What is the normal enzyme level for the liver. Normal Liver Enzyme Levels: Understanding High, Low & Normal Results, Symptoms & Causes

02.09.202316.06.2023 by alexxlab

What are the normal ranges for liver enzyme levels. How do high or low liver enzyme levels affect your health. What causes abnormal liver enzyme levels and what symptoms should you watch for. Learn about the importance of liver enzyme tests in diagnosing various health conditions.

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Understanding Liver Enzymes and Their Function

Liver enzymes play a crucial role in maintaining our overall health. These specialized proteins facilitate various chemical reactions within the liver, aiding in essential functions such as metabolizing nutrients, filtering toxins, and producing vital proteins. By measuring liver enzyme levels in the blood, healthcare professionals can gain valuable insights into the liver’s health and function.

The two primary liver enzymes commonly tested are:

Alanine aminotransferase (ALT)
Aspartate aminotransferase (AST)

While ALT is primarily produced by the liver, AST can originate from various organs, including the liver, heart, muscles, kidneys, and brain. Understanding the normal ranges and potential causes of abnormal levels is essential for maintaining optimal liver health.

Normal Liver Enzyme Levels: What You Need to Know

Knowing the normal ranges for liver enzyme levels is crucial for interpreting test results accurately. However, it’s important to note that these ranges can vary slightly between laboratories and may be influenced by factors such as age, gender, and race.

For ALT, the generally accepted normal ranges are:

Men: 29-33 IU/L (International Units per Liter)
Women: 19-25 IU/L

For AST, the normal ranges typically fall within:

Men: 10-40 IU/L
Women: 9-32 IU/L

When interpreting your liver enzyme test results, always refer to the specific reference ranges provided by the laboratory conducting the test, as these can vary between facilities.

High Liver Enzyme Levels: Causes and Implications

Elevated liver enzyme levels often indicate inflammation or damage to liver cells. This increase can be attributed to various factors, ranging from acute injuries to chronic conditions. Some common causes of high liver enzyme levels include:

Medications (prescription and over-the-counter)
Alcohol consumption
Liver diseases (hepatitis, fatty liver disease, cirrhosis)
Obesity
Viral infections
Heart conditions
Autoimmune disorders
Metabolic disorders

Is it possible for liver enzyme levels to be temporarily elevated? Yes, certain activities or short-term conditions can cause a transient increase in liver enzyme levels. These may include strenuous exercise, recent surgeries, or acute infections. In such cases, the levels typically return to normal once the underlying cause is resolved.

Low Liver Enzyme Levels: Should You Be Concerned?

While high liver enzyme levels often receive more attention, low levels can also indicate potential health issues. Low liver enzyme levels may be associated with:

Vitamin B6 deficiency
Chronic kidney disease
Certain medications
Frailty in older adults

Are low liver enzyme levels always a cause for concern? Not necessarily. In some cases, lower-than-average enzyme levels may simply reflect individual variations or a highly efficient liver. However, persistently low levels should be discussed with a healthcare provider to rule out underlying conditions.

Symptoms Associated with Abnormal Liver Enzyme Levels

Abnormal liver enzyme levels don’t always produce noticeable symptoms, especially in the early stages. However, as liver function becomes more compromised, various signs may emerge. Some common symptoms associated with liver problems include:

Fatigue and weakness
Jaundice (yellowing of skin and eyes)
Abdominal pain or swelling
Nausea and loss of appetite
Dark urine
Pale stools
Itchy skin
Easy bruising or bleeding

Can abnormal liver enzyme levels cause weight changes? Yes, both weight loss and weight gain can be associated with liver problems. Unexplained weight loss may occur due to decreased appetite and impaired nutrient absorption, while weight gain might result from fluid retention in advanced liver disease.

The Importance of Liver Enzyme Tests in Diagnosis

Liver enzyme tests play a crucial role in diagnosing various health conditions. These tests can help healthcare providers:

Detect liver damage or disease
Monitor the progression of liver conditions
Evaluate the effectiveness of treatments
Assess overall liver function
Screen for potential side effects of medications

How often should liver enzyme tests be performed? The frequency of liver enzyme tests depends on individual health factors and risk profiles. For healthy individuals, these tests may be part of routine annual check-ups. However, people with known liver conditions or those taking medications that can affect liver function may require more frequent monitoring.

