25-OH-vitamin D assay variation and subject management in clinical practice.
OBJECTIVE
To compare two methods for assessing vitamin D status in clinical settings.


METHODS
25-OH-vitamin D status was measured in 120 patients by HPLC and a commercial immunoassay.


RESULTS
Only 53% of the subjects considered as vitamin D sufficient by immunoassay fell within this category according to HPLC although subjects with concentrations above 75 nmol/L, regardless of the method used, presented normal PTH concentrations.


CONCLUSIONS
Both methods are not exchangeable to classify subjects based on unique cut-offs but they are comparable when interpreted in relation with PTH concentrations.
Granado-Lorencio
F
F
Unidad de Vitaminas, Servicio de Bioquímica Clínica, Hospital Universitario Puerta de Hierro-Majadahonda, 28222, Madrid, Spain. fgranado.hpth@salud.madrid.org
Mosteiro
J Salazar
JS
Herrero-Barbudo
C
C
Navarro
E Donoso
ED
Blanco-Navarro
I
I
Pérez-Sacristán
B
B
D002851:Chromatography, High Pressure Liquid; D006801:Humans; D007118:Immunoassay / Q000379:methods*; D008875:Middle Aged; D010281:Parathyroid Hormone / Q000097:blood; D012372:ROC Curve; D014807:Vitamin D / Q000097:blood*
D010281:Parathyroid Hormone; D014807:Vitamin D