Abstract: FR-PO644

The Role of the Renal Biopsy in 6003 Patients with Diabetic Nephropathy

Session Information

Category: Diabetes

  • 502 Diabetes Mellitus and Obesity: Clinical

Authors

  • Dai, Dao-Fu, Arkana Laboratories, Little Rock, Arkansas, United States
  • Sharma, Shree G., Arkana Laboratories, Little Rock, Arkansas, United States
  • Larsen, Christopher Patrick, Arkana Laboratories, Little Rock, Arkansas, United States
  • Walker, Patrick D., Arkana Laboratories, Little Rock, Arkansas, United States
Background

Diabetic nephropathy (DN) is a leading cause of end stage renal disease (ESRD). Proteinuria and progressive decline in renal function in patients with diabetes mellitus (DM) are usually thought to be secondary to DN. However, recognition of superimposed non-diabetic renal disease (NDRD) is critical and, with appropriate diagnosis and treatment, may prevent accelerated progression to ESRD.

Methods

This was a retrospective clinical pathological study of 6003 patients with DM and a biopsy diagnosis of DN, to determine the spectrum of superimposed NDRD and to evaluate the relationship between the presence or absence of NDRD with various clinical manifestations, including rapid worsening of proteinuria and renal function, hematuria with or without an active urine sediment, or the acute nephritic syndrome.

Results

The renal biopsy identified superimposed NDRD in 36.6% of patients with DN. Importantly, the biopsy excluded NDRD in 16.7% of patients with systemic diseases and clinical/laboratory findings suspicious for a superimposed disease. Multivariate analysis identified that a rapid rise in serum creatinine is the strongest predictor for superimposed NDRD (OR: 2.19, p<0.001). Other independent predictors include the acute nephritic syndrome and clinical features suspicious for NDRD. The spectrum of superimposed NDRD varied according to indications leading to renal biopsy. Acute tubular injury (21%) was most common in patients with rapid decline of renal function; focal segmental glomerulosclerosis was most common (7.1%) in patients with an unexpected swift rise in proteinuria; pauci-immune crescentic glomerulonephritis (15.7%) was most common in patients with rapidly progressive renal failure; infection-associated glomerulonephritis (16.5%) was most common in patients with the acute nephritic syndrome and IgA nephropathy was the most common in patients with hematuria (7.6%).

Conclusion

The renal biopsy is critical to identify the presence or absence of a superimposed NDRD in patients with DN. This study documents the relationship between various clinical manifestations of renal disease and specific NDRD. Finally, it demonstrates the importance of the biopsy in ruling in or out suspected non-diabetic renal disease in clinical settings that would support such a concern.