Lactate Dehydrogenase (LD) (LDH) Most Popular

The Lactate Dehydrogenase (LD) (LDH) test contains 1 test with 1 biomarker.

Brief Description: The Lactate Dehydrogenase (LDH) test is a laboratory test that measures the levels of LDH enzyme in the blood. LDH is an enzyme found in almost all body tissues, including the heart, liver, muscles, kidneys, and red blood cells. The LDH test provides information about tissue damage or disease processes occurring in various organs.

Also Known As: LD Test, LDH Test, Lactic Acid Dehydrogenase Test

Collection Method: Blood Draw

Specimen Type: Serum

Test Preparation: No preparation required

When is a Lactate Dehydrogenase test ordered?

A Lactate Dehydrogenase test may be ordered in various situations:

1. Assessment of Tissue Damage: It is commonly ordered to evaluate tissue damage or injury. LDH levels can rise in response to cell damage or death, indicating potential organ involvement.

2. Diagnosis and Monitoring of Diseases: The LDH test may be used to assist in the diagnosis and monitoring of various diseases, including liver disease, heart attack, certain cancers, and hemolytic anemia.

3. Monitoring Treatment Response: LDH levels can be monitored over time to assess the response to treatment or to determine the progression of a disease.

What does a Lactate Dehydrogenase blood test check for?

Lactate dehydrogenase is an energy-producing enzyme found in nearly all of the body's cells, with the highest concentrations in the heart, liver, muscles, kidneys, lungs, and blood cells; bacteria also produce LD. This test determines the amount of LD in the blood or other bodily fluids.

In the fluid component of the blood, just a little quantity of LD is normally measurable. When cells are injured or destroyed, LD is released into the bloodstream. As a result, an LD blood level is a non-specific indicator of tissue damage elsewhere in the body. It cannot be used to determine the underlying cause or location of cellular damage on its own. It can, however, be used in conjunction with other blood tests to assist diagnose and/or monitor disorders that cause tissue damage, such as liver or blood diseases, or cancer.

Fluid can accumulate or the components of the fluid present can change when there is damage, inflammation, or infection in a specific area of the body, such as the brain, heart, or lungs. The amount of LD in the fluid could help you figure out what's wrong. When a person has bacterial meningitis, for example, LD levels in the cerebrospinal fluid are usually high. The LD test, in combination with other tests, can be used to detect whether fluid buildup around the heart, lungs, or abdominal cavity is caused by injury or inflammation or by an imbalance of fluid pressure inside blood vessels and blood protein levels. Some fluids that can be analyzed using an LD test are listed in the article on Body Fluid Analysis.

Lab tests often ordered with a Lactate Dehydrogenase test:

When an LDH test is ordered, several other tests are often conducted alongside to help pinpoint the source of tissue damage or to diagnose specific conditions. Here are some common tests ordered with an LDH test:

1. Complete Blood Count (CBC):

   • Purpose: To provide a broad picture of overall blood health, including red and white blood cells and platelets.
   • Why Is It Ordered: A CBC can help determine if there’s evidence of hemolysis (breakdown of red blood cells), which can elevate LDH levels, or to detect other blood disorders.

2. Liver Function Test:

   • Purpose: To assess liver health, as LDH levels can rise with liver damage.
   • Why Is It Ordered: Tests like alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), and bilirubin can help determine if liver disease is the cause of increased LDH.

3. Kidney Function Test:

   • Purpose: To evaluate kidney function.
   • Why Is It Ordered: Kidney disease can affect LDH levels, so these tests can be useful in assessing kidney involvement.

4. Electrolyte Panel:

   • Purpose: To measure electrolyte levels like sodium, potassium, chloride, and bicarbonate.
   • Why Is It Ordered: Electrolyte imbalances can accompany or contribute to conditions that also elevate LDH.

5. Bilirubin Test:

   • Purpose: To measure the level of bilirubin in the blood, which can rise in liver disease and hemolysis.
   • Why Is It Ordered: To further assess liver function and to check for hemolysis.

6. Haptoglobin:

   • Purpose: Haptoglobin binds free hemoglobin released during hemolysis.
   • Why Is It Ordered: Low levels of haptoglobin can confirm hemolysis, which may be associated with increased LDH.

7. Uric Acid:

   • Purpose: To measure the level of uric acid in the blood, which can be a byproduct of cell turnover.
   • Why Is It Ordered: Elevated uric acid levels can be associated with conditions like leukemia or lymphoma, where rapid cell turnover (which also increases LDH) occurs.

These tests, when ordered alongside an LDH test, provide a comprehensive evaluation of potential sources of cell or tissue damage and contribute to a more accurate diagnosis of the underlying condition. The specific combination of tests will depend on the individual’s symptoms, medical history, and the clinical context in which the elevated LDH was found.

Conditions where a Lactate Dehydrogenase test is recommended:

A Lactate Dehydrogenase test is useful in the evaluation and management of various conditions, including:

1. Liver Disease: LDH levels may be elevated in liver diseases such as hepatitis, cirrhosis, or liver cancer, indicating liver cell damage.

