LDH Lactic acid dehydrogenase muscle damage? (LD)
Overtrained? Lactate dehydrogenase, LDH, lactic acid dehydrogenase.
This test measures the amount of lactate dehydrogenase (LDH) in the blood. LDH is an enzyme found in most tissues in the body and required for the conversion of lactate. It is mainly present in tissue cells and normally the amount in the blood is low. When a tissue or organ is damaged, LDH enters the blood from the tissue cells and an elevated LDH can be measured. LDH can therefore be used to investigate whether tissue and the cells of the tissue are damaged. The LDH may also be elevated after internal bleeding.
LDH has a number of so-called isoenzymes, which are enzymes with the same function (breakdown of lactate), which differ slightly depending on the type of tissue. Therefore, in special cases the determination of isoenzymes can give an indication of the type of tissue that has been damaged. In general, however, there are other examinations, which give faster and more sensitive information about the affected tissues or organs.
The main application of the measurement of LDH is to investigate whether there is tissue damage (acute or long-term) or the disintegration of red blood cells. The severity of the damage can also be determined. In addition, the test is used to monitor decay and recovery of tissue.
An LDH determination can also provide information about damage to cardiac tissue. However, other substances that enter the blood during a myocardial infarction (such as troponin and and CK) can be measured in the blood faster than LDH after an infarction.
An elevated LDH means that cells of tissue have been destroyed. When tissue damage has occurred, LDH will be measurable in blood after some time. Elevated values are found in all diseases where a tissue or organ is damaged. Also when red blood cells are destroyed the LDH will be increased.