Clinical Significance

Microalbuminuria is the presence of urinary albumin which is quantitatively below the limit of detection of the dipstick albumin but which is above normal. Microalbuminuria is the earliest evidence of diabetic nephropathy and permits detection of this sequel of diabetes at a time in the natural history of the disease when aggressive intervention can significantly delay or prevent the progression of renal injury. Urinary excretion of albumin, like other urinary analytes, is variable throughout the day and dependent on the degree or urine concentration. Published studies have established that normalization of microalbumin to the urine creatinine concentration serves to substantially correct for this variability and provide a clinically useful measure of microabluminuria on random urine samples, obviating the needs for a 24 hour urine collection. Thus, the microalbumin/creatinine ratio has become an established screening test for pathologic excretion of albumin.