title: 31P-magnetic resonance spectroscopy (31P-MRS) of human allografts after renal transplantation.
abstract: BACKGROUND
  31P-Magnetic resonance spectroscopy (31P-MRS) can be used as a non-invasive tool for measuring the relative intracellular concentrations of several phosphorus metabolites in different organs. Various pathological conditions are characterized by different metabolic patterns. We studied the value of 31P-MRS after renal transplantation with both an uneventful and a clinically complicated course.
  
  
  METHODS
  We determined the relative concentrations of phosphate-containing metabolites in renal allografts of humans with 31P-MRS (1.5 Tesla) in the first few weeks after transplantation; 18 patients with an uneventful clinical course and 10 patients who required dialysis after transplantation were examined. Six patients with a stable allograft function 2-3 months after transplantation served as controls.
  
  
  RESULTS
  In patients with primary allograft function, we found a significant correlation between the phosphomonoester/phosphodiester-ratio (PME/PDE) (r = 0.66, r < 0.01) and the time after transplantation, but no correlation between the nucleoside triphosphate (beta-NTP)-concentration (r = -0.11) and the time course. In the patients with primary or early allograft dysfunction caused by histologically proven rejection (n=5), we found a low beta-NTP compared to patients with an uncomplicated clinical course (0.09+/-0.01 vs 0.15+/-0.03), but no differences in the PME/PDE ratio (0.73+/-0.21 vs 0.80+/-0.21). In contrast, the PME/PDE ratio was lowered in three patients with delayed graft function caused by acute tubular necrosis (0.45+/-0.07 vs 0.80+/-0.21), but the beta-NTP concentration was not reduced (0.15+/-0.003 vs 0.15+/-0.03). The 31P-MR spectrum of two patients with cyclosporin A damage was not altered compared to the controls.
  
  
  CONCLUSIONS
  31P-MRS can be used in patients in the early period after renal transplantation. A significant correlation between the PME/PDE ratio and the time course but no change in the beta-NTP concentration was found in patients with primary allograft function in the first 4 weeks after renal transplantation. Different patterns of 31P-MR spectra were observed depending on the different causes of primary and early transplant dysfunction.
authors.affiliation: Department of Internal Medicine IV, Friedrich-Schiller-University, Jena, Germany.
authors.forename: A
authors.initials: A
authors.lastname: Klemm
authors.forename: R
authors.initials: R
authors.lastname: Rzanny
authors.forename: R
authors.initials: R
authors.lastname: Fünfstück
authors.forename: W
authors.initials: W
authors.lastname: Werner
authors.forename: J
authors.initials: J
authors.lastname: Schubert
authors.forename: W A
authors.initials: WA
authors.lastname: Kaiser
authors.forename: G
authors.initials: G
authors.lastname: Stein
mesh_terms: D000328:Adult; D016572:Cyclosporine / Q000009:adverse effects; D005260:Female; D006084:Graft Rejection / Q000378:metabolism; D006801:Humans; D007166:Immunosuppressive Agents / Q000009:adverse effects; D007668:Kidney / Q000187:drug effects / Q000378:metabolism*; D016030:Kidney Transplantation; D007683:Kidney Tubular Necrosis, Acute / Q000209:etiology / Q000628:therapy; D009682:Magnetic Resonance Spectroscopy; D008297:Male; D008875:Middle Aged; D009994:Osmolar Concentration; D010710:Phosphates / Q000378:metabolism; D010758:Phosphorus; D011183:Postoperative Complications / Q000628:therapy; D011184:Postoperative Period; D014184:Transplantation, Homologous
chemical_list: D007166:Immunosuppressive Agents; D010710:Phosphates; D010758:Phosphorus; D016572:Cyclosporine