Blood test for liver tests: preparation, how to take, what shows
Last reviewed: 23.04.2024
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To assess liver function, special studies are performed - liver tests. Let's consider features of the given analysis: indications, a method of carrying out, decoding of results.
The liver is the largest gland of the human body. It occupies the upper right part of the abdominal cavity, located under the diaphragm. In it, all the vital biochemical reactions occur, the violation of which causes a number of negative consequences for the whole organism. The parenchymal organ has increased regenerative and regenerative abilities, but the complex structure and high loads make the liver vulnerable.
The main functions of the liver:
- Detoxification - neutralizes toxic compounds entering the blood from the environment (toxins, food and drinks, medicines) and removes them from the body.
- Regulation of carbohydrate, lipid, protein, bilirubin and vitamin metabolism.
- Synthesis of hormones: sexual, thyroid, adrenal.
- Synthesis of bile and enzymes involved in the process of digestion and fission of fats.
- Hemopoiesis and the synthesis of plasma clotting factors of the blood system.
- Deposition (storage) and distribution of glucose and glycogen (energy substrates).
- Synthesis of immunoglobulins, antibodies and other proteins of the immune system.
- The deposition of blood and its distribution with the needs of the body.
With changes in the work of the body, there is a violation of its functions and the general condition of the organism worsens. To determine the cause of painful symptoms, patients are prescribed hepatic tests. This study is a complex of analyzes that allow to identify various pathologies in the early stages and conduct an objective assessment of the basic functions of the liver.
What is the name of the test for hepatic tests?
The liver is a kind of laboratory of the body, in which every minute there is a lot of chemical reactions. Her work depends on the substances entering the body. Conducting a special complex of laboratory studies allows obtaining detailed information about the state of the organ and digestive tract.
The functional characteristics of the liver are determined in the course of various procedures. The analysis for hepatic assays is called screening and is estimated by such indicators:
- Bilirubin.
- ALT (alanine aminotransferase).
- ACT (aspartate aminotransferase).
- GTT (gamma-glutamyltransferase).
- Alkaline phosphatase.
- The total protein (especially studied albumin).
In the course of the study, all the above-mentioned indicators or certain of them can be determined. The cost of laboratory diagnostics depends on the number of analyzes. For a comprehensive assessment of the liver, three basic analyzes are mandatory:
- An expanded biochemical blood test.
- Coagulogram.
- General urine analysis.
The first analysis reveals pathological processes, determines their causes and gives information on the excretion of bilirubin from the body, the creation of protein, albumins and other substances. Coagulogram defines abnormalities in the coagulation system to reduce the risk of increased bleeding. A general analysis of urine allows you to assess the general condition of the body, liver and kidneys.
Indications for conduction
The danger of liver disease is that they have a latent flow, rapidly progressing and can cause death. That is why it is necessary to consult a doctor and undergo laboratory diagnosis if there is such a symptomatology:
- Sharp weight loss for no apparent reason.
- Frequent attacks of nausea and vomiting.
- Increased weakness.
- Fast fatiguability.
- Puffiness of the abdomen, lower limbs and skin around the eyes.
- Heaviness and pain in the right hypochondrium.
- Diarrhea or discolored feces.
- Darkening of the urine.
- Jaundice shade of sclera and skin.
- Flatulence for a long period of time.
In addition to the above symptoms, indications for the analysis of liver tests are suspected of such pathologies:
- Chronic liver diseases.
- Alcohol abuse for an extended period of time.
- Transfusion of blood and its components.
- Cirrhosis of the liver.
- Diabetes.
- Disorders from the endocrine system.
- Hepatitis: viral, drug, autoimmune, toxic, allergic.
- Changes in the liver on ultrasound.
- Low level of ALT, AST.
- High level of iron, gammaglobulin.
- Low level of thyroid stimulating hormone, ceruloplasmin.
- Hormonal failures.
- Observation of side effects of ongoing drug therapy, especially antibiotic treatment.
- Evaluation of the effectiveness of the treatment.
- Preparing for surgery for any reason.
- Planning of pregnancy.
