The kidneys remove toxins from our bodies using tiny structures called nephrons. Each nephron contains a cluster of blood vessels called a “glomerulus” that functions as a filter, separating excess waste, fluid, and electrolytes from your blood. 

In rare cases, these blood vessels can be damaged by a variety of causes, including genetic conditions, infection, and medications. This disrupts the kidneys’ ability to remove waste, which can lead to other complications such as high blood pressure or kidney failure. This problem is called glomerulonephritis, which although rare, can be very serious.

“Treatment for glomerulonephritis needs to be started very early,” says Jeffrey Turner, MD, a nephrologist at Yale Medicine. “It should be on the top of the list of conditions a doctor should rule out if they’re looking at a patient with similar symptoms.” 

Common symptoms of this condition include blood in the urine, rash, joint pains, and difficulty breathing. Blood tests typically show an issue with kidney function. 

In very severe cases of glomerulonephritis, the kidneys can decline very quickly and the patient might show symptoms of kidney failure such as swelling (often in legs), high blood pressure, and reduced urine.  

The exact cause of this condition is not always known, but the current consensus is that an inciting event triggers an immune response in the body that sets off a chain of responses, causing inflammation of the glomeruli. Some of the known inciting events include infections such as strep throat or impetigo. Other infections that may cause glomerulonephritis include HIV and hepatitis B. Autoimmune diseases such as lupus may also cause inflammation of the glomeruli.

In some cases, glomerulonephritis is caused by an inherited condition such as Alport syndrome, which is a condition that causes kidney disease, hearing loss, and eye abnormalities.

If your doctor suspects that you have glomerulonephritis, he or she will order tests that examine your urine to see if there is a high concentration of protein or inflammatory cells. Also, elevated levels of red and white blood cells in the urine are typical of glomerulonephritis, and this is a significant clue to making the diagnosis. In addition to the urine tests, your doctor may also order certain blood tests to look for markers that indicate glomerulonephritis. 

A kidney biopsy is typically performed to confirm the diagnosis, says Dr. Turner. Particular patterns within the tissues are what doctors are looking for; these show that the kidneys have been invaded by inflammatory blood cells. 

For severe cases, it’s important to treat this condition aggressively with steroids, biologic drugs, or chemotherapy agents. Which medication is best for a particular patient depends on a number of factors including how severe the disease is and what caused it. When an infection triggers glomerulonephritis, the primary therapy focuses on treatment of the infection, rather than with drugs that suppress the immune system.

For a mild case of glomerulonephritis, your doctor may only prescribe blood pressure medication to reduce pressure and damage of the arteries in the kidneys and glomerulus. They will then closely monitor the disease activity. 

Because this condition can lead to kidney failure, it’s crucial to treat it as quickly as possible. Once the kidneys fail, the patient will have to go on dialysis, which is a treatment that filters blood externally through a machine. “Every day that goes by increases the patient’s risk of needing dialysis,” says Dr. Turner. 

Yale Medicine is home to a dedicated glomerulonephritis clinic. Physicians in this clinic collaborate closely with rheumatologists and gather monthly to discuss rare and difficult-to-treat cases.

In addition, researchers in the department of nephrology are investigating underlying conditions that may affect the glomerulus, genetic testing for glomerulonephritis, and clinical trials for new drugs. This research not only gives our doctors more comprehensive and in-depth expertise about the disease, but also gives our patients access to treatments that are not yet available to the general public.