- Indicator of kidney damage and / or a biomarker of systemic diseases dates back to 1969, when elevated albumin levels were first demonstrated in the urine of patients with newly diagnosed diabetes.
- Urine dipstick is a relatively insensitive marker for albuminuria, not becoming positive until albumin excretion exceeds 300-500 mg/day.
- Normal rate of albumin excretion is < 30 mg/day (20 mcg/min).
- Persistent albumin excretion between 30-300 mg/day (20 to 200 mcg/min) is called moderately increased albuminuria (formerly called "microalbuminuria").
- Excretion > 300 mg/day (200 mcg/min) represents overt or dipstick positive proteinuria (severely increased albuminuria [formerly called "macroalbuminuria"].
- Albuminuria reflects functional and / or structural changes in the glomerular filtration membrane that allow increased leakage of albumin into primary urine in amounts exceeding the reabsorption capacity of the proximal nephron tubules.
- Albuminuria considered as an indicator of early damage (dysfunction) of the vascular endothelium (including the glomerular vessels), which leads to increased permeability of the vascular wall.
- Relationship between albuminuria and cardiovascular risk has been shown in studies of the general population.
- It is linear and risk is independent of eGFR.
- Associated with arterial stiffness assessed by the pulse wave velocity measurement
