Liver Function Tests: Understanding Normal Range Liver Enzymes and Their Significance
What are the standard liver function tests. How do liver enzymes indicate liver health. What are the normal ranges for liver enzymes. How can abnormal liver test results be interpreted. What factors can affect liver enzyme levels.
The Importance of Liver Function Tests in Assessing Liver Health
Liver function tests play a crucial role in evaluating the health and functionality of the liver, which is often referred to as the body’s chemical factory. These tests measure various enzymes, proteins, and other substances in the blood that are produced or processed by the liver. By analyzing these markers, healthcare providers can gain valuable insights into liver health, detect potential liver diseases, and monitor treatment effectiveness.
Standard Liver Tests: Key Markers and Their Origins
Several standard liver tests are routinely used to assess liver function and detect potential liver damage. These tests include:
- Alanine aminotransferase (ALT)
- Aspartate aminotransferase (AST)
- Alkaline phosphatase (AP)
- Gamma-glutamyl transferase (GGT)
- Bilirubin (total and conjugated)
- Albumin
- Prothrombin time
Each of these markers originates from different sources within the body and can be indicative of various liver conditions or diseases. For instance, ALT is primarily found in the liver, while AST is present in multiple organs, including the liver, heart, and muscles. Understanding the origin and significance of these markers is essential for accurate interpretation of liver function test results.
Interpreting Liver Enzyme Elevations: Hepatocellular vs. Cholestatic Injury
The pattern of elevation in different liver enzymes can provide valuable information about the nature of liver injury. Hepatocellular injury, which affects liver cells directly, typically results in more significant elevations of AST and ALT. On the other hand, cholestatic injury, which impairs bile flow, is characterized by more pronounced elevations in AP and GGT.
How can healthcare providers distinguish between hepatocellular and cholestatic liver injury? By examining the relative elevations of different enzymes:
- Hepatocellular injury: AST and ALT are markedly elevated, with minimal or no increase in AP and GGT.
- Cholestatic injury: AP and GGT are significantly elevated, with minimal or moderate increases in AST and ALT.
- Mixed injury: Both hepatocellular and cholestatic markers show significant elevations.
This differentiation is crucial for determining the underlying cause of liver dysfunction and guiding appropriate diagnostic and treatment strategies.
Normal Ranges and Healthy Values: Redefining Liver Enzyme Standards
Traditionally, normal ranges for liver enzymes have been defined as values found in 95% of a population. However, recent research suggests that these ranges may not accurately reflect a healthy liver state. Experts now propose using more stringent “healthy” ranges, particularly for ALT:
- Women: ≤19 U/L
- Men: ≤30 U/L
Why is this distinction important? Values within the traditional normal range but above these healthy thresholds have been associated with increased mortality risk. This paradigm shift highlights the need for a more nuanced interpretation of liver enzyme levels, moving beyond the simple dichotomy of normal versus abnormal.
Are there implications for drug safety assessments? Indeed, many pharmaceutical trials use multiples of the upper limit of normal (ULN) to establish safety margins. The adoption of stricter healthy range values may necessitate a reevaluation of these safety thresholds in future clinical trials and drug development processes.
Factors Influencing Liver Enzyme Levels: Beyond Liver Disease
While elevated liver enzymes often indicate liver problems, it’s crucial to recognize that various factors can influence these levels. Some common non-hepatic causes of liver enzyme elevations include:
- Muscle disorders or intense exercise (affecting AST and ALT)
- Bone diseases (impacting AP levels)
- Medications and supplements
- Alcohol consumption
- Obesity and metabolic syndrome
- Thyroid disorders
How can healthcare providers distinguish between liver-related and non-liver-related causes of enzyme elevations? A comprehensive approach is essential, including:
- Detailed medical history
- Physical examination
- Review of medications and supplements
- Assessment of alcohol consumption and dietary habits
- Consideration of other medical conditions
- Additional targeted testing when necessary
Understanding these influencing factors is crucial for accurate interpretation of liver function test results and avoiding unnecessary interventions or missed diagnoses.
