Lactate dehydrogenase test
Definition
The lactate dehydrogenase (LDH) test measures the amount of LDH in the blood.
See also: LDH isoenzymes
Alternative Names
LDH test; Lactic acid dehydrogenase test
How the Test is Performed
A blood sample is needed. For information on how this isdone, see:Venipuncture
How to Prepare for the Test
Your health care provider may ask you to stop taking drugs that may affect the test. Drugs that can increase LDH measurements include anesthetics, aspirin, clofibrate, fluorides, mithramycin, narcotics, and procainamide.
Why the Test is Performed
LDH is most often measured to check for tissue damage. Theprotein LDH is in many body tissues, especially the heart, liver, kidney, muscles, brain, blood cells, and lungs.
Other conditions under which the test may be done:
- Anemia of vitamin B-12 deficiency
- Leukemia or lymphoma
- Megaloblastic anemia
- Pernicious anemia
Normal Results
A typical range is 105 - 333 IU/L (international units per liter).
The examples above are common measurements for results of these tests. Normal value ranges may vary slightly among different laboratories. Some labs use different measurements or test different samples. Talk to your doctor about the meaning of your specific test results.
What Abnormal Results Mean
Higher-than-normal levels may indicate:
- Blood flow deficiency (ischemia)
- Cerebrovascular accident (such as a stroke)
- Heart attack
- Hemolytic anemia
- Infectious mononucleosis
- Liver disease (for example, hepatitis)
- Low blood pressure
- Muscle injury
- Muscular dystrophy
- New abnormal tissue formation (usually cancer)
- Pancreatitis
- Tissue death
If the LDH level is raised, your doctor may order an LDH isoenzymes test.
References
Gallagher PG. Hemolytic anemias: red cell membrane and metabolic defects In: Goldman L, Schafer AI, eds. Cecil Medicine. 24th ed. Philadelphia, Pa: Saunders Elsevier; 2011:chap 164.
Gregg X, Prchal JT. Red Blood Cell Enzymopathies. In: Hoffman R, Benz EJ, Shattil SS, et al, eds. Hematology: Basic Principles and Practice. 5th ed. Philadelphia, Pa: Elsevier Churchill Livingstone; 2008:chap 45.
Reviewed By: Todd Gersten, MD, Hematology/Oncology, Palm Beach Cancer Institute, West Palm Beach, FL. Review provided by VeriMed Healthcare Network. Also reviewed by Linda J. Vorvick, MD, Medical Director and Director of Didactic Curriculum, MEDEX Northwest Division of Physician Assistant Studies, Department of Family Medicine, UW Medicine, School of Medicine, University of Washington; David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.