Lifestyle Factors Affecting Liver Enzyme Levels

Various lifestyle factors can influence liver enzyme levels. Being aware of these factors can help individuals maintain optimal liver health:

Diet: A balanced diet rich in fruits, vegetables, and whole grains supports liver health.
Exercise: Regular physical activity can help maintain a healthy weight and reduce the risk of fatty liver disease.
Alcohol consumption: Excessive alcohol intake can lead to liver damage and elevated enzyme levels.
Hydration: Adequate water intake supports overall liver function.
Sleep: Proper sleep patterns contribute to liver health and overall well-being.
Stress management: Chronic stress can negatively impact liver function.

Can dietary supplements affect liver enzyme levels? Some dietary supplements, particularly those containing high doses of certain vitamins or herbal extracts, can impact liver enzyme levels. Always consult with a healthcare provider before starting any new supplement regimen, especially if you have existing liver concerns.

Treatment Options for Abnormal Liver Enzyme Levels

The treatment for abnormal liver enzyme levels depends on the underlying cause. Some common approaches include:

Lifestyle modifications (e.g., dietary changes, weight loss, alcohol reduction)
Medication adjustments
Treatment of underlying conditions (e.g., viral hepatitis, autoimmune disorders)
Liver-protective medications
Management of complications

Is it possible to reverse liver damage indicated by abnormal enzyme levels? In many cases, especially when caught early, liver damage can be reversed or halted through appropriate treatment and lifestyle changes. However, advanced liver disease may require more intensive interventions, including liver transplantation in severe cases.

Natural Remedies for Supporting Liver Health

While medical treatment is essential for addressing abnormal liver enzyme levels, certain natural remedies may support overall liver health:

Milk thistle: Known for its potential liver-protective properties
Turmeric: Contains curcumin, which may have anti-inflammatory effects
Green tea: Rich in antioxidants that may benefit liver function
Garlic: May help reduce fat accumulation in the liver
Leafy greens: High in chlorophyll, which may aid in liver detoxification

Can natural remedies replace medical treatment for liver problems? While natural remedies can support liver health, they should not be used as a substitute for professional medical advice and treatment. Always consult with a healthcare provider before incorporating any new supplements or natural remedies into your regimen, especially if you have existing liver concerns.

The Role of Genetics in Liver Enzyme Levels

Genetic factors can influence an individual’s liver enzyme levels and their susceptibility to certain liver conditions. Some genetic variations may affect:

Enzyme production rates
Enzyme activity levels
Susceptibility to liver diseases
Response to medications and treatments

How can genetic testing help in managing liver health? Genetic testing can provide insights into an individual’s predisposition to certain liver conditions and their potential response to treatments. This information can help healthcare providers tailor prevention strategies and treatment plans more effectively.

Liver Enzymes and Other Health Conditions

Abnormal liver enzyme levels can sometimes be indicative of health issues beyond the liver itself. Some conditions that may affect liver enzyme levels include:

Cardiovascular diseases
Diabetes
Thyroid disorders
Celiac disease
Muscular disorders
Certain cancers

Why is it important to consider non-liver conditions when evaluating liver enzyme levels? Considering the broader health context is crucial for accurate diagnosis and treatment. Elevated liver enzymes may sometimes be a secondary effect of another underlying condition, requiring a comprehensive approach to healthcare.

The Future of Liver Enzyme Testing

Advancements in medical technology are continually improving our ability to assess liver health. Some emerging trends in liver enzyme testing include:

Non-invasive imaging techniques
Biomarker discovery
Personalized medicine approaches
Artificial intelligence in result interpretation
Point-of-care testing devices

How might these advancements impact liver health management? These innovations have the potential to enhance early detection of liver problems, improve treatment monitoring, and facilitate more personalized and effective interventions for maintaining optimal liver health.

Understanding liver enzyme levels is crucial for maintaining overall health and well-being. By staying informed about normal ranges, potential causes of abnormalities, and the importance of regular monitoring, individuals can take proactive steps to support their liver health. Always consult with healthcare professionals for personalized advice and interpretation of liver enzyme test results.

Enzyme Markers: Purpose, Procedure, and Results

What are enzyme markers?

Enzymes are highly specialized complex proteins that aid chemical changes in every part of the body. For example, they help break down food so your body can use it effectively. They also help your blood clot. And they’re present in every organ and cell in your body. Enzymes are necessary for your body to function properly.