The Role of Liver Function Tests in Diagnosing Specific Liver Conditions
Liver function tests can provide valuable clues for diagnosing various liver conditions. Here are some examples of how specific patterns of liver enzyme elevations may suggest certain liver diseases:
- Viral hepatitis: Marked elevations in AST and ALT, often 10-20 times the upper limit of normal
- Alcoholic liver disease: AST/ALT ratio > 2, with moderate elevations in both enzymes
- Nonalcoholic fatty liver disease (NAFLD): Mild to moderate elevations in AST and ALT, typically less than 5 times the upper limit of normal
- Primary biliary cholangitis (PBC): Elevated AP and GGT, with normal or mildly elevated transaminases
- Drug-induced liver injury (DILI): Variable patterns depending on the specific medication, ranging from hepatocellular to cholestatic injury
How can healthcare providers use these patterns to guide their diagnostic approach? While liver function tests alone are not sufficient for definitive diagnosis, they can help narrow down the differential diagnosis and guide further investigations, such as viral serologies, autoimmune markers, or imaging studies.
Monitoring Liver Function: The Importance of Trending and Serial Testing
Single liver function test results provide a snapshot of liver health at a specific moment. However, the true value of these tests often lies in monitoring trends over time. Serial testing can reveal important information about:
- Disease progression or regression
- Treatment effectiveness
- Development of complications
- Recovery from acute liver injury
How frequently should liver function tests be repeated? The optimal interval for repeat testing depends on various factors, including:
- The underlying condition
- The severity of initial abnormalities
- The patient’s clinical status
- Ongoing treatments or interventions
For instance, in cases of acute hepatitis, daily or weekly monitoring may be necessary, while stable chronic liver conditions might require less frequent testing, such as every 3-6 months. Healthcare providers should tailor the monitoring schedule to each patient’s specific needs and clinical context.
The Significance of Liver Enzyme Half-Lives
Understanding the half-lives of different liver enzymes is crucial for interpreting serial test results. For example:
- AST has a half-life of approximately 17 hours
- ALT has a longer half-life of about 47 hours
- AP has a much longer half-life of around 7 days
These differences in half-lives explain why some enzymes may normalize more quickly than others following an acute liver injury. Recognizing these patterns can help healthcare providers assess the timing and progression of liver damage more accurately.
Beyond Enzymes: Other Important Liver Function Parameters
While liver enzymes are essential indicators of liver health, other parameters provide crucial information about liver function and overall liver status. These include:
Bilirubin
Bilirubin is a breakdown product of hemoglobin and is processed by the liver. Elevated levels can indicate various liver or biliary tract problems. There are two types of bilirubin measured in liver function tests:
- Total bilirubin: Includes both conjugated and unconjugated forms
- Direct (conjugated) bilirubin: The form processed by the liver
Elevated conjugated bilirubin typically suggests liver or biliary tract dysfunction, while elevated unconjugated bilirubin may indicate hemolysis or certain genetic conditions like Gilbert’s syndrome.
Albumin
Albumin is a protein produced by the liver that plays crucial roles in maintaining oncotic pressure and transporting various substances in the blood. Low albumin levels can indicate:
- Chronic liver disease
- Malnutrition
- Nephrotic syndrome
- Protein-losing enteropathy
With a half-life of about 20 days, albumin levels reflect long-term liver synthetic function rather than acute changes.
Prothrombin Time
Prothrombin time measures the blood’s clotting ability, which depends on several clotting factors produced by the liver. Prolonged prothrombin time can indicate:
- Severe liver dysfunction
- Vitamin K deficiency
- Use of anticoagulant medications
Unlike albumin, prothrombin time can change rapidly in response to acute liver injury, making it a valuable marker for assessing liver synthetic function in both acute and chronic settings.
