lactate dehydrogenase

Meaning of lactate dehydrogenase: Lactate dehydrogenase is an enzyme active in nearly all body tissues, and its blood level rises with cell injury from a wide range of causes.

Definition of lactate dehydrogenase

Lactate dehydrogenase, often abbreviated LDH, is an enzyme that catalyzes the reversible conversion of lactate to pyruvate, a step in the pathway cells use to produce energy when oxygen is limited. It is present in nearly every tissue of the body, including the heart, liver, kidney, skeletal muscle, lung, and red blood cells.

Because the enzyme is so widely distributed, a raised level in the blood does not identify a single organ or disease by itself. It commonly rises with tissue damage from a heart attack, muscle injury, liver disease, infection, or the breakdown of red blood cells, and certain cancers raise it as well through rapid cell turnover.

Lactate dehydrogenase exists as several isoenzymes formed from different combinations of protein subunits that are distributed unevenly across organs, and laboratories sometimes examine this isoenzyme pattern rather than the overall level to help narrow down which tissue is responsible.

Also known as

lactic acid dehydrogenaseLDH

Used in a sentence

The physician reviewed the patient's lactate dehydrogenase level along with other laboratory findings before determining the next step in evaluation.

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Good to know

Because lactate dehydrogenase is present in so many tissues, an elevated level is generally treated as a nonspecific marker of cell turnover or injury rather than proof of any one condition.

Word origin

Where “lactate dehydrogenase” comes from

Formed from Latin lac, lactis, meaning milk, the root of lactate, combined with dehydrogenase, from de-, meaning removal, and hydrogen, with the enzyme suffix -ase, meaning an enzyme that removes hydrogen atoms during a reaction.

For learning, not diagnosis. This glossary provides general educational information and is not a substitute for advice from a qualified healthcare professional. If you may be experiencing a medical emergency, contact local emergency services.