Vitamin D deficiency is the cause of rickets in children, and osteomalacia in adults. It may also predispose to various diseases including cardiovascular, neoplastic, infectious, metabolic, and autoimmune diseases
Vitamin D in CKD Patients
Althoughvitamin D defciency is pandemic, the prevalence and severity of vitamin D defciency is much more evident among CKD patients as disclosed in all epidemiologic studies. Serum level of 25 OH D is the most appropriate diagnostic test for vitamin D status [8]. Serum level above 30 ng/mL (75 nmol/L) is considered sufcient, while a level between 20 and 30 ng/mL (50-75 nmol/L) is considered as vitamin D insufciency and level below 20 ng/mL (50 nmol/L) denotes vitamin D defciency [8]. Vitamin D defciency is the cause of rickets in children, and osteomalacia in adults. It may also predispose to various diseases including cardiovascular, neoplastic, infectious, metabolic, and autoimmune diseases. Vitamin D defciency accelerates the progression of CKD. Vitamin D defciency results in activation of the renin angiotensin system, transforming growth factor within the kidney, decreased nephrin and podocin within the glomerular basement membrane, and increased renal fbrosis [9,10]. Different factors are incriminated as causes of vitamin D defciency among CKD patients. These factors include environmental and culture factors, dietary restriction, diabetes and increased body mass index [11]. UAE is also accused in as another cause of vit D defciency [12]. While some studies reported signifcant association with age, other studies failed to show similar association. Similar discrepancies are observed regarding association with body weight, and diabetic status. According to KDIGO guidelines issued this month, patients with CKD G3a– G5D, should have 25OHD levels measured repeatedly, and vitamin D defciency and insufciency to be corrected using treatment strategies recommended for the general population. 1. Webb AR, Kline L, Holick MF. Influence of season and latitude on the cutaneous synthesis of vitamin D3: exposure to winter sunlight in Boston and Edmonton will not promote vitamin D3 synthesis in human skin. J Clin Endocrinol Metab. 1988 Aug;67(2):373-8. 2. Bikle DD: Vitamin D metabolism, mechanism of action, and clinical applications. Chem Biol. 2014 Mar 20;21(3):319-29. 3. Tripkovic L1, Lambert H, Hart K, Smith CP, Bucca G, Penson S, et al., Comparison of vitamin D2 and vitamin D3 supplementation in raising serum 25-hydroxyvitamin D status: a systematic review and meta-analysis. Am J Clin Nutr. 2012 Jun;95(6):1357-64. 4. Hollis BW. Comparison of equilibrium and disequilibrium assay conditions for ergocalciferol, cholecalciferol and their major metabolites. J Steroid Biochem. 1984 Jul;21(1):81-6. 5. Imawari M, Kida K, Goodman DS. The transport of vitamin D and its 25-hydroxy metabolite in human plasma. Isolation and partial characteri-zation of vitamin D and 25-hydroxyvitamin D binding protein. J Clin Invest.1976 Aug;58(2):514-23. 6. Fukagawa M, Komaba H, Hamano T. Vitamin D supplementation in renal disease: is calcitriol all that is needed? Scand J Clin Lab Invest Suppl. 2012;243:120-3. 7. Barragry JM, France MW, Carter ND, Auton JA, Beer M, Boucher BJ, et al., Vitamin-D metabolism in nephrotic syndrome. Lancet. 1977 Sep 24;2(8039):629-32. 8. Kennel KA, Drake MT, Hurley DL. Vitamin D defciency in adults: when to test and how to treat. Mayo Clin Proc. 2010 Aug;85(8):752-7 9. Plum L. A., Deluca H. F. Vitamin D, disease and therapeutic opportunities. Nature Reviews Drug Discovery. 2010;9(12):941–955. 10. DeLuca HF. Overview of general physiologic features and functions of vitamin D. Am J Clin Nutr.2004;80:1689S-1696S 11. Echida Y, Mochizuki T, Uchida K, Tsuchiya K, Nitta K. Risk factors for vitamin D defciency in patients with chronic kidney disease. Intern Med. 2012;51(8):845-50. 12. Caravaca-Fontán F, Gonzales-Candia B, Luna E, Caravaca F. Relative importance of the determinants of serum levels of 25-hydroxy vitamin D in patients with chronic kidney disease. 12. Nefrologia. 2016 Sep - Oct;36(5):510-516. References: Vitamin D defciency is the cause of rickets in children, and osteomalacia in adults. It may also predispose to various diseases including cardiovascular, neoplastic, infectious, metabolic, and autoimmune diseases Different factors are incriminated as causes of vitamin D deficiency among CKD patients. These factors include environmental and culture factors, dietary restriction, diabetes and increased body mass index