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Test ID LDLD Low-Density Lipoprotein (LDL) Cholesterol, Beta-Quantification, Serum

Reporting Name

LDL Cholesterol (Beta-Quant), S

Useful 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

Specimen Type


Necessary 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


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.


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.


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.

Clinical Reference

1. Expert Panel on Detection, Evaluation, and Treatment of High Blood Cholesterol in Adults: Executive Summary of the Third Report of the National Cholesterol Education Program (NCEP) Expert Panel on Detection, Evaluation, and Treatment of High Blood Cholesterol in Adults (Adult Treatment Panel III). JAMA. 2001 May 16;285(19):2486-2497

2. Jacobson TA, Ito MK, Maki KC, et al: National Lipid Association recommendations for patient-centered management of dyslipidemia: part 1 - executive summary. J Clin Lipidol. 2014 Sep-Oct;8(5):473-488

3. Expert panel on integrated guidelines for cardiovascular health and risk reduction in children and adolescents: summary report. Pediatrics. 2011 Dec;128(Suppl 5):S213-S256

4. Grundy SM, Stone NJ, Bailey AL, et al: 2018 AHA/ACC/AACVPR/AAPA/ABC/ACPM/ADA/AGS/APhA/ASPC/NLA/PCNA Guideline on the Management of Blood Cholesterol: Executive Summary: A Report of the American College of Cardiology/American Heart Association Task Force on Clinical Practice Guidelines. Circulation. 2019 Jun 18;139(25):e1046-e1081. doi: 10.1161/CIR.0000000000000624

Method Description

Serum is combined with dextran sulfate and magnesium, ions precipitate the low-density lipoprotein and very low-density lipoprotein fractions, leaving the high-density lipoprotein (HDL) fraction in solution. The HDL cholesterol is then determined using an enzymatic cholesterol assay.(Package insert: HDL Cholesterol Precipitating Reagent Set [Dextran Sulfate]; Pointe Scientific, Inc; 12/2009)


Cholesterol esters are cleaved by the action of cholesterol esterase to yield free cholesterol and fatty acids. Cholesterol oxidase then catalyzes the oxidation of cholesterol to cholest-4-en-3-one and hydrogen peroxide. In the presence of peroxidase, the hydrogen peroxide formed effects the oxidative coupling of phenol and 4-aminophenazone to form a red quinone-imine dye. The color intensity of the dye formed is directly proportional to the cholesterol concentration. It is determined by measuring the increase in absorbance.(Package insert: Cholesterol Gen2 Reagent. Roche Diagnostics; V 13.0, 02/2019)

Report Available

2 to 4 days

Reject Due To

Gross hemolysis Reject
Gross lipemia OK
Gross icterus Reject

Method Name

Ultracentrifugation/Selective Precipitation/Enzymatic Colorimetric


If not ordering electronically, complete, print, and send a Cardiovascular Test Request Form (T724) with the specimen.