Does Microalbuminuria Predict Diabetic Nephropathy?

Diabetes is a common disease, which may afflict children as well as adults. Before attempting to comprehend its related complications, it is very important to understand its types and their origin.

Type 1 diabetes is generally called the juvenile onset diabetes. In this health condition, the body’s defence system attacks the cells that produce insulin hormone. It is a kind of an auto-immune response. This type of diabetes generally occurs in children or young adults and requires regular insulin injections.

[Read: Diagnosis of Diabetic Ketoacidosis]

Type 2 diabetes is the adult-onset diabetes, also known as non-insulin dependent diabetes. It is characterised by insulin deficiency or insulin resistance. This type of diabetes is often related to obesity, which itself is a cause of insulin resistance and can lead to high blood glucose levels.

Diabetes very often leads to other complications like retinopathy(blurry vision), heart stroke, foot complications, skin infections and kidney problems. 40 out of every 100 people with diabetes face the problems like kidney damage, high cholesterol and high blood pressure. Also, African- Americans, Native Americans and Hispanics are at a higher risk of getting affected with diabetes.

What is Nephropathy?

Itis a kidney damage or disease. During diabetic nephropathy (DN), diabetes causes damage to the kidneys, leading to leakage of albumin (protein) in the urine. According to the National Kidney Foundation, small injured blood vessels in the body can result in diabetic kidney disease. When the small blood vessels (caused by high blood sugar levels in diabetes) of the kidney are injured, the kidney is no longer capable of cleaning the blood properly. As a result, the body retains more salt and water, leading to weight gain and ankle swelling.

[Read: What is Diabetes kidney?]

What is Microalbuminuria?

It is the condition when 30 to 300mg of albumin is excreted in the urine in a day. Less than 30mg is too insignificant to worry about, but more than 300 mg is termed as macroalbuminura. For the diagnosis, the National Institute for Health and Clinical Excellence Guidance recommends that an early morning urinary ratio of albumin creatinine (ACR) should be done rather than any other test of proteinuria. ACR offers more sensitivity to lower levels of proteinuria than any other test and is also more convenient than the traditional 24-hour collection.

A study was conducted on 23 diabetic patients with microalbuminuria (MA) and 209 diabetic patients without MA at University of Michigan Medical Centre in 1989 and 1990. Both the groups were examined at the beginning and after 7 years the results showed that microalbuminuria regressed in 56% of the patients without any corrective measures being applied. 16% of the subjects without initial MA developed it.

This study concluded that microalbuminuria may not be very sensitive and specific as a predictor of diabetic nephropathy. In spite of the above study, MA is considered a huge risk factor for progressive renal deficiency in diabetes and also diabetic nephropathy. If the factors cause the change from normal excretion of albumin in the urine to microalbuminuria and then from MA to diabetic nephropathy could be identified, primary prevention of diabetic nephropathy is possible. When studies were conducted on type 1 and type 2 diabetic patients, risk factors associated with microalbuminuria and its progression to diabetic nephropathy could be identified. These include hypertension (including family history of hypertension), lower BMI, dyslipidaemia, cigarette smoking and a long duration of diabetes.

[Read: Prognosis of Diabetic Nephropathy]

How to detect Diabetic Nephropathy?

A protein called albumin is checked for in the urine. Generally, protein is not found in the urine, but in case of kidney damage, the kidneys become incapable of filtering out the protein and it may leak into the urine.

People with diabetes must have regular checks as early detection can prevent more damage. In case of patients with type 1 diabetes, a urine test every year is a must after 5 years of having diabetes. In case of type 2 diabetes, yearly tests should be done as soon as diabetes is diagnosed.

So, in conclusion, microalbuminuria does seem to predict diabetic nephropathy or at least is an indicator. Levels of albumin in the urine may be due to some other causes, but kidney damage due to diabetes cannot be ruled out. Conclusive tests must be done to ascertain and treat the condition.


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