People who are considered healthy should only have trace amounts of proteins in their urine. The presence of such proteins, particularly albumin, is a sign of kidney damage often caused by diabetes or high blood pressure. The earlier this kidney damage is diagnosed, the more effective the treatment will be. A microalbuminuria test can detect very small amounts of protein in the urine before the routine test using strips comes up positive. To take into account the water content of each urine sample, microalbuminuria results upon urination are expressed in milligrams of albumin per millimole of creatinine (mg/mmol).
An albumin/creatinine ratio of less than 2.0 mg/mmol (calculation cancelled because microalbumin below detection threshold) is completely normal. Several factors can lead to transient protein excretions: infections, medication use, intense exercise, pregnancy, weight loss diets, exposure to cold, and physical or emotional stress. Repeated results between 2 and 20 mg/mmol are consistent with microalbuminuria and mild kidney damage, while repeated results above 20 mg/mmol are consistent with increased albuminuria or proteinuria, suggesting renal glomerulus damage. Levels higher than 300 mg/mmol (or 3 g per day) are consistent with nephrotic syndrome.