2. Heart Attack: LDH levels can be elevated after a heart attack due to damage to heart muscle cells.

3. Hemolytic Anemia: Hemolytic anemia, a condition characterized by the destruction of red blood cells, can cause an increase in LDH levels.

4. Certain Cancers: LDH levels may be elevated in certain cancers, such as lymphoma, leukemia, or metastatic cancers, reflecting increased cell turnover or tissue damage.

How does my healthcare provider use a Lactate Dehydrogenase test?

Healthcare providers use the results of a Lactate Dehydrogenase test to:

1. Assess Tissue Damage: Increased LDH levels can indicate tissue damage or injury, helping healthcare providers identify the affected organs and guide further evaluation or treatment.

2. Diagnose and Monitor Diseases: LDH levels, in combination with other clinical and diagnostic findings, assist in the diagnosis and monitoring of various diseases, including liver disease, heart attack, certain cancers, and hemolytic anemia.

3. Monitor Treatment Response: LDH levels can be monitored over time to assess the response to treatment or to determine disease progression. A decrease in LDH levels may indicate a positive response to therapy, while persistently high levels may require further investigation or treatment modifications.

It is important to note that the interpretation and utilization of Lactate Dehydrogenase test results should be done by a qualified healthcare provider who considers the patient's medical history, symptoms, and other relevant factors. Treatment decisions are individualized based on the specific clinical context.

What do my lactate dehydrogenase test results mean?

LD values that are elevated usually indicate tissue damage. As cellular death begins, LD levels normally climb, peak after a period of time, and then begin to diminish. LD levels are raised in a number of situations, indicating that it has a wide tissue distribution.

Elevated LD levels may be seen with:

• Hemolytic anemia
• Pernicious anemia 
• Infectious mononucleosis
• Meningitis
• Encephalitis
• HIV
• Sepsis
• Intestinal and pulmonary infarctions
• Acute kidney disease
• Acute hepatitis
• Acute muscle damage
• Pancreatitis
• Fractures of the bones
• Malignancies of the testicles, lymphoma, or other cancers

A high level of LD in the blood may suggest that cancer treatment has failed. A high level is associated with a poorer prognosis for cancer patients. Moderately high LD blood levels may remain in several chronic and progressive diseases. LD levels that are low or normal do not usually indicate a concern. When a high amount of ascorbic acid is consumed, low levels can occur.

Fluids in the body:

• Cerebrospinal fluid—a high LD implies bacterial meningitis, whereas a low or normal amount indicates viral meningitis is more likely.
• Pericardial fluid, peritoneal fluid, or pleural fluid with a high LD is an exudate, while fluid with a low LD is a transudate. Cirrhosis or congestive heart failure are the most common causes of transudates. Exudates can have a variety of causes, and determining the cause usually necessitates additional testing.

Most Common Questions About the Lactate Dehydrogenase test:

Understanding the Test

What is the Lactate Dehydrogenase test?

The Lactate Dehydrogenase test, often abbreviated as LDH test, is a blood test that measures the levels of lactate dehydrogenase, an enzyme found in many body tissues such as the heart, liver, kidneys, skeletal muscles, brain, blood cells, and lungs.

Why would someone need a Lactate Dehydrogenase test?

The Lactate Dehydrogenase test is often used when a healthcare provider suspects tissue damage or disease, as LDH levels can be elevated when there's damage to cells where the enzyme is found. Conditions like heart attack, liver disease, anemia, muscular dystrophy, and others can cause high LDH levels.

Interpreting the Results

What do the results of the Lactate Dehydrogenase test mean?

LDH levels are measured in units per liter (U/L). Normal LDH levels usually range from 140 U/L to 280 U/L, but this can vary slightly depending on the laboratory. Higher levels of LDH can suggest cell damage or disease, while lower levels are usually not concerning.

How are the results of the Lactate Dehydrogenase test presented?

Results are usually presented as a numerical value in units per liter (U/L). This represents the concentration of LDH in the bloodstream.

About the Test

What factors can affect the results of the Lactate Dehydrogenase test?

Several factors can affect LDH levels, including alcohol consumption, vigorous exercise, use of certain medications, and other health conditions like viral or bacterial infections.

Understanding the Implications

What conditions can cause abnormal Lactate Dehydrogenase levels?

Conditions that can cause elevated LDH levels include heart disease, liver disease, lung disease, anemia, muscle dystrophy, and cancers. High levels can also be due to physical trauma or injury, which causes cell damage and release of LDH.

What are the implications of abnormal Lactate Dehydrogenase levels?

Abnormally high LDH levels may indicate damage or disease in organs that contain the enzyme. It's important to note that LDH test results are often used in conjunction with other tests to make a definitive diagnosis.

Risks and Precautions

How do abnormal Lactate Dehydrogenase levels impact health?

