Reference standardization and triglyceride interference of a new homogeneous HDL-cholesterol assay compared with a former chemical precipitation assay.
A homogeneous HDL-c assay (HDL-H), which uses polyethylene glycol-modified enzymes and sulfated alpha-cyclodextrin, was assessed for precision, accuracy, and cholesterol and triglyceride interference. In addition, its analytical performance was compared with that of a phosphotungstic acid (PTA)/MgCl2 precipitation method (HDL-P). Within-run CVs were < or = 1.87%; total CVs were < or = 3.08%. Accuracy was evaluated in fresh normotriglyceridemic sera using the Designated Comparison Method (HDL-H = 1.037 Designated Comparison Method + 4 mg/L; n = 63) and in moderately hypertriglyceridemic sera by using the Reference Method (HDL-H = 1.068 Reference Method - 17 mg/L; n = 41). Mean biases were 4.5% and 2.2%, respectively. In hypertriglyceridemic sera (n = 85), HDL-H concentrations were increasingly positively biased with increasing triglyceride concentrations. The method comparison between HDL-H and HDL-P yielded the following equation: HDL-H = 1.037 HDL-P + 15 mg/L; n = 478. We conclude that HDL-H amply meets the 1998 NCEP recommendations for total error; its precision is superior compared with that of HDL-P, and its average bias remains below +/-5% as long as triglyceride concentrations are < or = 10 g/L and in case of moderate hypercholesterolemia.
Cobbaert
C
C
Academic Hospital Rotterdam, The Netherlands. boersma@ckcl.azr.nl
Zwang
L
L
Ceriotti
F
F
Modenese
A
A
Cremer
P
P
Herrmann
W
W
Hoss
G
G
Jarausch
J
J
Türk
R
R
März
W
W
Nauck
M
M
D011232:Chemical Precipitation; D002784:Cholesterol / Q000097:blood; D002789:Cholesterol Oxidase; D008076:Cholesterol, HDL / Q000097:blood*; D003505:Cyclodextrins; D006801:Humans; D006949:Hyperlipidemias / Q000097:blood; D015636:Magnesium Chloride; D010772:Phosphotungstic Acid; D011092:Polyethylene Glycols; D012015:Reference Standards; D012044:Regression Analysis; D002787:Sterol Esterase; D014280:Triglycerides / Q000097:blood*; D014461:Ultracentrifugation
D008076:Cholesterol, HDL; D003505:Cyclodextrins; D014280:Triglycerides; D015636:Magnesium Chloride; D010772:Phosphotungstic Acid; D011092:Polyethylene Glycols; D002784:Cholesterol; D002789:Cholesterol Oxidase; D002787:Sterol Esterase