Mineral bone defects at esrd patients undergoing hemodialysis and its association with vitamin D receptor polymorphism

Chronic Renal Failure-Mineral bone Disorders occur at early stages of renal failure and continues in different forms during renal replacement therapy. Association studies related to the Calcium/PTH/Calcitriol axis indicate that genetic factors may be responsible for interindividual variability in the occurrence and severity of bone and mineral metabolism abnormalities among ESRD patients.Aim: We aimed that, to analyse the association of mineral bone defects at hemodialysis patients with Vitamin D receptor polymorphism and the effects of vitamin D receptor polymorphism on the comorbid diseases with these ESRD patients.Materials and Methods: 100 ESRD patients >18 years old undergoing hemodialysis for a three times a week for 3-5 hours and 50 voluntary, healty man and women with have no malignancy were as a control study determined. Demographic features like age, gender, weight and height, primary diseases causes ESRD and hemodilaysis durations were recorded.Comorbidities (HT, DM,PDH,KVH,HL), parathyroid adenomas, parathyroidectomy, and types of D vit used recorded. Electrolite (Na, K, ca, P) levels (average of the last 3 months), BUN, creatinin, albumin, ALP, PTH levels; avarage of the last 1 year, 25(OH)D levels recorded. Vitamin D FokI receptor polymorphism genotypings were studied.Results: VDR FokI polymorphism genotype frequencies in the patient population were %5.7(6) ff , %54.3 (57) FF, %39 (41) Ff and 68% FF, 32% Ff, 0.0% ff in a healthy control population. Vitamin D deficiency (<20 ng/ml ) was detected in 33 female patients (26,5%) and 21 male patients (27,5%). PTH levels were seperated three groups as <100, 100-450, >450 pg/ml. The patient group with PTH level >100 pg/ml has the most FF genotype(55).We compared 25(OH)D levels disribution with PTH levels disribution and detected that highest PTH levels were with 25(OH)D deficiency (<20 ng/ml) group. And also most of 25(OH) deficiency (<20 ng/ml) was with FF genotype(43).Conclusions: The occurrence of PTH levels (100 pg/ml) more in FF genotype suggest that FokI polymorphisms of the VDR gene may determine parathyroid response in CRF patients. However this hypoesis should be support wih well organized, large-scale studies.Keywords: Vit D FokI Receptor Polimorphism, Chronic renal failure, Calcium, Phosphorus,Vitamin D