sdLDL-Cholesterol assay

Description

Intended Use

The sdLDL-C test is for the quantitative determination of small, dense (sd) LDL cholesterol (-C) in human serum or plasma. The sdLDL-C test is used in conjunction with other lipid measurements and clinical evaluations to aid in the risk management of lipoprotein disorders associated with cardiovascular disease.

Clinical Significance

Elevated low-density lipoprotein (LDL) cholesterol (-C) in blood has long been regarded as a risk factor for coronary heart disease (CHD). Recently, LDL-C sub-fractions (subclasses) have emerged to further elucidate the association between lipid levels and development of CHD. Small, dense LDL cholesterol (sdLDL-C) is one of such sub-fractions marked by smaller particle size and higher density. sdLDL is an atherogenic lipoprotein due to their higher retention into the arterial wall, their lower binding affinity for the LDL receptor, their prolonged plasma half-life and their lower resistance to oxidative stress compared to that of large buoyant LDL cholesterol (lbLDL-C). Various epidemiological and pathological studies have demonstrated the relationship between sdLDL-C level and CHD. To date, ultracentrifugation and electrophoresis-based methods are used for the measurement of sdLDL-C but these methods are both laborious and time-consuming. The sdLDL-C test is a direct method for the quantitative determination of sdLDL-C, using automated chemistry analyzers capable of accommodating two-reagent assays. The test is completed within 10 minutes.