Abstract: SA-PO0857
Kidney Biopsy in Patients with Diabetes: A 30-Year Single-Center Study
Session Information
- Glomerular Diseases: Management, Evolving Strategies, and Practice-Changing Advances
October 24, 2026 | Location: Exhibit Hall A, Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: Glomerular Diseases
- 1402 Glomerular Diseases: Clinical, Outcomes, and Therapeutics
Authors
- Lepori, Nicola, Universita degli Studi di Cagliari, Cagliari, Sardinia, Italy
- Angioi, Andrea, Azienda Ospedaliera Brotzu, Cagliari, Sardinia, Italy
- Floris, Matteo, Universita degli Studi di Cagliari, Cagliari, Sardinia, Italy
- Piras, Doloretta, Azienda Ospedaliera Brotzu, Cagliari, Sardinia, Italy
- Bianco, Paola, Azienda Ospedaliera Brotzu, Cagliari, Sardinia, Italy
- Cabiddu, Gianfranca, Universita degli Studi di Cagliari, Cagliari, Sardinia, Italy
- Pani, Antonello, Universita degli Studi di Cagliari, Cagliari, Sardinia, Italy
Background
Diabetic kidney disease (DKD) is clinically heterogeneous, and kidney biopsy may disclose diabetic nephropathy (DN), non-diabetic renal disease (NDRD), or mixed lesions (DN+NDRD). We evaluated histologic diagnoses, predictors of NDRD, and long-term kidney outcomes in biopsied patients with diabetes.
Methods
We retrospectively analyzed native kidney biopsies performed at ARNAS G. Brotzu Hospital, Cagliari, Italy, from January 1995 to December 2024. Patients >12 years with type 1 or type 2 diabetes or newly detected fasting hyperglycemia and complete baseline data were included. Clinical presentation, laboratory data, histology, comorbidities, diabetic retinopathy, follow-up eGFR, and end-stage kidney disease (ESKD) were collected. Histology was grouped as DN, NDRD, or DN+NDRD.
Results
Among 2678 native kidney biopsies, 250 diabetic patients were included. Mean age was 60.9+/-14.3 years, 67.6% were male, mean eGFR was 40.7+/-33.2 mL/min/1.73 m2, mean proteinuria was 4.5+/-5 g/day, and hematuria was present in 53.2%. The main indications were nephrotic syndrome (28.8%), isolated proteinuria (20%), acute kidney injury (15.2%), chronic kidney disease (14%), rapidly progressive glomerulonephritis (13.2%), and nephritic syndrome (8.8%). Histology showed isolated DN in 88 patients (35.2%), NDRD in 113 (45.2%), DN+NDRD in 38 (15.2%), normal findings in 3 (1.2%), and non-diagnostic or unavailable reports in 9 (3.6%). In isolated NDRD, membranous nephropathy was the most frequent diagnosis (18.6%); in DN+NDRD, tubulointerstitial nephritis predominated (29.7%). In logistic regression, older age predicted NDRD (OR 1.031, p=0.023), whereas diabetic retinopathy (OR 0.221, p<0.001) and CKD as clinical presentation (OR 0.165, p=0.005) were negative predictors. Follow-up data were available for 202 patients over 169.9+/-110 months; 78 (38.6%) reached ESKD. ESKD occurred in 50.8% of DN, 48.4% of DN+NDRD, and 25.6% of NDRD patients. DN conferred higher ESKD risk than NDRD (OR 2.85, p=0.0082)
Conclusion
In this long-term biopsy cohort, NDRD was more frequent than isolated DN, highlighting the diagnostic value of biopsy in diabetic patients with atypical kidney disease. Diabetic retinopathy and CKD presentation supported DN, whereas older age favored NDRD. Histologic classification was clinically relevant and identified patients at higher risk of ESKD.