Emerging Biomarkers and Advanced Liver Function Tests
While standard liver function tests remain the cornerstone of liver health assessment, research continues to identify new biomarkers and advanced testing methods. Some emerging areas include:
Fibrosis Markers
Non-invasive tests for liver fibrosis are gaining importance in managing chronic liver diseases. Examples include:
- FibroTest: A panel of serum markers
- Enhanced Liver Fibrosis (ELF) test: Combines three direct markers of fibrosis
- Transient elastography (FibroScan): Uses ultrasound technology to measure liver stiffness
Metabolomics and Proteomics
Advanced analytical techniques are being explored to identify novel biomarkers that may provide more specific information about liver health and disease processes. These approaches analyze patterns of metabolites or proteins in blood or urine samples, potentially offering more precise diagnostic and prognostic information.
Genetic Markers
Genetic testing is becoming increasingly relevant in liver disease management. For example:
- HFE gene mutations in hemochromatosis
- PNPLA3 variants in nonalcoholic fatty liver disease
- Alpha-1 antitrypsin deficiency genotyping
These genetic markers can help identify individuals at higher risk for certain liver conditions or guide treatment decisions in specific cases.
How might these emerging biomarkers and advanced tests complement traditional liver function tests? While they offer exciting possibilities for more personalized and precise liver health assessment, it’s important to note that many of these tests are still in the research phase or have limited availability. As research progresses, integrating these novel approaches with standard liver function tests may provide a more comprehensive picture of liver health and disease processes.
Liver Function Tests in Special Populations
Interpreting liver function tests can be particularly challenging in certain patient populations. Healthcare providers must consider various factors that can influence test results and their interpretation in these groups:
Pediatric Patients
Liver enzyme levels in children can differ from adult reference ranges due to ongoing growth and development. Key considerations include:
- Age-specific reference ranges for liver enzymes
- Higher AP levels during periods of rapid bone growth
- Potential for congenital liver disorders or metabolic diseases
Pregnant Women
Pregnancy-induced changes can affect liver function test results. Important factors to consider include:
- Physiological increase in AP due to placental production
- Slight elevations in ALT and AST in late pregnancy
- Risk of pregnancy-specific liver disorders (e.g., intrahepatic cholestasis of pregnancy, HELLP syndrome)
Elderly Patients
Aging can impact liver function and the interpretation of liver tests. Considerations include:
- Reduced liver mass and blood flow with age
- Increased susceptibility to drug-induced liver injury
- Higher prevalence of comorbidities that can affect liver function
Patients with Chronic Diseases
Certain chronic conditions can influence liver function test results, even in the absence of primary liver disease. Examples include:
- Diabetes: Can cause fatty liver and elevated liver enzymes
- Heart failure: May lead to congestive hepatopathy
- Thyroid disorders: Can affect liver enzyme levels
How can healthcare providers ensure accurate interpretation of liver function tests in these special populations? A comprehensive approach is essential, including:
- Using age- and population-specific reference ranges when available
- Considering physiological changes associated with specific conditions (e.g., pregnancy)
- Evaluating liver function tests in the context of the patient’s overall health status and medical history
- Conducting additional targeted testing when necessary to clarify ambiguous results
By taking these factors into account, healthcare providers can more accurately assess liver health and make informed decisions about further evaluation and management in diverse patient populations.
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.
1
and , M.D.
