What is the significance of a urine albumin‑creatinine ratio of 37 mg/g (albumin 13.8 mg/dL, creatinine 375 mg/dL) and how should it be managed?

Interpretation of Your Urine Albumin-Creatinine Ratio

Your urine albumin-creatinine ratio (ACR) of 37 mg/g indicates moderately increased albuminuria (formerly called microalbuminuria), signaling early kidney damage that requires confirmation with repeat testing and immediate intervention to prevent progression to more severe kidney disease. 1

Understanding Your Results

Your calculated ACR of 37 mg/g falls into the A2 category (moderately increased albuminuria), defined as ACR 30-299 mg/g. 1 This represents:

• Early kidney damage that is detectable before any measurable decline in kidney filtration occurs 2
• Increased cardiovascular risk independent of other risk factors 2
• Higher risk for progression to end-stage kidney disease if left untreated 1, 2

The historic term "microalbuminuria" is no longer recommended for this range. 2

Immediate Next Steps: Confirmation Testing

You must confirm this result with 2 out of 3 first-morning urine samples showing ACR ≥30 mg/g over the next 3-6 months before diagnosing persistent albuminuria. 1, 2 This is critical because day-to-day variability in ACR measurements is substantial—for someone in your range, a change of ±170% can occur due to biological variation alone. 3

Before confirming chronic elevation, exclude these transient causes that can falsely elevate ACR:

• Active urinary tract infection or fever 1, 2
• Congestive heart failure exacerbation 1, 2
• Marked hyperglycemia (high blood sugar) 1, 2
• Menstruation 1, 2
• Uncontrolled hypertension 1, 2
• Exercise within 24 hours 2

Essential Baseline Testing

Measure serum creatinine and calculate estimated glomerular filtration rate (eGFR) using the CKD-EPI equation to determine your baseline kidney function. 2 This will guide monitoring frequency and treatment intensity.

Treatment Recommendations

Pharmacologic Intervention

Start an ACE inhibitor or ARB immediately, regardless of your current blood pressure level, because these medications provide kidney-protective effects beyond simple blood pressure lowering. 1, 2 These agents have specific antiproteinuric effects that reduce albumin leakage. 2

Target blood pressure <130/80 mmHg. 1, 2

Important contraindication: If you are a woman of childbearing age, ACE inhibitors and ARBs are contraindicated unless you are using reliable contraception due to teratogenic effects. 2

Lifestyle Modifications

• Protein restriction to 0.8 g/kg/day (the recommended daily allowance) 2
• Lipid management: LDL cholesterol <100 mg/dL if diabetic, <120 mg/dL otherwise 2
• Limit saturated fat to <7% of total calories 2

Monitoring Schedule Based on Your Kidney Function

Your monitoring frequency depends on your eGFR result:

Your eGFR (mL/min/1.73 m²)	Monitor ACR & eGFR
≥60	Annually [2]
45-59	Every 6 months [2]
30-44	Every 3-4 months [2]
<30	Immediate nephrology referral [2]

Treatment Goals

The therapeutic aim is to reduce your ACR by at least 30-50%, ideally achieving an ACR <30 mg/g. 2 Sustained reduction in albuminuria is a validated surrogate marker for slowed progression of chronic kidney disease. 2

When to See a Kidney Specialist (Nephrologist)

Immediate nephrology referral is indicated if:

• Your eGFR is <30 mL/min/1.73 m² 2
• Your ACR rises to ≥300 mg/g despite treatment 2
• Rapid decline in kidney function occurs 2
• Uncertainty exists regarding the underlying cause of your albuminuria 2
• Inadequate response to optimal ACE-inhibitor/ARB therapy 2
• You require ≥4 antihypertensive medications to control blood pressure 2

Clinical Context and Prognosis

At any level of kidney function, your elevated ACR independently raises the risk of cardiovascular disease, progression to end-stage kidney disease, and all-cause mortality. 2 The risk escalates continuously as ACR rises, even within the moderately increased range. 2

If you have diabetes:

• Type 1 diabetes: This level typically develops after 10+ years and usually accompanies diabetic retinopathy 2
• Type 2 diabetes: This can be present at diagnosis since disease onset is difficult to date precisely 2

Common Pitfalls to Avoid

• Do not dismiss a single elevated ACR result, but also do not overreact—confirm with repeat testing 1, 2
• Do not delay ACE inhibitor/ARB therapy while waiting for confirmation if other clinical features suggest chronic kidney disease 2
• Do not use albumin measurement alone without creatinine, as it is susceptible to false results due to variations in urine concentration 2
• Ensure all urine collections are at the same time of day (preferably first morning void) and that you have not eaten for at least 2 hours prior to minimize variability 1