title: Localized 31P MR spectroscopy of the transplanted human kidney in situ shows altered metabolism in rejection and acute tubular necrosis.
abstract: The purpose of this study was to investigate the function of transplant kidneys in situ, and to detect pathologic changes, using volume-selective phosphorous NMR spectroscopy (31P MRS). Localized 31P MR spectra were obtained from 37 patients using a whole-body MR scanner with a combination of surface coils, adiabatic excitation pulses, and a modified image-selected in vivo spectroscopy (ISIS) sequence. Seventeen patients with pathologic changes after renal transplant were compared with a control group of 20 patients with no evidence of transplant dysfunction. The transplant kidneys with rejection reaction showed higher ratios of inorganic phosphate (P2i) to adenosine triphosphate-alpha (ATP-alpha) than the normal control group (.4 +/- .16 compared with .22 +/- .11, P = .01) and reduced pH. The spectra of transplant kidneys with tubular necrosis had lower phosphomonoester (PME)/phosphodiester (PDE) ratios than the control group (.65 +/- .35 compared with .96 +/- .5, P = .04). The pathologies of rejection and tubular necrosis could be differentiated from each other by pH (6.93 +/- .1 in rejection versus 7.14 +/- .19 in tubular necrosis, P = .04). Preliminary results indicate that localized image-guided 31P MR spectroscopy of transplant kidneys in situ can detect rejection reactions and acute tubular necrosis noninvasively, providing an incentive for further research.
authors.affiliation: Department of Diagnostic Radiology, University of Cologne, Köln (Lindenthal), Federal Republic of Germany.
authors.forename: W
authors.initials: W
authors.lastname: Heindel
authors.forename: H
authors.initials: H
authors.lastname: Kugel
authors.forename: F
authors.initials: F
authors.lastname: Wenzel
authors.forename: D
authors.initials: D
authors.lastname: Stippel
authors.forename: R
authors.initials: R
authors.lastname: Schmidt
authors.forename: K
authors.initials: K
authors.lastname: Lackner
mesh_terms: D000255:Adenosine Triphosphate / Q000378:metabolism; D000328:Adult; D000368:Aged; D003937:Diagnosis, Differential; D005260:Female; D006084:Graft Rejection / Q000378:metabolism* / Q000473:pathology*; D006801:Humans; D016030:Kidney Transplantation / Q000502:physiology*; D007683:Kidney Tubular Necrosis, Acute / Q000473:pathology*; D009682:Magnetic Resonance Spectroscopy; D008297:Male; D008875:Middle Aged; D010761:Phosphorus Radioisotopes / Q000378:metabolism; D012680:Sensitivity and Specificity; D018709:Statistics, Nonparametric
chemical_list: D010761:Phosphorus Radioisotopes; D000255:Adenosine Triphosphate