Lactate Dehydrogenase (LDH) Activity in Serum or Plasma

What Is LDH Used For?

LDH is often checked alongside other tests like creatine kinase (CK) or alanine aminotransferase (ALT) to help diagnose conditions such as heart attacks, muscle injuries, liver disease, or certain cancers. Elevated levels may suggest widespread tissue damage, while lower levels could indicate certain metabolic or genetic disorders.

How Is the Test Performed?

A blood sample is drawn from a vein in your arm. The blood is then processed to separate serum or plasma, and the LDH activity is measured using an enzymatic method that detects its ability to convert lactate to pyruvate over time.

Why Might You Need This Test?

Your healthcare provider may order LDH testing if you have symptoms like chest pain, muscle weakness, fatigue, or unexplained bruising, or if you have a known condition that could affect LDH levels, such as heart disease, liver disease, or anemia.

What Do Results Mean?

Results are not provided with specific reference ranges, as they depend on the clinical context and other factors. Elevated LDH levels may signal tissue injury or disease, while normal or low levels do not definitively rule out any condition. Your doctor will interpret results in relation to your symptoms and medical history.