Medical knowledge, Patient Education
Lactic Dehydrogenase Test
The purpose of the lactic dehydrogenase (LDH) test is to assess for potential tissue damage caused by various conditions such as infection, blood disease, or liver disease. Additionally, LDH testing is utilized to monitor the severity of an illness or the progress of therapy.
The test specifically measures the level of LDH in the blood. LDH is an enzyme present in the blood and various tissues throughout the body, including the heart, liver, kidneys, muscles, brain, lungs, and red blood cells. LDH is composed of different parts called isoenzymes, with each isoenzyme found in different body parts as follows:
– LDH-1: Found in the heart.
– LDH-2: Found in red blood cells.
– LDH-3: Found in the lungs and other tissues.
– LDH-4: Found in the kidneys, placenta, and pancreas.
– LDH-5: Found in the liver.
To conduct the LDH test, a blood sample is taken, typically from the arm, by inserting a needle into a blood vessel.
To prepare for the test, it is advisable not to engage in strenuous exercise on the day of the test as it may affect the results. It’s also essential to follow the healthcare provider’s instructions regarding the intake of medications, as some medicines can impact the LDH test results.
The test results are reported as values, and the healthcare provider will compare them to the established normal ranges based on a large group of individuals (reference ranges). These reference ranges may vary among different laboratories and hospitals. For the LDH test, common reference ranges are as follows:
– LDH levels:
– Adult or elderly: 100–190 units/L at 37°C or 100–190 units/L (SI units).
– Child: 60–170 units/L at 30°C.
– Infant: 100–250 units/L.
– Newborn: 160–450 units/L.
– Isoenzymes, adult or elderly:
– LDH-1: 17–27%.
– LDH-2: 27–37%.
– LDH-3: 18–25%.
– LDH-4: 3–8%.
– LDH-5: 0–5%.
Elevated LDH levels may indicate various health conditions, including diseases affecting red blood cell formation or early destruction of red blood cells, diseases or injuries causing muscle tissue damage, intestinal ischemia (injury to the intestines due to poor blood supply), pancreatitis (inflammation or infection of the pancreas), shock, infection, and severe dehydration.
Several factors and conditions can affect LDH levels, and the healthcare provider will consider these while making an accurate diagnosis. Factors such as strenuous exercise before the test or the use of certain medications or substances can influence LDH levels.
It is important to discuss the test results and their implications with your healthcare provider. You may want to inquire about the timing of result availability, how you will receive the results, available treatment options, the need for additional tests, and the recommended next steps based on the findings.
In summary, the LDH test assesses the level of lactic dehydrogenase in the blood and helps identify potential tissue damage due to various conditions. Discussing the results with your healthcare provider is essential for a comprehensive understanding of your health status and any necessary follow-up actions.
Please note that the information provided in this summary is not intended to replace professional medical advice. Always consult with your healthcare provider for personalized guidance and recommendations regarding your health.
