What Is Glomerulonephritis?

Glomerulonephritis (pronounced: gluh-mare-you-low-neh-FRY-tis) is a kidney problem. When someone has glomerulonephritis, tiny filtering units in the kidneys called glomeruli become inflamed (swollen and irritated) and the kidneys stop working properly.

This can lead to problems like too much fluid in the body, which can cause swelling in places like the face, feet, ankles, or legs. Glomerulonephritis also can cause kidney failure and kidney disease, but that's rare.

Glomerulonephritis can be acute (meaning it comes on suddenly) or chronic (developing over several months to years). How it's treated depends on which type a person has.

The good news about glomerulonephritis is that most of the time it gets better on its own — and, if it doesn't, there's a lot that doctors can do to prevent further damage.

What Causes Glomerulonephritis?

Things that might cause acute glomerulonephritis include:

• an infection with streptococcal bacteria (the bacteria that cause strep throat)
• immunological problems (like lupus and Henoch-Schönlein purpura)

Chronic GN can be passed down in families, but sometimes doctors don't know what causes it.

What Are the Signs & Symptoms of Glomerulonephritis?

Signs of glomerulonephritis include:

• blood in the urine (red or brown pee)
• pee that might look foamy in the toilet (from too much protein)
• swelling around the face, eyes, ankles, legs, and belly, especially in the morning
• high blood pressure (hypertension)

With acute glomerulonephritis, these symptoms might come on suddenly, possibly after a skin infection or a case of strep throat. Chronic glomerulonephritis can take several months to years to develop, and a person might not notice it right away (unless a doctor tests for it).

If glomerulonephritis isn't caught early and treated, there's a chance of kidney damage or failure. Symptoms of kidney failure are:

• peeing a lot
• lower amounts of pee
• lack of appetite
• nausea and vomiting
• weight loss
• muscle cramps at night
• fatigue (tiredness)
• pale skin
• high blood pressure
• headaches
• fluid buildup in the tissues

Someone who has these symptoms might not have kidney failure — many other things can cause them. But if you notice any of these problems, see a doctor right away to find out what's going on.

How Is Glomerulonephritis Diagnosed?

If you notice swelling, blood in your urine, or any other symptoms of glomerulonephritis, talk to a parent and make an appointment to see a doctor. The doctor will ask you about your symptoms and will probably want to get urine and blood samples.

Sometimes doctors do imaging scans, like an  ultrasound , to get a better look at the kidney. In some cases, the doctor will do a kidney biopsy while the patient is asleep to take a tiny sample of kidney tissue. The tissue is sent to a lab for testing, and the results may show why there's inflammation in the kidney. These kinds of tests help doctors figure out what's going on, what type of kidney damage is there, and what treatments might help.

How Is Glomerulonephritis Treated?

Acute Glomerulonephritis

Sometimes acute glomerulonephritis gets better on its own. Treatment, if needed, depends on the cause and a person's age and overall health.

When an immune system problem causes GN, doctors prescribe steroids and other drugs that help suppress the immune system. Antibiotics can treat a bacterial infection. Some people may need a treatment to clean the blood using an artificial filter, called dialysis, if their kidneys are greatly and irreversibly damaged.

To deal with uncomfortable symptoms, doctors may give medicines to lower blood pressure or help the kidneys make pee and get rid of waste. A person might need to drink less fluids than usual and eat a diet that's low in protein, salt, and potassium.

In most cases of acute GN, the damage to the glomeruli eventually heals. How long this takes is different for everyone. Acute GN that doesn't respond to treatment can become chronic.

Chronic Glomerulonephritis

There's no specific way to treat chronic glomerulonephritis. To help healing and prevent more damage to the kidneys, a doctor might recommend that someone:

• eat a healthy diet with less protein, potassium, phosphorus, and salt
• get plenty of exercise (at least 1 hour a day)
• drink less fluids
• take calcium supplements
• take medicines to lower high blood pressure

When these methods don't help enough to prevent lasting kidney damage, a person may need dialysis treatments or a kidney transplant. But most teens with glomerulonephritis don't need these procedures, and can continue to take part in sports or other activities and live life just like other teens.