Test Code LDL DIRECT Low-Density Lipoprotein (LDL) Cholesterol, Beta-Quantification, Serum
Additional Codes
Mayo Test ID |
---|
LDLD |
Reporting Name
LDL Cholesterol (Beta-Quant), SUseful For
Evaluation of cardiovascular risk
Verification of estimated low-density lipoprotein cholesterol (LDL-C) in patients with hypertriglyceridemia or extremely low LDL-C
Diagnosis of familial hypobetalipoproteinemia and abetalipoproteinemia
Performing Laboratory
Mayo Clinic Laboratories in RochesterSpecimen Type
SerumNecessary Information
Indicate patient's age and sex.
Specimen Required
Collection Container/Tube:
Preferred: Serum gel
Acceptable: Red top
Submission Container/Tube: Plastic vial
Specimen Volume: 3 mL
Collection Instructions: Centrifuge and aliquot serum into plastic vial. Send refrigerated.
Specimen Minimum Volume
2 mL
Specimen Stability Information
Specimen Type | Temperature | Time | Special Container |
---|---|---|---|
Serum | Refrigerated (preferred) | 10 days | |
Frozen | 60 days |
Reference Values
The National Lipid Association and the National Cholesterol Education Program (NCEP) have set the following guidelines for LDL-C in adults (ages 18 years and up):
Desirable: <100 mg/dL
Above desirable: 100-129 mg/dL
Borderline high: 130-159 mg/dL
High: 160-189 mg/dL
Very high: ≥190 mg/dL
The Expert Panel on Integrated Guidelines for Cardiovascular Health and Risk Reduction in Children and Adolescents has set the following guidelines for LDL-C in children and adolescents (ages 2-17 years):
Acceptable: <110 mg/dL
Borderline high: 110-129 mg/dL
High: ≥130 mg/dL
Day(s) Performed
Monday through Thursday; Saturday, Sunday
CPT Code Information
83701
LOINC Code Information
Test ID | Test Order Name | Order LOINC Value |
---|---|---|
LDLD | LDL Cholesterol (Beta-Quant), S | 18261-8 |
Result ID | Test Result Name | Result LOINC Value |
---|---|---|
LDLC | LDL Chol (Beta-Quantification), S | 18261-8 |
Test Classification
This test has been modified from the manufacturer's instructions. Its performance characteristics were determined by Mayo Clinic in a manner consistent with CLIA requirements. This test has not been cleared or approved by the US Food and Drug Administration.Clinical Information
Low-density lipoprotein cholesterol (LDL-C) is acknowledged as being causally related with atherosclerotic cardiovascular disease. LDL-C remains the primary focus for cardiovascular risk assessment and effectiveness of risk reduction interventions including diet, physical activity, and pharmacologic therapies.
Low-density lipoproteins are a heterogeneous population of lipid particles classically defined as having a density of 1.006 to 1.063 kg/L obtained by preparative ultracentrifugation. The gold standard beta-quantification (beta-quant or BQ) method combines ultracentrifugation with precipitation and yields a direct quantitative measurement of LDL-C, intermediate-density lipoprotein cholesterol, and lipoprotein(a) cholesterol.
Extremely low concentrations of LDL-C are associated with abetalipoproteinemia and hypobetalipoproteinemia. In both cases, individuals will have very low total cholesterol and diminished or absent LDL-C, apolipoprotein B, and very low-density lipoprotein cholesterol. Patients may exhibit clinical signs and symptoms of polyneuropathy, intestinal fat malabsorption, hepatosteatosis, and fat-soluble vitamin deficiencies.
Interpretation
Mayo Clinic has adopted the National Lipid Association classifications, which are included as reference values on Mayo Clinic and Mayo Clinic Laboratories reports (see Reference Values). Lipids are most commonly measured to assess cardiovascular risk. Maintaining desirable concentrations of lipids lowers the risk of heart attacks or strokes.
Establishing appropriate treatment strategies and lipid goals requires consideration of low-density lipoprotein cholesterol (LDL-C) in context with other risk factors including age, sex, smoking status, family and personal history of heart disease. All guidelines recommend aggressive lipid lowering for patients with LDL cholesterol above 190 mg/dL.
Values below 20 mg/dL in untreated patients may be consistent with hypobetalipoproteinemia. Complications due to fat malabsorption may be present in affected individuals.
Undetectable LDL-C is highly suggestive of abetalipoproteinemia. Related polyneuropathy may exist in affected individuals.
Cautions
Result can be falsely decreased in patients with elevated levels of N-acetyl-p-benzoquinone imine (NAPQI)-a metabolite of acetaminophen), N-acetylcysteine (NAC), and metamizole.
Report Available
2 to 4 daysReject Due To
Gross hemolysis | Reject |
Gross lipemia | OK |
Gross icterus | Reject |
Method Name
Ultracentrifugation/Selective Precipitation/Enzymatic Colorimetric
Forms
If not ordering electronically, complete, print, and send a Cardiovascular Test Request Form (T724) with the specimen.