activities have returned to baseline values. The fact that LDH has a shorter half-life than CK makes this enzyme valuable for differentiating between muscle and liver disease in the pigeon. When plasma LDH activity is increased in the absence of elevated CK activity, muscle damage is unlikely. Enzyme profiles can only serve as rough guides to interpretation of elevated plasma enzyme activity and are not characteristic for a particular organ. The most important reason is that the enzyme profile alters after enzymes have entered the circulation resulting from different removal rates for the various components.

Based on the tissue enzyme studies, it seemed that LD was the most sensitive indicator of liver cell damage, whereas ALT, because of its low activity in liver, would be of limited value. It also seemed that LDH would be a more sensitive indicator of muscle cell damage than ALT. Experimentally induced liver and muscle damage, however, demonstrated that ALT activity in plasma is increased sooner than LDH activity. The relative increase of ALT was also larger than that of LDH, except in severe liver cell damage accompanied by large areas of necrosis. Plasma ALT activities were increased for a longer period after organ damage compared to LDH. These findings can be explained by differences between their clearance half-lives. The clearance half-life of LDH is 15 to 30 times less than that of ALT.

Campbell (1986) reported increased AST and ALT activities in 75% of pigeons with aflatoxin B1-induced liver damage and increased LDH activities in 33%. In addition, AP and GGT were not sensitive indicators of liver disease in pigeons, cockatiels, red-tailed hawks, and great horned owls. With the exception of GGT, these findings were confirmed by Lumeij et al. (1988a, 1988b). The discrepancy might reflect the difference in the hepatotoxic agents used. In the study of Lumeij et al. (1988a, 1988b), GGT activities were increased in the majority of pigeons with experimentally induced liver disease, though no GGT activity could be detected in supernatants of liver tissue homogenates. This might be explained by synthesis of GGT during (cholestatic) liver diseases, as has been reported in mammalian species (Kaplan and Righetti, 1969; Kryszewski et al., 1973). Phalen et al. (1997) found that 5/5 Amazon parrots with bile duct carcinoma showed increased GGT activities and suggested that GGT may prove a valuable tool for early detection and staging of bile duct carcinomas.

In birds, increased AP activities are predominantly associated with increased osteoblastic activity, such as skeletal growth, nutritional secondary hyperparathyroidism, rickets, fracture repair osteomyelitis, as well as impending ovulation (Lumeij and Westerhof, 1987) (see Section VIII.E). Increased plasma AP associated with liver disease in birds is rare (Ahmed et al. , 1974). In the experimental studies from Lumeij et al. (1988a, 1988b), AP and CK were never elevated after liver cell damage, whereas activities of these enzymes in liver tissue were negligible. Increased activities of liver enzymes in plasma may indicate recent damage to liver cells but do not give information on liver function. In end-stage liver disease (cirrhosis), it is possible to have normal activities of liver enzymes in the plasma, because active damage to liver cells has ceased (e.g., Fig. 28-11).

In psittacine birds, the use of a good anamnesis and plasma AST is sufficient to make a tentative diagnosis of liver disease. When birds are known to have been recently injected intramuscularly, elevated AST (and ALT) activity should be interpreted with caution. Including a plasma constituent that specifically gives information on liver function, for example, total bile acids, has proven to be of great value. When liver disease is suspected, a biopsy of this organ is essential to establish a definite diagnosis.


Enzymes – specific proteins that play the role of biological catalysts in the body. Enzymes are found in all cells of the body, where their concentration is much higher than in blood plasma.

Normal levels of enzyme activity in serum reflect the relationship between biosynthesis and release of enzymes, as well as their clearance from the bloodstream.

The study of the level of enzymes in clinical practice is used to solve the following problems:

  1. establishing a diagnosis;
  2. carrying out differential diagnostics;
  3. assessment of the dynamics of the course of the disease;
  4. Determination of the effectiveness of treatment and the degree of recovery.

In the Clinical Diagnostic Laboratory, the serum activity of the following enzymes is determined:


Amylase is an enzyme that breaks down polysaccharides. The pancreas and salivary glands are the richest in this enzyme. Determination of amylase activity is important in the diagnosis of pancreatic diseases.

An increase in serum amylase activity by 2 or more times should be regarded as a symptom of pancreatic damage.More informative about the function of the pancreas is the determination of amylase activity in urine.

Amylase pancreatic

Pancreatic amylase is a biologically active substance involved in the metabolism of carbohydrates. In the human body, most of it is produced by the pancreas.

In the case of a disease of the pancreas or blockage of the duct between it and the duodenum, pancreatic amylase begins to be released into the blood, indicating that there is significant trouble in the state of this important digestive organ.


Lipase is a water-soluble enzyme that catalyzes the hydrolysis of insoluble ester-lipid substrates, helping to digest, dissolve and fractionate fats.

