title: Hyperparathyroidism and increased fractional excretion of phosphate predict allograft loss in long-term kidney transplant recipients.
abstract: BACKGROUND
  After kidney transplantation, fibroblast growth factor-23 (FGF-23) normally returns to baseline within 1 year whereas hyperparathyroidism persists in most kidney transplant (KT) recipients. As a result, serum phosphate remains relatively low in association with increased serum calcium and urinary phosphate excretion when compared to chronic kidney disease patients. The relationship between mineral metabolism and outcomes in long-term KT recipients has not been extensively studied. This study investigated whether the alteration in mineral metabolism influenced graft survival in long-term KT recipients.
  
  
  METHODS
  This study included 273 KT recipients after 1 year of transplantation. Mineral parameters were obtained at the time of enrolment and patients were followed prospectively for an average of 71 months.
  
  
  RESULTS
  Graft loss (death-censored) occurred in 41 (15%) patients. In univariate analysis, deceased donor transplantation, decreased serum albumin and estimated glomerular filtration rate, increased serum phosphate, parathyroid hormone (PTH), FGF-23 and fractional excretion of phosphate (FePi) predicted future allograft loss. After adjustments for cardiovascular disease risk factors, donor type, dialysis vintage, serum albumin and allograft function, only increased PTH and FePi remained associated with the outcome. Relationships between increased serum phosphate and FGF-23 with graft survival were lost after adjustments. Adjusted survival curves revealed the association between PTH > 90 pg/mL and FePi > 20% with worse graft survival.
  
  
  CONCLUSIONS
  Hyperparathyroidism and increased FePi predicted allograft loss in long-term KT recipients.
authors.affiliation: Division of Nephrology, Department of Medicine, Faculty of Medicine, Ramathibodi Hospital, Mahidol University, 270 Rama VI Rd, 7th floor, Building 1, Phayathai, Bangkok, 10400, Thailand.
authors.forename: Sumanee
authors.initials: S
authors.lastname: Prakobsuk
authors.affiliation: Division of Nephrology, Department of Medicine, Faculty of Medicine, Ramathibodi Hospital, Mahidol University, 270 Rama VI Rd, 7th floor, Building 1, Phayathai, Bangkok, 10400, Thailand.
authors.forename: Supinda
authors.initials: S
authors.lastname: Sirilak
authors.affiliation: Division of Nephrology, Department of Medicine, Faculty of Medicine, Ramathibodi Hospital, Mahidol University, 270 Rama VI Rd, 7th floor, Building 1, Phayathai, Bangkok, 10400, Thailand.
authors.forename: Kotcharat
authors.initials: K
authors.lastname: Vipattawat
authors.affiliation: Division of Nephrology, Department of Medicine, Faculty of Medicine, Ramathibodi Hospital, Mahidol University, 270 Rama VI Rd, 7th floor, Building 1, Phayathai, Bangkok, 10400, Thailand.
authors.forename: Pahnwat T
authors.initials: PT
authors.lastname: Taweesedt
authors.affiliation: Division of Nephrology, Department of Medicine, Faculty of Medicine, Ramathibodi Hospital, Mahidol University, 270 Rama VI Rd, 7th floor, Building 1, Phayathai, Bangkok, 10400, Thailand.
authors.forename: Vasant
authors.initials: V
authors.lastname: Sumethkul
authors.affiliation: Division of Nephrology, Department of Medicine, Faculty of Medicine, Ramathibodi Hospital, Mahidol University, 270 Rama VI Rd, 7th floor, Building 1, Phayathai, Bangkok, 10400, Thailand.
authors.forename: Surasak
authors.initials: S
authors.lastname: Kantachuvesiri
authors.affiliation: Division of Nephrology, Department of Medicine, Faculty of Medicine, Ramathibodi Hospital, Mahidol University, 270 Rama VI Rd, 7th floor, Building 1, Phayathai, Bangkok, 10400, Thailand. sinee.dis@mahidol.ac.th.
authors.forename: Sinee
authors.initials: S
authors.lastname: Disthabanchong
mesh_terms: D000328:Adult; D064591:Allografts; D005260:Female; D000089703:Fibroblast Growth Factor-23; D005919:Glomerular Filtration Rate; D006085:Graft Survival; D006801:Humans; D006961:Hyperparathyroidism / Q000097:blood / Q000175:diagnosis / Q000209:etiology* / Q000503:physiopathology; D017674:Hypophosphatemia / Q000097:blood / Q000175:diagnosis / Q000209:etiology* / Q000503:physiopathology; D007015:Hypophosphatemia, Familial / Q000175:diagnosis / Q000209:etiology* / Q000503:physiopathology / Q000652:urine; D007668:Kidney / Q000503:physiopathology*; D016030:Kidney Transplantation / Q000009:adverse effects*; D008297:Male; D008875:Middle Aged; D010710:Phosphates / Q000097:blood / Q000652:urine*; D011446:Prospective Studies; D006435:Renal Dialysis; D065667:Renal Elimination; D012307:Risk Factors; D013997:Time Factors; D016896:Treatment Outcome
chemical_list: C000717427:FGF23 protein, human; D010710:Phosphates; D000089703:Fibroblast Growth Factor-23
keywords: Hypercalcemia; Phosphaturia; Renal transplantation; Vitamin D