Cholesteryl Esters, Serum
NY State Approved Indicates the status of NY State approval and if the test is orderable for NY State clients.
Establishing a diagnosis of lecithin-cholesterol acyltransferase deficiency
Evaluating the extent of metabolic disturbance by bile stasis or liver disease
Reporting Name A shorter/abbreviated version of the Published Name for a test; an abbreviated test name
Cholesteryl Esters, S
Specimen Type Describes the specimen type needed for testing
Specimen Required Defines the optimal specimen. This field describes the type of specimen required to perform the test and the preferred volume to complete testing. The volume allows automated processing, fastest throughput and, when indicated, repeat or reflex testing.
Preferred: Red top
Acceptable: Serum gel
Submission Container/Tube: Plastic vial
Specimen Volume: 1 mL
1. Fasting-overnight (12-14 hours).
2. Patient must not consume any alcohol for 24 hours before the specimen is drawn.
Specimen Minimum Volume Defines the amount of specimen required to perform an assay once, including instrument and container dead space. Submitting the minimum specimen volume makes it impossible to repeat the test or perform confirmatory or perform reflex testing. In some situations, a minimum specimen volume may result in a QNS (quantity not sufficient) result, requiring a second specimen to be collected.
Mild OK; Gross reject
Mild OK; Gross OK
Mild OK; Gross reject
Specimen Stability Information Provides a description of the temperatures required to transport a specimen to the laboratory. Alternate acceptable temperature(s) are also included.
|Serum||Refrigerated (preferred)||7 days|
Clinical Information Discusses physiology, pathophysiology, and general clinical aspects, as they relate to a laboratory test
Cholesterol in the blood serum normally is 60% to 80% esterified with fatty acids, largely as a result of the action of the enzyme lecithin-cholesterol acyltransferase (LCAT), which circulates in the blood in association with the high-density lipoproteins. LCAT transfers an acyl group for lecithin to cholesterol.
Familial deficiency of LCAT is uncommon, usually occurring individuals of northern Europe descent, and is associated with erythrocyte abnormalities (target cells) and decreased (20% or less) esterification of plasma cholesterol. This is associated with early atherosclerosis, corneal opacification, hyperlipidemia, and mild hemolytic anemia.
Persons with liver disease may have impaired formation of LCAT and, therefore, a secondary deficiency of this enzyme and of esterified plasma cholesterol.
Reference Values Describes reference intervals and additional information for interpretation of test results. May include intervals based on age and sex when appropriate. Intervals are Mayo-derived, unless otherwise designated. If an interpretive report is provided, the reference value field will state this.
60-80% of total cholesterol
Reference values have not been established for patients that are <16 years of age.
In patients with lecithin-cholesterol acyltransferase deficiency, the concentration of unesterified cholesterol in serum may increase 2 to 5 times the normal value, resulting in a decrease in esterified serum cholesterol to 20% or less of the total serum cholesterol.
Cautions Discusses conditions that may cause diagnostic confusion, including improper specimen collection and handling, inappropriate test selection, and interfering substances
Cholesteryl ester storage disease in a severe form can be fatal before the age of 1 year (Wolman's disease), and in some cases may be undetected until adulthood in less severe forms. This defect is caused by a deficiency of a lysosomal enzyme, acid cholesteryl ester hydrolase (also known as acid lipase). It causes accumulation of cholesteryl esters in tissues, but it has no effect on the percentage of cholesterol that circulates in esterified form in the blood serum. Detection of the defect requires careful evaluation of the cholesteryl ester hydrolase activity and cholesteryl ester content of leukocytes, cultured fibroblasts, and liver biopsy.
Clinical Reference Provides recommendations for further in-depth reading of a clinical nature
Glomset JA, Assmann G, Gjone E, Norum KR: Lecithin: cholesterol acyltransferase deficiency and fish eye disease. In The Metabolic Basis of Inherited Disease. Seventh edition. Edited by CR Scriver, AL Beaudet, WS Sly, D Valle. New York, McGraw-Hill Book Company, 1995, pp 1933-1951
Method Description Describes how the test is performed and provides a method-specific reference
Unesterified (free) cholesterol is measured by direct analysis of serum using reagents supplied by Wako Chemicals USA, Inc., as adapted to an automated chemistry analyzer. Free cholesterol reacts with cholesterol oxidase to generate hydrogen peroxide which reacts with 3,5-dimethoxy-N-(2-hydroxy-3-sulfopropyl) aniline sodium (DAOS) and 4-aminoantipyrene to produce a blue pigment. The product is proportional to the serum free cholesterol concentration. The result is expressed as percent esterified cholesterol based on the total serum cholesterol concentration obtained by conventional assay.(Allain CC, Poon LS, Chan CSG, et al: Enzymatic determination of total serum cholesterol. Clin Chem 1974;20:470-475; package insert: Wako Free Cholesterol E. Wako Chemicals USA, Inc., Richmond, VA)
Day(s) and Time(s) Test Performed Outlines the days and times the test is performed. This field reflects the day and time the sample must be in the testing laboratory to begin the testing process and includes any specimen preparation and processing time required before the test is performed. Some tests are listed as continuously performed, which means assays are performed several times during the day.
Monday through Friday; 7 a.m.-5 p.m.
Analytic Time Defines the amount of time it takes the laboratory to setup and perform the test. This is defined in number of days. The shortest interval of time expressed is "same day/1 day," which means the results may be available the same day that the sample is received in the testing laboratory. One day means results are available 1 day after the sample is received in the laboratory.
Maximum Laboratory Time Defines the maximum time from specimen receipt at Mayo Medical Laboratories until the release of the test result
Specimen Retention Time Outlines the length of time after testing that a specimen is kept in the laboratory before it is discarded
Performing Laboratory Location The location of the laboratory that performs the test
Test Classification Provides information regarding the medical device classification for laboratory test kits and reagents. Tests may be classified as cleared or approved by the US Food and Drug Administration (FDA) and used per manufacturer's instructions, or as products that do not undergo full FDA review and approval, and are then labeled as an Analyte Specific Reagent (ASR), Investigation Use Only (IUO) product, or a Research Use Only (RUO) product.
This test uses a reagent or kit labeled by the manufacturer as Research Use Only. 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 U.S. Food and Drug Administration.
CPT Code Information Provides guidance in determining the appropriate Current Procedural Terminology (CPT) code(s) information for each test or profile. The listed CPT codes reflect Mayo Medical Laboratories interpretation of CPT coding requirements. It is the responsibility of each laboratory to determine correct CPT codes to use for billing.
LOINC® Code Information Provides guidance in determining the Logical Observation Identifiers Names and Codes (LOINC) values for the result codes returned for this test or profile.
|Result ID||Reporting Name||LOINC Code|
|CHLES||Cholesteryl Esters, S||21197-9|