title: Renal function and tubular phosphate handling in long-term cyclosporine- and tacrolimus-based immunosuppression in kidney transplantation.
abstract: The aim of the study was to assess impaired tubular phosphate reabsorption and renal function among patients on cyclosporine- or tacrolimus-based immunosuppression for 2 years after kidney transplantation. Among 60 cadaveric kidney allograft recipients observed for 48 months, 40 received cyclosporine, azathioprine, and prednisone (group A and B). Group C consisted of 20 patients receiving tacrolimus with steroid withdrawal at 3 months after transplantation. Renal function and calcium-phosphate metabolism-iPTH, 25-OHD, 1,25(OH)(2)D concentration, phosphate reabsorption (TRP; mmol/L), and tubular maximum phosphate reabsorption per glomerular filtration rate (TmPO(4)/GFR; mmol/L)-were assessed at 1, 6, 12, 18, and 24 months (groups A and C) or 24, 30, 36, 42, and 48 months (group B). Renal function after 24 months of observation was significantly better among tacrolimus-treated patients (serum creatinine concentration mumol/L; C: 94.6 +/- 16.8 vs A: 110.5 +/- 22.1 vs B: 121.1 +/- 30.9; P < .05). Among tacrolimus-treated recipients, TRP and TmPO(4)/GFR remained within normal values during the whole observation period. In groups A and B, TRP improved during the first year of observation; after 2 years it reached values observed in group C (TRP: A: 0.67 +/- 0.1; B: 0.72 +/- 0.13; C: 0.76 +/- 0.07; P = NS), whereas TmPO(4)/GFR remained low in group A after 2 years (A: 0.78 +/- 0.19; B: 0.91 +/- 0.25; C: 0.94 +/- 0.15; P < .05). Tacrolimus-treated patients exhibit significantly faster recovery from tubular phosphate reabsorption impairment compared with cyclosporine-treated recipients. Tacrolimus-based immunosuppression led to better kidney allograft function during 2-year observation.
authors.affiliation: Department of Nephrology and Transplantation Medicine, Wroclaw Medical University, ul. Traugutta 57/59, 50-417 Wroclaw, Poland. klinef@am.centrum.pl
authors.forename: K
authors.initials: K
authors.lastname: Falkiewicz
authors.forename: D
authors.initials: D
authors.lastname: Kamińska
authors.forename: W
authors.initials: W
authors.lastname: Nahaczewska
authors.forename: M
authors.initials: M
authors.lastname: Boratyńska
authors.forename: H
authors.initials: H
authors.lastname: Owczarek
authors.forename: M
authors.initials: M
authors.lastname: Klinger
authors.forename: M
authors.initials: M
authors.lastname: Woźniak
authors.forename: D
authors.initials: D
authors.lastname: Patrzałek
authors.forename: P
authors.initials: P
authors.lastname: Szyber
mesh_terms: D000328:Adult; D002102:Cadaver; D002112:Calcifediol / Q000097:blood; D002117:Calcitriol / Q000097:blood; D002118:Calcium / Q000097:blood; D003404:Creatinine / Q000097:blood; D016572:Cyclosporine / Q000627:therapeutic use*; D004359:Drug Therapy, Combination; D005260:Female; D005919:Glomerular Filtration Rate; D006801:Humans; D007165:Immunosuppression Therapy / Q000379:methods; D007677:Kidney Function Tests; D016030:Kidney Transplantation / Q000276:immunology / Q000502:physiology*; D007684:Kidney Tubules / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D010710:Phosphates / Q000097:blood / Q000378:metabolism*; D012189:Retrospective Studies; D016559:Tacrolimus / Q000627:therapeutic use*; D014019:Tissue Donors
chemical_list: D010710:Phosphates; D016572:Cyclosporine; D003404:Creatinine; D002117:Calcitriol; D002112:Calcifediol; D002118:Calcium; D016559:Tacrolimus