: Lactate Dehydrogenase, Serum or Plasma

: What Is Lactate Dehydrogenase?

: Lactate dehydrogenase is an enzyme involved in energy production that is present in nearly all cells of the body, including the heart, liver, muscles, kidneys, and red blood cells. When cells are damaged or destroyed, they release LDH into the bloodstream, so the amount in your blood can rise.

: Why This Test Is Ordered

: Your healthcare provider may order an LDH test to look for evidence of tissue damage, to help monitor a known condition, or as part of a broader panel of tests. It is a general indicator and is usually interpreted alongside other test results and your symptoms.

: How the Sample Is Collected

: The test is performed on a blood sample, typically serum or plasma, drawn from a vein in your arm. No special preparation is usually required, though your provider will tell you if any fasting or other instructions apply.

: What Results Can Mean

: A higher-than-expected LDH level can occur with many different conditions, including liver disease, muscle injury, heart problems, anemia, and other illnesses. Because LDH is found throughout the body, an abnormal result does not by itself pinpoint the cause and is generally followed up with additional testing.