Recovery of hyperphosphatoninism and renal phosphorus wasting one year after successful renal transplantation

Clin J Am Soc Nephrol. 2008 Nov;3(6):1829-36. doi: 10.2215/CJN.01310308. Epub 2008 Oct 15.

Abstract

Background and objectives: In the first months after successful kidney transplantation, hypophosphatemia and renal phosphorus wasting are common and related to inappropriately high parathyroid hormone (PTH) and fibroblast growth factor-23 (FGF-23) levels. Little is known about the long-term natural history of renal phosphorus homeostasis in renal transplant recipients.

Design, setting, participants: We prospectively followed parameters of mineral metabolism (including full-length PTH and FGF-23) in 50 renal transplant recipients at the time of transplantation (Tx), at month 3 (M3) and at month 12 (M12). Transplant recipients were (1:1) matched for estimated GFR with chronic kidney disease (CKD) patients.

Results: FGF-23 levels (Tx: 2816 [641 to 10665] versus M3: 73 [43 to 111] versus M12: 56 [34 to 78] ng/L, median [interquartile range]) and fractional phosphorus excretion (FE(phos); M3: 45 +/- 19% versus M12: 37 +/- 13%) significantly declined over time after renal transplantation. Levels 1 yr after transplantation were similar to those in CKD patients (FGF-23: 47 [34 to 77] ng/L; FE(phos) 35 +/- 16%). Calcium (9.1 +/- 0.5 versus 8.9 +/- 0.3 mg/dl) and PTH (27.2 [17.0 to 46.0] versus 17.5 [11.7 to 24.4] ng/L) levels were significantly higher, whereas phosphorus (3.0 +/- 0.6 versus 3.3 +/- 0.6 mg/dl) levels were significantly lower 1 yr after renal transplantation as compared with CKD patients.

Conclusions: Data indicate that hyperphosphatoninism and renal phosphorus wasting regress by 1 yr after successful renal transplantation.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Calcitriol / blood
  • Case-Control Studies
  • Chronic Disease
  • Female
  • Fibroblast Growth Factors / blood
  • Glomerular Filtration Rate
  • Humans
  • Hypophosphatemia / etiology*
  • Hypophosphatemia / metabolism
  • Hypophosphatemia / physiopathology
  • Kidney / metabolism*
  • Kidney / physiopathology
  • Kidney Diseases / metabolism
  • Kidney Diseases / physiopathology
  • Kidney Diseases / surgery*
  • Kidney Transplantation / adverse effects*
  • Male
  • Middle Aged
  • Parathyroid Hormone / blood
  • Phosphorus / blood
  • Phosphorus / metabolism*
  • Prospective Studies
  • Remission, Spontaneous
  • Time Factors

Substances

  • Parathyroid Hormone
  • Phosphorus
  • Fibroblast Growth Factors
  • fibroblast growth factor 23
  • Calcitriol