Lipase, together with bile, breaks down fats and fatty acids, as well as fat-soluble vitamins A, D, E, K, converting them into heat production energy.

AST – aspartate aminotransferase

AST – aspartate aminotransferase – an enzyme widely distributed in human tissues (heart, liver, skeletal muscles, kidneys, lungs, etc.)etc.).

The activity of AST in the blood increases with a number of diseases, especially with damage to organs and tissues rich in this enzyme.

The most dramatic changes in AST activity are observed with damage to the heart muscle. AST is also elevated in acute hepatitis and other severe liver cell damage.

ALT – alanine aminotransferase

ALT – alanine aminotransferase – an enzyme found in skeletal muscles, liver, heart. In the myocardium, it is significantly less than AST.The highest concentrations of ALT are found in the liver.

In clinical practice, the simultaneous determination of the activity of AST and ALT in the blood is widely used; it carries much more information about the localization and depth of the lesion, the activity of the pathological process; allows you to predict the outcome of the disease.

ALP – Alkaline phosphatase

ALP – alkaline phosphatase – is widespread in human tissues, especially in the intestinal mucosa, osteoblasts, the walls of the bile ducts of the liver.An increase in alkaline phosphatase activity accompanies rickets of any etiology, bone changes associated with hyperparathyroidism.

The enzyme activity grows rapidly in osteosarcoma, cancer metastases in the bone, myeloma, lymphogranulomatosis with bone damage.

A significant increase in alkaline phosphatase activity is observed in cholestasis. Its increase is observed in 90% of patients with primary liver cancer and with liver metastases. Its activity sharply increases in case of alcohol poisoning against the background of chronic alcoholism.It can increase with medications showing a hepatotoxic effect.

GGT – gamma glutamyl transpeptidase

GGT – gamma-glutamyl transpeptidase – found in the liver, pancreas, kidneys.

In other fabrics – in small quantities. The change in its activity in the serum is of great diagnostic value in diseases of the liver and hepatobiliary tract. This enzyme is more sensitive to abnormalities in liver cells than ALT, AST, ALP, etc.d.

LDH – total lactate dehydrogenase.

LDH – total lactate dehydrogenase – the highest activity was found in the kidneys, myocardium, skeletal muscles and liver. Under physiological conditions, increased LDH activity is observed in pregnant women, in persons after intense physical activity.

Of the pathological conditions, an increase in LDH activity causes myocardial infarction, congestion in the liver, pulmonary infarction, myopathy, liver carcinoma or cancer metastases in the liver, megaloblastic and hemolytic anemia, acute and exacerbation of chronic kidney disease.

decoding, norm, which means an increase in the level of AsAT

A biochemical blood test for AST is widespread in clinical practice and is used to diagnose a variety of diseases. This study is used by a wide variety of specialists, including cardiologists, therapists and gastroenterologists. The reason for this demand is its informativeness and versatility regarding pathological changes in tissues and organs.The AST test is specific for damage to the heart muscle, hepatitis of all types, malignant lesions of the bone tissue, etc. As a rule, it is used in combination with blood tests for ALAT *.
AlAt is a biochemical blood test that accompanies the diagnosis of liver diseases. It is used as an independent study and in combination with AST.

AsAT and ALT

Tests for AST and ALT are two studies, often prescribed by a doctor in combination.Why is the level of these two enzymes so important to determine simultaneously? For the first time, the idea of ​​the informativeness of their ratio was put forward by the scientist Fernando De Ritis from Italy. He used the method for the differential diagnosis of various types of hepatitis. Since then, his name has become a household name. The Ritis coefficient shows the ratio of the activity of AST and ALT. In healthy people, the coefficient is 0.91-1.75. The indicator is informative only if the values ​​of these enzymes exceed the reference values.
If in the double test only the AST values ​​are exceeded, this means that the myocardium is damaged.With damage to the heart muscle, the level of AST increases 8-10 times, ALT – only 1.5-2 times.
If the patient has a liver problem, on the contrary, the ALT level increases 8-10 times, and the AST values ​​- only 2-4 times.

What is an enzyme

AST or AST is a protein synthesized inside the cells of the human body. Its highest concentrations are found in the tissues of the myocardium, muscles and liver. To a lesser extent, the enzyme is present in the kidneys, pancreas, cells of the central nervous system and the brain.It is encoded by the genes GOT 1 and GOT 2. In a healthy person, the level of the enzyme is quite low. Its active release into the blood begins with a rupture of the heart muscle, as well as destruction of the liver as a result of hepatitis, cirrhosis or cancer. The enzyme is important because it contains vitamin B 6, which is involved in amino acid metabolism and, accordingly, insulin synthesis. In analyzes, the indicator is measured in units per liter of blood.

