Evaluation of Kidney Fibrosis Via FAPI PET/CT

Interstitial fibrosis is a hallmark of progression in chronic kidney disease (CKD), yet it can presently be assessed only by kidney biopsy, which is invasive and prone to sampling error. In recent years the advances in molecular imaging, especially high spatial and temporal resolution of the scanners and the development of radiopharmaceuticals to visualize metabolic processes or immune cells have been significant, opening promising possibilities in multiple fields. It was demonstrated that in autoimmune diseases as Crohns disease the use of fibrosis markers, as 68Ga-FAPI tracer in PET/MRI could adequately reflect the amount of fibrosis found in histologic work up of tissue specimens in the gut. Also first data in small studies including patients with chronic kidney disease showed promising results indicating that tracer uptake could reflect the degree of fibrosis. This study aims to investigate the utility of PET/CT imaging with a \[68Ga\]-DOTA.SA.FAPi tracer to reflect the degree of fibrosis found in the histological work up. We hypothesize that PET/CT findings reflect histological found fibrotic changes in kidney biopsies, potentially offering a superior alternative due to its non-invasive nature and the possibility to capture the entire organ.