Hey everyone, Abby, here from nursing.com. This lesson will discuss lactate dehydrogenase. We’ll talk about the normal levels and conditions that might increase or decrease its value. Let’s get started. 

Lactate Dehydrogenase or LDH, is a lab that measures the amount of LDH in the blood. LDH is present in almost every single tissue in the body. It gets released into the bloodstream when that tissue becomes damaged. We see that with myocardial infarction. 

Some clinical indications for having this lab drawn are in cases of hemolysis. I used to work with ECMO patients and through the oxygenator, as those cells would go through the motor and the whole circuit and everything, sometimes they would get really chewed up, and it was evidence of a lot of hemolysis, and so we would use that LDH value to tell us just how much that might be happening. It’s also indicated for patients with hemolytic anemia. It’s also going to be drawn to evaluate for ischemic organ damage like we talked about on that first slide. You can see here, after an MI, this section of tissue that became ischemic and died. Normal therapeutic values are between 88 and 230 units per liter. It’s collected in a plasma separator tube like this green top. 

When blood values are increased in LDH, that can indicate liver disease and pancreatitis. We talked about hemolytic disorders and myocardial infarction, but also bone fractures, muscle trauma, and let’s not forget anaerobic metabolism. It’s also one of the standard labs that are drawn when tumor lysis syndrome is suspected. In infections like encephalitis, bacterial meningitis, and HIV, an LDH value will also be increased. Now, it’s not very typical for there to be an LDH deficiency. It’s pretty rare and it’s not considered harmful or related to any disease process so, that’s some good news. LDH is an enzyme or byproduct of tissue damage that can be seen in anaerobic metabolism, hemolysis, MI, pancreatitis, liver, heart, brain, all of these various tissue diseases, right? It’s an indication of ischemia or damage. Normal values are between 88 and 230 units per liter. When it’s decreased, that’s pretty rare and unrelated to a disease process. 

Now, you all did great, and this wraps up our lesson on lactate dehydrogenase. Remember, we love you guys, now go out and be your best self today and as always, happy nursing.

References:

• https://ltd.aruplab.com/Tests/Pub/0020006
• https://www.uptodate.com/contents/approach-to-the-patient-with-abnormal-liver-biochemical-and-function-tests?search=LDH%20lab&sectionRank=1&usage_type=default&anchor=H58137036&source=machineLearning&selectedTitle=2~150&display_rank=2#H58137036
• https://www.uptodate.com/contents/image?topicKey=GAST%2F3576&view=machineLearning&search=LDH%20lab&sectionRank=1&usage_type=default&imageKey=GAST%2F98392&rank=2~150&source=machineLearning&display_rank=2
• https://www.uptodate.com/contents/lactate-dehydrogenase-deficiency?search=LDH%20lab&source=search_result&selectedTitle=1~150&usage_type=default&display_rank=1#H3
• https://www.uptodate.com/contents/biomarkers-of-myocardial-injury-other-than-troponin?search=LDH%20lab&sectionRank=1&usage_type=default&anchor=H8&source=machineLearning&selectedTitle=7~150&display_rank=7#H8