It is used to screen people with chronic conditions, such as diabetes and high blood pressure (hypertension) that put them at an increased risk of developing kidney disease.
Microalbuminuria is a term to describe a moderate increase in the level of urine albumin. It occurs when the kidney leaks small amounts of albumin into the urine, in other words, when there is an abnormally high permeability for albumin in the glomerulus of the kidney. Microalbuminuria can be diagnosed from a 24-hour urine collection (between 30–300 mg/24 hours) or, more commonly, from elevated concentrations in a spot sample (30 to 300 mg/L). A ratio of albumin (mcg/L) to creatinine (mg/L) of less than 30 is normal; a ratio of 30-300 signifies microalbuminuria and values above 300 are considered as macroalbuminuria. On a standard urine dipstick, 10-20 mg/dL is the minimal detection limit of protein. Background. Microalbuminuria is defined as excretion of 30–300 mg of albumin per 24 hours (or 20–200 mcg/min or 30–300 mcg/mg creatinine) on 2 of 3 urine collections. The detection of low levels of albumin excretion (microalbuminuria) has been linked to the identification of incipient diabetic kidney disease. Albumin is a major protein normally present in blood. The urine albumin test detects and measures the amount of albumin in the urine. The presence of a small amount of albumin in the urine may be an early indicator of kidney disease. A small amount of albumin in the urine is sometimes referred to as urine microalbumin or microalbuminuria The purpose of the microalbuminuria test is to measure the amount of albumin in the urine. The test is typically used in conjunction with a creatinine test to provide an albumin-to-creatinine ratio. Creatinine is a waste product in the blood that should be removed by the kidneys. When kidney damage occurs, creatinine levels in the urine decrease while albumin levels may increase. Introduction. Urine albumin to creatinine ratio (ACR), also known as urine microalbumin, helps identify kidney disease that can occur as a complication of diabetes. If kidney disease is diagnosed early in people with diabetes, appropriate treatment can be given and its effects can be closely monitored.  If albumin is detected in a urine sample collected at random, over 4 hours, or overnight, the test may be repeated and/or confirmed with urine that is collected over a 24-hour period (24-hour urine). Creatinine, a byproduct of muscle metabolism, is normally released into the urine at a constant rate and its level in the urine is an indication of the urine concentration. This property of creatinine allows its measurement to be used to correct for urine concentration in a random urine sample. In a properly functioning body, albumin is not normally present in urine because it is retained in the bloodstream by the kidneys. Microalbuminuria can be diagnosed from a 24-hour urine collection (between 30–300 mg/24 hours) or, more commonly, from elevated concentrations in a spot sample (30 to 300 mg/L). Both must be measured on at least two of three measurements over a two-to three-month period The urine albumin test or albumin/creatinine ratio (ACR) is used to screen people with chronic conditions, such as diabetes and high blood pressure (hypertension) that put them at an increased risk of developing kidney disease. Creatinine, a byproduct of muscle metabolism, is normally released into the urine at a constant rate and its level in the urine is an indication of the urine concentration. This property of creatinine allows its measurement to be used to correct for urine concentration in a random urine sample. Another test to check the level of a substance called creatinine in the urine is usually done at the same time. Then the ratio of albumin to creatinine is reported. Creatinine is one of the waste chemicals in the blood that the kidney filters into the urine. This test is done to check for early signs of kidney damage, especially if you have diabetes. When your kidneys are healthy, very little albumin is present in the urine and the microalbumin/creatinine ratio is low. The level of albumin in your urine may be higher than normal because of kidney disease. Common causes of kidney disease include diabetes, high blood pressure, and autoimmune disorder
https://en.wikipedia.org/wiki/Microalbuminuria http://emedicine.medscape.com/article/2088184-overview https://labtestsonline.org/understanding/analytes/microalbumin/tab/sample http://www.healthline.com/health/microalbuminuria-test http://www.nhs.uk/Conditions/Microalbumin-test/Pages/Introduction.aspx https://labtestsonline.org/understanding/analytes/microalbumin/tab/test https://en.wikipedia.org/wiki/Microalbuminuria https://labtestsonline.org/understanding/analytes/microalbumin/tab/test http://www.summitmedicalgroup.com/library/adult_health/aha_microalbumin_test/
understanding albumin creatinine ratio