Your body has two kidneys. Your kidneys filter your blood to remove waste and excess fluid from your body, and return blood and protein to your bloodstream. Your kidneys connect to your bladder, which holds urine. Waste and excess fluid from your kidneys exit your body through urine.
A glomerulus is a cluster of looping blood vessels in the kidneys that filters blood. More than one glomerulus is called glomeruli.
Many diseases can attack the glomeruli and damage them, and when the glomeruli are damaged, they’re unable to properly filter blood. This can lead to glomerular disease, in which excess waste and fluid stay in the bloodstream, or protein and blood leak into the urine.
There are many kinds of glomerular disease, but they fall into two main categories:
- Glomerulonephritis – Damage to the glomeruli caused by inflammation of blood vessels
- Glomerulosclerosis – Damage to the glomeruli caused by scarring or hardening of blood vessels
Causes of glomerular disease
Glomerular disease can be caused by an infection or drug that harms your kidneys or other conditions, such as lupus or diabetes. Sometimes, there’s no known reason for glomerular disease. Each main category of glomerular disease has some identifiable causes.
Glomerulonephritis
Glomerular disease due to inflammation of the blood vessels in the kidneys can be caused by:
- Diabetic kidney disease – Diabetic kidney disease is the leading cause of glomerular disease and of total kidney failure in the United States. Diabetes causes high blood sugar levels, which can damage the kidneys.
- Vasculitis – Vasculitis is an autoimmune disease that causes inflammation of blood vessels. When the blood vessels in the kidney are inflamed, it can result in damage to the kidneys.
- Lupus – Lupus is an autoimmune disease that causes antibodies to attack cells in the kidneys. Lupus causes swelling of the glomeruli, preventing them from working properly.
- Goodpasture’s syndrome – Goodpasture’s syndrome is a rare autoimmune disease that causes antibodies to attack cells in the lining of the kidneys and lungs. It typically appears in people aged 20-30, or after 60.
- Membranous nephropathy – Membranous nephropathy (MN) is an autoimmune disease that causes antibodies to attack the glomeruli, which leads to large losses of protein into the urine.
- IgA nephropathy – IgA nephropathy, also known as immunoglobulin A nephropathy, Berger’s disease and IgAN, is an autoimmune condition that damages the glomeruli inside your kidneys and can cause kidney disease.
- Infections – Bacterial and viral infections can place excess stress on the kidneys and cause damage to the glomeruli. Strep throat, bacterial endocarditis and HIV are all infections that can cause glomerular disease.
- Inherited conditions – In some cases, glomerular disease can occur due to genetic conditions. Alport syndrome, also known as hereditary nephritis, can be inherited from a parent and cause glomerular disease, among other symptoms like hearing and/or vision loss.
Glomerulosclerosis
Glomerular disease due to scarring or hardening of the blood vessels in the kidneys can be caused by:
- Diabetic kidney disease – Diabetic kidney disease is the leading cause of glomerular disease and of total kidney failure in the United States. Diabetes causes high blood sugar levels, which can damage the kidneys.
- Focal segmental glomerulosclerosis – Scarring in sporadic parts of the kidneys due to a either a specific disease or unknown cause, is known as focal segmental glomerulosclerosis (FSGS).
All kinds of glomerular disease can eventually lead to kidney failure, which would require dialysis or a kidney transplant. It’s important to seek help from your doctor early to slow the rate of damage to your kidneys.
Glomerular disease symptoms
Symptoms of glomerular disease include:
- High amounts of protein in the urine (albuminuria) – When kidneys are damaged, protein can leak through kidney tissue and exit the body in urine. High concentrations of protein in urine can cause pee to be foamy.
- Low blood protein (hypoproteinemia) – If protein leaks through the kidneys and into urine, blood will have decreased levels of protein in it.
- Blood in the urine (hematuria) – When blood leaks through the kidneys, it exits the body in the urine. Blood in the urine can cause pee to be pink or brown.
- Swelling in parts of the body (edema) – When kidneys are damaged, excess water can build up in the body. This can cause swelling in the hands, ankles or around the eyes.
- Excess waste in the blood stream – When the kidneys are damaged, waste like creatine or urea nitrogen can build up in the bloodstream.
Glomerular disease diagnosis
The most reliable way to diagnose glomerular disease is through blood and urine tests. In some cases, a kidney biopsy may be performed. The Ohio State University Wexner Medical Center in Columbus, Ohio, offers the most advanced diagnostic tools for assessing kidney diseases. Glomerular disease can be diagnosed through the following:
- Blood test – Your doctor will take a blood sample and have it analyzed for the presence of waste products, such as creatine or urea nitrogen.
- Urine test – Your doctor will ask you to provide a urine sample, which will be tested for the presence of blood and protein.
- Kidney biopsy – Your doctor will use a needle to extract a small sample of kidney tissue. The tissue will be examined under a microscope to determine if there is cellular damage.
Glomerular disease treatment
Nephrologists are doctors who focus on treating kidney diseases and conditions. At Ohio State, nephrologists and scientists partner to provide the most advanced kidney care. And, since glomerular disease has many potential causes, treatment will be individualized for each patient.
Some instances of glomerular disease, like those caused by a strep infection, may resolve on their own. Other cases that have an underlying cause, like an autoimmune disease, will require treatment. The goal of treatment is to slow damage to your kidneys and manage symptoms. Your doctor may recommend:
- Lifestyle changes – Managing your blood sugar and blood pressure through healthy eating and regular exercise can help reduce negative effects on your kidneys.
- Water pills – Water pills, also known as diuretics, help your body eliminate excess fluid. This can relieve swelling in your hands, ankles and other parts of your body caused by glomerular disease.
- Medication – Your doctor may prescribe corticosteroids or other medication to help manage your immune system.
Learn more about kidney care at Ohio State.