The best way to discern small quantities of urinary protein loss is to check for one protein and place it into a ratio with the chemical that defines the effectiveness of kidney function...albumin/creatinine ratio. This test is ordinarily performed on random (rather than 24-hour collections) urines which are "dipstick negative" for albumin...or for serial follow up testing in cases (1) in which microalbumin screening was positive or (2) the "dipstick" urine had been positive and is now negative. [back to urine tests, protein]

The American Diabetes Association position statement on diabetic nephropathy states that "microalbuminuria" is present if the ratio exceeds 30mg alb./mg of creatinine. The low threshold for non-micro albumin loss (clinical albuminuria...macroalbuminuria) is 300mg alb/mg creatinine. And, because of the many potential non-diabetic and possibly insignificant causes of episodes of albumin "leak" into the urine, the classification of a patient should be based on positive findings on several occasions over a 3-6 month period.

Most of our CMCs use Bayer's DCA 2000 Microalbumin test. The instrument test time is 7 minutes, and it gives a quantitative result in mg alb/g creatinine.

(posted 2002; latest update 29 September 2003)