Lactate dehydrogenase test is ordered by the doctor to measure the level of LDH enzymes in the body. Read on more about this test as well as the importance of LDH enzyme in the body, by going through the following health care article.
People suffering from heart ailments, muscle injury, kidney disease, liver disorders, muscular dystrophy and many other health conditions are often requested to undergo a lactate dehydrogenase test by their doctor. This makes one wonder what does lactate dehydrogenase test mean and how is it related to their health. In this HealthHearty article, we shall have a look at information related to lactate dehydrogenase test and know how its elevation and deficiency affects one’s overall health.
What is Lactate Dehydrogenase?
Lactate dehydrogenase is an enzyme that is present in almost each and every body tissue. It is also called lactic acid dehydrogenase or LDH. This enzyme is very important during cellular respiration that helps in conversion of glucose into an ATP, that is, usable form of cellular energy. LDH is found in high levels in the cells, but it is present in low levels in the bloodstream. Lactate dehydrogenase elevation occurs due to tissue breakdown that causes the enzyme to be released in high levels into the blood stream. Conditions that can lead to this elevation include hemolysis, that is, tissue breakdown. Lactate dehydrogenase deficiency may be seen due to a genetic defect or when one consumes a large amount of ascorbic acid, that is, vitamin C, in their diet.
Lactate Dehydrogenase Mechanism
Lactate dehydrogenase is important for the body because it helps in the conversion of pyruvate and lactate, as well as the conversion of NADH and NAD+ at the same time. Pyruvate is the final product of glucolysis converted to lactate. This occurs when there is lack of oxygen in the body. This is a reverse reaction that occurs in the liver. When the amount of lactate is high in the body, enzyme inhibition occurs and the conversion of pyruvate into lactate decreases. When high levels of lactate dehydrogenase are observed, it indicates tissue injury somewhere in the body.
Why is Lactate Dehydrogenase Test Performed?
LDH test is performed to check tissue damage in the body. This tissue damage may occur in the heart, liver, kidney, skeletal muscles, blood cells, lungs and even the brain. Many times, patients suffering from other health conditions like megaloblastic anema, pernicious anemia, vitamin B12 deficiency causing anemia may also require LDH test to be conducted.
How is Lactate Dehydrogenase Test Performed?
Before the test, one may be asked to stop taking drugs like aspirin, clofibrate, mithramycin, narcotics, etc. that cause elevation of LDH. On the day of the test, the doctor or the phlebotomist will take blood sample from the vein or in some cases from the earlobe, heel, finger or toe. This blood sample will be analyzed in the laboratory with the help of a centrifuge machine. This helps in separating the cells from the blood serum. The blood serum will be used to measure the LDH levels.
What are the Normal Levels for LDH?
The normal levels of LDH enzyme in the blood range from about 105 – 333 IU/L. The normal value ranges tend to range slightly different in different laboratories. Thus, it is always a good idea to discuss your report with your doctor, before jumping to any conclusion.
What do the Abnormal Readings of LDH Indicate?
When the blood test results are back with abnormally high lactate dehydrogenase levels, it may indicate a number of health problems. These health problems include myocardial infarction (heart attack), cancer, meningitis, encephalitis, HIV, dysgerminoma, cerebrovascular trauma (stroke), presence of drugs like aspirin, anesthetics, alcohol, hemolytic and pernicious anemia, infectious mononucleosis, intestinal infarction, kidney or liver disease, pancreatitis and muscular dystrophy.
When the results are back with raised LDH levels, the doctor will understand tissue damage has occurred somewhere within the body. In order to find the exact location of tissue damage, the doctor will further advice LDH isoenzymes test. This test helps in differential diagnosis to determine which organ is involved for release of high levels of LDH in the bloodstream. If one is ordered LDH test, you will know it is to monitor any kind of muscle trauma or injury or anemia within the body.
