News from the Canadian scene
News from the Canadian scene
Contributed by Edgard Delvin, IFCC eNewletter Editor
The CSCC Vitamin D Working Group: purpose and objectives
Vitamin D supplements are highly publicized as being beneficial not only for bone health but also for a wide array of conditions including cancer and diabetes. This has caused an ever-increasing demand for vitamin D measurements that have reached untenable levels for most clinical laboratories in terms of staffing and funding.
Calcidiol (25OHD), produced in the liver, adequately reflects the vitamin D status insofar as enterohepatic cycle and absorption processes are normal. As calcitriol [1,25(OH)2D] production is tightly controlled by the kidney, circulating concentrations do not, under normal circumstances, increase in response to increased vitamin D intake or sun exposure..
Questions at hand are the clinical pertinence of the requests and the clinical utility of the results since, the turn-around time for reporting 25OHD and 1,25(OH)2D values exceeds 2 to 3 weeks in some areas of the country. Furthermore, most clinical laboratories are using immunoassays with varying analytical performance, leading to potential misclassification of patients.
Hanley et al. (1) have recently published an excellent systematic review on vitamin D and osteoporosis in which these topics are mentioned.
The Canadian Society of Clinical Chemists (CSCC) has therefore created a Working Group (VitD WG) to propose a set of guidelines addressing clinical indications and frequency of 25OHD and 1,25(OH)2D measurements.
The founding members of the VitD WG are: Drs. Edgard Delvin (Coordinator), Khosrow Adeli, Ed Randell, Pete Kavsak, Ted Dunn, Denis Lehotay, Yu Chen, Paul Yip, Sheila Boss, Lufang Yang, Isolde Seiden Long, Laurel Thoralcius, Curtis Oleschuck and Mary-Ann Sanfaçon. Two industry representatives are included: Scott Gillingwater and John Vukovic (Waters Corporation)
- Hanley DA, Cranney A, Jones G, Whiting SJ, Leslie WD, Cole DEC et al.
Vitamin D in adult health and disease: a review and guideline statement from Osteoporosis Canada.
CMAJ 2010; DOI:10.1503/cmaj.080663.