Triglyceride (TGL)

CPT Code: 84478
Specimen: Serum or Plasma
Volume: 1 mL
Minimum Volume: 0.5 mL
Container:

Red-top tube, gel-barrier tube, green-top (heparin) tube, or lavender-top (EDTA) tube.

Blood collection tubes containing glycerol lubricated stoppers should be avoided since they will cause erroneously elevated results.

Methodology: Enzymatic
Collection: Separate serum or plasma from cells within 45 minutes of collection.
Reference Range: 0-149 mg/dL

Stability: 

Temperatures Period
Room Temperature 8 Hours
Refrigerated (2-8 ⁰C)  2 Days
Frozen (≤ -20 ⁰C) Longer Storage

 

Use: Triglycerides are fatty molecules formed in the liver and make up 95% of fat stored in tissue. Their major function is to provide energy. Triglycerides are often elevated after a meal; therefore, at least a 12-hour fast is required to obtain meaningful triglyceride results.  When serum triglyceride and cholesterol levels are both elevated, the risk for coronary heart disease increases.
Clinical Significance: High levels may occur with hypothyroidism, nephrotic syndromes, carbohydrate-sensitive hypertriglyceridemia, glycogen storage disease, and in hyperlipoproteinemias type I, IIb, III, IV, and V. Some alcoholics have hypertriglyceridemia which disappears with abstinence. Extremely high triglyceride levels may occur with alcohol abuse. Triglyceride is needed for calculation of LDL-C (low-density lipoprotein cholesterol) concentration. Disturbances in triglyceride metabolism relate to diabetes and are a risk factor for atherosclerotic disease, but not an independent one.
Causes for Rejection: Specimen collected in a glycerinated tube; improper labeling
Interfering Substances: Small amounts of free glycerol may be found in blood samples from healthy individuals due to natural lipolysis.  The concentration of free glycerol may be increased by stress, disease states or administration of intravenous infusates.  Free glycerol or other polyols may cause a positive interference. 

Hemoglobin (hemolysate) of 500 mg/dL (monomer) will increase a triglycerdies result of 155 mg/dL by 12%.

Bilirubin (unconjugated) of 20 mg/dL will increase triglycerides result of 156 mg/dL by 11%.