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Liver test normal levels: High, Low & Normal Results, Symptoms & Causes

Liver Function Tests-Ranges-High & Low

Liver Function Tests (LFT)

Liver function tests (LFT) are blood tests, which are commonly performed to assess liver functions or liver injury. LFT is also known by other names such as, liver panel, liver function panel, liver profile hepatic function panel, LFT.

An initial step in detecting liver damage is a simple blood test to determine the level of certain liver enzymes (proteins) in the blood. Under normal circumstances, these enzymes mostly reside within the cells of the liver.

But when the liver is injured for any reason, these enzymes are spilled into the blood stream. Enzymes are proteins that are present throughout the body, each with a unique function.

Enzymes help to speed up (catalyze) routine and vital chemical reactions in the body.

Liver function tests (also known as a liver panel) are blood tests that measure different enzymes, proteins, and other substances made by the liver. These tests check the overall health of the liver.

Following are the different substances often tested at the same time on a single blood sample for LFT:

  • Albumin a protein made in the liver
  • Total protein. This test measures the total amount of protein in the blood.
  • ALP ALP(alkaline phosphatase), ALT (alanine transaminase), AST (aspartate aminotransferase), and gamma-glutamyl transferase (GGT). These are different enzymes made by the liver.
  • Bilirubin, a waste product made by the liver.
  • Lactate dehydrogenase (LD), an enzyme found in most of the body’s cells. LD is released into the blood when cells have been damaged by disease or injury.
  • Prothrombin time (PT), a protein involved in blood clotting.

If levels of one or more of these substances are outside of the normal range, it may be a sign of liver disease.


Aminotransferase Enzymes (ALT, AST)

The aminotransferase enzymes catalyze chemical reactions in which an amino group from one amino acid (amino acids are building blocks of proteins) is transferred from a donor molecule to a recipient molecule, hence, the names “aminotransferases.”

Medical terms can sometimes be confusing, as is the case with these enzymes because they have interchangeable names that commonly appear in both medical and non-medical articles. For example:

  • Another name for aminotransferase is transaminase.
  • The enzyme aspartate aminotransferase (AST) is also known as serum glutamic oxaloacetic transaminase (SGOT).
  • Alanine aminotransferase (ALT) is also known as serum glutamic pyruvic transaminase (SGPT).

Briefly, AST = SGOT and ALT = SGPT; they are enzymes produced by the liver and other types of cells.

Alanine aminotransferase (ALT)

Alanine aminotransferase (ALT) is present primarily in liver cells. In viral hepatitis and other forms of liver disease associated with hepatic necrosis, serum ALT is elevated even before the clinical signs and symptoms of the disease appear.

Although serum levels of both aspartate aminotransferase (AST) and ALT become elevated whenever disease processes affect liver cell integrity, ALT is a more liver-specific enzyme.

Serum elevations of ALT are rarely observed in conditions other than parenchymal liver disease. Moreover, the elevation of ALT activity persists longer than does AST activity.

Aspartate Aminotransferase (AST)

Aspartate aminotransferase (AST) is a transaminase enzyme that catalyzes the conversion of aspartate and alpha-ketoglutarate to oxaloacetate and glutamate.

The AST enzyme was formerly known as serum glutamate oxalate transaminase (SGOT) and is present in all tissues except bone, with highest levels in liver and skeletal muscle. Concentration of AST is elevated after bruising, trauma, necrosis, infection, or neoplasia of liver or muscle.

The AST enzyme is found in cerebrospinal fluid, exudates, and transudates in proportion to the amount of cellular damage.

Where AST (aspartate aminotransferase) and ALT (aminotransferase enzymes) are Found

AST (SGOT) is normally found in a variety of tissues including the liver, heart, muscle, kidney, and brain. It is released into the serum when any one of these tissues is damaged.

For example, the AST level in serum is elevated in heart attacks or with a muscle injury. It is, therefore, not a highly specific indicator of liver injury as its elevation can occur as a result of other injured tissues.

ALT (SGPT) is, by contrast, normally found largely in the liver. This is not to say that it is exclusively located in the liver, but that is where it is most concentrated.

It is released into the bloodstream as the result of liver injury. Thus, it serves as a fairly specific indicator of liver status.

High (Elevated) Levels of AST and ALT

Following are the normal ranges of AST and ALT:

  • The normal range of values for AST (SGOT) is about 5 to 40 units per liter of serum (the liquid part of the blood).
  • The normal range of values for ALT (SGPT) is about 7 to 56 units per liter of serum.

The ranges of AST and ALT numbers may differ slightly depending on the technique and protocols used by different laboratories worldwide. However, normal reference ranges are routinely provided by each laboratory and printed with each patient’s individual report.

AST (SGOT) and ALT (SGPT) are reasonably sensitive indicators of liver damage or injury from different types of diseases or conditions, and collectively they are termed liver tests or liver blood tests.

However, it must be emphasized that higher-than-normal levels of these liver enzymes should not be automatically equated with liver disease. They may mean liver problems or they may not.

For example, elevations of these enzymes can occur with muscle damage. The interpretation of elevated AST and ALT results depends upon the entire clinical evaluation of an individual, and so it is best done by physicians experienced in evaluating liver disease and muscle disease.

