The level of albumin
protein produced by microalbuminuria can be detected by special albumin-specific
urine dipsticks, which have a lower detection threshold than standard urine dipsticks. A
microalbumin urine test determines the presence of the albumin in urine. 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 and 300 mg/24 hours) or, more commonly, from elevated concentration 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. An albumin level above the upper limit values is called "macroalbuminuria", or sometimes just
albuminuria. Sometimes, the upper limit value is given as one less (such as 300 being given as 299) to mark that the higher value (here 300) is defined as macroalbuminuria. and microalbuminuria is defined as ACR ≥3.5 mg/mmol (female) or ≥2.5 mg/mmol (male), or with both substances measured by mass, as an ACR between 30 and 300 μg albumin/mg creatinine. For the diagnosis of microalbuminuria, care must be taken when collecting sample for the urine ACR. An early-morning sample is preferred. The patient should refrain from heavy exercises 24 hours before the test. A repeat test should be done 3 to 6 months after the first positive test for microalbuminuria. Lastly, the test is inaccurate in a person with very high or very low muscle mass. This is due to the variation in creatinine level which is produced by the muscle. ==References==