What is the workup for a patient with diabetes and an elevated Microalbumin to Creatinine Ratio (MAUR)?

Workup for Elevated Microalbumin to Creatinine Ratio (MAUR) in Patients with Diabetes

The workup for a patient with diabetes and elevated microalbumin to creatinine ratio should include confirmation of persistent albuminuria with repeat testing, assessment of kidney function, evaluation of comorbidities, and implementation of renoprotective interventions. 1

Initial Assessment

Confirmation of Albuminuria

• Obtain two additional urine samples over a 3-6 month period to confirm persistent microalbuminuria
  • Microalbuminuria is defined as UACR 30-299 mg/g creatinine
  • Macroalbuminuria is defined as UACR ≥300 mg/g creatinine 1
• Morning spot urine samples are preferred for UACR measurement 1
• Two of three specimens must be abnormal to confirm the diagnosis 1

Comprehensive Kidney Function Assessment

• Measure serum creatinine to estimate glomerular filtration rate (eGFR) 1
• Assess for other manifestations of kidney damage 1
• Rule out non-diabetic causes of kidney disease if:
  • Absence of diabetic retinopathy
  • Rapid decline in eGFR
  • Rapidly increasing proteinuria
  • Refractory hypertension
  • Active urinary sediment
  • Signs or symptoms of other systemic disease 1

Additional Evaluations

Cardiovascular Risk Assessment

• Blood pressure measurement (target <130/80 mmHg for patients with albuminuria) 2
• Lipid profile
• Assessment for other cardiovascular risk factors 1

Glycemic Control Evaluation

• HbA1c measurement (target <7.0%) 3
• Review of current diabetes management 1

Comorbidity Assessment

• Screen for diabetic retinopathy 1
• Evaluate for diabetic neuropathy 1
• Check for hypertension 1

Management Plan Based on UACR Results

For Confirmed Microalbuminuria (UACR 30-299 mg/g)

1. Optimize glycemic control 1
2. Initiate ACE inhibitor or ARB therapy if hypertensive 1
3. Dietary protein intake of approximately 0.8 g/kg body weight per day 1
4. Blood pressure control with target <130/80 mmHg 2
5. Regular monitoring of serum creatinine and potassium levels after starting ACE inhibitors or ARBs 1

For Macroalbuminuria (UACR ≥300 mg/g)

1. All interventions listed for microalbuminuria
2. Strongly recommended ACE inhibitor or ARB therapy 1
3. Consider SGLT2 inhibitor if eGFR ≥30 mL/min/1.73 m² 1
4. Consider GLP-1 receptor agonist for additional renal protection 1
5. More frequent monitoring of kidney function 1

For Patients with eGFR <60 mL/min/1.73 m²

1. Evaluate and manage potential complications of CKD 1
2. Consider nephrology referral, especially if:
   • Uncertain etiology of kidney disease
   • Difficult management issues
   • Rapidly progressing kidney disease
   • eGFR <30 mL/min/1.73 m² 1

Ongoing Monitoring

• Continue annual UACR testing to assess treatment response and disease progression 1
• Regular monitoring of serum creatinine and potassium when using ACE inhibitors, ARBs, or diuretics 1
• Adjust medication dosages based on kidney function 1
• Annual comprehensive diabetic evaluation including retinopathy screening 1

Common Pitfalls to Avoid

• Do not rely on a single elevated UACR reading; confirm with repeat testing 1
• Avoid testing during conditions that may falsely elevate UACR:
  • Exercise within 24 hours
  • Fever or infection
  • Heart failure exacerbation
  • Marked hyperglycemia
  • Marked hypertension 1
• Do not discontinue ACE inhibitors or ARBs for minor increases in serum creatinine (<30%) in the absence of volume depletion 1
• Avoid combining ACE inhibitors with ARBs as this increases risk of hyperkalemia and acute kidney injury without additional benefit 2
• Avoid NSAIDs in patients with elevated UACR due to increased risk of acute kidney injury 2