title: The Uptake of 18F-FDG by Renal Allograft in Kidney Transplant Recipients Is Not Influenced by Renal Function.
abstract: OBJECTIVE
  F-FDG PET/CT has been recently proposed as a noninvasive tool for the diagnosis of renal allograft acute rejection (AR) in kidney transplant recipients (KTRs). Still, the influence of kidney function on F-FDG uptake by renal grafts remains unknown.
  
  
  METHODS
  We retrospectively identified all KTRs who underwent at least one F-FDG PET/CT. Kidney transplant recipients with documented pyelonephritis or AR were excluded. Estimated glomerular filtration rate (eGFR) was assessed using chronic kidney disease (CKD)-EPI equation. Mean standardized uptake values (SUVmean) of renal graft cortex and aorta were measured in 4 and 1 volumes of interest, respectively. Spearman rank correlation coefficient (ρ) and analysis of variance (ANOVA) were performed.
  
  
  RESULTS
  Eighty-two KTRs underwent F-FDG PET/CT for tumor staging (n = 46), suspected infection (n = 11), or fever of unknown origin (n = 25). Mean eGFR was 50 ± 19 mL/min per 1.73 m, including CKD stage 1 (n = 3), stage 2 (n = 21), stage 3a (n = 20), stage 3b (n = 29), and stage 4 (n = 9). Mean kidney and aorta SUVmean were 1.8 ± 0.2 and 1.7 ± 0.3, respectively. No significant correlation was observed between eGFR and kidney SUVmean (ρ, 0.119; P, 0.28) or aorta SUVmean (ρ, -0.144; P, 0.20). ANOVA showed no difference of kidney (P, 0.62) and aorta (P, 0.85) SUVmean between CKD groups. Mean coefficient of variation (on the basis of kidney SUVmean of >3 consecutive F-FDG PET/CT in 15 patients with no significant change of eGFR) reached 13.1%.
  
  
  CONCLUSIONS
  The uptake of F-FDG by renal allografts within an hour postinjection is not significantly impacted by CKD.
authors.affiliation: From the Divisions of *Nuclear Medicine, and †Nephrology, University of Liege Hospital (ULg CHU), Liège, Belgium.
authors.forename: Alexandre
authors.initials: A
authors.lastname: Jadoul
authors.forename: Pierre
authors.initials: P
authors.lastname: Lovinfosse
authors.forename: Laurent
authors.initials: L
authors.lastname: Weekers
authors.forename: Pierre
authors.initials: P
authors.lastname: Delanaye
authors.forename: Jean-Marie
authors.initials: JM
authors.lastname: Krzesinski
authors.forename: Roland
authors.initials: R
authors.lastname: Hustinx
authors.forename: François
authors.initials: F
authors.lastname: Jouret
mesh_terms: D000368:Aged; D000704:Analysis of Variance; D005260:Female; D019788:Fluorodeoxyglucose F18 / Q000493:pharmacokinetics*; D005919:Glomerular Filtration Rate / Q000502:physiology*; D006084:Graft Rejection / Q000000981:diagnostic imaging*; D006801:Humans; D007668:Kidney / Q000378:metabolism; D007676:Kidney Failure, Chronic / Q000503:physiopathology*; D016030:Kidney Transplantation; D008297:Male; D008875:Middle Aged; D000072078:Positron Emission Tomography Computed Tomography; D019275:Radiopharmaceuticals / Q000493:pharmacokinetics*; D012189:Retrospective Studies; D018709:Statistics, Nonparametric; D014184:Transplantation, Homologous
chemical_list: D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18