Specimen requirement

24 Hr urine:

U1 bottle

Spot urine / 4 Hr urine:

Plain urine bottle

Minimum urine volume: 10 mL

Authorisation code required

No

24 Hr available service

No

Method

Immunoassay

Reference interval

Urine albumin / creatinine ratio: < 3.0 mg/mmol Cr

Urine albumin / creatinine ratio: < 30 mg/g Cr
Urine albumin excretion rate: < 20.8 µg/min
 

(Source: Kidney Disease: Improving Global Outcomes (KDIGO) Diabetes Work Group. KDIGO 2022 Clinical Practice Guideline for Diabetes Management in Chronic Kidney Disease. Kidney Int. 2022; 102(5S): S1 - S127. (PMID: 36272764))

Clinical indication

Early detection of diabetic nephropathy

Investigation and monitoring of renal disease

Result interpretation

Urine albumin is elevated in nephrotic syndrome, in other conditions with increased glomerular permeability (e.g. glomerulonephritis), and in urinary tract inflammation. Elevations can be seen in renal failure following diabetic nephropathy or other causes. It can be used instead of urinary protein to detect or monitor these conditions.

Elevation of urine albumin can be a marker of kidney damage and is found in chronic kidney disease (CKD). According to the 'Kidney Disease: Improving Global Outcomes' (KDIGO) guidelines, albuminuria can be used in diagnosis and staging of CKD.

Albuminuria categories in Chronic Kidney Disease (CKD):

Category	Urine Alb/Cr Ratio (SI Unit) (mg/mmol Cr)	Urine Alb/Cr Ratio (Conventional Unit) (mg/g Cr)	Terms
A1	< 3.0	< 3.0	Normal to mildly increased
A2	3.0 - 30	30 - 300	Moderately increased
A3	> 30	> 300	Severely increased

Nephrotic syndrome:
Urine Alb/Cr Ratio usually >220 mg/mmol Cr (or >2,200 mg/g Cr)

Urine Alb/Cr Ratio (mg/mmol Cr) × 10 is approximately equivalent to Urine Alb/Cr Ratio (mg/g Cr) or Urine Albumin Excretion Rate (mg/day)

Precautions:
Early morning urine specimens are ideal for calculation of the albumin/creatinine ratio, although specimens collected at any time of day may be used. Albumin/creatinine ratio has marked variability; therefore, a confirmatory urine sample is suggested. Possible causes of transient elevations in urine albumin results include hematuria, menstruation, exercise and urinary infection. Patients should avoid vigorous exercise for 24 hours before specimen collection.

Reference:

1. Kidney Disease: Improving Global Outcomes (KDIGO) Diabetes Work Group. KDIGO 2022 Clinical Practice Guideline for Diabetes Management in Chronic Kidney Disease. Kidney Int. 2022; 102(5S): S1 - S127. (PMID: 36272764)
2. Diabetes Management in Chronic Kidney Disease: A Consensus Report by the American Diabetes Association (ADA) and Kidney Disease: Improving Global Outcomes (KDIGO). Diabetes Care. 2022; 45(12): 3075 - 3090. (PMID: 36189689)
3. Kidney Disease: Improving Global Outcomes (KDIGO) CKD Work Group. KDIGO 2024 Clinical Practice Guideline for the Evaluation and Management of Chronic Kidney Disease. Kidney Int. 2024; 105(4S): S117 - S314. (PMID: 38490803)

Measurement of uncertainty

See table.

Frequency of measurement

Daily