Test Overview

A microalbumin test evaluates urine for the presence of a protein called albumin. Albumin is normally found in the blood and filtered by the kidneys. When the kidneys are working properly, albumin is not present in the urine. However, when the kidneys are damaged by diabetes, small amounts of albumin leak into the urine. This condition is called microalbuminuria. If blood sugar levels remain high and early kidney damage is not treated, larger amounts of albumin may leak into the urine. This condition is called macroalbuminuria. Macroalbuminuria indicates serious kidney damage that can lead to kidney failure.

A microalbumin urine test can be done on a sample of urine collected randomly (usually after the first time you urinate in the morning), on a sample of urine collected over a 24-hour period, or on a sample of urine collected over a specific period of time, such as 4 hours or overnight.