Post-streptococcal glomerulonephritis (GN)
Glomerulonephritis - post-streptococcal; Post-infectious glomerulonephritis
Post-streptococcal glomerulonephritis (GN) is a disorder of the kidneys that occurs after infection with certain strains of streptococcus bacteria.
Causes
Post-streptococcal 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.
Glomerulonephritis
Glomerulonephritis is a type of kidney disease in which the part of your kidneys that helps filter waste and fluids from the blood is damaged....
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.
Post-streptococcal 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, post-streptococcal GN is a rare complication of these infections.
Risk factors include:
-
Strep throat
Strep throat
Strep throat is a disease that causes a sore throat (pharyngitis). It is an infection with a germ called group A streptococcus bacteria.
- Streptococcal skin infections (such as impetigo )
Symptoms
Symptoms may include any of the following:
-
Decreased urine output
Decreased urine output
Decreased urine output means that you produce less urine than normal. Most adults make at least 500 ml of urine in 24 hours (a little over 2 cups)....
- 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
Blood in the urine
Blood in your urine is called hematuria. The amount may be very small and only detected with urine tests or under a microscope. In other cases, the...
- 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 ( auscultation ). Blood pressure is often high.
Auscultation
Auscultation is listening to the sounds of the body during a physical examination.
Other tests that may be done include:
-
Anti-DNase B
Anti-DNase B
Anti-DNase B is a blood test to look for antibodies to a substance produced by Group A Streptococcus. This is the bacteria that causes strep throat....
-
Kidney biopsy
(this is usually not needed)
Kidney biopsy
A kidney biopsy is the removal of a small piece of kidney tissue for examination.
-
Serum ASO
(and streptolysin O)
Serum ASO
Antistreptolysin O (ASO) titer is a blood test to measure antibodies against streptolysin O, a substance produced by group A streptococcus bacteria. ...
-
Serum complement levels
Serum complement levels
Complement is a blood test that measures the activity of certain proteins in the liquid portion of your blood. The complement system is a group of pr...
-
Urinalysis
Urinalysis
Urinalysis is the physical, chemical, and microscopic examination of urine. It involves a number of tests to detect and measure various compounds th...
Treatment
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.
Outlook (Prognosis)
Post-streptococcal GN usually goes away by itself after several weeks to months.
In small number of adults, it may get worse and lead to long-term (chronic) kidney failure. Sometimes, it can progress to end-stage kidney disease, which requires dialysis and a kidney transplant.
Possible Complications
Health problems that may result from this disorder include:
-
Acute renal failure
Acute renal failure
Acute kidney failure is the rapid (less than 2 days) loss of your kidneys' ability to remove waste and help balance fluids and electrolytes in your b...
- Chronic glomerulonephritis
- Chronic renal disease
-
Congestive heart failure
or
pulmonary edema
Congestive heart failure
Heart failure is a condition in which the heart is no longer able to pump oxygen-rich blood to the rest of the body efficiently. This causes symptom...
Pulmonary edema
Pulmonary edema is an abnormal buildup of fluid in the lungs. This buildup of fluid leads to shortness of breath.
-
End-stage renal disease
End-stage renal disease
End-stage kidney disease is the last stage of chronic kidney disease. This is when your kidneys can no longer support your body's needs. End-stage k...
-
Hyperkalemia
Hyperkalemia
High potassium level is a problem in which the amount of potassium in the blood is higher than normal. The medical name of this condition is hyperka...
- High blood pressure (hypertension)
-
Nephrotic syndrome
Nephrotic syndrome
Nephrotic syndrome is a group of symptoms that include protein in the urine, low blood protein levels in the blood, high cholesterol levels, high tri...
When to Contact a Medical Professional
Call your health care provider if:
- You have symptoms of post-streptococcal GN
- You have post-streptococcal GN, and you have decreased urine output or other new symptoms
Prevention
Treating known streptococcal infections may help prevent post-streptococcal GN.
References
Meyrier A. Postinfectious glomerulonephritis. In: Gilbert SJ, Weiner DE, eds. National Kidney Foundation Primer on Kidney Diseases . 6th ed. Philadelphia, PA: Elsevier Saunders; 2014:chap 22.
Pan CG, Avner ED. Glomerulonephritis associated with infections. In: Kliegman RM, Stanton BF, St. Geme, JW, Schor NF, eds. Nelson Textbook of Pediatrics. 20th ed. Philadelphia, PA: Elsevier; 2015:chap 511.
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Kidney anatomy - illustration
The kidneys are responsible for removing wastes from the body, regulating electrolyte balance and blood pressure, and stimulating red blood cell production.
Kidney anatomy
illustration
Review Date: 9/22/2015
Reviewed By: Charles Silberberg, DO, private practice specializing in nephrology, affiliated with New York Medical College, Division of Nephrology, Valhalla, NY. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team.