Enzyme markers are blood tests that analyze specific enzyme activity in the body. Some inherited diseases or conditions can cause these enzymes to stop working or be less efficient. Monitoring the rise or fall of enzyme levels can aid in the diagnosis of a variety of conditions.

Your doctor can order a blood test for enzyme markers, or a routine blood test to help uncover abnormalities. In some cases, you may need to take a test multiple times over the course of several days to measure changes over time.

CPK isoenzymes

The CPK isoenzymes test measures the creatine phosphokinase (CPK) in the blood. CPK enzymes are in the heart, brain, and skeletal muscles. Normal CPK levels vary by age, gender, and race.

Each laboratory may have minor differences in reference ranges, as well. In general, a CPK level of approximately 200 units per liter (U/L) or less is considered normal in an adult. This is the total CPK level in your body. More specific testing can be done, but this is not routine.

Read more: CPK isoenzymes test »

CPK-1 resides mostly in the brain and lungs. Increased levels of CPK-1 can be due to:

brain cancer
brain injury, stroke, or bleeding in the brain
pulmonary infarction, which is the death of lung tissue
seizure
electroconvulsive therapy

CPK-2 levels rise following a heart attack. Increased levels of CPK-2 may also be due to:

open heart surgery
inflammation of the heart muscle
heart injury
defibrillation
electrical injuries
chest compressions after cardiac arrest

High CPK-3 levels can be a sign of muscle stress, a crush injury, or injury due to:

muscle damage, dystrophy, or inflammation
intramuscular injections
electromyography, which is a muscle and nerve function test
recent surgery
seizures
strenuous exercise

Heart enzymes

Some heart enzymes slowly enter your blood if you’ve had a heart attack and your heart is damaged as a result. A general test for emergency room patients with heart attack symptoms is a test for the presence of certain proteins in your blood. A doctor may check CPK-2, also known as CK-MB. This marker is highly specific for heart muscle injury and rises rapidly during a heart attack. Normal CK-MB should be between 5-25 international units per liter (UI/L).

The preferred marker of heart injury, though, is a protein called troponin. Troponin should generally be less than 0.02 nanograms per milliliter (ng/mL). The level takes longer to rise than CK-MB, but the protein stays in the bloodstream longer.

Learn more: Symptoms of a heart attack »

Liver enzymes

Elevated liver enzymes may be due to inflammation or damaged liver cells. Usually, elevated liver enzymes are related to an acute injury, or a process that occurred over a short period of time due to:

prescription medications, such as statins
over-the-counter (OTC) medications, such as acetaminophen (Tylenol)
alcohol consumption
heart failure or heart attack
liver disease, such as hepatitis, fatty liver disease, cancer, and cirrhosis
obesity
celiac disease, which is a digestive condition
viruses, such as cytomegalovirus infection; hepatitis A, B, C, E viruses; mononucleosis; and Epstein-Barr virus
inflammatory diseases, such as dermatomyositis, pancreatitis, and gallbladder inflammation
muscular diseases, such as muscular dystrophy or polymyositis
ischemia, or lack of oxygen going to the liver, such as during cardiac arrest
hemochromatosis, which is a disorder in which there’s too much iron in the blood
underactive thyroid
Wilson disease, which is a disorder where there’s too much copper stored in the body
physical trauma to the organ

There are several markers that can be used to test liver function. These markers help separate whether or not the injury is to the liver parenchyma (liver cells) or to the biliary system. For the purposes of this article, the important tests are the liver aminotransferases: alanine aminotransferase (ALT) and aspartate aminotransferase (AST).

ALT is primarily produced by the liver, while AST can be from the liver, cardiac muscle, skeletal muscle, kidney, and brain. A normal ALT level is 29-33 IU/L for men, and 19-25 IU/L for women. A normal AST level may range from 10-40 IU/L for men and 9-32 IU/L for women.

These reference ranges vary from hospital to hospital. It’s important to compare your liver enzyme levels to the reference ranges provided by the lab.

The test is a routine blood test that takes place in a laboratory. No fasting or special preparation is necessary. But tell your doctor before the test about all prescription and OTC medications and supplements you take.

