Start Date
Expiration Date
CPT Codes
Main Lab
Reference Test
ATLAS Test Code

Specimen Information


Cerebrospinal fluid (sterile container ONLY)
Pleural fluid, Pericardial fluid, Peritoneal fluid, Synovial fluid (Prefer fluid transferred to Gold, SST for transport, sterile container acceptable)


2.0 ml

Transport Info


Fasting Required?
Patient Instructions

Reference Range

Fluid LD activity is normally much less than the plasma LD activity.
Fluid LD activity near equal to the serum activity is usually associated with inflammatory processes.
Physician must interpret results based upon origin of fluid and patient's clinical condition.


Enzymatic Rate

Clinical Significance

Elevations are found in cardiac disease including myocardial infarction, liver diseases including cirrhosis and alcoholism, neoplasia, infectious mononucleosis, hypothyroidism, lung diseases, diseases of central nervous system, infections, inflammatory states, hemolytic anemia, megaloblastic anemia including pernicious anemia, muscular damage, muscular dystrophy, collagen disease • High levels occur with renal infarct, without significant elevation of AST, ALT, or alkaline phosphatase.

LD is found in all cells of the body, with extremely high levels found in specific tissues such as the heart, liver, kidneys, skeletal muscle, and erythrocytes. Therefore, increased levels seen in the serum can be directly related to damage of one of these tissues. Tissue levels of LD are 500-fold higher than whole blood levels. Total LD can be used to differentiate myocardial infarction, in which total LD is three to four times normal, from angina and periocarditis, in which LD levels are normal. Serous fluids for laboratory examination are collected by needle aspiration from body cavities. These aspiration procedures could include thoracentesis (pleural), pericardiacentesis (pericardial), synovial (joint) fluid and paracentesis (peritoneal). Many pathologic conditions can cause a buildup (effusion) of serous fluids. Effusion of serous fluid can be placed into two general categories: transudates and exudates. A transudate disrupts the balance in the regulation of fluid filtration and reabsorption. An example is the changes in hydrostatic pressure created by congestive heart failure. Exudates are produced by conditions that directly involve the membranes of the particular cavity including infections and malignancies. Analysis of body fluid usually includes one or more of the following: cell count, differential, total protein, crystals, pH, specific gravity, glucose, albumin, amylase, sodium, potassium, chloride, LD, creatinine, urea nitrogen, uric acid, routine culture, and cytologic studies. Additional testing may include specialized microbiology cultures for AFB or fungus or testing for the presence of bilirubin. Only those tests that are ordered will be performed.