Miscellaneous Lactate Dehydrogenase

Test Code

CPT Codes

Preferred Specimen

Body fluid specimen, including but not limited to: Cerebrospinal Fluid, pleural fluid, pericardial fluid, peritoneal fluid, or synovial fluid. Note fluid type in order comments or on patient specimen label.

Minimum Volume
1 mL


Collect body fluid in a body fluid collection bag or other sterile container and transport to lab. Refrigerate if transport will be delayed. Note fluid type in order comments or on patient specimen label.

This test is for Lactate Dehydrogenase measurement on body fluids.  For Lactate Dehydrogenase measurement on serum or plasma, order LDH.

Transport Container

Body fluid collection bag or sterile container

Transport Temperature
Room Temperature or Refrigeration

Specimen Stability
Room Temperature - 4 hours; Refrigerated - 24 hours

Reject Criteria (Eg, hemolysis? Lipemia? Thaw/Other?)
Gross viscosity or turbidity


Setup Schedule

Daily upon receipt

Report Available
Upon completion of analysis

Gross viscosity or turbidity may interfere with testing.

Clinical Significance

Lactate dehydrogenase is an enzyme that is used by cells in metabolism and production of energy. When there is a large presence of cells and cell death such as in infection and inflammation the concentration of LDH in the area increases. Transudates will have LDH levels lower than 200 units/L while exudates will have LDH levels higher than 200 units/L. Another way of assessing the levels of LDH in fluid is to compare it to the concentration of LDH in serum. Transudates will have a fluid to serum ratio of LDH lower than 0.6 while exudates will have a ratio of fluid to serum LDH that is higher than 0.6.

The CPT Codes provided in this document are based on AMA guidelines and are for informational purposes only. CPT coding is the sole responsibility of the billing party. Please direct any questions regarding coding to the payor being billed. Any Profile/panel component may be ordered separately. Reflex tests are performed at an additional charge.