Moreover, the precise levels of these liver enzyme tests do not correlate well with the extent of liver problems or the prognosis (outlook). Thus, the exact levels of AST (SGOT) and ALT (SGPT) cannot be used to determine the degree of liver disease or predict the future prognosis for liver function.

For example, patients with acute viral hepatitis-A may develop very high AST and ALT levels (sometimes in the thousands of units/liter range), but most patients with acute viral hepatitis-A recover fully without residual liver disease.

Again, patients with chronic hepatitis-C infection typically have only a little elevation in their AST and ALT levels while having substantial liver injury and even advanced scarring of the liver (cirrhosis) from ongoing minor inflammation of the liver.

Types of Liver Function Tests (LFT)

A liver function test is one of a group of tests that check levels of certain enzymes and other proteins in the blood. Some of the tests look for enzymes that are found in liver disease  and when the liver is damaged. Others check that the liver is working properly, the way it should.

Following are some of the blood tests reflect liver function:

  • Coagulation panel (prothrombin time or PT, and international normalized ratio or INR): These tests measure blood’s ability for normal clotting and prevention of bleeding and bruising. This is the function of certain proteins called clotting factors that normally are produced in the liver. Normal values are about 9.5 to 13.8 seconds.
  • Albumin level (hypoalbuminemia): Albumin is a very common protein found in the blood with a variety of functions. It also is produced only in the liver, and if its levels are lower than normal it can be suggestive of chronic liver disease or liver cirrhosis. Of note, many conditions other than liver disease also may cause low albumin levels. Normal values are about 3.5 to 5 g/dL.
  • Bilirubin: This molecule is a byproduct of the routine destruction of red blood cells occurring in the liver. It is normally released as bile in the feces. Elevation of the bilirubin can suggest liver dysfunction. However, other conditions with increased destruction of red blood cells also can cause elevated bilirubin levels despite normal liver function. Normal values are about 0.1 to 1.0 mg/dL.
  • Platelet count: Low platelet count (thrombocytopenia) has many causes, one of which can be advanced liver disease. Normal platelet counts are about 150,000 to 400,000 per (µL).
  • Glucose: Glucose level is maintained in the body by a variety of mechanisms. The liver can release glucose in the blood for nourishment of other cells in case of starvation with insufficient oral intake of glucose. This process, called gluconeogenesis, is another major function of the liver. In advanced liver disease, this function of the liver can be compromised leading to unusually low glucose levels in the absence of adequate oral intake. Again, a large number of patients with liver cirrhosis become glucose intolerant and develop diabetes.
  • GGT (Gamma-glutamyl transpeptidase): This enzyme is thought to indicate possible liver damage; the higher the abnormal level, the more likely there is liver damage. Normal levels of GGT are about 9 to 48 U/L.
  • ALP (alkaline phosphatase): The liver synthesizes the highest amounts of this enzyme so high levels in the blood may suggest liver injury among other causes. Normal levels of ALP are about 45 to 115 U/L.
  • LD or LDH (Lactate dehydrogenase): This enzyme may be elevated in many types of diseases, including liver disease. Normal levels are about 122 to 222U/L.



Reasons for Abnormal Liver Tests

Abnormal liver tests may be detected a variety of liver conditions in the blood. Some of those are the following:

  • Mild to moderate elevations of the liver enzymes are common. They are often unexpectedly encountered on routine blood screening tests in otherwise healthy individuals. The AST and ALT readings in such cases are usually between twice the upper limits of normal and several hundred units/liter. One of the most common causes of mild to moderate elevations of these liver tests is a condition referred to as fatty liver disease (steatohepatitis or hepatic steatosis). In the United States, the most frequent cause of fatty liver disease is alcohol abuse.  

Alcoholic fatty liver disease only happens in people who are heavy drinkers, especially those who have been drinking for a long period of time.

The risk is higher for heavy drinkers who are women, have obesity, or have certain genetic mutations.

Other causes of fatty liver include diabetes mellitus, and obesity. Fatty liver disease tests are composed of several tests including blood tests, CT and/or MRI scan tests, and in some patients, a liver biopsy.

  • Hepatitis-B and Hepatitis-C are other causes of chronic mild to moderate liver enzyme elevation. In these conditions, ALT and AST may be only slightly high and the degree of abnormality in liver function tests can indicate the degree of injury.
  • Chronic and acute alcohol use also can commonly cause abnormal liver blood tests. In alcoholic hepatitis, the range of liver tests can vary greatly. In chronic alcohol liver disease or alcoholic cirrhosis, slight elevation of ALT and AST may be observed, whereas, in acute alcoholic hepatitis, high liver enzyme numbers are often seen.
  • Some medications can be responsible for a mild to moderate increase in the liver enzyme tests.

