Fluorimetric Tool to Discriminate Glomerular and Tubular Injuries In Vivo

The etiology and pathological complexity of acute kidney injury (AKI) pose great challenges for early diagnosis, typing, and personalized treatment. It is an important reason for poor prognosis and high mortality of AKI. In order to provide a relatively noninvasive diagnostic and typing method for AKI, we proposed the pathological changes of albumin permeability after glomerular injury and reabsorption efficiency after tubular injury as potential entry points. Thus, a renal tubule labeling fluorescent dye which features albumin concentration-related fluorescence intensity was used to fit these pathological changes. Utilizing this fluorescence assay, we realized urinary tract obstruction imaging as early as 12 h after morbidity. For glomerular and tubular injury discrimination, compared to a healthy control, membranous nephropathy as a representative glomerular injury resulted in enhanced fluorescence intensity of the kidney due to increased albumin penetration, while renal tubular injury caused insufficient dye reabsorption to exhibit weakened fluorescence intensity. The significant differences demonstrated the feasibility of this approach for fluorescence imaging-based AKI typing in vivo.