Spectrum of application of the analysis on AST

  • In cardiology as a marker of myocardial infarction.In the heart muscle, the enzyme is more than 10,000 times active than in the blood. With a heart attack, an intense release of the enzyme occurs.
  • For liver pathologies. Diseases such as hepatitis and cirrhosis are certainly accompanied by the destruction of liver tissue and a sharp jump in AST values.
  • For chronic alcoholism.
  • In obstetrics and gynecology. During pregnancy, a woman may experience a slight increase in AST values. This is due to the effects of the growing fetus on the mother’s liver.In the first trimester, its values ​​should not exceed 31 U / L, in the second and third – 30 U / L.
  • In endocrinology for diabetes mellitus and / or overweight.

Symptoms for which an AST test is recommended

  • Skin yellowness
  • Yellowness of the eye sclera
  • Pain in the right and left hypochondrium
  • Dyspeptic disorders (vomiting, nausea, heartburn)
  • General decrease in appetite and food cravings
  • Abnormalities in the results of urine and feces
  • Itching

How to Prepare for Analysis

To improve the reliability of your analysis, some rules and restrictions should be followed.So, on the eve of the study, one should refrain from eating fatty and smoked foods, as well as confectionery. It is best if the test is performed on an empty stomach in the morning. When taking medications, you need to consult with your doctor about their possible cancellation. The fact is that with a biochemical blood test, many medicines can affect the results of the study. When treated with antidepressants, antibiotics, diuretics and other drugs, the test readings may be distorted.In addition, it is forbidden to perform ultrasound, X-ray examination and physiotherapy procedures immediately before visiting the treatment room.

Explanation of the analysis for ASAT

Norm for women

AST test values ​​differ depending on age and gender. So in women, the norm of the enzyme in the blood is 31 U / l. The older a person is, the lower his activity in the body. This is due to a slowdown in metabolism in general. A natural physiological condition such as pregnancy also affects enzyme levels.During this period, its small jumps can be observed both in one direction and in the other direction.

Norm in men

The concentration of the enzyme in men begins to exceed that in women from 12-17 years of age. Its higher concentrations are due to the large volume of muscle tissue. At puberty, the norm of AST in boys is about 29 U / L. This is about four units higher than that of girls of the same age. In an adult man, the enzyme level can reach 37 U / L.

Deviations from the norms

An excess of AST in the blood can occur for the following reasons:

Heart muscle rupture (myocardial infarction)

Malignant liver damage

Metastases of malignant tumors to the liver

Alcohol abuse

Autoimmune diseases of muscle tissue

Poisoning, including alcohol, drugs and poisonous mushrooms

Injuries, fractures

Malignant bone lesions

Heat or sunstroke

If high AST values ​​persist for several days, this means that the patient is in serious condition.An increase in the growth of values ​​indicates that the tissues in the focus of pathology have become necrotic and additional rehabilitation measures need to be urgently taken.

A decrease in the AST level is observed when:

  • Blood manipulation (hemodialysis)
  • Vitamin B deficiency
  • Liver necrosis
  • Pregnancy

forget that only the attending physician can interpret the values.The reason for the deviations in the readings of the blood test for AST
there may be not only diseases, but also other factors, such as use
Supplements and treatment with medications. Results can be
unsatisfactory due to diseases of the heart, liver or other organs.
studies including a test for bilirubin, total protein and ALT. Specialist
will compare all the data with the results, and then make the appropriate

(11 assessments, average 4.55 out of 5)

Read also

90,000 Increased GGTP – Gamma-glutamyl transpeptidase in liver diseases – tests in liver diseases

Gamma glutamyl transferase (gamma glutamyl transpeptidase) catalyzes the transfer of gamma glutamyl to an amino acid or peptide.GGTP is a membrane-bound enzyme.

Changes in serum GGTP activity are of great diagnostic value in diseases of the liver and hepato-biliary tract. This enzyme is more sensitive to abnormalities in liver cells than ALT, AST, alkaline phosphatase.

GGTP is polysemantic in terms of diagnostics. At least 5 processes cause an increase in its activity in the blood:

– fatty degeneration of the liver – Fatty hepatosis

– necrosis of hepatic cells;

– violation of the outflow of bile – cholestasis;

– alcohol intoxication;

– tumor growth in the liver;

– medicinal damage to the liver.

This etiological variety of mechanisms for increasing GGTP requires a very careful and careful assessment of the causes of this hyperenzymemia. The detection of high activity of GGTP makes us look for the reason for this increase. As a “screening” test and control over the course of a known pathological process, the study of GGTP is literally irreplaceable in terms of clinical significance.

GGTP is especially sensitive to the effect on the liver of prolonged alcohol consumption. In alcohol abusers, serum GGTP levels correlate with the amount of alcohol consumed.The test is especially valuable for monitoring alcoholism treatment. Stopping alcohol intake reduces enzyme activity by about 50% over a period of 10 days.