Medications that can cause increased liver enzyme tests (AST and ALT) levels

Following are examples of some of the common medications with potential liver toxicity:

Pain Relief Medications

  • Aspirin
  • Acetaminophen (Tylenol)
  • Ibuprofen (Advil, Motrin)
  • Naproxen (Naprosyn, Naprelan, Anaprox, Aleve)
  • Diclofenac (Voltaren, Cataflam, Voltaren-XR)
  • Phenylbutazone (Butazolidine)

Anti-seizure Medications

  • Phenytoin (Dilantin)
  • Valproic acid ( Depakote)
  • Carbamazepine (Tegretol)
  • Phenobarbital


  • Tetracyclines (Achromycin)
  • Sulfonamides
  • Isoniazid (Nydrazid, Laniazid)
  • Sulfamethoxazole (Gantanol)
  • Trimethoprim(Trimpex; Proloprim, Primsol)
  • Nitrofurantoin (Macrodantin, Furadantin, Macrobid)
  • Fluconazole (Dilflucan) and other anti-fungals

Cholesterol Lowering Drugs (Statins)

  • Lovastatin (Mevacor, Altocor)
  • Pravastatin (Pravachol)
  • Atorvastatin (Lipitor)
  • Fluvastatin (Lescol)
  • Simvastatin (Zocor)
  • Rosuvastatin (Crestor)
  • Niacin

Cardiovascular Drugs

  • Amiodarone (Cordaone)
  • Hydralazine (Apresoline)
  • Quinidine (Quinaglute, Quinidex)

Other Drugs

  • Antidepressant drugs of the tricyclic type

With drug-induced liver enzyme abnormalities, the enzymes usually normalize weeks to months after stopping the medications. Typically, the physician will want to monitor the patient’s liver enzymes over time to confirm that the values are normalizing.

Diseases that can cause very high AST or ALT levels

AST and ALT serum levels in some liver conditions can range anywhere from ten times the upper limits of normal to thousands of units/liter.

The highest levels of AST and ALT are found with disorders that cause rapid death of numerous liver cells (extensive hepatic necrosis). Although this degree of liver enzymes elevation is not common, it can occur in such conditions as:

  • Acute viral hepatitis A or B
  • Profound liver damage inflicted by toxins as from an overdose of acetaminophen (brand-name Tylenol) or mushroom poisoning
  • Prolonged collapse of the circulatory system (shock) when the liver is deprived of fresh blood providing oxygen and nutrients

Also, very high AST and ALT levels can be a result of severe muscle diseases.

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Standard liver tests – PMC

Clin Liver Dis (Hoboken). 2016 Jul; 8(1): 13–18.

Published online 2016 Jul 26. doi: 10.1002/cld. 562

, M.D.
and , M.D.



Author information Article notes Copyright and License information Disclaimer

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autoimmune hepatitis
alanine aminotransferase
antimitochondrial antibodies
alkaline phosphatase
aspartate aminotransferase
drug‐induced liver injury
endoscopic retrograde cholangiopancreatography
γ‐glutamyl transpeptidase; LIT, liver injury test
Model for End‐Stage Liver Disease
magnetic resonance cholangiopancreatography
nonalcoholic steatohepatitis
primary biliary cholangitis
upper limit of normal

The liver is the largest organ in the body and arguably the most important organ for protein production and detoxification, both of which are facilitated by a myriad of enzymes. Both the detection of enzymes released from liver cells and proteins produced by the liver and released into the blood can be used to analyze liver health.

Standard liver tests (Tables and ) that assess injury to the liver include alanine aminotransferase (ALT), aspartate aminotransferase (AST), and alkaline phosphatases (APs). The excretory function of the liver can be estimated by bilirubin and the metabolic function of the liver by clotting tests and albumin.

Table 1

Standard Liver Tests, Their Sources of Origin, and Abnormalities

ParameterOriginAssociated Disease
ASTLiver, skeletal muscle, cardiac muscle, red blood cells, brain, pancreas, lungsHepatocellular injury of any cause, myopathies, myocardial infarct, hemolysis
ALTLiver, kidneys, skeletal muscleHepatocellular injury of any cause, myopathies
APLiver, bone, placenta, kidneys, intestinesCholestatic liver disease; sarcoidosis; pregnancy; lymphoma; bone, kidney, and intestinal diseases
γ‐Glutamyl transferaseBiliary epithelial cells, kidneys, pancreas, prostateBiliary or pancreatic disease, myocardial infarct, renal diseases, chronic lung disease, diabetes
Conjugated bilirubinHemolysis, insufficient excretion from the liverSevere liver injury from any cause Rotor syndrome, Dubin‐Johnson syndrome
Unconjugated bilirubinHemolysisHemolysis, Gilbert syndrome, Crigler‐Najjar syndrome
AlbuminProduced in hepatocytesLow in nephrotic syndrome, malnutrition, protein‐losing enteropathy
Prothrombin timeClotting factors produced in hepatocytesProlonged in liver disease, vitamin K deficiency, fat malabsorption, pancreatic insufficiency

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Table 2

Elevation of Liver Chemistries With Liver Diseases

TestHepatocellularCholestaticHalf‐life (t
AST+++N/+17 hours
ALT+++N/+47 hours
APNormal/mild++++7 days
gGT++/+++++++26 days (for abstinence)
Total bilirubinN/++N/+++Depends on albumin binding
Albumin++ (chronic)N20 days
Prothrombin time++N

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Tests that describe injury of the liver such as aminotransferases and AP have historically been mislabeled liver injury tests (LIT). In contrast, standard tests such as albumin, bilirubin, and prothrombin time are useful in evaluating liver function.

The pattern of elevation of the different enzymes can be used to discriminate hepatocellular from cholestatic or mixed injury; AST and ALT are more elevated in patients with hepatocellular injury, whereas AP and γ‐glutamyl transpeptidase (gGT) are more elevated in cholestatic injury.

