2016, Cilt 14, Sayı 3, Sayfa(lar) 181-188 |
|
Analytical Performance of Immuno Assay Method of 25 Hydroxy Vitamin D |
Pelin Kulan1, Ahmet Rıza Uras2, Sedef Delibaş3, Mustafa Durmuşcan4, Sembol Yıldırmak5 |
1SB 1 nolu Halk Sağlığı Laboratuvarı, Tıbbi Biyokimya, İstanbul, Türkiye 2Haydarpaşa Numune Eğitim ve Araştırma Hastanesi, Tıbbi Biyokimya, İstanbul, Türkiye 3Mağusa Tıp Merkezi Hastanesi, Tıbbi Biyokimya, Magusa, Kuzey Kıbrıs TC 4Adana Halk Sağlığı Laboratuvarı, Tıbbi Biyokimya, Adana, Türkiye 5Giresun Üniversitesi Tıp Fakültesi, Tıbbi Biyokimya, Giresun, Türkiye |
Keywords: 25-hydroxy vitamin D, Analytical performance, Immuno assay, High performance liquid chromatography |
Aim: Method evaluation studies should be carried out for every new method planned to be used in
laboratories. The aim of this study is to determine the analytical performance of the immunoassay
method used for determining of plasma 25-hydroxy vitamin D levels and also to compare to high
performance liquid chromatography (HPLC) method.
Materials and Methods: 113 plasma samples were used to carry out repeatability, linearity and
recovery studies for 25-hydroxy vitamin D measurement with the Abbott Architect chemiluminescence
immunoassay (CLIA) method. HPLC was accepted as reference method. Method comparison study was
carried out.
Results: The coefficient of variations for the Architect 25-hydroxy vitamin D method were 4.07% and
2.42 % within-day; 4.77% and 3.93% between-day for low and intermediate plasma levels respectively.
The results obtained from the recovery studies were 92.5% and 105.9% for low levels; and 108.3% and
105.5% for intermediate levels. As a result of the method comparison study, Architect method was
found to have a significant negative bias [As mean, 9 ng/mL lower, ±2SD interval: (-34.1) – (16.1)
ng/mL] and it was also observed that there was a constant and proportional difference between that two
methods (HPLC= -3.2657 + 1.7388 CLIA; rho= 0.656).
Conclusion: Architect 25-hydroxy vitamin D method has met the precision, linearity and recovary
targets but not the bias targets. For the accurate diagnosis and treatment follow-up of Vitamin D
deficiency, it is obvious that to carry out analytical performance studies and to standardize of the
measurement methods are essential. As the use of standard reference materials developed for the
standardization of vitamin methods becomes widespread, the inter-method variability will also
decrease. In addition, participation in laboratories' external quality assessment programs and their
assessment of results will provide significant contributions to the use of laboratory findings for patient
benefit.
|
|
|