Acute poststreptococcal glomerulonephritis

Acute poststreptococcal glomerulonephritis: Excerpt from Professional Guide to Diseases (Eighth Edition)

Acute poststreptococcal glomerulonephritis (APSGN), also known as acute glomerulonephritis, is a relatively common bilateral inflammation of the glomeruli. It usually follows a streptococcal infection of the respiratory tract or, less often, a skin infection such as impetigo.

Causes and incidence

APSGN results from the entrapment and collection of antigen-antibody (produced as an immunologic mechanism in response to streptococcus) in the glomerular capillary membranes, inducing inflammatory damage and impeding glomerular function. Sometimes, the immune complement further damages the glomerular membrane. The damaged and inflamed glomerulus loses the ability to be selectively permeable, and allows red blood cells (RBCs) and proteins to filter through as the glomerular filtration rate (GFR) falls. Uremic poisoning may result.

APSGN is most common in males ages 3 to 7, but it can occur at any age. Incidence is rising in the United States and Europe, with epidemics occurring in developing countries in Africa, the West Indies, and the Middle East.

Up to 95% of children and up to 70% of adults with APSGN recover fully; the rest may progress to chronic renal failure within months.

Signs and symptoms

APSGN begins within 1 to 3 weeks after untreated pharyngitis. Symptoms include mild to moderate edema, oliguria (less than 400 ml/24 hours), proteinuria, azotemia, hematuria, and fatigue. Mild to severe hypertension may result from either sodium or water retention (due to decreased GFR) or inappropriate renin release. Heart failure from hypervolemia leads to pulmonary edema.

PEDIATRIC TIP The presenting features of APSGN in children may be encephalopathy with seizures and focal neurological deficits.

Diagnosis

Diagnosis requires a detailed patient history and assessment of clinical symptoms and laboratory tests.

Urinalysis typically reveals proteinuria and hematuria. RBCs, white blood cells, and mixed cell casts are common in urinary sediment. Elevated serum creatinine levels and low creatinine clearance accompany impaired glomerular filtration. Elevated antistreptolysin-O titers (in 80% of patients), elevated streptozyme and anti-DNase B titers, and low serum complement levels verify recent streptococcal infection. A throat culture may also show group A beta-hemolytic streptococcus. Renal ultrasound may show a normal or slightly enlarged kidney. A renal biopsy may confirm the diagnosis or assess renal tissue status.

Treatment

The goals of treatment are relief of symptoms and prevention of complications. Vigorous supportive care includes bed rest, fluid and dietary sodium restrictions, and correction of electrolyte imbalances (possibly with dialysis, although this is rarely necessary). Therapy may include diuretics to reduce extracellular fluid overload and an antihypertensive. The use of antibiotics is recommended for 7 to 10 days if staphylococcal infection is documented. Otherwise, antibiotic use is controversial.

Special considerations

APSGN usually resolves within 2 weeks, so patient care is primarily supportive.

❑ Check vital signs and electrolyte values. Monitor intake and output and daily weight. Assess renal function daily through serum creatinine, blood urea nitrogen, and urine creatinine clearance levels. Watch for and immediately report signs of acute renal failure (oliguria, azotemia, and acidosis).

❑ Consult the dietitian to provide a diet high in calories and low in protein, sodium, potassium, and fluids.

❑ Protect the debilitated patient against secondary infection by providing good nutrition, using good hygienic technique, and preventing contact with infected persons.

❑ Bed rest is necessary during the acute phase. Allow the patient to gradually resume normal activities as symptoms subside.

❑ Provide emotional support for the patient and his family. If the patient is on dialysis, explain the procedure fully.

❑ Advise the patient with a history of chronic upper respiratory tract infections to immediately report signs of infection (fever, sore throat).

❑ Tell the patient that follow-up examinations are necessary to detect chronic renal failure. Stress the need for regular blood pressure, urinary protein, and renal function assessments during the convalescent months to detect recurrence. After APSGN, gross hematuria may recur during nonspecific viral infections; abnormal urinary findings may persist for years.

❑ Encourage pregnant females with a history of APSGN to have frequent medical evaluations because pregnancy further stresses the kidneys and increases the risk of chronic renal failure.

Book Source Details

• Book Title: Professional Guide to Diseases (Eighth Edition)
• Author(s): Springhouse
• Year of Publication: 2005
• Copyright Details: Professional Guide to Diseases (Eighth Edition), Copyright © 2005 Lippincott Williams & Wilkins.

More About Wegener's granulomatosis

• Back to disease: Wegener's granulomatosis: Introduction
• Next Book Extract About Wegener's granulomatosis: Acute respiratory distress syndrome (Professional Guide to Diseases (Eighth Edition))
• More Book Extracts: All Online Books for Wegener's granulomatosis

More Medical Textbooks Online about Wegener's granulomatosis

Review other book chapters online related to Wegener's granulomatosis:

Copyright notice for book excerpts: Copyright © 2008 Lippincott Williams & Wilkins. All rights reserved.

More About This Book: Title: Professional Guide to Diseases (Eighth Edition) Authors: Springhouse Publisher: Lippincott Williams & Wilkins Copyright: 2005 ISBN: 1-58255-370-X

 » Next page: Acute respiratory distress syndrome (Professional Guide to Diseases (Eighth Edition))

Rate This Website

What do you think about the features of this website? Take our user survey and have your say:

Website User Survey

Medical Tools & Articles:

Next articles:

• Acute respiratory distress syndrome (Professional Guide to Diseases (Eighth Edition))
• Acute respiratory failure (Professional Guide to Diseases (Eighth Edition))
• Respiratory alkalosis (Professional Guide to Diseases (Eighth Edition))
• Respiratory syncytial virus infection (Professional Guide to Diseases (Eighth Edition))
• Chronic glomerulonephritis (Professional Guide to Diseases (Eighth Edition))

Tools & Services:

• Bookmark this page
• Symptom Search
• Symptom Checker
• Medical Dictionary
• Give your feedback

Medical Articles:

• Disease & Treatments Search
• Misdiagnosis Center
• Full list of interesting articles

Forums & Message Boards

• Ask or answer a question at the Boards:
• I cannot get a diagnosis. Please help.
• Tell us your medical story.
• Share your misdiagnosis story.
• What is the best treatment for my condition?
• See all the Boards.

Enter your search terms Submit search form
Search The Web Search wrongdiagnosis.com

Common Health Mistakes

Symptom
Checker

Search Specialists by State and City