Normal values for laboratory results are defined as those found in 95% of a population. Thus, 2.5% of a population will be above and below the normal values, respectively. But being outside the normal does not immediately reflect illness; that is, a bilirubin level below normal has no clinical consequences. Contrarily, being within the normal value does not necessarily reflect a healthy state. In that regard it has been suggested to use an upper limit of 19 and 30 U/L for ALT for women and men, respectively,1 to reflect healthy values. This also fits the observed increased mortality in individuals with ALT values that are normal but above the healthy range. 2 Thus, liver transaminases likely will be described as healthy (≤19 U/L for women and ≤30 U/L for men) and normal values (i.e., <65 U/L). The normal values will depend on the specific laboratory population, thus limiting standardization.

For some assessments such as drug safety, the times upper limit of normal (ULN) is established to define safety margins. Substituting the healthy range values for normal range value will therefore need to be carefully addressed in the future.

Mild abnormalities in liver‐related tests may warrant repeat testing before a more extensive workup is initiated. Abnormal liver chemistries may occur in 1% to 4% of the asymptomatic population.3, 21

Transaminases are involved in transferring the amino groups of aspartate and alanine to ketoglutaric acid. Although ALT is more liver specific, elevated ALT levels are also reported in myopathies (Table ).4, 5

Table 3

Disease Association According to Aminotransferases Elevation Pattern

AST PredominantALT Predominant
Alcohol‐related liver injuryChronic hepatitis C
CirrhosisChronic hepatitis B
HemolysisAcute viral hepatitis (types A‐E, herpes simplex virus, Epstein‐Barr virus, cytomegalovirus)
Thyroid diseaseHemochromatosis
Strenuous exerciseMedications/toxins
Autoimmune hepatitis
Wilson’s disease
Celiac disease

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Hepatocyte injury results in altered cell membrane permeability causing the excessive leakage of transaminases. Periportal hepatocytes (zone 1) have relatively more ALT, whereas the hepatocytes near the central vein (zone 3) have more AST (Fig. ). Thus, causes of hepatic inflammation that are predominantly involving zone 1 such as viral and autoimmune hepatitis result in predominantly ALT elevation. In contrast, ischemic or toxic insults are more likely to involve zone 3, causing a predominance of AST elevation. AST/ALT ratio, also known as De Ritis ratio, is useful in assessing various liver diseases.6 In alcoholic hepatitis, AST is usually higher than ALT, with the AST/ALT ratio reaching 2:1. In acute viral hepatitis, ALT levels are usually higher than AST. High AST/ALT ratio (>1.5) in acute viral hepatitis may be indicative of potential fulminant course.9 AST/ALT ratio greater than 1.0 in chronic liver diseases may be indicative of advanced fibrosis.8, 9 AST and ALT are also used together with platelets to assess the likelihood of advanced liver fibrosis and are part of the aspartate aminotransferase‐to‐platelet ratio index (APRI) and FIB‐4 score:

  • APRI: AST level (/ULN) / platelet counts (109/L) × 100

  • FIB‐4 score: [age (years) × AST (U/L)]/{platelets (109/L) × [ALT (U/L)]1/2}.

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Zone 1 has more ALT than AST, and zone 3 has more AST than ALT. Autoimmune and viral hepatitis predominantly involve zone 1 (ALT > ALT). Ischemic and toxic events, heart failure, and Budd‐Chiari syndrome predominantly involve zone 3 (AST > ALT). AP is mostly present on basolateral membrane of hepatocytes lining the bile canaliculi. Reproduced from PLoS Biology. Copyright 2005, Frevert et al.

Aminotransferases are normal or only mildly elevated in obstructive jaundice except in acute phase of biliary obstruction caused by the passage of gallstone into the common bile duct.10 In this case, aminotransferases may reach values greater than 1000, decreasing quickly, with liver test rapidly evolving into those of typical cholestasis or normalizing completely.

Aminotransferases levels also vary with age, sex, race, and body mass index.11 Levels are found to be higher in obese patients and lower in dialysis patients,12 whereas ALT levels are noted to decline with weight loss. 13 AST levels are 15% higher in African American males as compared with Caucasians.11 Some individuals may have asymptomatic AST elevation caused by a defect in clearance of the enzyme.14 Transaminases levels can be very high in patients with acute viral hepatitis, drug‐induced liver injury, hepatic ischemia, and Budd‐Chiari syndrome (Fig. ). In asymptomatic patients with no underlying disease, mild aminotransferase elevation for more than 6 months warrants further investigation.22

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Typical AST elevation and De Ritis ratios for different kinds of liver diseases.

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Algorithms for evaluation of elevated aminotransferases (A), AP (B), and bilirubin (C), respectively. Abbreviations: AIH, autoimmune hepatitis; AMA, antimitochondrial antibodies; DILI, drug‐induced liver injury; ERCP, endoscopic retrograde cholangiopancreatography; MRCP, magnetic resonance cholangiopancreatography; NASH, nonalcoholic steatohepatitis; PBC, primary biliary cholangitis.