A blood test involves the following steps:

A healthcare provider will use an antiseptic to clean a small area of your arm, usually the inside of your elbow or the back of your hand.
They’ll then wrap an elastic band around your upper arm to create pressure and make it easier to access a vein.
They’ll insert a needle into your vein and blood will flow into a small vial. You’ll likely feel the stick of the needle or a stinging sensation.
After filling the vial, the healthcare provider will remove the elastic band and the needle.
They’ll place a bandage over the puncture site and send the blood sample to a lab for analysis.
The procedure should take only a few minutes.

Your arm may be sore at the puncture site, and you might have some mild bruising or brief throbbing.

Most people have no serious or lasting side effects from a blood test. Rare complications include:

bleeding
lightheadedness
fainting
infection, which is a small risk whenever the skin is broken

Contact your doctor immediately if you have any of these symptoms.

Abnormal test results can indicate a variety of problems from disease to a simple muscle strain because enzymes are present in every cell of your body. Your doctor will be able to determine a proper course of treatment based on your exact enzyme marker levels and the symptoms you’re having.

Are Low Values of Liver Enzymes Concerning? — Diverse Health Hub

General Health

Dec 17

Written By Christian Strohm

More Programs and Publications Featuring Dr. Kyle Riding

In this program:

Liver function tests (LFTs) include looking at ALT, ASP, and ALP enzyme levels. Watch as medical laboratory scientist Dr. Kyle Riding shares insight about what low liver enzymes can mean and cases when low levels can be medical concerns.

Transcript

Leo Hesse:

Now, Dr. Riding, with many laboratory tests, we tend to be concerned about results that are either very high or very low, and you mentioned a while ago high liver enzymes are concerning. Should we also be concerned about low values?

Dr. Kyle Riding:

That is a great question, and something that patients get very anxious over a lot is they get their lab results back for an LFT to test, and they see that their ALT or their ALP is low and they go, “Oh my goodness, should I be concerned about this?” And I’m here to reassure you that in a vast majority of clinical scenarios, low liver enzymes, so low levels of ALT, AST, or ALP are not anything to worry about, all right? Take it back to how we created reference ranges. We take a healthy group of people that we can find volunteers for us at our hospital, we draw their blood and we develop using statistical techniques, a range that covers about 95 percent of that healthy population’s results for each of those lab tests. So there’s going to be 5 percent of the population that is going to fall outside of that range that will be perfectly healthy just based on the statistical way we make the reference ranges, and biologically speaking, liver enzymes are concerning when they’re high, because that means those liver cells are rupturing and those enzymes are spilling over into the block, but when the liver enzymes are low, it could just simply mean that this patient doesn’t have a lot of liver cells turning over, meaning they’re dying and being replaced, or it simply means that their liver enzymes are just lower.

And that’s healthy for them. There’s only one major clinical scenario where low liver enzymes is a concern, and that’s in end stage liver disease or liver cirrhosis, where the liver has become so filled with scar tissue that there’s no longer really enough liver cells to produce any of those enzymes. But I will tell you, if you are in that level of liver cirrhosis, the low liver enzymes is going to be the least concerning of the laboratory results that you have, so just to kind of put the ball now, high liver enzymes are really what we’re concerned about, low liver enzymes typically are nothing to be concerned about. But if you’re ever concerned, you’re ever anxious, it’s important to always talk to your provider and find out what they could need to do in your unique situation.

The information on Diverse Health Hub is provided for educational purposes only, and is in no way intended to diagnose, cure, or treat any medical or other condition. Always seek the expert advice of your healthcare team.

glutamine transferase – GGT level in blood

The enzyme gamma-glutamine transferase (GGT) is mainly concentrated in the liver. It is also present in small amounts in some other organs. By the amount of the enzyme in the blood, one can judge the state of the liver. Normally, its concentration is low, an increase in indicators may indicate the presence of pathologies.

Indications for examination

A blood test for GGT – the level of gamma-glutamine transferase, is prescribed if there is suspicion of damage to liver cells. The causes of such damage may be different (for example: a number of diseases, poisoning with toxic substances, alcoholism, drug use). To date, this test is the most sensitive indicator of liver damage.

The analysis is prescribed if the following symptoms are present:

yellowing of the skin and sclera;
decreased appetite;
pruritus;
nausea and vomiting;
abdominal pain;
discoloration of feces and urine;
fatigue.

