Overestimation of the 25(OH)D serum concentration with the automated IDS EIA kit.
We have recently observed an increasing number of patients presenting very high serum levels of 25-hydroxyvitamin D [25(OH)D] (> 150 ng/mL), which, in all cases, had been measured with the IDS EIA kit adapted on different "open" automated platforms. We performed a comparison between the IDS EIA kit adapted on two different "open"automated platforms and the DiaSorin RIA. We found a systematic bias (higher levels with the IDS EIA kit) for concentrations more than 50-60 ng/mL that was less obvious when the IDS EIA was used in its manual procedure. We thus suggest to use the IDS EIA kit in its manual procedure rather than to adapt it on an automated platform, and to interpret cautiously a 25(OH)D greater than 100 ng/mL with this kit.
Cavalier
Etienne
E
Department of Clinical Chemistry, University Hospital of Liege, University of Liege, Liege, Belgium. etienne.cavalier@chu.ulg.ac.be
Huberty
Véronique
V
Cormier
Catherine
C
Souberbielle
Jean-Claude
JC
D001331:Automation; D001774:Blood Chemical Analysis / Q000295:instrumentation* / Q000379:methods*; D002624:Chemistry, Clinical / Q000379:methods; D006801:Humans; D007124:Immunoenzyme Techniques / Q000379:methods*; D015203:Reproducibility of Results; D053719:Tandem Mass Spectrometry / Q000379:methods; D014807:Vitamin D / Q000031:analogs & derivatives* / Q000097:blood / Q000378:metabolism
D014807:Vitamin D; C104450:25-hydroxyvitamin D