Synonyms
- Oxidized LDL
- OxLDL
Expected Turnaround Time
3 - 5 days
Turnaround time is defined as the usual number of days from the date of pickup of a specimen for testing to when the result is released to the ordering provider. In some cases, additional time should be allowed for additional confirmatory or additional reflex tests. Testing schedules may vary.
Related Documents
Specimen Requirements
Specimen
Plasma (preferred) or serum (acceptable)
Volume
0.5 mL
Minimum Volume
0.2 mL
Container
Lavender-top (EDTA) tube (preferred) or gel-barrier tube
Collection
For plasma, draw blood into an EDTA tube and gently invert the tube 8 to 10 times to mix the anticoagulant. Centrifuge the tube, remove the stopper and draw off approximately 2/3 of the upper plasma layer into a labeled transport tube using a transfer pipet bulb. Note: This ensures the buffy coat of white cells and red cells remain undisturbed. Plasma must be separated from cells within 45 minutes of venipuncture. Send plasma in a frozen plastic transport tube.
To avoid delays in turnaround time when requesting multiple tests on frozen samples, please submit separate frozen specimens on each test requested.
Storage Instructions
Freeze.
Stability Requirements
Temperature | Period |
|---|---|
Room temperature | Unacceptable (stability provided by manufacturer or literature reference) |
Refrigerated | Unacceptable (stability provided by manufacturer or literature reference) |
Frozen | 2 years (stability provided by manufacturer or literature reference) |
Freeze/thaw cycles | Stable x1 (stability provided by manufacturer or literature reference) |
Patient Preparation
Overnight fasting is preferred.
Causes for Rejection
Specimen other than EDTA plasma or serum; improper labeling; specimen not stored properly; specimen older than stability limits; hemolysis; lipemia; non-frozen sample received
Test Details
Use
For the in vitro quantitative measurement of oxidized low density lipoproteins (oxidized LDL) in human serum or plasma.
Measurement of oxidized LDL (oxLDL) has been incorporated into clinical practice in the diagnosis and treatment of lipid disorders (such as diabetes mellitus), atherosclerosis, and various liver and renal diseases, especially as it pertains to the evaluation of oxidative stress. Oxidized LDL-particles are considered to be an important driving factor in the pathophysiology of atherosclerosis and oxLDL measurement has been used to test the efficacy of CVD drugs (eg, statins) to reduce oxidative stress.9
Limitations
Lipemic or hemolytic samples may give erroneous results and should not be used for analysis.
Methodology
Enzyme-linked immunoassay (ELISA)
Reference Interval
10–170 ng/mL
Additional Information
The oxidative conversion of low density lipoproteins (LDL) to oxidized low density lipoproteins (oxidized LDL) is now considered to be a key event in the biological process that initiates and accelerates the development of the early atherosclerotic lesion, the fatty streak.1-5
Experimental studies have shown that native LDL becomes atherogenic when it is converted to oxidized LDL, and that oxidized LDL is more atherogenic than native LDL.1-5 Oxidized LDL is found in monocyte-derived macrophages in atherosclerotic lesions, but not in normal arteries.6 The uptake of LDL into macrophages does not occur by way of the classic Brown/Goldstein LDL receptor.7 Numerous studies1-5,8 have established that LDL, the major carrier of blood cholesterol, must first be converted to oxidized LDL so that it can be recognized by "scavenger" or "oxidized LDL receptors" on monocyte-derived macrophages. The binding of oxidized LDL to macrophages is a necessary step by which oxidized LDL induces cholesterol accumulation in macrophages, thus transforming the macrophages into lipid-laden foam cells.8
Footnotes
1. Steinberg D. Low density lipoprotein oxidation and its pathobiological significance. J Biol Chem. 1997 Aug 22; 272(34):20963-20966.9261091
2. Berliner JA, Navab M, Fogelman AM, et al. Atherosclerosis: basic mechanisms. Oxidation, inflammation, and genetics. Circulation. 1995 May 1; 91(9):2488-2496.7729036
3. Steinberg D. Lewis A. Conner Memorial Lecture. Oxidative modification of LDL and atherogenesis. Circulation. 1997 Feb 18;95(4):1062-1071.9054771
4. Heinecke JW. Oxidants and antioxidants in the pathogenesis of atherosclerosis: implications for the oxidized low density lipoprotein hypothesis. Atherosclerosis. 1998 Nov;141(1):1-15.9863534
5. Witztum JL, Hörkkö S. The role of oxidized LDL in atherogenesis: immunological response and anti-phospholipid antibodies. Ann N Y Acad Sci. 1997 Apr 15;811:88-96; discussion 96-99.9186588
6. Ylä-Herttuala S. Is oxidized low-density lipoprotein present in vivo? Curr Opin Lipidol. 1998 Aug;9(4):337-344.9739490
7. Brown MS, Goldstein JL. Lipoprotein metabolism in the macrophage: implications for cholesterol deposition in atherosclerosis. Annu Rev Biochem. 1983;52:223-261.6311077
8. Chisolm GM 3rd, Hazen SL, Fox PL, Cathcart MK. The oxidation of lipoproteins by monocytes-macrophages. Biochemical and biological mechanisms. J Biol Chem. 1999 Sep 10;274(37):25959-25962.10473535
9. Pfützner A A, Efstrathios K, Löbig M, Armbruster FP, Hanefeld M, Forst T. Differences in the results and interpretation of oxidized LDL Cholesterol by two ELISA assays--an evaluation with samples from the PIOstat Study. Clin Lab. 2009;55(7-8):275-281.19894406
LOINC® Map
| Order Code | Order Code Name | Order Loinc | Result Code | Result Code Name | UofM | Result LOINC |
|---|---|---|---|---|---|---|
| 123023 | Oxidized LDL | 90364-1 | 123024 | Oxidized LDL | ng/mL | 90364-1 |
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