If the results of the analysis have elevated levels of ALT and AST, then this indicates damage to the body cells. The level of albumin shows the efficiency of protein synthesis. Bilirubin - how much the liver performs its detoxification function. As an additional examination, a thymol test can be administered to evaluate the protein-synthetic function.
It should be borne in mind that changes in hepatic samples do not always indicate liver damage. For a comprehensive evaluation of the results of the analyzes, anamnesis is collected, the presence of painful symptoms is taken into account, visual inspection of the patient and a number of diagnostic tests are also required.
Preparation
To ensure that the analysis for hepatic assays is as reliable as possible, it is necessary to properly prepare for it.
24 hours before the study you need:
- Exclude increased physical activity.
- Eliminate fatty foods and alcohol from the diet.
- Minimize stressful conditions.
- Refuse to smoke.
- Do not drink strong tea or coffee.
- Take only prescribed medicines.
- With existing liver diseases, carry out tjubazh (purification of the gallbladder).
Particularly affected by the falsity of the results of the tests are antibiotics, antidepressants, hormonal oral contraceptives, chemotherapy drugs, barbiturate drugs, as well as Aspirin, Paracetamol, Phenytoin.
Who to contact?
Techniques for conducting
Analysis for liver tests is indicated for suspected liver disease, as well as for the presence of pathological symptoms: yellowing of the skin, abdominal pain and right hypochondrium, nausea, vomiting. The study is aimed at identifying:
- Inflammatory processes.
- Stagnation of bile.
- Lesions of hepatic ducts.
- Viral diseases and a number of other problems.
The technique of performing hepatic tests involves tracking any changes in the liver. The main technique consists of venous blood sampling. At the same time, special attention is paid to preparation for analysis. The patient should adhere to a certain sparing regimen, because the body reacts to any changes in the body.
The analysis is carried out on an empty stomach. For two or three days should be abandoned fatty and fried foods, alcoholic beverages. Particular attention should be paid to medicines, because taking certain medications leads to false results of the samples.
How to take liver tests?
The analysis is taken in a treatment room in a polyclinic or in a specialized laboratory. As a rule, the study is conducted in the medical field. Before passing the liver tests, the patient should limit physical activity, refuse to take alcohol and harmful food.
Also, you should cancel the medication for 7-10 days before the test. If, for medical reasons, this can not be done, then it is necessary to inform the doctor about what medicines and in what dosage they were taken.
The study is conducted on an empty stomach, you can drink only a couple of sips of water. Since the last meal, at least 8-12 hours must pass. Also, if necessary, for 5-7 days before the analysis is carried out tjubazh.
How is the hepatic test taken?
Blood sampling for liver tests is performed from the ulnar vein in a standard way. This study is part of the biochemical blood test. To reduce the risk of obtaining false results, there are certain requirements for the blood sample:
- For analysis, 5 ml of venous blood are collected.
- The harness before blood sampling is applied for 1-2 minutes. This is necessary to avoid false-high values of albumins.
- The biological fluid is stored and transported in a dark container, as bilirubin is destroyed under the action of light.
Immediately after the analysis, the patient is offered to sit for a while to prevent dizziness and fainting. Complications from taking the sample are rare, but can manifest themselves with such symptoms: prolonged venous bleeding, hemorrhage under the skin at the site of the vein puncture, infection of the vein with the development of phlebitis. The results of the analysis are ready within 1-5 days. According to them, the doctor makes a further diagnosis plan.
Interpretation of test results for hepatic assays
Evaluation of screening for the functional state of the liver should be handled only by a qualified doctor.
Main indicators of the study:
Indicators |
Women |
Men's |
Bilirubin, μmol / l: |
||
General information |
8.5 - 20.5 |
8.5 - 20.5 |
Straight |
Up to 15,4 |
Up to 15,4 |
Indirect |
Up to 4,6 |
Up to 4,6 |
Total protein, g / l |
60 - 80 |
60 - 80 |
Albumin,% |
40-60 |
40-60 |
ADT, IT / L |
Up to 31 |
Up to 47 |
ALT, ED / L |
Up to 31 |
Up to 37 |
GGTP, U / L |
Up to 32 |
Up to 49 |
Correct interpretation of the results of the analysis makes it possible to assess the nature of disturbances in the work of the organ, its detoxification abilities and a number of other functions. Also, liver tests make it possible to analyze metabolic processes and the state of the body after prolonged drug therapy.
