Albuminuria

Albuminuria is a pathological condition wherein the protein albumin is abnormally present in the urine. It is a type of proteinuria. Albumin is one type of plasma protein found in the urine in normal subjects and in larger quantity in patients with kidney disease. For a number of reasons, clinical terminology is changing to focus on albuminuria rather than proteinuria.

Symptoms

It is usually assymptomatic but whitish foam may appear in urine. Swelling of the ankles, hands, belly or the face may occur if losses of albumin are important and produce low serum protein levels (nephrotic syndrome).

Measurement

The amount of protein being lost in the urine can be quantified by collecting the urine for 24 hours, measuring a sample of the pooled urine, and extrapolating to the volume collected.

Also a urine dipstick test for proteinuria can give a rough estimate of albuminuria. This is because albumin is by far the dominant plasma protein, and bromphenol blue the agent used in the dipstick is specific to albumin.