Abstract: FR-PO0337
Clinicopathological Significance of Interstitial Fibrosis and Tubular Atrophy in Diabetic Nephropathy
Session Information
- Diabetic Kidney Disease: Progression, Predictive Tools, Therapeutics, and Outcomes
November 07, 2025 | Location: Exhibit Hall, Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: Diabetic Kidney Disease
- 702 Diabetic Kidney Disease: Clinical
Authors
- Yasuda, Fumihiko, Nihon Ika Daigaku, Bunkyo, Tokyo, Japan
- Mii, Akiko, Nihon Ika Daigaku, Bunkyo, Tokyo, Japan
- Morita, Megumi, Nihon Ika Daigaku, Bunkyo, Tokyo, Japan
- Kamano, Chisako, Hakujikai Kinen Sogo Byoin, Adachi, Tokyo, Japan
- Shimizu, Akira, Nihon Ika Daigaku, Bunkyo, Tokyo, Japan
Background
Diabetic nephropathy (DN) is defined by characteristic lesions such as diffuse and nodular glomerular lesions and arteriolar hyalinosis, and its progression has traditionally been linked to glomerular injury. However, tubulointerstitial and vascular involvement is also thought to contribute, although these components have been less extensively studied. This study aimed to characterize interstitial and vascular pathology in DN by investigating the association between interstitial fibrosis and tubular atrophy (IFTA), a key indicator of renal dysfunction, and other DN-specific histological features.
Methods
Among 62 adult diabetic patients who underwent renal biopsy at Nippon Medical School between 2008 and 2016, 49 cases with biopsy-proven diabetic nephropathy and no evidence of other renal diseases were included. Clinicopathological analyses were performed with a focus on IFTA.
Results
IFTA (%) showed a strong inverse correlation with estimated glomerular filtration rate (eGFR) and a weak positive correlation with proteinuria. IFTA severity was significantly associated with progression of glomerular lesions, including diffuse lesions, GBM doubling, exudative lesions, mesangiolysis, and glomerulosclerosis. Although nodular lesions were linked to higher IFTA in lesion-positive cases, their frequency did not correlate with IFTA. IFTA also correlated positively with interstitial inflammation and paratubular basement membrane insudative lesions (PTBMIL), a tubular exudative lesion. Arteriolar hyalinosis was associated with increased IFTA and reduced eGFR. In contrast, arteriosclerosis showed no significant correlation with IFTA, eGFR, or RPS 2010 pathological stage. Notably, some cases exhibited IFTA progression in association with arteriosclerosis but without typical DN-related lesions, suggesting diabetic kidney disease (DKD) with predominant macroangiopathic features.
Conclusion
In typical DN, IFTA severity is closely related to renal dysfunction and microangiopathy-driven lesions. However, in certain cases, IFTA appears to be associated with arteriosclerosis, potentially reflecting macroangiopathy-related DKD. These findings highlight the importance of integrated pathological assessment, including glomerular, tubulointerstitial, and vascular lesions, in evaluating DN progression.