Lactate dehydrogenase is an enzyme which can be found in many tissues within the human body. It is found in higher levels in the liver, kidneys, heart, muscles, blood, brain, and lungs. It can also be found in some of the bacteria which may cause disease. When cells are damaged, then they will release this enzyme and the LDH blood test can then detect them. If it is found in specific locations, such as the cerebrospinal fluid, then this may indicate the presence of a specific disease.
The LDH blood test is most commonly used to discover and learn the extent of acute or chronic tissue damage. It may also be ordered to monitor or detect a progressive condition, a severe infection, or to help stage cancers.
LDH blood tests may also be ordered in combination with other lactate dehydrogenase tests on other body fluids to guide treatment options for a patient. It can also be used to evaluate whether suspected meningitis is bacterial or viral in nature.
When Is the LDH Blood Test Ordered?
Some patients may have the LDH blood test ordered as part of their annual physical exam, in combination with the CMP blood test. This is most commonly done if there is a suspicion of inflammation occurring based on the interview portion of the exam or findings made by the doctor.
Medical providers will also order the LDH blood test when a suspected muscle trauma or other injury occurs and a patient is suffering from the signs and symptoms of hemolytic anemia. It may also be ordered with body fluid tests if there is a suspected buildup of fluids around the heart and lungs or if meningitis is suspected.
Patients diagnosed with cancer may also receive this blood test on a frequent basis to help monitor their health and to make treatment plan changes as necessary.
What Do My LDH Blood Test Results Mean?
If the LDH blood tests come back as being negative or “normal,” then this indicates that there isn’t an increased level of lactase dehydrogenase. This means a patient’s bothersome signs and symptoms are being caused by a different issue than tissue inflammation, damage, or destruction. Some patients may have a “low” test result – this generally happens with people who consume high levels of vitamin C on a regular basis.
If the LDH blood tests come back as being “positive” or “abnormal,” then this generally indicated that some type of tissue damage is occurring. Lactase dehydrogenase levels usually rise when cellular destruction begins to occur. It will then peak after some time, then slowly begin to fall.
There may be a number of health concerns that are associated with a positive LDH blood test result. Based on combination of a patient’s signs and symptoms and the test results, the results may indicate a simple bone fracture, an acute muscle injury, or acute kidney or liver disease. Certain cancers, viral infections [such as HIV], and pancreatitis also typically show higher levels of lactase dehydrogenase.
For patients who are receiving treatments for their health condition, a high LDH result may also indicate that the treatment plan is ineffective. In chronic or progressive diseases, LDH levels may be persistently higher even with an effective treatment plan in place.
Here’s What You Need to Know About the LDH Blood Test
Although the positive LDH blood test results may lead to concerning health conditions, there are many lifestyle choices that can cause a positive result without the associated concerns. A strenuous workout, for example, can cause someone to experience a temporary increase in LDH levels. It will also occur when hemolysis occurs within the blood collected for testing, especially if it is stored improperly or was difficult to collect.
Some people have naturally high platelet counts in their blood. When this occurs, their LDH levels may also be naturally higher even when there are no health concerns of note.
In the past, the LDH blood test was used to diagnose and/or monitor heart attacks, but this blood test is evolving into a go-to test for any possible tissue damage. It’s not tissue specific, so the only thing it can tell a medical provider is that damage has occurred or is continuing to do so. This is why other tests are often ordered in combination with the LDH blood test.
If you have health concerns that may be resolved by the LDH blood test or you have additional questions about your results, make sure to speak with your treating doctor so an effective treatment plan may be developed. This way you can make sure that you’re taking charge of your health.