Lactate Dehydrogenase (LDH)

Methodology: 
The LD procedure employs a modification of the method of Wacker et al. which utilizes the forward reaction of lactate to pyruvate. Lactate and NAD are converted to pyruvate and NADH catalyzed by LD. NADH strongly absorbs light at 340 nm, whereas NAD does not. The rate of change of absorbance at 340 nm is directly proportional to the LD activity in the sample.
Performed: 
Monday - Friday
Reported: 
Within 24 hours
Purpose and principle: 
Elevations in serum lactate dehydrogenase (LD) occur from myocardial infarction, liver disease, pernicious and megaloblastic anemias, pulmonary emboli, malignancies, and muscular dystrophy.  A combined analysis of LD and CK (creatine kinase) isoenzymes provides a definite diagnosis of acute myocardial infarction.
Specimen Requirements: 

Type: Peripheral blood

Container/Tube:
  • Serum, gel
  • Plasma, gel

Sample Volume: 0.5mL

Stability (collection to time of analysis/testing):
  • Ambient: ASAP
  • Refrigerated: Not recommended
  • Frozen: Not recommended
Unacceptable Conditions: Moderate or gross hemolysis
Reference Values: 
140 – 271 U/L
CPT Code (s): 
83615
Notes: 

UFHPL Test #: 20290

UFHPL Epic order code: LAB96

Collection procedure: 
Serum gel tubes should be centrifuged within 2 hours of collection.
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