EVALUATION OF A RAPID HOMOGENEOUS METHOD FOR DIRECT MEASUREMENT OF HIGH-DENSITY-LIPOPROTEIN CHOLESTEROL

We evaluated the performance of a direct Liquid N-geneous HDL-C assay (N-HDL; Genzyme Diagnostics, Cambridge, Mass) and compared it with a C enters for Disease Control and Prevention (CDC) modified reference pro cedure (M-REF) and phosphotungstic acid (PTA) precipitation method in patients with normotriglyceridemia (triglyceride level, <400 mg/dL) an d hypertriglyceridemia (triglyceride level, greater than or equal to 4 00 mg/dL). Excellent intra-assay and interassay coefficients of variat ion were obtained (<2.0%) using the N-HDL method exhibited better corr elation with M-REF than the PTA assay. In addition, compared with M-RE F, the mean absolute percentage bias of N-HDL was lower than the PTA a ssay in normotriglyceridemic (4.9% vs 5.8%) and hypertriglyceridemic ( 5.4% vs 12.9%) samples. Hemolysis, ascorbic acid, and bilirubin did no t interfere with the N-HDL assay. On the basis of these findings, the N-HDL assay compares favorably with the modified CDC reference method and seems superior the PTA assay. It also has the advantage of being s uited for complete automation and, thus, would prove useful in large c linical laboratories.