Determination of GGTP activity is used to establish the fact of damage to liver cells and is usually increased in 90% of cases of liver disease. In most cases, in such patients, an increase in the activity of ALT and GGTP is observed in the blood. An isolated increase in the activity of GGTP is observed in 6-20% of patients with pathology of the hepato-biliary system.

In acute hepatitis, the activity of GGTP rises earlier than the activity of ALT. At the peak of the disease, the activity of GGTP is lower (increased by 2-5 times) than the activity of ALT, and normalizes much more slowly. This allows the use of GGTP as a control of the patient’s recovery.

An increase in the activity of GGTP by more than 3 times is caused by anticonvulsant drugs, fatty degeneration of the liver and heart failure.

The highest activity of GGTP (5-30 times higher than the reference interval) is observed in intra- and extrahepatic cholestasis.Slightly lower values ​​of the enzyme activity are recorded in primary liver tumors and liver metastases. A persistent and long-term recorded increase in GGTP may be the only clinical and laboratory sign of metastatic liver disease.

90,000 Medical analyzes – Alanine aminotransferase (ALT)

ALT and AST are the most important representatives of aminotransferases or transaminases (a group of enzymes that catalyze the conversion of alpha-keto acids into amino groups by transferring amino groups).A significant increase in ALT occurs only in liver diseases, since this is a specific enzyme. However, an increase in AST levels can occur due to damage to the heart or skeletal muscles, as well as damage to the liver parenchyma. Therefore, parallel measurement of AST and ALT is used to differentiate liver damage from cardiac or skeletal muscle damage. The ratio of AST to ALT is used for the differential diagnosis of liver diseases. A ratio <1 indicates mild liver damage, while a ratio> 1 indicates multiple, often chronic liver damage.

Reference values ​​

Age Enzyme activity in U / L
Men Women
Children from birth to 12 months 13 – 45 13- 45
Age from 12 months to 60 years 10 – 40 7 – 35
Adults aged 60 to 90 13 – 40 10 – 28
Adults over 90 6 – 38 5 – 24

Factors increasing the result:

  1. hepatotoxic (toxic to liver cells) and cholestasis (bile stasis) drugs
  2. intramuscular injection (moderate increase)

Many medications can cause an increase in ALT, usually transient, but in some cases this increase may indicate hepatotoxicity.
Among these drugs:

Acebutalol, Aminoglycosides, Azithromycin, Bromocriptine, Captopril, Cephalosporins, Clarithromycin, Clindamycin, Clofibrate, Clotrimazole, Cyclosporin, Cytarabine, Dacarbazine, Didanosin, Enflokirinethyramide, Phyrophylactin Interferon, Interleukin-2, Labetalol, Levamisole, Levodopa, Lincomycin, Mebendazole, Meflokin, Metoprolol, Nifedipine, Otmeprazole, Ondasetron, Penicillins, Pentamidine, Pindolol, Piroxicam, Propoxyphene, Protriptyline S, Quinine, Rhetocymidine Sulfonyl – urea, Thiothixen, Thioguanine, Trimethoprim, Verapamil, Zalcitabine, Zimelidine.

Increased activity

  • necrosis of liver cells of any etiology
  • severe shock
  • Right ventricular failure
  • left ventricular failure
  • major trauma
  • liver cirrhosis
  • obstructive jaundice
  • liver tumors.
  • Major myocardial infarction
  • myositis
  • myocarditis
  • progressive muscular dystrophy
  • preeclampsia
  • Moderate muscle injury
  • fatty liver hepatosis
  • chronic alcoholism
  • philariasis
  • burns
  • pancreatitis
  • gangrene of the extremities

Decrease in activity: deficiency of pyridoxal phosphate, which is a prosthetic group of the enzyme (derivative of vitamin B6).

Alanine aminotransferase, ALT, ALT, Transaminases in Moscow inexpensively

Alanine aminotransferase is produced by cells of the human body to catalyze metabolic processes. The largest amount of the enzyme is formed in the liver and is normally almost completely involved in reactions. With various pathologies, the level of ALT in the blood rises. As a result, the study of alanine aminotransferase is used to diagnose acute and chronic diseases: hepatitis, diseases of the cardiovascular system, gastrointestinal tract, skeletal muscles – and to evaluate the effectiveness of the stages of their therapy.

Analysis of the transaminase index and identification of the size of the deviation from normal values ​​is carried out in conjunction with ultrasound data, studies of markers of viral hepatitis, other indicators of biochemistry: total bilirubin, G-GTP, AST, ALP. Indications for testing are symptoms of lesion or situations of increased risk of liver damage, chronic alcoholism, previous contacts with patients with viral hepatitis, hereditary diseases, diabetes.