1
,
2
,
3
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Abbreviations
- AIH
- autoimmune hepatitis
- ALT
- alanine aminotransferase
- AMA
- antimitochondrial antibodies
- AP
- alkaline phosphatase
- AST
- aspartate aminotransferase
- DILI
- drug‐induced liver injury
- ERCP
- endoscopic retrograde cholangiopancreatography
- gGT
- γ‐glutamyl transpeptidase; LIT, liver injury test
- MELD
- Model for End‐Stage Liver Disease
- MRCP
- magnetic resonance cholangiopancreatography
- NASH
- nonalcoholic steatohepatitis
- PBC
- primary biliary cholangitis
- ULN
- 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
Parameter | Origin | Associated Disease |
---|---|---|
AST | Liver, skeletal muscle, cardiac muscle, red blood cells, brain, pancreas, lungs | Hepatocellular injury of any cause, myopathies, myocardial infarct, hemolysis |
ALT | Liver, kidneys, skeletal muscle | Hepatocellular injury of any cause, myopathies |
AP | Liver, bone, placenta, kidneys, intestines | Cholestatic liver disease; sarcoidosis; pregnancy; lymphoma; bone, kidney, and intestinal diseases |
γ‐Glutamyl transferase | Biliary epithelial cells, kidneys, pancreas, prostate | Biliary or pancreatic disease, myocardial infarct, renal diseases, chronic lung disease, diabetes |
Conjugated bilirubin | Hemolysis, insufficient excretion from the liver | Severe liver injury from any cause Rotor syndrome, Dubin‐Johnson syndrome |
Unconjugated bilirubin | Hemolysis | Hemolysis, Gilbert syndrome, Crigler‐Najjar syndrome |
Albumin | Produced in hepatocytes | Low in nephrotic syndrome, malnutrition, protein‐losing enteropathy |
Prothrombin time | Clotting factors produced in hepatocytes | Prolonged in liver disease, vitamin K deficiency, fat malabsorption, pancreatic insufficiency |
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Table 2
Elevation of Liver Chemistries With Liver Diseases
Test | Hepatocellular | Cholestatic | Half‐life (t 1/2) |
---|---|---|---|
AST | +++ | N/+ | 17 hours |
ALT | +++ | N/+ | 47 hours |
AP | Normal/mild | ++++ | 7 days |
gGT | ++/+++ | ++++ | 26 days (for abstinence) |
Total bilirubin | N/++ | N/+++ | Depends on albumin binding |
Albumin | ++ (chronic) | N | 20 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 Predominant | ALT Predominant |
---|---|
Alcohol‐related liver injury | Chronic hepatitis C |
Cirrhosis | Chronic hepatitis B |
Hemolysis | Acute viral hepatitis (types A‐E, herpes simplex virus, Epstein‐Barr virus, cytomegalovirus) |
Myopathy | Steatosis/steatohepatitis |
Thyroid disease | Hemochromatosis |
Strenuous exercise | Medications/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
Hepatic | Nonhepatic |
---|---|
Bile duct obstruction | Bone disease |
Benign intrahepatic recurrent cholestasis | Pregnancy |
Primary biliary cholangitis | Chronic renal failure |
Primary sclerosing cholangitis | Lymphoma and other malignancies |
Medications | Congestive heart failure |
Infiltrating diseases of the liver | Childhood growth |
Sarcoidosis | |
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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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
Antibiotics
- 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.
Bay Biosciences is a global leader in providing researchers with high quality, clinical grade, fully characterized human tissue samples, bio-specimens and human bio-fluid collections.
Samples available are cancer (tumor) tissue, cancer serum, cancer plasma cancer PBMC and human tissue samples from most other therapeutic areas and diseases.
Bay Biosciences maintains and manages its own bio-repository, human tissue bank (biobank) consisting of thousands of diseased samples (specimens) and from normal healthy donors available in all formats and types.
Our biobank procures and stores fully consented, deidentified and institutional review boards (IRB) approved human tissue samples and matched controls.
All our human tissue collections, human specimens and human bio-fluids are provided with detailed samples associated patient’s clinical data.
This critical patient’s clinical data includes information relating to their past and current disease, treatment history, lifestyle choices, biomarkers and genetic information.
Patient’s data is extremely valuable for researchers and is used to help identify new effective treatments (drug discovery & development) in oncology, other therapeutic areas and diseases.
Bay Biosciences banks wide variety of human tissue samples and biological samples including cryogenically preserved at – 80°C.
Including fresh frozen tissue samples, tumor tissue samples, FFPE’s, tissue slides, with matching human bio-fluids, whole blood and blood derived products such as serum, plasma and PBMC’s.
Bay Biosciences is a global leader in collecting and providing human tissue samples according to the researchers specified requirements and customized, tailor-made collection protocols.
Please contact us anytime to discuss your special research projects and customized human tissue sample requirements.
