Poststreptococcal glomerulonephritis (GN)
Poststreptococcal glomerulonephritis (GN) is a disorder of the kidneys that occurs after infection with certain strains of streptococcus bacteria.
Glomerulonephritis - poststreptococcal; Postinfectious glomerulonephritis
Poststreptococcal GN is a form of glomerulonephritis. It is caused by an infection with a type of streptococcus bacteria. The infection does not occur in the kidneys, but in a different part of the body, such as the skin or throat.
The strep bacterial infection causes the tiny blood vessels in the filtering units of the kidneys (glomeruli) to become inflamed. This makes the kidneys less able to filter the urine.
Poststreptococcal GN is uncommon today because infections that can lead to the disorder are commonly treated with antibiotics. The disorder may develop 1 to 2 weeks after an untreated throat infection, or 3 to 4 weeks after a skin infection.
It may occur in people of any age, but it most often occurs in children ages 6 through 10. Although skin and throat infections are common in children, poststreptococcal GN is a rare complication of these infections.
Risk factors include:
Symptoms may include any of the following:
- Decreased urine output
- Rust-colored urine
- Swelling (edema), general swelling, swelling of the abdomen, swelling of the face or eyes, swelling of the feet, ankles, hands
- Visible blood in the urine
- Joint pain
- Joint stiffness or swelling
Exams and Tests
A physical examination shows swelling (edema), especially in the face. Abnormal sounds may be heard when listening to the heart and lungs with a stethoscope. Blood pressure is often high.
Other tests that may be done include:
- Anti-DNase B
- Serum ASO (and streptolysin O)
- Serum complement levels
- Kidney biopsy (usually not needed)
There is no specific treatment for this disorder. Treatment is focused on relieving symptoms.
- Antibiotics, such as penicillin, will likely be used to destroy any streptococcal bacteria that remain in the body.
- Blood pressure medicines and diuretic drugs may be needed to control swelling and high blood pressure.
- Corticosteroids and other anti-inflammatory medicines are generally not effective.
You may need to limit salt in the diet to control swelling and high blood pressure.
Poststreptococcal GN usually goes away by itself after several weeks to months.
Health problems that may result from this disorder include:
- Acute renal failure (rapid loss of kidneys' ability to remove waste and help balance fluids and electrolytes in the body)
- Chronic glomerulonephritis
- Chronic kidney disease
- Heart failure or pulmonary edema (fluid buildup in the lungs)
- End-stage renal disease
- Hyperkalemia (abnormally high potassium level in the blood)
- High blood pressure (hypertension)
- Nephrotic syndrome (group of symptoms that include protein in the urine, low blood protein levels in the blood, high cholesterol levels, high triglyceride levels, and swelling)
When to Contact a Medical Professional
Call your health care provider if:
- You have symptoms of poststreptococcal GN
- You have poststreptococcal GN, and you have decreased urine output or other new symptoms
Treating known streptococcal infections may help prevent poststreptococcal GN.
Kliegman RM, Stanton BF, St. Geme JW, Schor NF. Glomerulonephritis associated with infections. In: Kliegman RM, Stanton BF, St. Geme JW, Schor NF, eds. Nelson Textbook of Pediatrics. 20th ed. Philadelphia, PA: Elsevier; 2016:chap 511.
Pendergraft WF, Nachman PH, Jennette JC, Falk RJ. Primary glomerular disease. In: Skorecki K, Chertow GM, Marsden PA, Taal MW, Yu ASL, eds. Brenner and Rector's The Kidney. 10th ed. Philadelphia, PA: Elsevier; 2016:chap 32.