Determination of alanine aminotransferase

Transferases, which include alanine aminotransferase, or glutamate-pyruvate-transaminase, are involved in protein-carbohydrate metabolism – in cyclic reactions of conversion of amino acids into keto acids, transamination.The enzyme ALT is highly active in the tissues of the kidneys and liver, comparatively less in the tissues of the spleen, myocardium, lungs, skeletal muscles, and pancreas. An increase in the amount of the enzyme in the bloodstream occurs when the cells of these organs are damaged: nephorones, hepatocytes, cardiomyocytes, myocytes.

Indications for analysis ALAT

Study of the ALT indicator is prescribed in the presence of symptoms of liver dysfunction: loss of appetite, nausea, vomiting, fatigue and weakness, pain in the right hypochondrium, yellowness of the whites of the eyes or skin, staining of feces in a light color, darkening of urine.

Analysis of blood biochemistry for ALT is carried out to confirm the diagnosis of the following liver diseases:

  • hepatitis of a viral, autoimmune, toxic nature;
  • cirrhosis;
  • steatosis;
  • malignant neoplasms.

Overweight patients taking drugs that are toxic to the liver, alcohol abuse, diabetes or a history of hereditary hepatic pathologies are also prescribed blood biochemistry with ALT determination.

In addition, testing of alanine aminotransferase parameters is performed in the following situations:

  • diagnostics of pathologies of skeletal muscles, pancreas, kidneys, gallbladder, spleen;
  • survey of contacts for viral hepatitis;
  • examination of blood donors;
  • monitoring of medication intake;
  • inflammation, soft tissue damage: trauma, burns;
  • in the presence of shock.

ALT study is prescribed as part of a comprehensive examination for the detection of viral infections, malignant tumors, diseases: myocardial infarction, pericarditis, myocarditis, hypothyroidism, hemolytic anemia, myopathy

Analysis for the level of alanine aminotransferase is carried out in patients with chronic diseases before starting drug therapy. Further in the course of treatment, testing is carried out in order to control the dynamics, the tolerance of drugs, the state of the liver are checked.

Identification of pathologies and their features by the value of transaminase

To a large extent, the activity of the enzyme increases with medicinal and viral hepatitis. There is a proportional relationship between its amount in the bloodstream and the severity of the disease. For the diagnosis of pathologies, it is important that the ALT level exceeds the norm even before the onset of the jaundice stage. Alanine aminotransferase also increases already in the early stages of infectious and toxic hepatitis and, with favorable development, gradually decreases over several weeks.In case of liver damage due to alcohol exposure, the excess from the reference intervals is not so significant.

Natural causes also affect the amount of transaminase in the blood. The enzyme level increases due to factors affecting the condition of the muscles, such as multiple intramuscular injections, intense exercise. Enzyme production is affected by liver-depressing drugs, dietary supplements, excessive consumption of alcoholic beverages, and food intake containing many food additives.

Causes of deviations in the level of alanine aminotransferase from the norm

A significant increase in the level of alanine aminotransferase can be observed in case of poisoning with potent drugs, lead, carbon tetrachloride, while taking narcotic analgesics, as well as in diseases:

  • infectious mononucleosis;
  • hepatitis, cirrhosis, cholestasis, liver cancer;
  • fatty hepatosis;
  • acute myocardial infarction;
  • pericarditis;
  • myocarditis;
  • renal, heart failure;
  • destructive pancreatitis;
  • myodystrophy;
  • myositis;
  • acute cholecystitis;
  • gallstone disease;
  • 90,011 extensive soft tissue lesions.

An increase in the number of ALT in most cases indicates damage to hepatocytes and disruption of their normal functioning. Metabolic pathologies cause liver infections, autoimmune processes, neoplasms, diseases that provoke ischemia, circulatory disorders, the use of substances toxic to the liver.

Hepatotoxic drugs: alcohol, food additives, psychotropics, anabolic steroids, COCs, immunosuppressants, antibiotics, anesthetics.

Reasons for a decrease in the level of alanine aminotransferase:

  • liver necrosis;
  • decompensated cirrhosis;
  • vitamin B₆ deficiency in the body.

Extensive liver damage leads to a decrease in the number of hepatocytes and, as a consequence, to a decrease in the level of ALT in the tissues of biological fluids. Vitamin B₆, along with ALAT, is involved in transamination, therefore, for the normal activity of the enzyme, its intake with food should be sufficient.

Treatment of pathologies causing abnormal ALT levels

Deciphering the result of the analysis of biochemistry for ALT is carried out in conjunction with the results of complex biochemistry, data on aspartate aminotransferase.The following specialists are involved in the therapy of diseases that cause an increase or decrease in the level of transaminase in the blood: hepatologists, cardiologists, gastroenterologists, endocrinologists, nephrologists, infectious disease specialists, therapists.

