Vitamin D deficiency and parathyroid hormone levels following renal transplantation in children

Children's National Medical Center, Washington, DC, USA.
Pediatric Nephrology (Impact Factor: 2.86). 12/2010; 25(12):2509-16. DOI: 10.1007/s00467-010-1612-0
Source: PubMed


The objectives were to determine the prevalence of vitamin D deficiency [25(OH)D < 10 ng/ml] in pediatric renal transplant (RTx) recipients, compared with controls and identify correlates of changes in 25(OH)D and intact parathyroid hormone (iPTH) levels following transplantation. Serum 25(OH)D, 1,25(OH)(2)D, and iPTH were measured once in 275 healthy controls and at transplantation, and 3 and 12 months posttransplantation in 58 RTx recipients. Multivariate logistic regression models determined the odds ratio (OR) of vitamin D deficiency in RTx recipients vs. controls adjusted for age, sex, race, and season. Generalized estimating equations were used to assess changes following transplantation. At transplantation, 22% of nonblack and 27% of black RTx recipients were vitamin D deficient. The adjusted OR of vitamin D deficiency was greater in RTx recipients (p < 0.001) compared with controls; however, the transplant association was greater in nonblack vs. black individuals (interaction p = 0.02). Overall, 25(OH)D levels did not change significantly following transplantation. Younger age (p < 0.01), nonblack race (p < 0.001), visits in nonwinter months (p < 0.001), and supplementation with ≥400 IU/day ergo/cholecalciferol (p < 0.001) were associated with increases (or lesser declines) in 25(OH)D following transplantation. Increases in 25(OH)D levels (p < 0.001) and vitamin D supplementation (p < 0.01) were associated with greater reductions in iPTH levels following transplantation, independent of 1,25(OH)(2)D levels.

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    • "In addition, deficiency of nutritional vitamin D contributes to decreased production of 1,25-(OH)2D3 and is also directly associated with more severe secondary hyperparathyroidism along the entire spectrum of CKD, both before and after kidney transplant. Even when there is little or no residual 1-alpha-hydroxylase activity in the late stages of CKD, nutritional vitamin D deficiency leads to more marked secondary hyperparathyroidism (12, 16). "
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