Test Code LAB102 LDL, Direct (Low Density Lipoprotein)
Performing Laboratory
Asante Rogue Regional Medical Center (ARRMC)
Performing Department
Chemistry
Specimen Required
Outpatient clients MUST draw SST
Specimen Minimum Volume
2.0 mL
Specimen Stability Information
Tubes of blood should be kept closed at all times in a vertical, stopper-up postion. Serum or plasma should be separated from contact with cells as soon as possible. A maximum limit of 2 hours from the time of collection is recommended.
Separated serum should not remain at 15° to 30° C longer than 8 hours. If assays are not completed within 8 hours, serum should be stored at 2° to 8°C. If assays are not completed within 48 hours, or the separated sample is to be stored beyone 48 hours, samples should be frozen at 15° to 20°C. Frozen samples should be thawed only once. Analyte deterioration may occur in samples that are repeatedly frozen and thawed.
Reject Due To
- Icterus
- Lipemia
- Hemolysis
- Quantity not sufficient (QNS)
- Lack of Two Patient Identifiers:
- 1-Patient’s First & Last name
- 2-Patient’s Date of Birth
Day(s) Performed
Monday through Sunday
Method Name
Homogeneous detergent assay
CPT Code Information
83721
Lipoprotein, direct measurement; LDL cholesterol
Billing Code
2053171
Supportive Data
Medical trials and research have identified elevated LDL cholesterol as a major cause of coronary heart disease (CHD). Recent clinical studies have shown that LDL-lowering therapy reduces risk for CHD. For these reasons, LDL cholesterol is often the primary target of cholesterol-lowering therapy.
Note: Previous to the introduction of direct methods, the only way to easily estimate the LDL fraction was to measure total cholesterol, HDL and triglycerides and calculate LDL by the Friedenwald equation:
Total cholesterol – HDL – (Trig/5). Direct LDL methods allow the analysis of LDL alone. In addition, high triglyceride values and non-fasting patients can have erroneous LDL values when calculated by the Friedenwald equation.