Treatment is aimed at eliminating the causes of pathological processes. Medicines are combined with dietary food. For liver diseases, drugs are prescribed that improve digestion, choleretic, hepatoprotectors. Most of the prescriptions are plant foods rich in vitamins, especially vitamins B and D.The amount of salt and animal fats is limited. It is important to exclude nicotine, alcohol, hepatotoxic substances, the intake of which is not agreed with the doctor.

Symptoms of heart muscle damage associated with an increase in alanine aminotransferase require consultation with a cardiologist. In this case, the doctor additionally prescribes echocardiography, electrocardiography (ECG), blood tests for troponin I, MV-CPK. Clarification of the diagnosis of damage to the musculature of the skeleton is carried out by a rheumatologist. In addition to ALT, the level of the enzyme creatine kinase is investigated.

Preparation for analysis

There are no contraindications to the study of ALT, but taking a biomaterial is not recommended without performing a set of preparatory measures. Blood is drawn from a vein in the morning on an empty stomach. The last meal with limited fat and no alcohol should be 8-14 hours before manipulation. During the period of abstinence, it is allowed to drink non-carbonated water. In the hour interval preceding the procedure, smoking, emotional and physical stress are excluded.Data on the intake of medications relevant for testing are reported to the doctor. Biochemistry is not performed after massage, physiotherapy, X-ray and ultrasound studies. It is allowed to take the analysis in the daytime if the previous meal was lightweight.

Donate blood biochemistry for alanine aminotransferase

We invite you to take a biochemical blood test for ALT in one of our medical centers within walking distance from the subway ring stations. Our clinics are equipped with high-tech equipment and professional staff.We offer accurate blood sampling, accurate testing, low prices. Contact us!


Blood is taken from a vein. General recommendations must be followed:

  • blood is donated in the morning on an empty stomach or not earlier than 2–4 hours after a meal;
  • it is allowed to use water without gas;
  • on the eve of the analysis, alcohol should be abandoned, physical and emotional overstrain should be excluded;
  • quit smoking 30 minutes before the study;
  • You should not donate blood during the period of taking medications, unless the doctor has prescribed otherwise.

AsAT (AST, aspartate aminotransferase, AST, SGOT, Aspartate aminotransferase)

What is AST (AST, aspartate aminotransferase, AST, SGOT, Aspartate aminotransferase)?

Aspartate aminotransferase (AST, Aspartate aminotransferase) is an enzyme found in the highest concentration in the liver and heart, in a smaller amount in the cells of the kidneys, skeletal muscles, etc.e. When these organs are damaged, the level of AST in the blood rises, while normally it is quite low.

The degree of AST level increase depends on the extent of organ damage. Very high values ​​may indicate a necrotic lesion.

The level of AST activity is usually determined in conjunction with another enzyme – ALT (alanine aminotransferase), since both are present in various tissues of the body. In most diseases associated with an increase in AST concentration, ALT values ​​also increase.The AST / ALT ratio (de Ritis ratio) is used to verify which organ is damaged: liver or heart / muscle tissue. In most liver diseases, this ratio is low, but there are a few exceptions: alcoholic liver damage; cirrhosis of the liver caused by chronic hepatitis C, etc.

Why is the level of AST in the blood determined?

Determination of the AST level is included in the screening of liver diseases. In addition, the study includes the determination of the level of alkaline phosphatase (ALP), bilirubin and its fractions, total protein, ALT, GGT (gamma glutamyl transpeptidase) and some other markers.

With the help of the AST level, the course of treatment of liver diseases is monitored.

AST values ​​must be taken into account to confirm or refute cardiac pathology.

In what diseases does the AST level in the blood increase?

The level of aspartate aminotransferase is significantly increased in diseases of the heart muscle (myocardial infarction), liver (hepatitis, liver cancer), with acute or chronic inflammation of the bile ducts, as well as pathologies of skeletal muscles, including trauma.

In addition, an increase in AST values ​​is observed as a result of taking hepatotoxic drugs, extensive burns, heat stroke, etc.

Why can the analysis result be incorrect?

There are a number of factors that can negatively affect the correctness of the research result. These include: intense physical activity 1-3 days before the test, recent X-ray examinations, any physiotherapy procedures, ultrasound, heart surgery.

AST values ​​can be distorted due to the intake of alcohol and certain medications (antineoplastic, choleretic, antibacterial, sedative, oral contraceptives, etc.). (The list of medications to take should be discussed with the doctor who ordered the test).

It is preferable to take blood in the morning on an empty stomach, after 8-14 hours of the night fasting period (you can drink water), it is permissible in the afternoon after 4 hours after a light meal.On the eve of the study, it is necessary to exclude increased psychoemotional and physical activity (sports training), alcohol intake.

Interpretation of test results contains information for the treating physician and does not constitute a diagnosis. The information in this section cannot be used for self-diagnosis and self-medication.An accurate diagnosis is made by a doctor, using both the results of this examination and the necessary information from other sources: anamnesis, results of other examinations, etc.