AP is the standard liver test reflecting cholestasis and can be complemented by gGT. gGT is part of a typical liver panel in some countries, whereas in the United States the standard liver test usually includes only AST, ALT, and AP. Because gGT is diffusely located in endoplasmic reticulum of bile ductal cells, its elevation is less specific for cholestasis but supports the suspicion that an elevated AP is liver derived as opposed to being of extrahepatic origin (Tables and ).15

Table 4

Elevated AP

Bile duct obstructionBone disease
Benign intrahepatic recurrent cholestasisPregnancy
Primary biliary cholangitisChronic renal failure
Primary sclerosing cholangitisLymphoma and other malignancies
MedicationsCongestive heart failure
Infiltrating diseases of the liverChildhood growth
Hepatic metastasis

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Elderly individuals older than 60 years, especially women, may have a mildly elevated AP. 16 Individuals with blood types O and B may have an elevation of the serum AP after eating a fatty meal because of the influx of intestinal AP into circulation.7 AP can also be nonpathologically elevated in children and adolescents undergoing rapid bone growth16 and in women late in normal pregnancies because of the influx of placental AP.17

Bilirubin, albumin, and prothrombin time are standard tests to evaluate the liver function.

Bilirubin is the result of enzymatic breakdown of heme. Bilirubin is conjugated in the liver, resulting in water solubility. The conjugated bilirubin is then secreted into the bile. In healthy individuals, conjugated bilirubin comprises a small proportion of total bilirubin.18

In adults, unconjugated bilirubin elevation is most often of extrahepatic origin, mainly caused by hemolysis. In the absence of hemolysis, isolated unconjugated hyperbilirubinemia in an otherwise healthy patient should raise the suspicion for Gilbert syndrome. Up to 5% of the population has Gilbert syndrome, which is due to partial defects in uridine 5′‐diphosphate‐glucuronosyltransferase, the enzyme that conjugates bilirubin.19 Crigler‐Najjar syndrome is a rare cause of unconjugated hyperbilirubinemia.

In adults, conjugated hyperbilirubinemia is almost always a sign of biliary obstruction or impaired hepatic function. Two rare hereditary conditions cause defects in the secretory mechanism, Dubin‐Johnson syndrome and Rotor syndrome, which result in elevated conjugated bilirubin.

Total serum bilirubin with increased prothrombin time correlates with poor outcomes in alcoholic hepatitis.18 Both are also critical components of Model for End‐Stage Liver Disease (MELD) score and Child‐Pugh score.

Serum albumin is exclusively synthesized by hepatocytes, but the long half‐life of albumin makes it difficult to interpret in the setting of acute liver injury. In chronic liver disease, albumin is the first of the three standard liver function tests to decline in advancing liver cirrhosis, before increase in bilirubin or prothrombin time. Albumin less than 35 g/dL should raise suspicion for cirrhosis. Differential diagnosis for hypoalbuminemia includes protein malnutrition of any cause, as well as protein‐losing enteropathies, nephrotic syndrome, and chronic infection.

With the exception of factor VIII, all coagulation factors are synthesized in the liver. Because of the short half‐lives of the coagulation factors, these are the best parameters to measure synthetic function of liver in acute conditions. This is most frequently done by prothrombin time determination. Because most clotting factors synthesized in the liver depend on vitamin K, prothrombin time is affected by vitamin K deficiency or use of vitamin K inhibitors. Vitamin K deficiency is seen in patients with chronic cholestasis or fat malabsorption from disease of the pancreas or small bowel. Prothrombin time is a better indicator of hepatic dysfunction than the international normalized ratio (INR),20 despite INR having become a crucial part of the MELD score used for prioritizing liver allocations. In acute and chronic liver disease, prolonged prothrombin time (>5 seconds), which does not respond to parenteral vitamin K, is a poor prognostic sign.

Potential conflict of interest: Nothing to report.

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Biochemical blood test in St. Petersburg, Novgorod, Staraya Russa

Biochemical blood test (BAC) is one of the most informative tests that gives an idea about the work of the kidneys, liver, gallbladder, pancreas, other organs, lipid, protein and carbohydrate metabolism, the balance of microelements.


Total bilirubin

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Aspartate aminotransferase (AST)

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LHC can be prescribed by any doctor, because with each disease it is important to see the big picture. For preventive purposes, blood biochemistry is done once a year, during pregnancy – in the 1st and 3rd trimesters with a normal course and more often – with ailments and complaints of a woman about her well-being.

Test indications

  • complaints of malaise;
  • any disease;
  • assessment of the state after therapy;
  • preventive examination.

Blood chemistry tests

During a biochemical analysis, the blood sugar, urea, total lipids, low and high density cholesterol, triglycerides, total bilirubin, total protein, AsAt, AlAt enzymes, lipase, amylase, gamma-GTP and other indicators are determined. Each of the indicators may indicate the normal operation of an organ, system, or a deviation from the norm.

It should be remembered that blood biochemistry is a primary diagnosis, an assessment of a person’s overall health. Its results can only be interpreted by an experienced specialist. According to the indicators of the BAC, the doctor prescribes special tests if there are suspicions of a disease or pathology of organs.

Biochemical analysis of blood a large number of tested items. Next, we will talk about the main ones.

Further in the text are the norms of the research, WHICH ARE INFORMATIONAL CHARACTER. In all laboratories, the norms, units of measurement may differ, as well as THEY DEPEND on the gender and age of the patient. BE CAREFUL!