Bay Biosciences provides human tissue samples (human specimens) from diseased and normal healthy donors which includes:
- Peripheral whole-blood,
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- Serum (sera)
- Plasma
- Peripheral blood mononuclear cells (PBMC’s)
- Saliva
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- Urine
- Stool samples
- Aqueous humor
- Vitreous humor
- Kidney stones (renal calculi)
- Other bodily fluids from most diseases including cancer.
We can also procure most human bio-specimens and can-do special collections and requests of human samples that are difficult to find. All our human tissue samples are procured through IRB approved clinical protocols and procedures.
In addition to the standard processing protocols Bay Biosciences can also provide human plasma, serum, PBMC bio-fluid samples using custom processing protocols, you can buy donor specific sample collections in higher volumes and specified sample aliquots from us.
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Basic biochemical parameters
Comprehensive laboratory examination, including all the main biochemical blood parameters and allowing to evaluate the function of the liver (ALT, AST, total bilirubin), kidney function (urea, creatinine), as well as the metabolism of carbohydrates (glucose), lipids (total cholesterol) and proteins (total protein).
Synonyms Russian
Main biochemical parameters of blood.
Synonyms English
Biochemical profile, Basic biochemical blood tests.
What biomaterial can be used for research?
Venous blood.
How to properly prepare for an examination?
- Do not eat for 12 hours before the test, you can drink pure non-carbonated water.
- Exclude physical and emotional overexertion within 30 minutes prior to the study.
- Do not smoke for 30 minutes before the test.
General information about the study
Basic biochemical parameters of blood allow for a comprehensive assessment of the functions of various organs and systems. Together with a general blood test (CBC) and a general urinalysis (OAM), this comprehensive study is included in the “clinical minimum” of tests, which is performed almost every time a patient visits a doctor. The analysis is screening and includes baseline indicators that can be used to assess the main functions of the human body and suspect the most common diseases.
1. To assess liver function, the liver enzymes alanine aminotransferase (ALT) and aspartate aminotransferase (ALT) and total bilirubin are examined.
ALT and AST are enzymes that catalyze the transfer of amino groups between amino acids (transaminases). Although these enzymes can also be found in many other tissues and organs (heart, skeletal muscle, kidneys, brain, red blood cells), changes in their concentration in the blood are more often associated with liver disease, which leads to their name – hepatic transaminases. ALT is a more specific marker of liver disease than AST. With viral hepatitis and toxic liver damage, as a rule, the same increase in the level of ALT and AST is observed. In alcoholic hepatitis, liver metastases, and liver cirrhosis, there is a more pronounced increase in AST than ALT. It should be noted that there is no direct relationship between the degree of liver damage and the level of hepatic transaminases.
Bilirubin is a pigment formed during the breakdown of hemoglobin and some other heme-containing proteins in the liver, spleen and bone marrow. Total bilirubin is a combination of unbound (indirect, associated with albumin) and associated with glucuronic acid (direct) bilirubin. An increase in the level of bilirubin can be observed in many liver diseases, however, the greatest value of this marker lies in the differential diagnosis of jaundice and the diagnosis of biliary tract obstruction. With an increase in the level of total bilirubin, it is advisable to conduct a study of direct bilirubin and calculate the value of indirect bilirubin, as well as to study the concentrations of such markers of biliary tract obstruction as alkaline phosphatase (AP) and gamma-glutamyl transpeptidase (GGTP).
2. Serum creatinine and urea are measured to evaluate kidney function.
Creatinine is the end product of the metabolism of creatine phosphate, an energy substrate produced in the muscles. Creatinine is freely filtered by the glomeruli and is used as an indicator of glomerular filtration rate (GFR) and overall kidney function. Elevated serum creatinine is indicative of reduced GFR and impaired renal function, but can also be seen with dehydration and muscle damage. It should be noted that a change in the level of creatinine is not an early sign of kidney disease: an increase in its level above the upper limit of the norm is observed with a decrease in GFR by as much as 50%. This is especially important when examining elderly patients in whom a progressive decrease in GFR is not accompanied by a deviation in the level of creatinine from the norm due to a decrease in its production in the body of an elderly person. For this reason, serum creatinine is not recommended as the sole measure of renal function. GFR is considered to be the best indicator of kidney function, which can be obtained either from a calculation using serum creatinine concentration (as well as sex, age, race and body size) or using Rehberg’s test.