Units of measurement: Unit / l.

Reference values:

Age AsAT, U / l
<5 days <97
5 days – 6 months <77
6 – 12 months <82
1 – 3 years <48
3 years – 6 years <36
6 – 12 years old <47
Women 12 – 17 years old <25
> 17 years old <31
Men 12 – 17 years old <29
> 17 years old <37

Increasing values:

  1. Fulminant form of acute hepatitis, especially viral (sharp increase).
  2. Necrosis or damage to liver cells of any etiology, including cholestasis and obstructive jaundice, chronic hepatitis, drug-induced liver damage.
  3. Alcoholic hepatitis (AST usually> ALT).
  4. Viral and chronic hepatitis (ALT> AST in most situations).
  5. Neoplasms in the liver.
  6. Infectious mononucleosis.
  7. Necrosis or injury to cardiac or skeletal muscles.
  8. Acute myocardial infarction (AST> ALT).
  9. Heavy muscular load.
  10. Heart failure.
  11. Severe burns.
  12. Heatstroke.
  13. Hypothyroidism (in 40-70% of cases).
  14. Intestinal obstruction (may indicate small intestinal infarction).
  15. Lactic acidosis.
  16. Legionnaires’ disease.
  17. Malignant hyperthermia.
  18. Polymyalgia rheumatica.
  19. Typhoid fever.
  20. Thalassemia is large.
  21. Toxic shock syndrome.
  22. Increased or normal concentration in cirrhosis, neurological diseases, ischemic or hemorrhagic stroke, acute pancreatitis, kidney infarction, hemolytic anemia, malnutrition, obesity.
  23. Rare metabolic diseases (lysosomal acid lipase deficiency, Wilson-Konovalov disease, Gaucher disease, etc.).
  24. The use of hepatotoxic drugs or drugs that cause cholestasis, many other drugs can also cause an increase in AST, which is usually temporary, but may indicate hepatotoxicity (including antibiotics, statins, some antiviral drugs, etc.).

Indirect markers: C-D-T.RU

Laboratory markers of alcohol consumption are divided into groups of direct and indirect biomarkers. Biomarkers differ in the mechanisms of their pathological increase, which largely determine their analytical specificity; the dose of alcohol and the duration of its use required to increase the concentration of the biomarker; half-life (or metabolic period) in the human body, and this indicator is extremely important in assessing the diagnostic significance of the marker in relation to the differentiation of chronic abuse and the possibility of early detection of relapse.

The group of indirect markers includes a wide range of indicators, the analytical characteristics and diagnostic significance of which can vary within wide limits.

1. Average erythrocyte volume ( MCV )

Mean Red Blood Cell Volume (MCV) is an index of red blood cell size and is calculated as the ratio of hematocrit to red blood cell count. The mechanism by which alcohol causes an increase in MCV is the direct toxic effect of alcohol on red blood cells.Folic acid and vitamin B12 deficiencies secondary to alcohol consumption and liver damage can also cause an increase in MCV. Increases in MCV are observed in chronic abuse and correlate with both the amount taken and the frequency of use. However, the change in MCV in response to a change in the level of alcohol consumption is very slow: an increase in MCV can occur only after 1 month of consuming more than 60 g of alcohol per day; it may take several months of abstinence to normalize MCV.MCV is not an informative marker for monitoring acute alcohol consumption, relapses or binges due to the slow response of the indicator to changes in the amount of alcohol entering the body, which is due to the long half-life of red blood cells (the life cycle of an erythrocyte is 100 -120 days). MCV may increase nonspecifically in individuals with hypothyroidism, reticulocytosis, and smokers. Low specificity of the marker is observed when testing elderly patients.MCV can be lowered in people with iron deficiency (alimentary anemia, bleeding of various origins), with thalassemias and a number of chronic diseases (for example, with chronic gastrointestinal diseases). Thus, the main disadvantage of the MCV marker is its low sensitivity (40-50%) and insufficient specificity in both inpatients and outpatients.

2. Aspartate aminotransferase (AST) and alanine aminotransferase (ALT)

An increase in the level of aspartate aminotransferase is often the first detectable indicator of the response of hepatocytes to the effects of drugs and toxic agents.The level of AST and ALT reflects generalized damage to liver cells or an increase in the permeability of cell membranes of both alcoholic and non-alcoholic genesis. Both enzymes enter the bloodstream when cell membranes are damaged and are present in many tissues, while most tissues contain less AST than ALT; the only exception is liver tissue, where both enzymes are present in approximately equal concentrations. AST and ALT levels (half-lives of 17 and 47 hours, respectively) increase in the case of alcohol abuse, but due to extremely low sensitivity and specificity, these markers cannot be considered as independent indicators of chronic abuse.

