The kidneys contain many coils of tiny blood vessels. Each of these is called a glomerulus. Glomeruli filter substances from the blood into the urine. Glomerulonephritis is a type of kidney disease where these coils become inflamed. This makes it hard for the kidneys to filter the blood.

Glomerulonephritis can be caused by diseases such as:

• Systemic autoimmune diseases. With these types of diseases, the body's immune system attacks healthy cells by mistake. Systemic means that many parts of the body are affected. An example of this is systemic lupus erythematosus (SLE or lupus).
• Polyarteritis nodosa. This is an inflammatory disease of the arteries.
• Granulomatosis with polyangiitis. This is a progressive disease that leads to widespread inflammation of all of the body's organs.
• Henoch-Schönlein purpura. This disease causes small or large purple lesions (purpura) on the skin and internal organs. It causes other symptoms in several organ systems.
• Alport syndrome. This is a form of inherited glomerulonephritis that affects both boys and girls. But boys are more likely to have kidney problems. Treatment focuses on preventing and treating high blood pressure and preventing kidney damage.
• Streptococcal infection. In children, glomerulonephritis is often caused by strep throat or an upper respiratory infection. The disease usually occurs 1 week or more after an infection.
• Hepatitis B. This infection can be passed from parent to baby during childbirth or, rarely, contracted through a blood transfusion.

A child is more at risk for glomerulonephritis if they have:

• A systemic autoimmune disease such as lupus.
• Polyarteritis nodosa.
• Granulomatosis with polyangiitis.
• Henoch-Schönlein purpura.
• Alport syndrome.
• A streptococcal infection.

Symptoms can be a bit different for each child. They can include:

• Urine that is dark brown, from blood and protein
• Sore throat
• Less urine
• Lack of energy or tiring easily (fatigue)
• Trouble breathing
• Headache
• High blood pressure
• Seizures from high blood pressure
• Rash, especially over the buttocks and legs
• Weight loss
• Joint pain
• Pale skin color
• Fluid buildup in the tissues (edema)

The symptoms of glomerulonephritis can be like other health conditions. Make sure your child sees their doctor for a diagnosis.

The doctor will ask about your child's symptoms and health history. They may also ask about your family's health history. They will give your child a physical exam. Your child may also have tests, such as:

• Throat culture. This may be done to check for strep throat. A swab is gently wiped in your child's throat to collect bacteria.
• Blood tests. These look at blood cell counts, electrolyte levels, and kidney function.
• Urine test. This test looks for protein and blood in urine and other problems.
• Electrocardiogram (ECG). This is a test that records the electrical activity of the heart, shows abnormal heart rhythms, and detects heart muscle damage.
• Renal ultrasound (sonography). This is a painless test that uses sound waves and a computer to create images of body tissues. During the test, a doctor moves a device called a transducer over the belly in the kidney area. This sends a picture of the kidney to a video screen. The doctor can see the size and shape of the kidney. They can also see a growth, kidney stone, cyst, or other problems.
• Chest X-ray. This test uses a small amount of radiation to make images of tissues, bones, and organs on film.
• Renal biopsy. The doctor takes a small sample of kidney tissue. This is done through the skin with a needle or during surgery. The sample is looked at under a microscope.

Most children with kidney disease see both a pediatrician or family doctor and a nephrologist. A nephrologist is a healthcare provider with special training to treat kidney problems.

Treatment will depend on your child's symptoms, age, and general health. It will also depend on the severity of the condition and the cause. Treatments focus on slowing the progression of the disease and preventing complications.

Treatment may include changes to your child's diet. Your child may need to limit:

• Protein. Protein is vital for correct growth and nutrition. But the kidneys may not be able to get rid of the waste products that come from eating too much protein. Your child's doctor will talk with you about how much protein your child needs.
• Potassium. Potassium is an important nutrient. But when the kidneys don't work well, too much potassium can build up in the blood. Potassium comes from certain foods. Your child may need to limit or not eat foods with a lot of potassium.
• Phosphorus. The kidneys help remove excess phosphorus from the body. If the kidneys are not working well, too much phosphorus builds up in the blood and can cause calcium to leave the bones. This can make your child's bones weak and easy to break. Your child may need to limit foods with phosphorus.
• Sodium. A low-sodium diet can help prevent or reduce fluid retention in your child's body. The healthcare provider will talk with you about the amount of sodium allowed in your child's diet.

Treatment may include medicines to:

• Increase urination (diuretic).
• Reduce blood pressure.
• Lower the amount of the mineral phosphorus in the blood (phosphate binders).
• Lessen the body's immune system response (immunosuppressive medicine).

In some cases, a child may develop severe problems with electrolytes. This may cause dangerous levels of waste products in the blood that are normally removed by the kidneys. A child may also develop fluid overload. A child may need dialysis in these cases.

Dialysis is a procedure that filters waste and extra fluid from the blood. This is normally done by the kidneys. There are two types of dialysis.

This can be done at home. This method uses the lining of the belly (abdominal) cavity to filter the blood. This cavity is the space that holds organs such as the stomach, intestines, and liver. The lining is called the peritoneum.

First, a surgeon places a thin, flexible tube (catheter) into your child's belly. After the tube is placed, a sterile cleansing fluid (dialysate) is put through the catheter into the peritoneal cavity. The fluid is left in the belly for a period of time. This fluid absorbs the waste products through the peritoneum. The fluid is then drained from the belly, measured, and discarded. This process of filling and draining fluid is called an exchange.

This is done in a dialysis center or hospital by health care providers. A special type of access, called an arteriovenous (AV) fistula, is placed during a small surgery. This fistula is an artery and a vein that are joined together. It is usually done in your child's arm. An external I.V. (intravenous) catheter may also be inserted. This is less common for long-term dialysis.

Your child will then be connected to a large hemodialysis machine. Blood is pumped through a tube into the machine to filter out the wastes and extra fluid. The filtered blood then flows through another tube back into your child's body.

Hemodialysis is usually done several times a week. Each session lasts for 4 to 5 hours. It may be helpful to bring games or reading materials for your child to keep them busy during this procedure.

Talk with your child's health care providers about the risks, benefits, and possible side effects of all treatments.

If glomerulonephritis does not go away, it may lead to kidney failure.

Contact the doctor if your child has:

• Symptoms that don't get better, or get worse.
• New symptoms.

• The kidneys contain many tiny coils of blood vessels called glomeruli. Glomerulonephritis is a type of kidney disease where these become inflamed. The disease makes it hard for the kidneys to filter the blood.
• The condition has many possible causes, such as an autoimmune disease or an infection.
• Symptoms can include dark brown urine, less urine, and low energy.
• Treatment may include changes in diet, medicines, or dialysis.
• If glomerulonephritis does not go away, it may lead to kidney failure.

Tips to help you get the most from a visit to your child's doctor:

• Know the reason for the visit and what you want to happen.
• Before your visit, write down questions you want answered.
• At the visit, write down the name of a new diagnosis and any new medicines, treatments, or tests. Also write down any new instructions your doctor gives you for your child.
• Know why a new medicine or treatment is prescribed and how it will help your child. Also know what the side effects are and when they should be reported.
• Ask if your child's condition can be treated in other ways.
• Know why a test or procedure is recommended and what the results could mean.
• Know what to expect if your child does not take the medicine or have the test or procedure.
• If your child has a follow-up appointment, write down the date, time, and purpose for that visit.
• Know how you can contact your child's doctor after office hours, including weekends and holidays. This is important if your child becomes ill and you have questions or need advice.