With significant changes in the indicators above or below the norm, a second study is conducted. This is necessary to eliminate errors during the laboratory diagnosis or violation of the rules of preparation for the samples.
What does the blood test show for liver tests?
Hepatic tests are a comprehensive laboratory screening. With its help it is possible to identify diseases of the liver or bile ducts at their early stages. The study is aimed at determining the concentration of such substances:
- Aspartate aminotransferase.
- Alanine aminotransferase.
- Alkaline phosphatase.
- Gamma-glutamintranspeptidase.
- Bilirubin: direct, indirect, general.
- Albumin (a protein of blood serum).
- Timole sample.
The results of biochemical diagnostics make it possible to evaluate functional features of the organ, detoxification of harmful substances, peculiarities of bile production and analyze metabolic processes in the body.
Normal performance
When deciphering the results of biochemical screening of the liver, the physician is guided by the normal parameters of the analysis. Deviations from normal both upward and downward may indicate various pathological processes in the body.
Reference values of liver samples for adults by main indicators:
- AST - 0,1-0,45 mmol / hour / l.
- ALT - 0.1-0.68 mmol / h).
- GGTP - 0.6-3.96 mmol / h / l.
- ScF - 1-3 mmol / h / l).
- The total bilirubin is 8.6-20.5 μmol / l.
- Direct bilirubin - 2.57 μmol / l.
- Indirect bilirubin - 8.6 μmol / l.
- The total protein is 65-85 g / l.
- Albumin - 40-50 g / l.
- Globulin - 20-30 g / l.
- Fibrinogen - 2-4 g / l.
In the extended biochemical analysis, the values of additional parameters are taken into account to assess the functional abilities of the liver: glucose, urea, cholinesterase, lipase, cholesterol, prothrombin. The presence of abnormalities serves as an excuse for further diagnosis of the condition of the organ.
The norm of hepatic tests for women
The indicators of laboratory tests in women can vary depending on the age and hormonal characteristics of the body. The significance of certain enzymes increases not only with liver pathologies, but also during pregnancy, lactation.
The norm of the main markers of liver samples for women:
Index |
Value |
It is |
10-30 MEU / l |
GOLD |
7-40 IU / l |
GHGP |
8.8-22.0 MEU / l In pregnant women up to 36 IU / l |
APF |
Up to 31 years 39-92 IU / l Older than 31 years 39-117 IU / l II trimester up to 190 IU / l III term to 240 IU / l |
Total bilirubin |
3.4-17.1 μmol / L In pregnant women 3.4-21.6 μmol / l |
Total protein |
65-85 g / l |
Albumen |
35-50 g / l |
The obtained results of the study are compared with the established norms. The doctor analyzes the analysis, taking into account the presence of risk factors (alcohol abuse, medication, pregnancy and others). Also, the error in the results depends on the equipment used in the laboratory.
Norm of hepatic tests for men
To assess the liver, a laboratory screening of the main enzymes of the organ is carried out. Consider the normal values of hepatic test markers for men:
- ALT - 10-50 U / l. Elevated values may indicate viral hepatitis, alcohol intoxication, the presence of parasites in the liver, cirrhosis.
- AST - 15-21 U / l. Deviation in either direction indicates damage to the hepatocytes. If the level of the enzyme is 20-50 times higher, then this is a sign of viral hepatitis, an organ tissue necrosis.
- GGTP - 2-55 units / liter. Elevated indicators are characteristic for alcohol poisoning, hepatitis, cholestasis.
- Bilirubin - the norm of the total 6-20.5 μmol / l, direct 3.4 μmol / l, indirect 3.5-18.5 μmol / l. An increase in the level of the enzyme can be associated with helminthiasis, cirrhosis, viral hepatitis, bile duct infection.
