Comparison of commonly used assays for the detection of microalbuminuria.

There are a variety of methods for assessing urinary albumin excretion, extending from the very low-range microalbuminuria to higher ranges extending into macroalbuminuria or proteinuria. The recommendation for the initial screening of a new patient is to use a urine dipstick to assess for microalbuminuria. If positive, a spot urine for albumin:creatinine should be measured and reassessed annually. All patients with kidney disease, diabetes, or hypertension and metabolic syndrome should be screened for albuminuria. New methodologies using high-performance liquid chromatography are much more sensitive and specific when compared with older methods of detection and may prove very useful for earlier identification of high-risk patients. This is important since studies have shown that albuminuria levels below the microalbuminuria range, determined by conventional methodologies in uncomplicated essential hypertensive men, are associated with an adverse cardiovascular and metabolic risk profile. High performance liquid chromatography methodology, in contrast to older studies, detects all intact albumin and enables clinicians to assess disease severity and monitor therapeutic effectiveness with confidence in the accuracy of the microalbuminuria data reported to them.