Lab

Urine Microalbumin

Urine Microalbumin, Microalbuminuria, Macroalbuminuria, Urine Microalbumin to Creatinine Ratio, Urine Albumin to Creatinine Ratio

Diabetes Mellitus
Hypertension
1. Questionable efficacy as prognostic factor in Hypertension (contrast with Diabetes Mellitus)

Nephropathy diagnosis needs 2 of 3 samples positive
Typically performed as a Urine Albumin to Creatinine Ratio (random spot urine collection)
Consider postural Proteinuria (especially in adolescents)
1. Obtain overnight timed urine collection

Normal (or mildly increased)
1. 24h Collection: <30 mg/day
2. Timed Collection: <20 mcg/min
3. Urine Albumin to Creatinine Ratio (Spot Collection): <30 mcg/mg Creatinine
Microalbuminuria (moderately increased)
1. 24h Collection: 30-300 mg/day
2. Timed Collection: 20-200 mcg/min
3. Urine Albumin to Creatinine Ratio (Spot Collection): 30-300 mcg/mg Creatinine
Macroalbuminuria (severely increased)
1. 24h CollecSpot Collectiontion: >300 mg/day
2. Timed Collection: >200 mcg/min
3. Urine Albumin to Creatinine Ratio (Spot Collection): >300 mcg/mg Creatinine

Preferred over Urine Protein to Creatinine Ratio
1. Higher Test Sensitivity (esp. at lower albumin levels) than Urine Protein to Urine Creatinine Ratio
2. Widespread standardization across lab assays and countries
Normal Ratio (in general <30 mg/g is normal)
1. Men: < 0.017 (or 17 mg albumin to 1 gram Creatinine)
2. Women: <0.025 (or 25 mg albumin to 1 gram Creatinine)
Microalbuminuria (moderately increased): 30-300 mg albumin/g Creatinine
Macroalbuminuria (severely increased): >300 mg albumin/g Creatinine
False Positive causes