Review article

https://doi.org/10.11613/BM.2020.020501

In sickness and in health: pivotal role of vitamin D

Nora Nikolac Gabaj orcid.org/0000-0001-6831-6309 ; Department of Clinical Chemistry, Sestre milosrdnice University Hospital Center, Zagreb, Croatia; Faculty of Pharmacy and Biochemistry, University of Zagreb, Zagreb, Croatia
Adriana Unic orcid.org/0000-0003-2175-5851 ; Department of Clinical Chemistry, Sestre milosrdnice University Hospital Center, Zagreb, Croatia
Marijana Miler orcid.org/0000-0002-0569-924X ; Department of Clinical Chemistry, Sestre milosrdnice University Hospital Center, Zagreb, Croatia
Tomislav Pavicic orcid.org/0000-0003-1914-7056 ; Department of Clinical Chemistry, Sestre milosrdnice University Hospital Center, Zagreb, Croatia
Jelena Culej ; Department of Clinical Chemistry, Sestre milosrdnice University Hospital Center, Zagreb, Croatia
Ivan Bolanca ; Department of Human Reproduction, Sestre milosrdnice University Hospital Center, Zagreb, Croatia
Davorka Herman Mahecic ; Department for Endocrinology, Dieabetes and Metabolism, Sestre milosrdnice University Hospital Center, Zagreb, Croatia
Lara Milevoj Kopcinovic orcid.org/0000-0003-0360-9148 ; Department of Clinical Chemistry, Sestre milosrdnice University Hospital Center, Zagreb, Croatia
Alen Vrtaric ; Department of Clinical Chemistry, Sestre milosrdnice University Hospital Center, Zagreb, Croatia

Abstract

Within the last several years, frequency of vitamin D testing has multiplied substantially all over the world, since it has been shown to have an important role in many diseases and conditions. Even though liquid chromatography - tandem mass spectrometry (LC-MS/MS) has been identified as “gold standard” method for vitamin D measurement, most laboratories still use immunochemistry methods. Besides analytical problems (hydrophobicity, low circulating concentrations, ability to bind to lipids, albumins and vitamin D binding protein, presence of multiple vitamin D metabolites and variable ratios of 25(OH)D2 and 25(OH)D3 in the blood), vitamin D shows great preanalytical variability, since its concentration is drastically
influenced by seasonal changes, exposure to sun, type of clothes or sun block creams. Vitamin D is mostly measured in serum or plasma, but new studies are showing importance of measuring vitamin D in pleural effusions, breast milk, urine, synovial fluid and saliva. Besides the main role in calcium homeostasis and bone metabolism, many studies linked vitamin D deficiency with cancer, cardiovascular diseases, diabetes, fertility and many other conditions. However, even though initial observational studies indicated that supplementation with vitamin D might be beneficial in disease development and progression; first results of well-designed randomized controlled prospective studies did not find differences in frequency of cardiovascular
events or invasive cancer between patients taking vitamin D supplementation compared to placebo. In the light of these recent findings, validity of excessive vitamin D testing remains an open question.

Keywords

vitamin D; preanalytical variability; diabetes mellitus; polymorphism; fertility; extravascular body fluids

Hrčak ID:

238902

URI

https://hrcak.srce.hr/238902

Publication date:

15.6.2020.

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