Specific proteins and inflammatory markers

More than 20 plasma proteins are called specific proteins and markers of inflammation, the concentration of which indicates the development of acute inflammation or tissue damage.

C-reactive protein

CRP is one of the most sensitive markers of acute inflammation and tissue damage. It appears in the blood serum and rapidly increases in volume when:

  • various inflammations;
  • diseases of the gastrointestinal tract;
  • parasitic, viral, bacterial infections;
  • systemic rheumatic diseases;
  • metastases of cancerous tumors;
  • tissue damage, including acute myocardial infarction;
  • neonatal sepsis;
  • meningitis;
  • tuberculosis;
  • burns;
  • taking oral contraceptives, estrogens.

According to the above list, it is clear that the indicator has a low specificity, therefore, with its high rates, narrower studies are immediately prescribed if the reason for the increase is unknown.

The CRP indicator is used to determine the success of therapy: if the treatment gives a result, the protein returns to normal after 6-10 days

Eosinophilic cationic protein (ECP)

ESR rises when:

  • atopic bronchial asthma;
  • allergic rhinitis;
  • atopic dermatitis;
  • food allergies;
  • helminthiasis;
  • acute respiratory infections;
  • malignant diseases with activation of eosinophils;
  • taking certain medications.

Rheumatoid factor

Rheumatoid factor is a protein produced by the human immune system. An increase in the rate of the RF may indicate rheumatoid arthritis, Sjögren’s syndrome, chronic infections of a bacterial, viral, parasitic nature, some types of oncology, diseases of the kidneys, liver, and lungs.


The concentration of myoglobin increases if the myocardium or skeletal muscles are damaged. Normally, its concentration is not determined in the laboratory – so little myoglobin is contained in the blood of a healthy person, from 0 to 70 mcg / l.

Troponin I

Tn I is a heart muscle protein that enters the bloodstream during myocardial infarction. It is one of the most sensitive and specific indicators for damage to the heart muscle. After a heart attack, after about 3 hours, the level of Tn I in the blood rises significantly and remains so for up to 14 days.

Creatine kinase MB

KK-MB is a cell enzyme that is used as a specific and sensitive indicator of myocardial damage.

CK-MB is located almost in its entirety in the heart muscle, therefore its content in the bloodstream is negligibly small. If it increases, then the likelihood of acute heart attack, recurrent heart attack and other pathological processes associated with the heart is high.


NT-proBNP is a protein of the left ventricle of the heart. A change in its level may indicate heart failure, its severity. The level of this protein also evaluates the effectiveness of heart failure therapy.

The norm for people under 75 years old is 0-125 pg / ml, over 75 years old – up to 450 pg / ml.

Antistreptolysin-O (ASLO)

ASLO is a marker of streptococcal infection. Its increase is caused by angina, scarlet fever, chronic tonsillitis, acute glomerulonephritis, streptococcal pyoderma.


Procalcitonin rises in the blood during bacterial infections, sepsis, septic shock, multiple organ failure, and some other serious conditions.


Electrolytes include chlorine, sodium, and potassium. They play an important role in metabolic processes, maintain the level of acidity, water balance. The level of electrolytes is the most important characteristic of human health, an indicator of the functionality of the heart and kidneys.

Abnormalities in kidney function, heart disease, diabetes mellitus, pathologies and disorders in the functioning of muscles and the nervous system lead to deviations from the norm. If the electrolyte imbalance is not stabilized by eliminating its causes, the person will experience dizziness, convulsions, and irregular heartbeats. In especially advanced cases, an electrolyte imbalance leads to death.

Lipid metabolism

The LHC shows the level of fats and allows you to assess the risk of occurrence, development of heart and vascular diseases. During testing, the level of triglycerides, cholesterol – total, LDL, HDL is checked.


Triglycerides grow in diabetes, heart and vascular pathologies, pregnancy; decrease in case of disturbances in the functioning of the thyroid gland, at the terminal stage of liver damage, if a person eats poorly, monotonously.


  • HDL (“good cholesterol”). Participates in the processing and removal of fats from the body. If the values ​​are high, then the risk of formation of vascular plaques decreases. The norm is 1.03–1.55 mmol / l.
  • LDL (“bad cholesterol”). Normally – 0-3.3 mmol / l – it is necessary for the body. Exceeding the norm threatens the development of atherosclerosis.
  • Total (composed of HDL and LDL). The norm indicator is 5.2 mmol / l. A decrease against the norm leads to psychophysiological disorders, reproductive dysfunction. Elevated levels can cause diabetes, atherosclerosis.

Carbohydrate metabolism

During the LHC, glucose and fructosamine levels are examined. An increase in their level can occur with diabetes mellitus, a decrease in pancreatic tumors, when taking insulin.

  • the norm for glucose is 3.3-5.5 mmol / l;
  • the norm for fructosamine is up to 285 µmol / l.


During the LHC, the level of bilirubin is set – total (yellow), direct, indirect.

  • General. Normally – 3.4-17.1 µmol / l, an increase occurs in pathologies, liver diseases, disruption of its work.
  • Straight. Normal – up to 7.9 µmol/l, an increase indicates pathologies of the liver, biliary tract.
  • Indirect . Its indicators are calculated, depend on direct and total bilirubin. An increase in indirect bilirubin is often associated with anemia, malaria.


