Diabetic Nephropathy


  • Develops in 20-40% of diabetics and is the leading cause of ESRD
  • Persistent microalbuminuria (30-299 mg/24h) is a marker for the development of diabetic nephropathy in type 2 diabetics
  • Progression to macroalbuminuria (> 300 mg/24h) predicts progression to ESRD
Screening:
  • Should be initiated at time of diagnosis of type 2 diabetes as ~7% already have microalbuminuria
  • Screen type 1 diabetics 1-5 years from initial diagnosis
  • If absent, continue to screen annually
  • Abnormal results should be confirmed with 2 out of 3 samples over 3-6 months due to variability in urine albumin excretion (UAE)
  • Random spot urine for albumin-to-creatinine ratio is preferred
    Normal: < 30 mcg/mg creatinine
    Microalbuminuria: 30-299 mcg/mg
    Macroalbuminuria: >300 mcg/mg
     
  • 4- or 24-hour collections may also be used, but are more cumbersome and are prone to collection error
Management
  • Progression from micro- to macroalbuminuria can be delayed with intensive blood glucose and blood pressure control
  • ACE inhibitors and ARBs are first-line therapy, even if blood pressure is normal
  • Antiproteinemic effect is independent of blood pressure lowering

Diabetes & CKD

  • Use ACE-I or an ARB in normotensive patients with diabetes and albuminuria levels > 30 mg/g who are at high risk of CKD or its progression.
  • Do not use ACE-I or ARB for the primary prevention of CKD in normotensive normoalbuminuric patients with diabetes.
  • Reduction of dietary protein intake to 0.8-1.0 g/kg/d in earlier stages and to 0.8 g/kg/d in later stages of CKD may improve renal function and is recommended