An 80-year-old woman has a urine albumin‑creatinine ratio of 109 mg/g (microalbuminuria) with otherwise normal laboratory results. What is the diagnosis and recommended treatment?

Diagnosis and Management of Moderately Increased Albuminuria in an 80-Year-Old Woman

This patient has moderately increased albuminuria (formerly called microalbuminuria) with an albumin-to-creatinine ratio of 109 mg/g, which requires confirmation with repeat testing and immediate initiation of ACE inhibitor or ARB therapy regardless of blood pressure status. 1

Diagnostic Confirmation

Obtain two additional first-morning urine samples over the next 3–6 months; persistent albuminuria is confirmed when ≥2 of 3 samples show ACR ≥30 mg/g. 2

• First-morning void specimens minimize variability from orthostatic proteinuria and hydration status. 2, 3
• Before confirming chronic elevation, exclude transient causes:
  • Urinary tract infection (treat and retest after resolution) 2
  • Fever or acute illness 2
  • Recent vigorous exercise within 24 hours 2, 4
  • Marked hyperglycemia 2
  • Congestive heart failure 2
  • Marked hypertension 2

Measure serum creatinine and calculate estimated glomerular filtration rate (eGFR) using the CKD-EPI equation to assess overall kidney function. 1

Risk Stratification

An ACR of 109 mg/g places this patient in the A2 category (moderately increased albuminuria: 30–299 mg/g), which indicates: 1

• Early kidney damage with increased risk for progression to severely increased albuminuria (≥300 mg/g) 1, 5
• Elevated cardiovascular disease risk and all-cause mortality, independent of eGFR 1, 4
• In type 2 diabetes, hypertension and declining renal function may occur even at this level of albuminuria 5

Immediate Pharmacologic Treatment

Start an ACE inhibitor or an ARB immediately once persistent albuminuria is confirmed, regardless of baseline blood pressure. 1, 2, 5

• These agents reduce albuminuria and slow CKD progression through mechanisms beyond blood pressure lowering. 2, 5, 4
• Do not combine an ACE inhibitor with an ARB—the combination increases risk of hyperkalemia and acute kidney injury without added renal benefit. 1
• Target blood pressure <130/80 mmHg in all patients with confirmed albuminuria. 1, 2, 4

Monitor serum creatinine and potassium 1–2 weeks after starting therapy, then periodically. 2

• A creatinine rise ≤30% does not require discontinuation if the patient is euvolemic. 2

Glycemic Control (If Diabetic)

• Target HbA1c <7% to reduce risk and slow progression of diabetic kidney disease. 1, 2, 5
• Consider adding an SGLT2 inhibitor or GLP-1 receptor agonist in type 2 diabetes, as these classes reduce CKD progression and cardiovascular events. 2

Lifestyle Modifications

• Restrict dietary protein to approximately 0.8 g/kg/day (the recommended daily allowance). 2, 4
• Limit sodium intake to <2 g/day to enhance the antiproteinuric effect of RAAS blockade. 4
• Provide intensive smoking cessation counseling—smoking accelerates kidney damage. 2
• Target LDL cholesterol <100 mg/dL if diabetic, <120 mg/dL otherwise; limit saturated fat to <7% of calories. 2

Monitoring Schedule

Re-measure ACR at 6 months after therapy initiation to assess response. 2

• If significant reduction is observed, transition to annual ACR and eGFR testing. 1, 2
• If no reduction occurs, reassess blood pressure control, medication adherence, and consider regimen modification. 2

Monitoring frequency based on eGFR: 1

eGFR (mL/min/1.73 m²)	Monitoring Frequency
≥60	Annually
45–59	Every 6 months
30–44	Every 3–4 months
<30	Immediate nephrology referral

Perform annual dilated retinal examination for diabetic retinopathy, which frequently coexists with diabetic kidney disease. 2

Nephrology Referral Criteria

Refer to a nephrologist when: 1, 2

• eGFR <30 mL/min/1.73 m² for evaluation of renal replacement therapy
• Rapidly increasing albuminuria or progression to ACR ≥300 mg/g despite optimal therapy
• Rapid decline in eGFR
• Uncertainty about etiology of kidney disease (heavy proteinuria, active urine sediment, absence of retinopathy)
• Difficult management issues (resistant hypertension, anemia, electrolyte disturbances)

Common Pitfalls to Avoid

Do not wait for hypertension to develop before starting ACE inhibitor or ARB therapy—these agents are indicated for moderately increased albuminuria even with normal blood pressure. 2, 5, 4

Do not rely on a single ACR measurement—biological variability exceeds 20%, necessitating confirmation with multiple samples over 3–6 months. 2, 6

Do not measure albumin concentration alone without creatinine correction, as hydration status produces false results. 2, 3

In an 80-year-old woman, do not assume normal kidney function based on "normal" serum creatinine alone—always calculate eGFR, as older women have reduced muscle mass and lower creatinine generation. 1