- Alkaline phosphatase - the rate of this enzyme depends on the age of the patient. In men under the age of 30, APF 31-92 IU / l, after 30 years - 38-117 IU / liter. Elevated values are observed in violation of metabolic processes in the body, cirrhosis, cholestasis, alcohol intoxication. If the APR is lowered, then it speaks of diseases from the thyroid gland.
The obtained results are compared with the established norms for detecting any deviations.
Apparatus for analysis
The analysis for hepatic tests is carried out on the basis of venous blood. The biological fluid is examined by automated methods. The determination of the basic enzymes is carried out with the help of various apparatuses. Markers of the liver are studied by flow cytofluorometry using laser semiconductors and hydrodynamic focusing. It is also possible to use colorimetric and kinetic analyzers.
In modern medical laboratories for the analysis of liver tests, the Cobas 6000 (with 501 module) is used. Modular analytical system provides a wide range of biochemical and immunochemical tests.
The device is characterized by a flexible combination of different modules, which makes it possible to create a consolidated serum working area, as well as specialized immunochemical and biochemical systems. The device identifies all liver enzymes, substrates and specific proteins.
Elevated liver tests
Very often in the results of tests for hepatic tests, the excess of the norms of various enzymes is indicated. As a rule, the changes relate to ALT and AST, so consider the main reasons for their increase:
- Improper preparation for analysis: eating less than 10 hours before the study, abuse of alcohol, fatty and fried foods, increased physical activity. False results arise when using certain groups of drugs.
- Painful symptoms indicating liver damage: icterus of skin and mucous membranes, discomfort in the right hypochondrium, nausea and vomiting, skin itching, increased fatigue.
- Previously transferred viral hepatitis, pancreatitis, peptic ulcer, cholecystitis, gastrointestinal disease, skeletal muscle damage or cardiovascular system.
Elevated enzymes may indicate not only the pathology of the liver, but also other organs in which there is a transaminase. Also, the change in indicators can be associated with early pregnancy.
Hepatic assays reduced
The fall in the parameters of laboratory analysis of liver enzymes is much less common than the elevated values of liver tests.
Let's consider the main reasons for the decrease in the results of screening:
- Bilirubin - chronic renal failure, tuberculous intoxication, acute leukemia, aplastic anemia, alimentary depletion, low red blood cell count.
- AST and ALT - vitamin B6 deficiency, total necrosis, liver rupture, cirrhosis. Indicators below the norm arise in cancer processes in the body, infections of the genitourinary system, pancreas, as well as in preterm infants.
- Alkaline phosphatase - anemia of blood, deficiency of thyroid hormones, intoxication with metals. Deficiency of vitamin B12, ascorbic acid, zinc, magnesium. Blood transfusion in a significant amount, hypophosphatosis, placental insufficiency during pregnancy.
- Total protein and albumin - cirrhosis, atrophy, hepatitis, liver carcinoma. Long-term fasting and low-protein diets, pathology of the gastrointestinal tract. Injuries to tissues and burn injuries. Nephrotic syndrome, kidney disease. Condition after heavy bleeding, blood infection, infectious diseases, hyperhydration. Heart failure is stagnant, hereditary pathologies, newborns.
- Gamma-glutamyltransferase - an unbalanced diet, a deficiency of vitamins and minerals in the body, increased physical activity, vegetarianism. A low level of GGTP is observed in patients who are treated for alcoholism when using hormonal contraceptives or ascorbic acid.
- Prothrombin time - deficiency of vitamins and minerals, cirrhosis, hepatitis, myeloleukemia, hormonal drugs and anticoagulants.
Indicators below the norm may be caused by non-compliance with the rules of preparation for diagnosis or violations during the analysis.
Hepatitis C Hepatitis
Anthroponous viral disease of the liver has a characteristic symptom complex, which allows you to suspect a pathological condition, begin its diagnosis and treatment. Hepatitis C tests are performed to detect hepatitis C. Particular attention is paid to the indicators of ALT and AST, which most reliably indicate the degree of organ damage and the features of disease progression.
Viral hepatitis C has a latent flow, so it develops over an extended period of time. Violations of enzyme activity are not immediately apparent. With the destruction of hepatocytes, the results of hepatic tests change.