Serum iron is one of the most important indicators of health. It transports and deposits oxygen, participates in hematopoiesis, and is part of many proteins and enzymes. Especially carefully you need to monitor the level of iron in children, adolescents, pregnant and lactating women, the elderly, those who experience high physical exertion, suffer from chronic bleeding.
A decrease in the level of iron occurs with malnutrition, heavy blood loss, non-assimilation of iron, and an increased need for it.


1. Liver tests. The standard set of LHC indicators includes the so-called. “liver tests” – ASAT, ALT. Changes in the norm can signal diseases, pathologies of the liver, heart, inflammation and infections.

  • The AST norm is up to 31 U/l in women, up to 37 U/l in men.
  • The ALT norm is up to 34 U/l in women, up to 45 U/l in men.

2. Amylase – digestive juice enzyme. An increase in its level occurs in acute, chronic pancreatitis, other diseases (including tumors) affecting the pancreas.

  • Amylase rate – 28-100 U / l.

3. Pancreatic amylase – P-type amylase. An increase in the level of P-type amylase occurs when the pancreatic duct is blocked by a tumor, stone, and in some other cases.

4. Creatine kinase (CK) is an enzyme that provides energy for muscle contraction. In the blood, it is present in different isomers. By increasing the concentration of individual isomers, an assumption is made about damage to muscles, myocardium, and oncological diseases.

5. L ipaza — digestive juice enzyme. A change in the norm indicates problems with the pancreas.

6. Vitamins . The standard BAC determines the concentration of vitamin B12. It is necessary, first of all, for hematopoiesis. An increase in the level of B12 occurs with diseases of the kidneys, liver, leukemia, a decrease in vegetarianism, inflammation of the gastrointestinal tract, and parasitic infections. The norm of vitamin – from 208 to 963.5 pg/ml. The BAC may include a test for the content of vitamins of group D. Deficiency of this vitamin is experienced by up to 60% of people around the world. Vitamin deficiency is expressed in rickets (children), muscle weakness, pain in the pelvic bones, lower back, legs. With vitamin intoxication (uncontrolled intake of vitamin-containing complexes), headaches, nausea, vomiting, a metallic taste in the mouth, acute pancreatitis, nephro- and arteriolocalcinosis occur.

  • The norm for vitamin D2 is 0. 8-7 ng / ml, for vitamin D3 – 2.2-42.6 ng / ml.

Rules for preparing for analysis and passing the LHC

Many factors affect blood counts: food (including drinking water), habits, physical and mental state, bathing, medications, alcohol, smoking, etc. Therefore, to obtain accurate data, several requirements must be met:

  • donate blood on an empty stomach, from 8 to 11 am (all laboratory indicators are calculated for this time, they change over the course of the day). Even water is recommended not to drink whenever possible. At least 8 hours should have passed since the last meal, ideally 12 hours;
  • the day before, and preferably a few days before, you should give up heavy, fatty, fried foods, strong tea, alcohol, carbonated drinks, and other foods that can change the functioning of the liver, kidneys, pancreas;
  • a day before the analysis, avoid physical, psychological overload, do not visit the bathhouse, solarium, do not do x-rays, fluorography, physiotherapy, ultrasound;
  • a day before the analysis, refrain from taking medications. If this is not possible, you need to inform the doctor and follow his recommendations;
  • 2 hours before donating blood, do not smoke;
  • just before donating blood, sit for 15-20 minutes to calm down, stabilize breathing, pressure.

Important! The rules for donating blood for the LHC may differ in different laboratories, therefore, before testing, it is necessary to clarify them.

How the study is done

For research, blood is taken from a vein.

Where to take a biochemical blood test

Analyzes can be taken in any subdivision of JSC “SZTsDM” that is most conveniently located to you geographically. And it is also possible to order a nurse’s visit to your home or office, the departure is FREE, only the collection and tests are paid in accordance with the presented price list and with the preservation of all cumulative discounts, if any.

How to decipher a biochemical blood test: the norm of indicators



November 11, 2020

This is a quick way to check your liver, kidneys, blood sugar and metabolic quality.

Why do we need a biochemical blood test

The meaning of a biochemical blood test (BAC) can be explained in a nutshell. If a general blood test (CBC) gives an idea of ​​the state of the body as a whole, then the BAC adds details – it tells whether specific organs and systems are healthy.

A blood chemistry test helps detect liver, kidney, diabetes and other ailments.

In addition, the LHC allows you to find out if everything is in order with the level of sugar in the blood, metabolism and what important vitamins, micro and macro elements, hormones, enzymes the body lacks for normal work.

What your blood chemistry shows

The technician will take a few milliliters of blood from your vein. This must be done on an empty stomach – 8-12 hours after the last meal. The sample taken is then examined for several key components. They are divided into groups.


Or blood sugar. Glucose is a source of energy for body cells. The body regulates its amount in the blood with various hormones (such as insulin) and enzymes. If there is too much or too little sugar, then something is wrong with the endocrine or excretory system.


