What is the treatment for post-infective glomerulonephritis?

Treatment for Post-Infective Glomerulonephritis

The treatment of post-infective glomerulonephritis centers on antibiotic therapy to reduce antigenic load combined with supportive management of nephritic syndrome, with immunosuppression reserved only for severe crescentic disease. 1

Antibiotic Therapy

Administer penicillin (or erythromycin if penicillin-allergic) even when active infection is no longer present to decrease the streptococcal antigenic load—this applies to classic post-streptococcal glomerulonephritis occurring 1-3 weeks after pharyngitis or impetigo. 2, 1

Alternative Antibiotic Options:

• First-generation cephalosporins (e.g., cephalexin) are appropriate for non-anaphylactic penicillin allergies or when beta-lactamase producing organisms are suspected. 2, 1
• Third-generation cephalosporins (e.g., ceftriaxone) should be used for severe infections or in areas with high prevalence of resistant organisms. 2, 1
• During outbreaks, systemic antimicrobials help eliminate nephritogenic strains of Streptococcus pyogenes from the community. 2

Special Consideration for Non-Streptococcal Infections:

• For endocarditis-related glomerulonephritis (increasingly caused by staphylococcal species), antibiotic treatment must continue for 4-6 weeks, though hematuria, proteinuria, and azotemia may persist for months after infection eradication. 1

Supportive Management of Nephritic Syndrome

Managing the clinical manifestations of acute glomerulonephritis is the cornerstone of treatment. 1

Fluid and Blood Pressure Management:

• Restrict dietary sodium to <2.0 g/day to control hypertension and fluid retention. 2, 1
• Use diuretics as first-line agents for managing fluid overload and hypertension. 2, 1
• Target blood pressure <130/80 mmHg (or <125/75 mmHg if proteinuria >1 g/day). 1
• Monitor closely for diuretic-related complications including hyponatremia, hypokalemia, GFR reduction, and volume depletion. 2, 1
• Provide dialysis if necessary for severe acute kidney injury. 2

Metabolic Management:

• Treat metabolic acidosis if serum bicarbonate <22 mmol/L. 1
• Consider treating dyslipidemia in patients with nephrotic syndrome, particularly those with other cardiovascular risk factors. 2

Immunosuppressive Therapy

Corticosteroids should be considered ONLY for severe crescentic glomerulonephritis with rapidly progressive renal failure, based on anecdotal evidence with weak evidence quality. 2, 1

Critical Caveat:

• Do NOT use corticosteroids for IgA-dominant post-infectious glomerulonephritis, which typically occurs with staphylococcal infections (including MRSA), particularly in elderly and diabetic patients. 1

Monitoring and Follow-Up

Complement Monitoring:

• Assess C3 complement levels at diagnosis and follow serially—C3 should normalize within 8-12 weeks in uncomplicated cases. 2, 1
• If C3 remains low beyond 12 weeks, perform kidney biopsy to exclude complement C3 glomerulonephritis (C3GN). 2, 1

Ongoing Assessment:

• Monitor kidney function, blood pressure, proteinuria, and hematuria regularly throughout the disease course. 2, 1

Prognosis

Post-infectious glomerulonephritis resolves completely and spontaneously in most children, with typically good long-term outcomes, preserved renal function, and no recurrence. 3 However, sporadic cases in adults, particularly those with comorbidities such as diabetes and alcoholism, may have poorer long-term outcomes. 4