3. Gammaglutamyltransferase (GGT)

Gammaglutamyltransferrase (GGT) is a membrane glycoprotein (enzyme) that catalyzes the transfer of the gammaglutamyl residue of glutathione to various protein acceptors. The elevation of serum GGT in response to varying amounts of alcohol and for different durations of abuse can vary significantly from patient to patient. First of all, GGT is an indicator of chronic use of high doses of alcohol, but remains within the normal range in drunken alcoholics and in those who drink but do not abuse, if they do not have concomitant liver diseases.The half-life of GGT (the time it takes for the enzyme to halve its initial activity) is 14 to 26 days, and the serum concentration of the enzyme usually returns to normal 4-5 weeks after stopping alcohol.

The sensitivity of GGT in persons with a high alcohol load (from 40 to 540 g of alcohol per day), according to a number of studies conducted in Finland, is 58%. Individuals who consume critically high amounts of ethanol, but are not classified as addicts, have significantly lower GGT sensitivity (20-50%), especially when diagnosed in primary health care facilities.A physiological increase in the level of GGT is observed in people over 65 years old, regardless of the amount of alcohol they drink, and, on the contrary, in people under 30 years old, the physiological level of GGT may be lowered.

In a large-scale study of the Finnish population (3974 men and 2988 women), it was shown that GGT has a low sensitivity and low diagnostic value in differentiating persons with a high alcohol load (over 280 g per week) from those with an average (105-280 g in week) and low (105 g per week) load.

GGT may increase nonspecifically in diseases of the pancreas, type II diabetes, obesity, hypertension, myocardial infarction, chronic obstructive pulmonary disease and renal failure. A more pronounced GGT response is seen in chronically abusive men from South Asia, Brazil, Mexico, and Africa.

Thus, the main disadvantage of this biomarker is its low specificity. A number of drugs and pathological conditions can increase GGT, leading to false positive diagnostic results.Despite the drawbacks, the measurement of the GGT level when used in combination with other, more specific markers, such as, for example, carbohydrate-deficient transferrin, can give good, diagnostically significant results.

In general, the traditional indirect markers of alcohol consumption described above can be characterized as inexpensive, simple to implement, but insufficiently reliable indicators that have a number of significant limitations:

a) these indicators do not reflect alcohol abuse itself, but liver dysfunctions associated with abuse.Thus, these tests have a rather low diagnostic specificity, since they give false-positive results in a number of liver diseases not associated with alcoholism, as well as when taking certain medications;

b) in addition, some of these tests are not sensitive enough to detect the fact of alcohol abuse before the onset of organic liver damage;

c) the specificity and sensitivity of these markers vary widely depending on gender, age, concomitant pathology, not meeting the criteria of the “ideal marker”.

4. Carbohydrate-deficient transferrin (CDT)

In recent years, a new marker, carbohydrate-deficient transferrin (CDT), has been increasingly used in world practice. According to the literature, including published results from large multicenter, clinical and validation trials, CDT has the best analytical performance among the existing laboratory markers of chronic abuse. A specific increase in CDT is observed in persons consuming at least 50-80 g of alcohol for at least 7-10 days, which allows establishing the fact of chronic abuse in the laboratory.

At the same time, in the majority of patients with liver diseases, the CDT level remains within the normal range, which compares favorably with the indicators of GGT, ALT and AST. Certain chronic liver diseases (primary biliary cirrhosis, highly active chronic hepatitis, severe decompensated cirrhosis) can cause false positive results. Nevertheless, according to the data of various studies, this marker demonstrates the highest indicators of specificity and sensitivity (Table 1).

Table 1. Comparative characteristics of the marker CDT *

Characteristics of the indicator






About 70%







14-17 days

2-3 weeks

3 months

Time required to normalize the indicator after cessation of use

4 weeks

2 months

3-4 months

Threshold for alcohol consumption causing a positive result

50-80 g per day

80-200 g per day

<80 g / day

A period of regular alcohol consumption that produces a positive result

1 week

several weeks

several months

* The variability of the indicators is explained by the difference in the analytical characteristics of the methods for assessing markers, the characteristics and size of the sample of research participants, etc.

World Health Organization in the study “Comparative Quantification of Health Risks” (“Comparative study of risk factors”) from 2004 identifies 4 categories of people, depending on the amount of alcohol consumed.


Daily consumption of absolute alcohol, g

Risk level



Not using

0 during the last year


Average alcohol consumption, category I

0 – 39.99



Average alcohol consumption, category II




Average alcohol consumption, category III

over 60

over 40


The daily consumption of alcohol by men and women in amounts exceeding 100 g and 60 g, respectively, is a very high risk of developing alcohol-related diseases.
The CDT marker allows you to identify individuals with an average (or higher) risk of such diseases.

In 2005, the CDT marker was approved by the Food and Drug Administration (FDA) as an indicator of chronic abuse, and is now widely used in Western Europe and the United States.