  • Albumin . It is a protein that is produced by the liver. Blood plasma is approximately 60% albumin.
  • Total protein . There are several dozen different proteins in the blood. Total protein is the average total of them.
  • Specific proteins . These are separate types of blood proteins, a change in the level of which may be associated with serious diseases. Specific ones include, in particular, C‑reactive protein (it signals an acute inflammatory process in the body), ferritin (needed for normal absorption of iron), myoglobin (creates the necessary supply of oxygen in muscles, including the heart), rheumatoid factor (antibodies that are produced only in case of serious diseases: infectious, muscular and connective tissues, autoimmune, oncological and others). Analysis for specific proteins is not always included in the standard LHC. If the doctor wants to find out the content of a particular substance in the blood, he will write about it in the direction for the study.


The so-called lipid panel allows you to check the level of various types of cholesterol.

  • High density lipoproteins (HDL) . This is the so-called good cholesterol, which removes harmful substances from the blood and helps the liver break them down.
  • Low density lipoproteins (LDL) . We are talking about “bad” cholesterol, which causes the formation of plaques in the vessels and increases the risk of cardiovascular disease.
  • Total cholesterol . The sum of the values ​​of “good” and “bad”.

Liver tests

This is the name given to the assessment of the level of certain enzymes associated with the condition of the liver.

  • Total bilirubin . It is an orange-yellow pigment that is formed when hemoglobin is broken down. Bilirubin is toxic, so normally the liver quickly removes it from the body. But if hemoglobin is destroyed too actively or the liver cannot cope with normal volumes of bilirubin, the level of pigment in the blood rises sharply. This is often manifested externally – yellowing of the skin and whites of the eyes (jaundice).
  • Alanine aminotransferase (AlAt, ALT) . Liver enzyme necessary for amino acid metabolism. Its level rises with liver damage.
  • Aspartate aminotransferase (AsAt, AST) . Another enzyme that is released into the blood during serious disorders in the liver.
  • Alkaline Phosphatase . This is an enzyme involved in phosphorus metabolism. Its increase is also a marker of liver problems.

Kidney tests

  • Creatinine . This is a waste product that is formed in the muscles. It is excreted from the blood by the kidneys, so the level of creatinine is a good indicator of the work of this paired organ.
  • Uric acid . Formed in the liver and again excreted from the blood by the kidneys. If they fail (or, on the contrary, are unhealthy active), the level of uric acid in the blood rises (or falls).
  • Urea . It is also formed in the liver, where proteins are broken down, and excreted from the blood by the kidneys.

Inorganic substances (minerals, electrolytes) and vitamins

  • Calcium . One of the most important minerals in the body. Without it, the normal functioning of muscles, nerves, and heart is impossible. In addition, it is critical for bone development and repair.
  • Sodium . Responsible for the transmission of nerve impulses and helps to absorb calcium.
  • Magnesium . Like sodium, it is actively involved in the transmission of nerve impulses.
  • Chlorine . Helps to regulate the amount of fluid in the body and maintain acid-base balance.
  • Potassium . Critical to the normal functioning of the heart.
  • Iron . Necessary for the delivery of oxygen to organs and tissues.
  • Phosphorus . The nervous, muscular and skeletal systems are in great need of it.
  • Folic acid . Participates in a huge number of processes in the body – from the absorption of amino acids and glucose to the production of blood.
  • Vitamin B12 . It is essential for the production of red blood cells – erythrocytes.

What are the norms of blood parameters in LHC

The form with the results of a biochemical blood test, as a rule, is a table of three columns. The first contains the name of the indicator, the second contains the range of its normal values, and the third contains your result.

To check the norm, first of all, be guided by the numbers indicated on the form issued to you. The fact is that laboratories conduct tests on different reagents and under different conditions. Therefore, the optimal value ranges may vary slightly depending on the organization that processed your analysis. Only one thing is important for you: to check whether the result falls within the limits of the norms established by a particular laboratory.

The figures below are indicative for the most common indicators.

904 55

Indicator Norm for an adult
Glucose 3, 9-5.6 mmol/l
Albumin 34-54 g/l
Total protein 60–83 g/l
HDL cholesterol 40 mg/dl and above for men; 50 mg/dl and above for women
LDL cholesterol Less than 100 mg/dL
Total cholesterol 125–200 mg/dL
Total bilirubin 1.71–20.5 µmol/l
Alat , ALT 4–36 U/L
AsAt, AST 8–33 U/L
Alkaline Phosphatase 20-140 U/L
Creatinine 74 –107 µmol/L
Uric acid 3. 5-7.2 mg/dl
Urea 2.5-7.1 mmol/l
Calcium 90 459

2.2-2.7 mmol/l

How to decipher a biochemical blood test

This can and should be done only by the doctor who issued you the referral for the analysis. For the reason that many different factors affect blood biochemistry.

Thus, an elevated blood glucose level can be both a symptom of prediabetes or diabetes, and a sign that you were irresponsible about the analysis and, let’s say, drank sweet coffee before it.

There are other examples. Elevated liver function tests are a marker of hepatitis and sometimes cirrhosis. But at the same time, ALT and AST can rise if you are being treated for a bacterial infection by taking antibiotics and other medications. A low urea level is a sign of serious liver damage. Or banal malnutrition if you are on a strict diet.

In general, let’s repeat it again. Only the doctor observing you should decipher the LHC.