{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,20]],"date-time":"2026-08-20T09:24:23Z","timestamp":1787217863859,"version":"build-2736575974"},"reference-count":36,"publisher":"MDPI AG","issue":"16","license":[{"start":{"date-parts":[[2026,8,20]],"date-time":"2026-08-20T00:00:00Z","timestamp":1787184000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Diagnostics"],"abstract":"<jats:p>Objectives: To evaluate 18F-labelled fluoroazomycinarabinoside ([18F]F-FAZA) PET in post-transplant patients and examine the association of its kinetic and uptake parameters with kidney allograft function measurements, including laboratory and histopathological assessments. Methods: In this prospective pilot study, renal transplant patients were evaluated with a dedicated positron emission tomography\/magnetic resonance imaging (PET\/MR) protocol between 2018 and 2023. Twenty patients with impaired kidney allograft function (cases) and ten sex- and time-post-transplant-matched control patients with stable transplant allograft function (controls) were included. All patients underwent [18F]F-FAZA PET\/MR, including initial dynamic and delayed static imaging. Cases underwent an ultrasound-guided biopsy for histopathological assessments. Results: From the [18F]F-FAZA PET-derived parameters, dynamic total volume distribution (VT) was significantly higher in control patients than in cases (2.11 \u00b1 0.55 vs. 1.62 \u00b1 0.45; p = 0.026). When correlating [18F]F-FAZA PET parameters with creatinine levels and estimated glomerular filtration rate, VT was again the only variable that significantly correlated with both metrics. Regarding histopathological parameters, a significant positive correlation was found between k1 and vascular fibrous intimal thickening, a significant negative correlation between k3 and arteriolar hyalinosis, and k3\/k4 (binding potential) was significantly correlated with the percentage of globally sclerotic glomeruli and arteriolar hyalinosis. Additionally, VT was significantly correlated with interstitial inflammation. SUVmean on the static PET was significantly correlated with the percentage of globally sclerotic glomeruli. Conclusions: Non-invasive assessment of renal microcirculation using dynamic [18F]F-FAZA PET is potentially feasible. The dynamic PET-derived parameters showed strong correlations with renal function. There were also correlations with various histopathological findings. Additionally, static [18F]F-FAZA PET-derived parameters showed complementary findings with hypoxia-related end-stage histopathological indicators.<\/jats:p>","DOI":"10.3390\/diagnostics16162655","type":"journal-article","created":{"date-parts":[[2026,8,20]],"date-time":"2026-08-20T08:10:20Z","timestamp":1787213420000},"page":"2655","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["First Experience with [18F]FAZA PET Imaging in Kidney Allograft Dysfunction"],"prefix":"10.3390","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-2271-9764","authenticated-orcid":false,"given":"Seyed Ali","family":"Mirshahvalad","sequence":"first","affiliation":[{"name":"University Medical Imaging Toronto (UMIT), Toronto Joint Department of Medical Imaging (JDMI), University Health Network (UHN), Sinai Health System & Women\u2019s College Hospital, Department of Medical Imaging, University of Toronto, Toronto, ON M5G 2N2, Canada"},{"name":"Department of Medical Imaging, Health Sciences North, Northern Ontario School of Medicine University, Sudbury, ON P3E 5J1, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8439-9498","authenticated-orcid":false,"given":"Adam","family":"Farag","sequence":"additional","affiliation":[{"name":"University Medical Imaging Toronto (UMIT), Toronto Joint Department of Medical Imaging (JDMI), University Health Network (UHN), Sinai Health System & Women\u2019s College Hospital, Department of Medical Imaging, University of Toronto, Toronto, ON M5G 2N2, Canada"},{"name":"Department of Medical Imaging, The Temerty Faculty of Medicine, University of Toronto, Toronto, ON M5S 1A8, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shenghui","family":"Su","sequence":"additional","affiliation":[{"name":"Toronto General Hospital Research Institute, University Health Network, Toronto, ON M5G 2C4, Canada"},{"name":"Ajmera Transplant Centre, University Health Network, Toronto, ON M5G 2C4, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Olusegun","family":"Famure","sequence":"additional","affiliation":[{"name":"Toronto General Hospital Research Institute, University Health Network, Toronto, ON M5G 2C4, Canada"},{"name":"Ajmera Transplant Centre, University Health Network, Toronto, ON M5G 2C4, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yanhong","family":"Li","sequence":"additional","affiliation":[{"name":"Toronto General Hospital Research Institute, University Health Network, Toronto, ON M5G 2C4, Canada"},{"name":"Ajmera Transplant Centre, University Health Network, Toronto, ON M5G 2C4, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"S. Joseph","family":"Kim","sequence":"additional","affiliation":[{"name":"Ajmera Transplant Centre, University Health Network, Toronto, ON M5G 2C4, Canada"},{"name":"Division of Nephrology, Department of Medicine, University Health Network, Toronto, ON M5G 2C4, Canada"},{"name":"Institute of Health Policy, Management and Evaluation, Dalla Lana School of Public Health, University of Toronto, Toronto, ON M5T 3M7, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hong Sang","family":"Choi","sequence":"additional","affiliation":[{"name":"Toronto General Hospital Research Institute, University Health Network, Toronto, ON M5G 2C4, Canada"},{"name":"Ajmera Transplant Centre, University Health Network, Toronto, ON M5G 2C4, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rohan","family":"John","sequence":"additional","affiliation":[{"name":"Toronto General Hospital Research Institute, University Health Network, Toronto, ON M5G 2C4, Canada"},{"name":"Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON M5S 1A8, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ana","family":"Konvalinka","sequence":"additional","affiliation":[{"name":"Toronto General Hospital Research Institute, University Health Network, Toronto, ON M5G 2C4, Canada"},{"name":"Ajmera Transplant Centre, University Health Network, Toronto, ON M5G 2C4, Canada"},{"name":"Division of Nephrology, Department of Medicine, University Health Network, Toronto, ON M5G 2C4, Canada"},{"name":"Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON M5S 1A8, Canada"},{"name":"Institute of Medical Science, University of Toronto, Toronto, ON M5S 3H2, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Patrick","family":"Veit-Haibach","sequence":"additional","affiliation":[{"name":"University Medical Imaging Toronto (UMIT), Toronto Joint Department of Medical Imaging (JDMI), University Health Network (UHN), Sinai Health System & Women\u2019s College Hospital, Department of Medical Imaging, University of Toronto, Toronto, ON M5G 2N2, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,8,20]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"623","DOI":"10.2215\/CJN.01371005","article-title":"Medical care of kidney transplant recipients after the first posttransplant year","volume":"1","author":"Djamali","year":"2006","journal-title":"Clin. 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