What is the treatment for acute glomerulonephritis?

Treatment of Acute Glomerulonephritis

Treatment of acute glomerulonephritis is primarily supportive, focusing on managing hypertension, edema, and fluid overload with diuretics and antihypertensives, while addressing the underlying cause when identified. 1

Initial Management Approach

The treatment strategy depends on the specific type and severity of acute glomerulonephritis, with the intensity of therapy predicated on presenting symptoms and degree of renal impairment 1.

Supportive Care Measures

Blood Pressure Control:

• Use ACE inhibitors or ARBs at maximally tolerated doses as first-line therapy for patients with hypertension 1, 2
• Target systolic blood pressure <120 mmHg in adults using standardized office measurement 1, 3
• In children, target 24-hour mean arterial pressure at ≤50th percentile for age, sex, and height 1, 3
• ACE inhibitors (captopril, enalapril) provide superior blood pressure control compared to other antihypertensives in acute settings 4

Edema and Fluid Management:

• Restrict dietary sodium to <2.0 g/day (<90 mmol/day) 1, 2, 3
• Use diuretics as first-line agents for edema management 1, 2, 3
• Add mechanistically different diuretics if initial response is insufficient 1, 2
• Monitor closely for hyponatremia, hypokalemia, GFR reduction, and volume depletion 1, 2
• Hold RAS inhibitors and diuretics during intercurrent illnesses with risk of volume depletion 1, 2

Dietary Modifications:

• Restrict protein intake to 0.8-1 g/kg/day in nephrotic-range proteinuria 1, 2
• Target caloric intake of 35 kcal/kg/day (30-35 kcal/kg/day if eGFR <60 ml/min/1.73 m²) 1, 2
• Avoid protein restriction <0.6 g/kg/day due to malnutrition risk 1, 2, 3

Etiology-Specific Treatment

Post-Streptococcal Glomerulonephritis

Antibiotic Therapy:

• Treat with penicillin (or erythromycin if penicillin-allergic) even in the absence of persistent infection to decrease antigenic load 1, 5
• No advantage of newer antimicrobials (cefuroxime, ceftibuten) over penicillin V for 10 days 4

Prognosis and Monitoring:

• The disease is self-limited with excellent prognosis in children, typically resolving over weeks to months 1, 5, 6, 7
• Persistently low C3 beyond 12 weeks warrants kidney biopsy to exclude C3 glomerulonephritis 1
• Adults have higher incidence of hypertension and chronic renal failure as sequelae 7

Infection-Related Glomerulonephritis (Non-Streptococcal)

• Treat the underlying infection appropriately with targeted antibiotics 1
• IgA-dominant infection-related GN has poor prognosis with dialysis frequently required and <20% returning to premorbid kidney function 1
• Avoid corticosteroids in bacterial infection-related GN due to substantial infection risks, particularly in elderly patients 1

Rapidly Progressive Glomerulonephritis (RPGN)

Immunosuppressive Therapy:

• For crescentic GN with extensive crescent formation (>50% of glomeruli), use cyclophosphamide and glucocorticoids 1, 5, 8
• High-dose corticosteroids combined with cyclophosphamide or plasma exchange for severe cases 8
• Evidence for immunosuppression in crescentic post-streptococcal GN is weak, showing no clear advantage over supportive therapy alone 4

Monitoring and Follow-Up

Laboratory Assessment:

• Assess proteinuria regularly as a marker of treatment response 1, 2, 3
• Monitor for ≥40% decline in eGFR from baseline over 2-3 years as surrogate outcome for kidney failure 1, 2, 3
• Perform routine urine sediment evaluation for red cell casts and acanthocytes 1
• Use 24-hour urine collection for total protein excretion in adults; first morning PCR in children 1

Kidney Biopsy Indications:

• Perform biopsy when diagnosis is uncertain, in atypical disease progression, or in RPGN 1, 2, 6
• Consider repeat biopsy only if it will alter diagnosis, therapeutic plan, or prognosis estimation 1, 2
• Biopsy is the gold standard but often not performed in critically ill patients due to clinical instability 8

Infection Prevention During Immunosuppression

When immunosuppression is required:

• Screen for latent tuberculosis, hepatitis B, hepatitis C, HIV, and syphilis prior to initiation 1, 3
• Administer pneumococcal vaccine, influenza vaccine, and herpes zoster vaccination (Shingrix) 1, 3
• Consider prophylactic trimethoprim-sulfamethoxazole for patients on high-dose prednisone or other immunosuppressants 1, 3
• Screen for Strongyloides in patients from endemic tropical environments with eosinophilia 1

Critical Complications Requiring Urgent Intervention

• Hypertensive encephalopathy: Use nifedipine for acute blood pressure control 4
• Congestive heart failure from profound volume expansion: Aggressive diuresis 5, 6
• Severe acute kidney injury: Consider renal replacement therapy (dialysis) 9, 6
• Adjust all medication doses according to GFR to prevent toxicity 1, 9

Common Pitfalls

• Do not delay antibiotic treatment in post-streptococcal GN waiting for culture confirmation 1, 5
• Avoid routine immunosuppression in classic post-infectious GN as it carries substantial risks without proven benefit 1, 4
• Do not use corticosteroids to prevent nephritis in isolated extrarenal IgA vasculitis 1
• The safety of protein restriction has not been established in children with GN 1, 2