Abnormal LDH levels may indicate a serious underlying condition such as heart disease, liver disease, or cancer. If left untreated, these conditions can lead to serious health complications.

Dealing with Abnormal Results

What steps should be taken if the Lactate Dehydrogenase test results are abnormal?

If your LDH levels are abnormally high, your healthcare provider may order additional tests to identify the underlying cause. Depending on the results, treatment may include medication, lifestyle changes, or other therapies.

Interpreting the Test Results

What is the significance of elevated Lactate Dehydrogenase levels in the blood?

Elevated LDH levels in the blood can indicate cell damage or death, as the enzyme is released into the bloodstream when cells are destroyed. This can be due to various conditions, including heart disease, liver disease, and certain types of cancer.

Understanding the Importance of the Test

How does the Lactate Dehydrogenase test assist in diagnosing disease?

The Lactate Dehydrogenase test can be used as part of a diagnostic process when disease is suspected. Elevated LDH levels can indicate tissue damage or disease. However, since LDH is found in many parts of the body, it cannot specify the location of the damage or disease, and other tests are often needed to confirm a diagnosis.

Discussion with Healthcare Provider

What questions should I ask my healthcare provider before getting the Lactate Dehydrogenase test?

You might ask: "Why do you recommend this test for me?", "What could cause elevated LDH levels?", or "What will we do if my LDH levels are abnormal?".

What do I discuss with my healthcare provider after receiving the Lactate Dehydrogenase test results?

You might discuss the meaning of your results, potential causes of abnormal LDH levels, any recommended treatments or follow-up tests, and steps you can take to manage your health.

Relationship with Other Tests

How does the Lactate Dehydrogenase test relate to other enzyme tests?

The Lactate Dehydrogenase test is one of many enzyme tests that can be used to assess tissue damage or disease. Other related tests include the aspartate aminotransferase (AST) and alanine aminotransferase (ALT) tests, which assess liver function, and the creatine kinase (CK) test, which can indicate muscle damage. These tests are often used together to provide a more comprehensive view of a patient's health.

How does the Lactate Dehydrogenase test complement other diagnostic tools?

The LDH test often complements other diagnostic tools because it can indicate tissue damage or disease, but it cannot specify the location or cause. Other tests and assessments may be needed to make a diagnosis, but the LDH test can provide a helpful clue that something is wrong.

The Test and Specific Conditions

Can the Lactate Dehydrogenase test help diagnose liver disease?

Yes, the Lactate Dehydrogenase test can help in the diagnosis of liver disease. Elevated LDH levels can be a sign of liver damage or disease, but other tests are usually needed to confirm the diagnosis.

Can the Lactate Dehydrogenase test help detect heart disease?

Yes, the LDH test can help detect heart disease. In particular, it may be used to assess whether a patient has had a heart attack, as LDH levels can rise significantly within 24 hours of a heart attack and remain elevated for several days.

About the Enzyme

What role does Lactate Dehydrogenase play in the body?

Lactate Dehydrogenase is an enzyme that helps convert sugar into energy in the body's cells. It is found in many tissues throughout the body and is essential for cellular function and energy production.

Why is Lactate Dehydrogenase present in so many tissues?

Because it plays a crucial role in energy production, Lactate Dehydrogenase is needed in all cells of the body. It's especially abundant in tissues and organs that have high energy requirements, such as the heart, liver, and muscles.

Future Implications

What future medical tests might be needed if the Lactate Dehydrogenase test reveals abnormal results?

If the LDH test reveals abnormal results, further diagnostic tests may be needed to identify the cause. This could include other enzyme tests, imaging tests, or tissue biopsies, depending on the suspected condition.

Can the Lactate Dehydrogenase test provide insights into overall health?

While the LDH test isn't a comprehensive measure of overall health, it can provide important insights into tissue health and cellular function. It's often one piece of the puzzle in a larger diagnostic process.

Can the Lactate Dehydrogenase test contribute to preventative healthcare?

By helping to detect tissue damage or disease early on, the LDH test can certainly contribute to preventative healthcare. Early detection can lead to early treatment, which can prevent more serious health complications down the line.

Special Populations

How does the Lactate Dehydrogenase test relate to cancer patients?

In cancer patients, the LDH test is often used to monitor disease progression or response to treatment. Some cancers cause elevated LDH levels, and these levels can decrease if treatment is working.

Why might athletes require a Lactate Dehydrogenase test?

Athletes may require an LDH test if there's a suspicion of muscle damage or disease, as intense exercise can cause a temporary rise in LDH levels. However, persistently high levels may indicate a more serious issue.

Can the Lactate Dehydrogenase test be used in the management of infectious diseases?

Yes, the LDH test can be useful in managing infectious diseases. Some infections can cause cell damage or death, leading to elevated LDH levels. Monitoring these levels can help healthcare providers assess the severity of the infection and the body's response to treatment.

We advise having your results reviewed by a licensed medical healthcare professional for proper interpretation of your results.