Patient fasting is not required, however, in conditions where triglyceride values provide a priori diagnostic information, such as screening for familial hypercholesterolemia or early onset heart disease, pancreatitis, or confirming hypertriglyceridemia, the patient should be counseled to fast 12 to 14 hours prior to blood draw.
Collect specimen in plain red-top, green-top (heparin-no gel), or lavender-top (EDTA-no gel) tubes. Serum or plasma drawn in gel-barrier collection tubes should not be used. Gently invert tube 8 to 10 times to mix contents and allow specimen to clot for 30 minutes upright at room temperature prior to centrifugation (Plasma tubes should not clot). Centrifuge specimen within two hours of collection at 1800xg for 10 to 15 minutes to separate serum/plasma from the red cells and to avoid red cell contamination during shipment. If the sample cannot be centrifuged immediately, the sample should be refrigerated (at 2ºC to 8ºC) and centrifuged within 24 hours of collection. All specimens should be centrifuged by the client, prior to shipment to LabCorp, to ensure sample integrity. Immediately after centrifugation, pipette separated red-top serum or green-top/lavender-top plasma into a transport tube and label accordingly (serum, heparin plasma, EDTA plasma). Keep samples refrigerated until shipment to the laboratory and ship with frozen cool packs. Do not store at room temperature. Do not freeze the sample.
Refrigerate all acceptable tube types as soon as possible after centrifugation and within 24 hours of collection. Keep refrigerated prior to shipment, and ship on frozen cool packs. Do not store at room temperature. Do not freeze the sample. Sample is stable refrigerated for six days.
If triglyceride level is >400 mg/dL, LDL cholesterol will not be calculated.
Test measures LDL and HDL particle size and number of LDL particles. A lipid profile is also included based on NMR-derived lipid values. Medicare coverage is provided; contact private insurance carriers for coverage. LDL particle number and size are similar for fasting and non-fasting specimens; however, triglycerides and VLDL results will be significantly higher with non-fasting samples.