As I mentioned in my previous post on " Liver Function Tests: An Overview", here I will discuss how the results of Lactate Dehydrogenase testing can be used to evaluate liver (dys)function. Some details may not be mentioned; more detailed posts will be coming soon.
The basics of Lactate Dehydrogenase
LDH is widely distributed throughout body; NOT at all specific to liver!
Electrophoresis separates it into 5 diff isoenzymes (see separate post for full details)
Elevated LD4 & LD5 suggest liver damage (or skeletal muscle injury)
Testing for LD4/LD5 is NOT routinely done in clinical practice as there are much better tests/indicators of liver function/damage
Elevated LD activity
Total LD activity is a commonly performed test (not specifically done for liver). I like to think of LDH elevations being a sign of some anaerobic process occurring. Thus, elevations can be seen in any disease where there is a problem getting oxygen to the tissue-. Some examples include:
Problems in the blood: Hemolysis, Megaloblastic anemia
Problems in the tissue: Muscle, Liver, Kidney, Lung disorders
Neoplasms "hogging" or "destroying" the natural order- Leukemias/Lymphomas, Some Carcinomas
As always, a disclaimer that this is NOT medical advice... consult your physician, medical literature etc before making any assumptions from this article
Reference: Daniel D. Mais, MD. "Practical Clinical Pathology". pg 1. Amer Soc for Clin Path. 2014.