Management and Prognosis of Acute Post-Streptococcal Glomerulonephritis (APSGN)

Background (Brief)

Management

1. Eradication of Residual Streptococcal Infection

• If streptococcal infection is still present at the time of diagnosis, benzathine penicillin G 1.2 million units IM is administered to:
  • Treat the individual
  • Prevent spread of the nephritogenic strain to contacts
• This does NOT alter the course of the glomerulonephritis itself but is important for infection control

2. Supportive / Symptomatic Treatment

a. Control of Volume Overload (Edema / Oliguria)

• Loop diuretics (e.g., furosemide) - to manage fluid retention and reduce edema
• Salt restriction - dietary sodium restriction to reduce fluid accumulation

b. Control of Hypertension

• Antihypertensive agents as needed, guided by BP severity
• Diuretics also contribute to BP reduction via volume depletion

c. Management of Specific Complications

3. No Specific Immunosuppressive Therapy

• Steroids and immunosuppressants are not routinely used - the disease is self-limiting in the vast majority
• Renal biopsy is rarely necessary; it should be considered when there is diagnostic uncertainty or the course is atypical (e.g., absence of complement recovery, prolonged azotemia, or nephrotic syndrome without prior infection)

4. Monitoring During Recovery

• Serial urinalysis (hematuria and proteinuria resolve over weeks to months)
• Serum complement C3 levels - should normalize within 6-8 weeks; persistent low C3 beyond 8 weeks suggests an alternative diagnosis (e.g., MPGN, lupus nephritis)
• Blood pressure monitoring
• Renal function tests (BUN, creatinine)

Prognosis

In Children (Excellent)

• Short-term prognosis is excellent
• Acute symptoms (hematuria, edema, hypertension, oliguria) typically resolve within 2-7 days of supportive treatment
• Proteinuria and microscopic hematuria may persist for several months but eventually resolve
• Complete recovery of kidney function in the vast majority
• Long-term progression to end-stage renal disease (ESRD) is uncommon in the absence of other contributing factors
• Recurrence is rare (immunity develops after infection with the nephritogenic strain)

In Adults (Worse Outcomes)

• More serious morbidity can occur, partly due to preexisting cardiovascular and metabolic disease
• Greater likelihood of azotemia, heart failure, and nephrotic-range proteinuria at presentation
• Underlying kidney disease (especially diabetic nephropathy) is associated with a worse prognosis
• Risk of progression to chronic kidney disease is higher than in children

Factors Associated with Worse Prognosis

Long-Term Outlook

• Subclinical disease (microscopic hematuria + low C3 alone) - resolves completely in essentially all cases
• Clinical APSGN in children - near-complete recovery expected
• Clinical APSGN in adults with comorbidities - subset may develop chronic kidney disease or ESRD over years
• Post-streptococcal GN has been identified as a risk factor for chronic kidney disease in long-term follow-up studies, particularly in indigenous/Aboriginal populations with recurrent or severe disease

• Goldman-Cecil Medicine, Chapter 269 (Streptococcal Infections - Treatment and Prognosis of PSGN)
• Goldman-Cecil Medicine, Chapter 107 (Glomerular Disorders - Treatment and Prognosis)
• Brenner and Rector's The Kidney (long-term outcomes in adult APSGN)