Glomerulosclerosis

Glomerulosclerosis refers to scarring or hardening of the glomeruli -- blood vessels located in the kidneys. The glomeruli filter the blood as it passes through the kidneys. They remove waste fluids that then leave the body as urine.

Damaged glomeruli can't perform their job adequately. As a result, large amounts of protein from the blood leak into the urine rather than remaining in the bloodstream. This leads to a condition called proteinuria.

Glomerulosclerosis can affect children and adults. Men are slightly more likely to develop it. African-Americans are at higher risk than whites.

Causes of Glomerulosclerosis

Focal segmental glomerulosclerosis (FSGS) is a kidney disease that can lead to glomerulosclerosis. In FSGS, the scarring occurs only in some of the glomeruli. And only part of the individual glomeruli is damaged.

Untreated, it can lead to kidney failure. In some cases, kidney failure can occur despite treatment.

FSGS most frequently occurs without a cause. In such cases it is called idiopathic or primary FSGS. Sometimes, though, FSGS does have a known cause, and these can include:

• HIV infection
• Obesity
• Sickle cell disease
• Birth defects of the kidneys
• Heroin or other drug use
• Genetic causes (in rare cases)

Besides FSGS, glomerulosclerosis can be caused by these diseases:

• Diabetes
• Lupus
• HIV infection
• Sickle cell disease

Conditions that damage the kidneys can also lead to glomerulosclerosis. These include:

• Glomerulonephritis, which causes the glomeruli to become inflamed.
• Reflux nephropathy, in which urine flows back into the kidney.

Chemicals and medicines that harm the kidneys can also cause glomerulosclerosis.

Symptoms of Glomerulosclerosis

At first, there are no obvious signs of glomerulosclerosis. Over time, symptoms can develop. These include:

Swelling. Because of fluid retention, you may have swelling in various parts of the body, including:

• Hands
• Feet
• Legs
• Abdomen
• Around the eyes

The swelling may be painful. It may also cause rapid weight gain.

Changes in urine. You may have foamy or bubbly urine, caused by proteinuria.

Often, glomerulosclerosis is discovered during a routine checkup. Tests during a checkup can reveal an abnormally high protein content in the urine (proteinuria). Or they may show a low level of protein in the blood (hypoproteinemia).

Symptoms that often accompany glomerulosclerosis include:

• High blood pressure
• High cholesterol

In glomerulosclerosis patients, high blood pressure can be difficult to control.

Diagnosis of Glomerulosclerosis

The only way you can be certain of an accurate diagnosis of glomerulosclerosis is to get a kidney biopsy. That's because the symptoms of glomerulosclerosis can also occur in many other conditions.

In a kidney biopsy, your doctor removes a very small amount of kidney tissue. The tissue is examined for signs of scarring.

Diagnosing glomerulosclerosis may require multiple biopsies. That's because the scarring does not occur throughout the kidney. So your doctor may have to look at samples from several different parts of the kidney until an affected area is found.

Other tests that may be ordered include:

• Glomerular filtration rate (measures kidney function)
• Kidney ultrasound
• Genetic testing