PERFORMANCE OF A DIRECT LDL-CHOLESTEROL METHOD COMPARED TO BETA-QUANTIFICATION

Low-density lipoprotein cholesterol is currently estimated by clinical laboratories using the Friedewald formula which requires fasting spec imens and is subject to error with increasing triglyceride levels. We describe a rapid method for isolating low-density lipoproteins by immu noseparation for subsequent measurement of cholesterol by enzymatic as say. The Direct LDL(TM) Immunoseparation Reagent meets current guideli nes for precision with intra-assay and interassay coefficients of vari ation of <3%. The results are highly correlated to the beta quantifica tion reference method (r=0.980). The results are generally not affecte d by increasing levels of triglycerides or high-density lipoprotein ch olesterol and patient fasting is not required for accurate analysis. T he Direct LDL Immunoseparation Reagent overcomes limitations of the Fr iedewald formula and appears to be suitable for accurate quantitation of low-density lipoprotein cholesterol in the routine laboratory.