Establishing a diagnosis of lecithin-cholesterol acyltransferase deficiency
Evaluating the extent of metabolic disturbance by bile stasis
Enzymatic Colorimetric
Cholesterol Esters
Serum
Collection Container/Tube:
Preferred: Serum gel
Acceptable: Red top
Submission Container/Tube: Plastic vial
Specimen Volume: 1 mL
Collection Instructions: Centrifuge and aliquot serum into plastic vial. Send refrigerated.
If not ordering electronically, complete, print, and send a Cardiovascular Test Request Form (T724)
0.5 mL
Gross hemolysis | Reject |
Gross lipemia | OK |
Gross icterus | Reject |
Specimen Type | Temperature | Time | Special Container |
---|---|---|---|
Serum | Refrigerated (preferred) | 7 days | |
Frozen | 60 days | ||
Ambient | 24 hours |
Establishing a diagnosis of lecithin-cholesterol acyltransferase deficiency
Evaluating the extent of metabolic disturbance by bile stasis
Cholesterol in the blood serum is normally 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.
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 serum 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, an acquired LCAT deficiency and reduced cholesterol ester concentration.
> or =18 years: 60-80% of total cholesterol
Reference values have not been established for patients who are less than 18 years of age.
In patients with lecithin-cholesterol acyltransferase deficiency, the concentration of unesterified
In a severe form, cholesteryl ester storage disease can be fatal before the age of 1 year (Wolman's disease) and, in some less severe form cases, may be undetected until adulthood. 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.
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.
1. Meikle PJ, Mundra PA, Wong G, et al: Circulating lipids are associated with alcoholic liver cirrhosis and represent potential biomarkers for risk assessment. PLoS One. 2015 Jun 24;10(6):e0130346. doi: 10.1371/journal.pone.0130346
2. Leach NV, Dronca E, Vesa SC, et al: Serum homocysteine levels, oxidative stress and cardiovascular risk in non-alcoholic steatohepatitis. Eur J Intern Med. 2014 Oct;25(8):762-767. doi: 10.1016/j.ejim.2014.09.007
3. Santamarina-Fojo S, Hoeg JM, Assmann G, Brewer B: Lecithin cholesterol acyltransferase deficiency and fish eye disease. In: Valle DL, Antonarakis S, Ballabio A, Beaudet AL, Mitchell GA. eds. The Online Metabolic and Molecular Bases of Inherited Disease. McGraw-Hill; 2019. Accessed June 8, 2021. Available at https://ommbid.mhmedical.com/content.aspx?sectionid=225539713&bookid=2709
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.(Fujifilm Free Cholesterol E. Fujifilm Wako Pure Chemical Corporation; 04/01/2018)
Monday through Friday
This test was developed, and its performance characteristics 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.
84311
Test Id | Test Order Name | Order LOINC Value |
---|---|---|
CHLE | Cholesteryl Esters, S | 21197-9 |
Result Id | Test Result Name |
Result LOINC Value
Applies only to results expressed in units of measure originally reported by the performing laboratory. These values do not apply to results that are converted to other units of measure.
|
---|---|---|
CHLES | Cholesteryl Esters, S | 21197-9 |