Urea is an end product of protein metabolism, formed in the liver and excreted by the kidneys. This indicator is traditionally used together with creatinine to assess kidney function, but can also indicate liver disease.
3. Glucose is an integral indicator of carbohydrate metabolism and one of the criteria for diagnosing diabetes mellitus (DM). Regular measurement of fasting blood glucose levels will allow diagnosing diabetes in time and preventing its complications.
4. Total cholesterol – an integral indicator of lipid metabolism and one of the criteria for diagnosing atherogenic dyslipidemias. Regular measurement of cholesterol levels will make it possible to diagnose lipid metabolism disorders in time and prevent such diseases of the cardiovascular system as myocardial infarction. Currently, it is recommended to start measuring the level of total cholesterol at the age of 35 years in men and 45 years in women, or earlier in the presence of several risk factors for cardiovascular diseases (for example, a history of familial hypercholesterolemia aggravated, the presence of a relative with early coronary artery disease). It should be noted that the most accurate information about lipid metabolism will be obtained by performing a lipidogram, which includes, in addition to total cholesterol, other indicators, including the main fractions of blood lipoproteins.
5. Total protein – an integral indicator of protein metabolism. Of greater importance is a decrease in total protein, which can be observed in malnutrition (anorexia, starvation), the presence of chronic infectious (tuberculosis), inflammatory (rheumatoid arthritis) and oncological diseases, as well as impaired liver function (cirrhosis of the liver), kidneys (nephrotic syndrome) and intestinal absorption function (protein-losing enteropathy).
This comprehensive analysis includes basic biochemical parameters and allows you to suspect underlying diseases. Additional laboratory tests may be required for more accurate health information.
It should be noted that the deviation of any indicator from the norm does not always indicate the presence of a disease, and the result of the analysis should be interpreted in conjunction with all available data about the patient.
The most accurate information about the patient’s health status will be obtained by assessing baseline indicators in dynamics, that is, by comparing repeated analyzes. Repeated analyzes are recommended to be performed using the same test systems, that is, in the same laboratory.
What is the study used for?
- For a comprehensive assessment of the patient’s health status;
- for the timely detection of major diseases.
When is the examination scheduled?
- At annual patient examination;
- when a patient seeks medical care.
What do the results mean?
Reference values
For each indicator included in the complex:
- [06-003] Alanine aminotransferase (ALT)
- [06-010] Aspartate aminotransferase (AST)
- [06-015] Plasma glucose
- [06-021] Serum creatinine (with GFR determination)
- [06-034] Serum urea
- [06-035] Total whey protein
- [06-036] Bilirubin total
- [06-048] Cholesterol, total
Important notes
- The results of the study are evaluated taking into account additional clinical, instrumental and laboratory data.
Also recommended
[40-039] Lipidogram
[02-011] Rehberg’s test (endogenous creatinine clearance)
Who prescribes tests?
Therapist, general practitioner.
Literature
- Johnson CA, Levey AS, Coresh J, Levin A, Lau J, Eknoyan G. Clinical practice guidelines for chronic kidney disease in adults: Part II. Glomerular filtration rate, proteinuria, and other markers. Am Fam Physician. 2004 Sep 15;70(6):1091-7.
- McPhee S.J., Papadakis M. CURRENT Medical Diagnosis and Treatment / S. J. McPhee, M. Papadakis; 49 ed. – McGraw-Hill Medical, 2009.
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.
Analyzes
Total bilirubin
1 day
from 125 ₽
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from 125 ₽
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Alanine aminotransferase (ALT)
1 day
from 125 ₽
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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 INTRODUCTORY 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.
Myoglobin
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
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
Procalcitonin rises in the blood during bacterial infections, sepsis, septic shock, multiple organ failure, and some other serious conditions.
Electrolytes
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
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.
Cholesterol
- 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.
Pigments
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. Normally – 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.
Iron
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.
Enzymes
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.