Lp(a) in combination with other lipid tests can provide clinicians with much needed additional information on an individual's risk of developing cardiovascular disease.  It is of particular use in assessing the risk of coronary heart disease in specific populations as Lp(a) concentrations have been shown to be genetically determined and to vary with ethnic populations.   

Lp(a) is an LDL like particle with a molecule of Apolipoprotein B-100 (Apo B100) linked by a disulphide bridge to Apolipoprotein (a) (Apo(a)). Apo (a) is unique in that it is extremely heterogeneous in size. It is made up of a variable number of repeat structures known as kringles. The size heterogeneity of Apo (a) is due to the kringle 4 domain and the kringle 4 type 2 domain in particular which can be present in a variable number of repeat copies (3- 40).   

The use of Lp(a) as an independent risk factor for cardiovascular disease risk has been impeded by the lack of internationally accepted standardisation and the fact that many commercial Lp(a) methods suffer from apolipoprotein (a) size related bias.  The size heterogeneity of Apo (a) affects to varying degrees the outcome of many commercially available Lipoprotein (a) kits resulting in the underestimation of Apo (a) in samples containing an Apo (a) molecule smaller than that used in the assays calibrator and conversely to overestimate the concentration in samples containing larger Apo (a) particles. The antibody used in the Randox method detects the complete Lp(a) molecule providing accurate and consistent results.   

Research has documented and shown the Randox method to be one of only few to exhibit minimum size related bias.  The International Federation of Clinical Chemistry (IFCC) have conducted studies which clearly highlight the extent of the problem in other commercially available products and now recommend laboratories use tests from suppliers who do not suffer from Apo (a) size related bias.  

Not only is the Randox Lp(a) kit robust against Apo (a) size heterogeneity it is also standardised to the WHO/IFCC reference material SRM 2B and is closest in terms of agreement to the ELISA reference method.  Other benefits of the Randox Lp(a) kit include:  

• Liquid ready to use reagents
• Excellent stability - open vial stability of 30 days on board the analyser at 10^oC
• Dynamic assay range 3 - 90 mg/dl
• Excellent precision - within run CVs <3%
• No sample preparation required
• Limited interference from Intralipid^®, Bilirubin, Haemoglobin, Ascorbic Acid, Triglycerides, Plasminogen and Apolipoprotein B
• Dedicated or multi-analyte controls and calibrators available
• Fully automated applications available for a wide range of clinical analysers 

For further information please visit www.randox.com