Lactate Dehydrogenase (LDH) is a protein, a key compound for cell energy production. Cellular respiration occurs when sugar in glucose form is turned into a type of energy molecule that cells can translate into movement. In this process, LDH is the enzyme that transforms energy for cell use.
In cases of tissue damage, the cells drop LDH into the bloodstream and other corporal fluids. This happens in heart muscle cells, the lungs, the kidneys, the liver, the muscles, the brain, and even the blood.
Why would a doctor test your LDH levels?
A doctor may order a lactate dehydrogenase test when there is suspicion of tissue damage, especially in vital organs, or in case of suspecting other conditions that feature organic injuries or significant cell destruction.
Since LDH levels rise due to a wide variety of conditions, the cause of a high LDH level in the blood is not often clear. This test is frequently used as a non-specific indicator of organ injury or cell destruction and ordered, among other tests, to offer more insight into the actual illness.
The sample is usually blood drawn from a vein, probably at the elbow, but it also can be tested from the lung fluids or the spinal cord and, less commonly, from the cerebrospinal fluid or the urine.
A health care specialist may ask for an LDH test from a blood sample in cases of severe conditions and serious diseases such as bone fractures, heart attack, hepatitis, stroke, lung cancer, testicular or ovarian cancer, septic shock, lymphoma, melanoma, or leukemia. An additional test from other body fluids may be more specific and related to the particular illness.
Besides the conditions mentioned above, high LDH levels may confirm cell damage in cases of hypoxia, anemia, acute muscle injury, pancreatitis, HIV, meningitis, mononucleosis, and other chronic conditions. High levels of LDH could be a sign that chemotherapy is not practical.
Extremely high LDH levels can be a terrible indicator in patients with a poor prognosis, as in cases of AIDS or multiple organ failure.
Some bacteria produce lactate dehydrogenase spontaneously as well.
The lactate dehydrogenase test is then significant due to the cellular or tissue damage detection and to evaluate the progress of a particular treatment and obtain a prognosis. This is particularly true in the case of cancer patients.