Laboratory diagnosis of hepatitis C is carried out according to the de Ritis coefficient (ALT and AST ratio):
- If the index is increased by more than 1.3 times, this indicates liver damage.
- If the coefficient is below the norm, then there are suspicions of diseases of the cardiovascular system.
- If the disease takes a chronic course, the indicators are stably overestimated.
Hepatitis C of icteric form is characterized by a simultaneous increase in ALT, direct and total bilirubin. In some cases, the disease proceeds without yellowing of the skin and mucous membranes, therefore it is possible to suspect hepatitis only by increasing the production of enzymatic substances in the results of liver tests.
The final diagnosis of hepatitis C is made on the basis of screenings, instrumental studies, the presence of symptoms characteristic of the disease. After recovery all the enzymes come back to normal.
Hepatic tests for cirrhosis
The pronounced structural changes in the liver tissues that cause hepatic insufficiency, increased pressure in the inflows and portal vein of the organ are cirrhosis. The disease is characterized by chronic course and rapid progression.
The main causes of cirrhosis:
- Alcohol abuse.
- Viral hepatitis.
- Severe intoxication of the body.
- Autoimmune processes.
- Stones in the gallbladder.
- Narrowing or blockage of ducts.
- Helminthiasis for a long period of time.
- Chronic heart failure.
The disease manifests secondary symptoms, which do not always cause anxiety. But as the progression begins to turn yellow skin and sclera of the eyes, there are pains in the right side, attacks of nausea and vomiting, widening of the vascular network.
Hepatic tests are one of the main methods of diagnosing cirrhosis. Let's consider the basic parameters of screening and their value at structural changes of a liver:
- ALT - the level of the enzyme is increased by 10 or more times, reaching 500-3000 IU / l.
- AST - elevated values indicate the process of destruction of hepatocytes.
- GGTP - increases several times. A consistently high level indicates an extremely serious condition of the organ and an active destruction of its cells.
- AFP - elevated values indicate a cytolysis of hepatocytes and a difficult outflow of bile.
- Bilirubin - an increase in the norm of two fractions of more than 20.5 μmol / l, incomplete binding of enzyme molecules.
- Albumin - a decrease in the norm indicates a serious damage to the hepatocytes.
When suspected of having cirrhosis, the patient is prescribed a set of laboratory and instrumental diagnostic procedures that can confirm or disprove the diagnosis. Cure even in its early stages is impossible. Patients are given lifelong maintenance therapy to eliminate painful symptoms.
How much analysis is done for liver tests?
A comprehensive blood test to determine the functional state of biliary tract biliary traction is performed by venous blood sampling. The duration of the study is from 1 to 5 days. If the diagnosis is carried out in a modern medical laboratory using modular analytical systems of the latest generation, the results are ready for the next day.
What to do with bad liver tests?
Decipherment and analysis of the analysis for liver tests should be done only by a doctor. The doctor compares the results with the norm, the general condition of the patient and the presence of painful symptoms.
With significant deviations in the analysis without a pronounced symptom complex, the patient is assigned a repeat study. False results may be due to a violation of the rules for preparing for analysis or laboratory errors.
If elevated enzymes are accompanied by signs of liver damage, additional studies are conducted to better assess the condition of the organ. After complex diagnosis, therapeutic and corrective methods are selected.
Treatment with liver tests
Elevated hepatic enzymes very often act as a signal of the body for large loads on the liver. Similar results of the analysis can be caused by the accumulation of toxins in the body, certain diseases of the liver or other internal organs. Markers are higher than normal when taken during the diagnosis of certain drugs.
If bad tests are all associated with inflammation or liver damage, additional diagnosis is performed and treatment is prescribed. Therapy is aimed not only at the normalization of indicators, but also at eliminating the cause of the disease state.
Most often, treatment with liver tests consists of a sparing diet and the use of hepatoprotectors. This group of drugs restores damaged liver cells, preventing their further destruction. To accelerate recovery, the patient must give up alcohol and smoking, eating fatty foods, coffee and carbonated drinks. Particular attention is paid to the prevention of chronic diseases of the body, which negatively affect the functioning of the liver.