ERRATA

This article refers to:

Approaches to measurement of Vitamin D concentrations - Immunoassays

In the article“Approaches to measurement of Vitamin D concentrations – Immunoassays“, by Dr Beatus Ofenloch-Haehnle, published in Supplement 243 of the current volume of Scandinavian Journal of Clinical and Laboratory Investigation (72(S343): S50-53, DOI 10.3109/00365513.2012.681955), two tables were not published. In addition, one of the tables was misplaced in “Vitamin D – why does it matter? – Defining Vitamin D deficiency and its prevalence“ by Prof Heike A. Bischoff-Ferrari on pages S3-6, DOI 10.3109/00365513.2012.681938, and another omitted from the submitted manuscript.

Table I and II in Dr Beatus Ofenloch-Haehnle‘s article are missing and reproduced below:

Table I. Design of Immunoassays.

Immunoassay	Specifier	Detetction technology	Pretreatment reagent
Diasorin 25-Hydroxyvitamin D ^125I RIA Kit (Package Insert 2010)	Polyclonal goat antibody	Radio immunoassay (Iodine-125)	Acetonitrile precipitation
IDS 25-hydroxyvitamin D RIA Ref [12]	Polyclonal sheep antibody	Radio immunoassay (Iodine-125)	Acetonitrile precipitation
LIAISON® 25 OH D TOTAL (Package Insert 2010)	Polyclonal goat antibody [1]	Chemiluminescence (Luminol)	15 % ethanol, surfactants, 0.2 % ProClin300
ADVIA Centaur® Vitamin D total (Package Insert 2011)	monoclonal mouse antibody	Chemiluminescence (Acridinium Ester)	Not disclosed
ARCHITECT 25-OH Vitamin D (Package Insert 2011)	polyclonal sheep antibody	Chemiluminescence (Acridinium Ester)	Reagent 1 and 2: triethanolamine methanol buffer and 8-anilino-1-naphtalensulfonic acid (ANSA).
IDS-iSYS 25-Hydroxy Vitamin D (Package Insert 2011)	polyclonal sheep antibody	Chemiluminescence (Acridinium Ester)	Reagent 1: sodium hydroxide Reagent 2: assay buffer containing proprietary displacing compounds, methanol (10 % to 20 %) and sodium azide
Elecsys® Vitamin D total (Package insert 2011)	recombinant human vitamin D binding protein	Electrochemi-luminescence	Reagent 1: dithiothreitol Reagent 2 sodium hydroxide

Table II. Reference Calibration and Traceability of Immunoassays.

Immunoassay	Reference Calibration	Measuring Interval (nmol/L)
LIAISON® 25 OH D TOTAL (Package Insert 2010)	Diasorin 25-Hydroxyvitamin D ^125I RIA Kit (initially standardized by UV quantification)	12.5–375
ADVIA Centaur® Vitamin D total (Package Insert 2011)	Internal standards traceable to LC-tandem-MS	9.25–375
ARCHITECT 25-OH Vitamin D (Package Insert 2011)	Standardized against LC-tandem MS	20–400
IDS-iSYS 25-Hydroxy Vitamin D (Package Insert 2011)	UV quantification verified by LC-tandem MS	12.5–350
Elecsys® Vitamin D total (Package insert 2011)	Standardized against LC-tandem MS. LC tandem MS verified by NIST standard	7.5–175

Prof Stefan Pilz wants to make the following corrections and clarifications to the “Questions and Answers” following his article “Vitamin D and cardiovascular disease: update and outlook” (72(S343): S83-91, DOI 10.3109/00365513.2012.681972):

S Pilz answering M Kaelin (Switzerland)

I hope that on-going trials will provide definite answers, but these trials have some limitations have severe limitations. These include that study participants are included irrespective of their serum 25(OH)D concentration. Quite a significant vitamin D intake is permitted so that may be a problem.

S Pilz answering M Fukagawa

Yes, but for CKD I agree with what has been said by R Vieth; that we should consider the 25(OH)D concentration. If it is normal, we should think of prescribing active vitamin D. Sometimes there are difficulties in vitamin D deficient patients who are given additional 1,25(OH)₂D3. Another issue with CKD patients is that when you give calcitrol or other active vitamin D analogues, they may increase the degradation of 25(OH)D because of a reduction in the by 24 hydroxylases.

S Pilz answering P Rozentryt

You are referring to the paracalcitrol trial which studied renal patients and failed to show an effect on cardiac function. The issue is, was this the right therapy? It may be that the cardiomyocytes need more than then 25(OH)D. If just a small amount of 25(OH)D is intracellularly converted to the active form then a much higher local concentration can be achieved by vitamin D than with systemic therapy with 1,25(OH)₂D3 which may be harmful (e.g. due to hypercalcemia) or have and has a very narrow therapeutic window.