Lab Test

Albumin, Urine

Urine Albumin, Urine Microalbumin, Urine Albumin/Creatinine Ratio, Urine Microalbumin/Creatinine Ratio

Test Codes

Random: EPIC: LAB5089, MALBU, Timed: EPIC: LAB6603, MALUT, 24 Hour: EPIC: LAB5445, MAL24

Department

Chemistry

Instructions

Note: 24 hour and random urine specimens MUST be collected separately. See below for collection criteria.

Specimen Collection Criteria

Collect: 24 hour urine or timed urine specimen with a 24 hour urine container with no preservatives.
Also acceptable: Random urine specimen in a screw-capped container (preferred) or another sterile collection cup. Preservatives are not acceptable for random urine specimens. (Minimum: 20 mL)

  • For patients who have difficulty collecting timed urines, a random urine sample for Albumin/Creatinine Ratio, Urine is suggested. A mid-stream collection from the first morning void is recommended. Other random samples are also acceptable.
  • Refer to the table of Urine Preservative Options when multiple tests are requested.
  • Keep 24-hour urine specimen iced or refrigerated during collection.
  • Include start and end dates and times for the collection period on the specimen container.
Urine Preservative Options
No Preservative
6N Hydrochloric Acid
Boric Acid (10g)
Sodium Carbonate
50% Acetic Acid
Preferred
Unacceptable
Unacceptable
Unacceptable
Unacceptable

Physician Office/Draw Specimen Preparation

Maintain specimens refrigerated (2-8°C or 36-46°F) prior to transport.

Preparation for Courier Transport

Transport: Entire 24-hour urine collection, timed urine, or random urine, refrigerated (2-8°C or 36-46°F).

Rejection Criteria

Specimens contaminated with blood (may result in falsely elevated results).

Specimens not collected and processed as indicated.

In-Lab Processing

Measure total volume of 24 hour or timed urine specimen. Record total volume and collection start and end dates and times in the LIS system. Aliquot a minimum of 10 mL from the well-mixed 24 hour or timed urine collection.

Storage

Specimen Stability for Testing:

Room temperature (20-26°C or 68-78.8°F): 4 hours
Refrigerated (2-8°C or 36-46°F): 7 days
Frozen (-20°C/-4°F or below): For longer storage.

Specimen Storage in Department Prior to Disposal:

Refrigerated (2-8°C or 36-46°F): 7 days (Royal Oak and Troy store an aliquot for 30 days.)

Laboratory

Dearborn Chemistry Laboratory
Farmington Hills Chemistry Laboratory
Grosse Pointe Chemistry Laboratory
Royal Oak Automated Chemistry Laboratory
Troy Chemistry Laboratory 

Performed

Sunday – Saturday.
Results available within 24 hours.

Reference Range

Albumin, Urine: Less than 30 mg/24 hours.
Albumin Excretion Rate, Urine: Less than or equal to 20 mcg/minute.
Albumin/Creatinine Ratio, Urine: Less than 30 mg/g.

Test Methodology

Spectrophotometry, Immunoturbidimetry.

Interpretation

  • Microalbuminuria is a term describing the presence of small amounts of albumin in the urine. A timed urine, either 24 hour or overnight (8-12 hour), if collected accurately, is probably the best method for detection of microalbuminuria. However, a random urine for a urine albumin:creatinine ratio is a more practical initial screen.
  • Albuminuria categories in chronic kidney disease:
 Category  Albumin: creatinine ratio (mg/g)    Terms 
 A1  < 30   Normal to mild increase 
 A2  30 - 300   Moderately increased
 A3  > 300   Severely increased

If a patient has =1+ proteinuria (30 mg/dL) by Urine Dipstick (Urinalysis), overt proteinuria is present and testing for albuminuria is inappropriate. In this situation a Urine Protein/Creatinine Ratio or a 24 hour urine collection for Total Protein is appropriate.

Clinical Utility

Microalbuminuria has an important predictive value in determining diabetic patients at risk of developing nephropathy. Microalbuminuria may also be caused by poor metabolic regulation, physical exercise, newly diagnosed diabetes, hypertension, and non-diabetic renal or systemic disease.

Reference

  1. Chronic Kidney Disease and Risk Management: Standards of Medical Care in Diabetes – 2022. Diabetes Care 2022;Volume 45, Supplement, S175-S18.

CPT Codes

82043, 82570.

Contacts

Last Updated

2/8/2022

Microtainer® and Vacutainer® are registered trademarks of Becton, Dickinson and Company.
UroVysion® is a registered trademark of Abbott Laboratories. ThinPrep® is a registered trademark of Hologic, Incorporated.