Also, an analysis for GGT is prescribed with a certain frequency to patients who are being treated for alcoholism. Based on its results, the doctor can judge how the patient follows his recommendations (whether the patient refused alcohol or not).

General

GGT enters the blood only if the cells are destroyed. Cell renewal is a natural process. It is he who explains the presence in the blood of a small amount of the enzyme in the absence of any pathologies. A significant increase in its concentration indicates the death of a large number of cells. The GGT assay is highly sensitive for cholestasis. If the normal outflow of bile is disturbed, the level of GGT rises before the concentration of alkaline phosphatase (AP). An increase in GGT is characteristic of many pathologies, therefore it is impossible to make an accurate diagnosis based on the results of a single analysis. This requires a comprehensive examination.

The main difference between GGT and other liver enzymes is the activation of its production under the influence of alcohol. In people who often drink alcohol, the level of the enzyme can be elevated even if there are no liver pathologies. Also, an increase in indicators in healthy people can be caused by taking a number of drugs (for example, paracetamol, antidepressants). Enzyme activity can be increased not only in case of problems with the liver, but also in pathologies of the pancreas, prostate and some other internal organs.

Research results

In most cases, the study is carried out within one day. The results are ready the next day after blood donation.

GGT norm in blood

Normally, the concentration of gamma-glutamine transferase should not exceed 55 U / l . The interpretation of the results can only be performed by the attending physician, they are not intended for self-diagnosis . This takes into account the clinical picture, anamnesis, the results of other laboratory and instrumental studies.

Increased GGT in the blood

An increase in indicators is characteristic of a number of diseases. These include viral hepatitis, cirrhosis, impaired hepatic blood flow, diabetes, malignant neoplasms, pancreatitis, and so on. In addition, an increase in the level of the enzyme can be caused by the uncontrolled intake of a number of drugs, alcohol abuse.

A GGT test is often ordered along with an alkaline phosphatase test. If the results of both tests exceed the norm, most likely the structure of the liver is damaged. In most cases, an additional examination is required to confirm the diagnosis and select an effective treatment method.

Enzymes in the human body: what are they, types and functions, enzyme tests

08.07

5152

Author: Anastasia Mokhnacheva, otorhinolaryngologist

Physicians are interested in enzymes in blood tests when they want to confirm or refute their diagnostic hypothesis. The result of the analysis is valuable only in the context: together with complaints, examination data and the results of other studies of a particular patient. We tell what the analysis shows and how the result helps the doctor to treat correctly.

What is it

The metabolism that occurs in living organisms is a set of biochemical reactions, that is, the transformation of one substance into another. Enzymes, or enzymes, are protein molecules that accelerate these transformations, they are biological catalysts. Cells of different organs and tissues have a different set of enzymes. It depends on the function that the organ performs: digestive enzymes are involved in the digestion of food, blood clotting factors are involved in stopping bleeding, mitochondrial enzymes are involved in the energy metabolism of cells.

Depending on where the enzymes work, they are isolated:

– cellular

– secretory

– excretory.

Cellular enzymes are found inside cells. They are non-specific, that is, they can be found in the cells of many organs, and specific, that is, characteristic of a particular organ. In a healthy person, the activity of cellular enzymes in the blood serum is low.

Secretory enzymes are synthesized in the liver and released into the blood, where they perform their functions, for example, blood clotting factors. Their activity in serum is high. Excretory enzymes are synthesized by the organs of the digestive system: the pancreas, the intestinal mucosa, the liver, and the cells that line the bile ducts. Normally, their activity in blood serum is low and constant.

“Currently, laboratories offer a whole range of tests for various enzymes that are involved in the reactions of internal organs. So in the diagnosis of almost all diseases, we evaluate various indicators. The most frequently and widely used are: AlAT, AsAT, amylase, creatine phosphokinase, alkaline phosphatase, lactate dehydrogenase,” comments on therapist, hematologist Lahta Clinic Maria Bushurova .

Why appoint

The study of blood serum enzymes can be carried out:

– for screening, that is, early detection of diseases, when the patient does not yet have complaints and visible symptoms

– during a diagnostic search, when, in addition to complaints, examination data, the doctor needs more objective data, to test a diagnostic hypothesis or reject it

– to monitor the disease when the diagnosis has already been established.

