Lactate Dehydrogenase (LDH) is an enzyme found in almost all body tissues (heart, liver, muscles, kidneys, lungs, blood cells).

It plays a role in converting lactate to pyruvate in cellular metabolism.

Clinical uses include:

Detecting tissue damage or cell breakdown.

Supporting diagnosis of hemolytic anemia.

Monitoring liver disease, myocardial infarction, and muscle injury.

Assessing cancer progression or treatment response (e.g., lymphoma, germ cell tumors).

LDH is non‑specific, so it is usually interpreted alongside other tests.

Analyte: Serum LDH enzyme activity (U/L).

Normal Range (varies by lab): ~140–280 U/L.

Abnormal Findings:

High LDH: Tissue damage, hemolysis, liver disease, myocardial infarction, muscle injury, cancers.

Low LDH: Rare, may occur in genetic LDH deficiency.

Clinical Use:

Provides a general marker of tissue injury.

Helps guide diagnosis and monitoring of hemolysis, liver disease, and malignancies.

Supports critical care and oncology evaluations.