Definition

Glomerulonephritis is a kidney condition that involves damage to the glomeruli. Glomeruli are the tiny structures within the kidney that filter blood.

The kidneys are bean-shaped organs located in the back just below the rib cage. Each kidney is about the size of a fist. The two kidneys filter blood, catch needed substances and return them to the circulation, and dispose of wastes in the urine. If the kidneys don’t filter properly, wastes build up in the blood.

There are two types of glomerulonephritis:

• Acute glomerulonephritis begins suddenly.
• Chronic glomerulonephritis develops gradually over several years.

In some cases, glomerulonephritis leads to kidney failure. Kidney failure]]> is a severe kidney disease that must be treated with ]]>dialysis]]> or ]]>kidney transplant]]> .

Anatomy of the Kidney

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Causes

Causes of glomerulonephritis include:

• Streptococcal infection of the throat ( strep throat]]> ) or skin ( ]]>impetigo]]> )
• Hereditary diseases
• Immune diseases, such as ]]>lupus]]>
• ]]>Type 1 diabetes]]> and ]]>Type 2 diabetes]]>
• ]]>High blood pressure]]>
• Vasculitis (inflammation of the blood vessels)
• Viruses ( ]]>HIV]]> , ]]>hepatitis B virus]]> , and ]]>hepatitis C virus]]> )
• ]]>Endocarditis]]> (infection of the valves of the heart)

Risk Factors

A risk factor is something that increases your chance of getting a disease or condition.

Risk factors for glomerulonephritis include:

• Family history of glomerulonephritis
• The presence of a known cause of glomerulonephritis

Symptoms

Glomerulonephritis sometimes causes no symptoms and is discovered during a routine urine test. When present, the symptoms of acute and chronic glomerulonephritis differ from one another.

The symptoms of acute glomerulonephritis may include:

• Blood in urine (red, brown, or tea-colored urine)
• Foamy appearance of urine
• Less frequent urination
• Swelling in the morning, especially in the face, feet, hands, and abdomen

Chronic glomerulonephritis can lead to kidney failure, which may cause these symptoms:

• Feeling tired
• Dry, itchy skin
• Nausea
• Vomiting
• Poor appetite
• Muscle cramps at night
• Swelling of the face, feet, hands, or abdomen

Diagnosis

Your doctor will ask about your symptoms and medical history, and perform a physical exam. You may be referred to a doctor who specializes in kidney disease for further diagnostic testing and treatment (nephrologist).

Tests may include:

• Urinalysis—test to look for blood, protein, bacteria, and other evidence of kidney damage in the urine
• Blood tests—tests to check how well the kidneys are functioning and to look for medical conditions that may be causing glomerulonephritis
• Ultrasound]]> —a test that uses sound waves to create images of the kidneys
• ]]>Abdominal CT scan]]> —a type of x-ray test that uses a computer to create detailed images of the structures inside the abdomen, including the kidneys
• Kidney ]]>biopsy]]> —removal of a sample of kidney tissue with a needle to test for glomerulonephritis

Treatment

Treatment will depend on the underlying cause of glomerulonephritis. For example, control of blood pressure and blood sugar with medications would be important in the treatment glomerulonephritis related to hypertension and diabetes. In addition, the following steps may be taken to aid kidney function or reduce further damage:

• Diuretics to reduce fluid retention
• Medications to suppress the immune system

• Restrict salt and water intake.
• Restrict intake of potassium, phosphorous, and magnesium.
• Cut down on protein in the diet.
• Maintain a healthy weight through diet and exercise.
• Take calcium supplements.

If the kidneys are unable to remove sufficient waste from the blood, dialysis]]> may be required. Temporary dialysis may be sufficient for acute glomerulonephritis. If it leads to permanent kidney failure, chronic glomerulonephritis will require long-term dialysis or ]]>kidney transplant]]> .

Prevention

The following steps may decrease your risk of glomerulonephritis:

• Seek a doctor promptly if you have a sore throat that might be due to strep]]> .
• To reduce the risk of getting viral infections, including HIV, use safer sex practices, and avoid intravenous drug use.
• If you have diabetes or high blood pressure, see your doctor about managing these conditions.