A 52-year-old diabetic has proteinuria of 4.5 g/day and creatinine of 2.1 mg/dL. Renal biopsy shows diffuse glomerulosclerosis with Kimmelstiel-Wilson nodules and arteriolar hyalinosis affecting the efferent arteriole more than the afferent arteriole. The pathogenic significance of efferent arteriolar hyalinosis in diabetic nephropathy specifically is:
- A It reduces glomerular filtration by decreasing Kf
- B It is pathognomonic of diabetic nephropathy and indicates advanced disease ✓
- C It results from protein precipitation due to high ultrafiltrate protein concentration
- D It indicates coexisting hypertensive nephrosclerosis
Explanation
Efferent arteriolar hyalinosis (also called 'exudative' or 'dropout' arteriolar hyalinosis) is pathognomonic of diabetic nephropathy among the various causes of renal hyalinosis. In hypertensive nephrosclerosis and aging, hyalinosis affects the afferent arteriole; involvement of the efferent arteriole is essentially specific to diabetes mellitus. This efferent arteriolar hyalinosis reflects AGE (advanced glycation end-product) accumulation and protein deposition in the vessel wall, occurring as a consequence of the extreme hyperfiltration and high intraglomerular pressures seen in early-stage diabetic nephropathy.
Reference: Robbins & Cotran Pathologic Basis of Disease, 10th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.