« Some enzymes are biomarkers for certain diseases. For example, in case of liver damage, the level of alanine and aspartate aminotransferases (AlAT, AsAT) will increase in the blood serum: they will be released from damaged hepatocytes – specialized liver cells. When the pancreas is damaged, the level of amylase and lipase increases. With muscle damage – creatine phosphokinase (CPK). – comments family doctor and therapist GMS Clinic Yuri Meshcheryakov . – However, not all enzymes are biomarkers and not all biomarkers are enzymes. For example, troponin is a marker of myocardial damage, but this protein is involved in muscle contraction, it does not catalyze biochemical reactions » .

We told in this article which markers are monitored in the blood if damage to the heart muscle is suspected. When other organs are affected, in particular the liver and pancreas, enzymes also play an important role in the diagnostic search.

For liver diseases. Alanine aminotransferase (AlAT, ALT) is a cellular enzyme of hepatocytes. The level of ALT in the blood serum of a healthy person is 4-36 U / l. Aspartate aminotransferase (AST) is also present in hepatocytes, but to a lesser extent. In healthy adults, the level of AST is 0-35 U / l. When liver cells are damaged, these enzymes enter the bloodstream, this is called cytolysis syndrome.

« Primary care physicians (general practitioners, family doctors) routinely test the level of ALT, AST as part of liver function screening, which can reveal hidden liver pathology. An increase in these enzymes may speak in favor of non-alcoholic fatty liver disease, which is not uncommon in our universe, because people eat a lot, drink a lot and move little. A less common cause is toxic and infectious liver damage, – says Yuri Meshcheryakov . — Sometimes the level of liver enzymes increases for the second time. For example, in case of heart failure, when the right parts of the heart cannot cope with a person. In these departments, pressure increases, which in a cascade provokes an increase in pressure in the venous systems, including in the veins of the liver. A “stagnation” is formed, and due to hypoxia, the cells die » .

Alkaline phosphatase is found in the cells of the liver, biliary tract, intestines, kidneys, bone tissue, placenta. The level of the enzyme in the serum of a healthy person is from 44 to 147 U / l. The level of alkaline phosphatase can increase with diseases of the hepatobiliary system, in particular when something prevents bile from flowing through the bile ducts. For example, stones in cholelithiasis or tumors of the biliary tract.

Gamma-glutamyl transpeptidase (GGTP, GTP) will be elevated in chronic alcohol abusers. Normal values for men are 8-61 U / l, for women – 5-36 U / l.

In case of pancreatic disease. Amylase is an enzyme secreted in the pancreas and salivary glands. It is a digestive enzyme that converts complex carbohydrates such as starch into smaller carbohydrates. The normal level in blood serum is from 30 to 220 U/l. With such inflammatory diseases of the glands, such as pancreatitis, parotitis, the level of amylase in the blood serum will increase, and an increase in enzyme activity will also be observed in tumor diseases of these organs.

Lipase is a digestive enzyme of the pancreas that is involved in the breakdown of fats. Normal serum values in people under 60 years of age are 10-140 U / l, over 60 years old – 24-151 U / l. An increased level of lipase is observed with pancreatitis, with kidney failure, cirrhosis, and problems with the intestines.

For evaluation of drug interactions. Enzyme levels may be tested to monitor drug side effects.

“In the practice of a primary care physician, there are situations when we are afraid of adverse drug events when prescribing certain drugs. Marker enzymes can increase with drug-induced liver damage, less often drugs can cause pancreatitis, which is more common in the practice of infectious disease doctors who manage patients with HIV infection on antiretroviral therapy. – tells Yuri Meshcheryakov . — General practitioners and general practitioners are more likely to prescribe statins, which can have a toxic effect on the liver and skeletal muscles. We will monitor the level of liver enzymes for at least three months when we prescribe this group of drugs. If the liver enzymes are not rising, then the therapy is working as it should.”

Statins are a group of drugs that are prescribed to lower blood cholesterol levels. A rare but common side effect of statins is rhabdomyolysis, when muscle cells are damaged. At the same time, the level of creatine phosphokinase will increase in serum.

Creatine phosphokinase (CPK, CK) has several forms, or isoenzymes. Isoenzymes may differ in their biochemical structure, but catalyze the same reactions. CPK-MB is an isoenzyme of the heart, it was previously monitored for suspected acute myocardial infarction, now troponin is considered a more specific marker. CPK-BB is an isoenzyme of brain tissues.