Comparison of a direct enzymatic assay and polyacrylamide tube gel electrophoresis for measurement of small,dense low-density lipoprotein cholesterol

Vanavanan S, Srisawasdi P, Rochanawutanon M, et al.

Clin Chem Lab Med 2015; 53: 139–148.

Increased small, dense low-density lipoprotein cholesterol (sdLDL-C) levels associate with increased risk of cardiovascular and cerebrovascular disease. However, currently available methods for its assessment including ultracentrifugation, electrophoresis techniques, and nuclear magnetic resonance are expensive, time-consuming, and technically demanding, thus limiting their routine application.

Here, the authors compare a direct enzymatic method adapted on an automated system and a polyacrylamide tube gel electrophoresis (PGE) assay for determination of sdLDL-C. The two sdLDL-C assays were strongly correlated. However, the enzymatic assay for sdLDL-C showed markedly higher sdLDL-C concentrations than polyacrylamide tube gel electrophoresis (0.86 ± 0.33 vs. 0.24 ± 0.32 mmol/L). Of note, this bias was not concentration-dependent. Rather, the enzymatic assay measured a broader range of atherogenic lipoprotein particles. The enzymatic method can be adapted for automated laboratory testing and may be effective in assessing vascular risk in clinical practice.

With the study results in mind, it would be premature to make speculative conclusions as well as rosy visions of future developments. However, the article helps putting routine sdLDL-C assessment within reach.