Vitamin D – challenges in diagnosing and monitoring of hypovitaminosis D / Vitamin D – izazovi u dijagnozi i praćenju hipovitaminoze D
Summary During recent years, it has been recognized that sub-optimum vitamin D-status, often defined as decrease of PTH concentrations in response to supplementation of vitamin D, is a very widespread finding with potential health effects on a population level. As a consequence, there is a con tinuously increasing interest in the laboratory-based asses sment of the vitamin D status, with 25-hydroxyvitamin D as the most widely used analyte. However, there is a number of challenges in the characterization of the individual vitamin D status that are addressed in this article; they in clu - de analytical issues of 25-hydroxyvitamin D measurement; interpretation of results; development of guidelines for ratio - nal indication for laboratory testing; and evaluation of the role of 25-hydroxyvitamin D in the context of complementary markers of the vitamin D status.