ABSTRACT
Nephelometry, which is considered as the reference method for serum proteins determination requires a specific equipment. The majority of protein determinations are therefore carried out on biochemistry automats using turbidimetry. The objective of a CNBH group (Collège national de biochimie des hôpitaux) was to compare nephelometry and turbidimetry for 7 automats: 2 nephelometers, the BN Prospec (Dade-Behring) and Immage (Beckman-Coulter) and 5 biochemistry systems using turbidimetry, the Integra and Modular (Roche Diagnostics), the LX20 (Beckman-Coulter), RXL (Dade-Behring) and AU (Olympus). The study was based on the determination of sera collections (albumin, ApoA, CRP, haptoglobin, IgM, transthyretin) of 140 samples each: 110 limpid samples and 30 samples called HLI (hemolytic, lipemic or icteric). Fifteen hospitals took part to this work. An ANOVA analysis on limpid samples and quality control sera concluded to an "automat" effect for the 6 tested proteins but did not show a "method" effect, (i.e. nephelometry versus turbidimetry). On the other hand, the transferability of the results was expected to be better and an effort on the choice of the antibodies and the standardization procedures should be made.
Subject(s)
Apolipoproteins A/analysis , C-Reactive Protein/analysis , Haptoglobins/analysis , Immunoglobulin M/analysis , Prealbumin/analysis , Serum Albumin/analysis , Humans , Nephelometry and Turbidimetry/methods , Reproducibility of Results , Sensitivity and SpecificityABSTRACT
Creatinine is the criterion the most widely used for kidney exploration, either directly or through algorithms. Up to now, it appears that methods of creatinine determination are still very heterogenous. The aim of the present study was to compare the different available methods and to evaluate their impact on the formula of predicted clearance. The study revealed that significant discrepancies can be observed depending on the methodology and analitycal principe. The results suggest that standardization of methods and comprehensive analysis of the different formula are necessary.