Microalbuminuria is a condition where the urine contains abnormally high levels of dissolved proteins, the National Kidney Foundation explains. In microalbuminuria, the protein levels are only slightly above normal, and higher levels are referred to as macroalbuminuria.
Persistently high levels of protein in the urine indicate kidney damage, which causes the kidneys to leak albumin into the urine, states the National Kidney Foundation. Possible causes include metabolic syndrome, nephrotic syndrome, congestive heart failure or high blood pressure. In patients with known kidney problems, microalbuminuria can indicate that the kidney problems are more likely to worsen and lead to kidney failure. Because it can be a first sign of several conditions that require treatment, regular testing for albuminuria is recommended for people at risk for these conditions.
Microalbuminuria can also be caused by less serious conditions, such as recent heavy exercise, smoking, urinary tract infections and other illnesses, says the National Kidney Foundation. One of the more serious and common conditions to cause microalbuminuria, however, is diabetic kidney disease. Diabetic kidney disease is one of the most serious common complications of diabetes. Over several years, it can lead to scarring of the kidneys until they can no longer function at all, and it necessitates dialysis or kidney transplant.