What is the management of acute glomerulonephritis in children?

Management of Acute Glomerulonephritis in Children

Management of acute glomerulonephritis in children is primarily supportive, focusing on controlling hypertension, managing fluid overload with diuretics and sodium restriction, and monitoring for complications, with immunosuppression reserved only for severe crescentic disease or rapidly progressive glomerulonephritis. 1, 2

Initial Assessment and Diagnosis

Kidney biopsy is the gold standard for diagnosis but is not routinely required for typical acute post-streptococcal glomerulonephritis (APSGN), which is the most common form in children. 1, 3 Reserve biopsy for:

• Diagnostic uncertainty 2
• Rapidly progressive glomerulonephritis 2, 4
• Atypical disease progression 2
• Extensive glomerular crescents on presentation 4

For proteinuria assessment, obtain a first morning protein-creatinine ratio (PCR) rather than 24-hour urine collection in children. 1, 3 Use the modified Schwartz equation to calculate eGFR in pediatric patients. 1, 3

Perform routine urine sediment examination for red cell casts and acanthocytes, which are characteristic findings. 1, 3

Supportive Care Management

Fluid and Sodium Management

Restrict dietary sodium to <2.0 g/day as the cornerstone of managing fluid overload, edema, and hypertension. 5, 3 This is critical because hypervolemia is the primary driver of complications in acute glomerulonephritis. 2, 6

Use diuretics as first-line agents for edema management. 1, 5 If response is insufficient, add mechanistically different diuretics (e.g., combine loop diuretic with thiazide). 1, 5 Monitor closely for:

• Hyponatremia 5
• Hypokalemia 5
• GFR reduction 5
• Volume depletion 5

Blood Pressure Control

Target 24-hour mean arterial pressure at ≤50th percentile for age, sex, and height using ambulatory blood pressure monitoring. 5, 3

Use ACE inhibitors or ARBs at maximally tolerated doses as first-line antihypertensive therapy when proteinuria is present. 5, 3 However, hold RAS inhibitors during intercurrent illnesses with risk of volume depletion to prevent acute kidney injury. 3

For acute hypertensive emergencies, nifedipine has demonstrated advantages in controlled trials for acute blood pressure control. 7 ACE inhibitors (captopril and enalapril) provide better control of blood pressure and echocardiographic changes compared to other antihypertensive drugs. 7

Monitoring for Life-Threatening Complications

Watch for and aggressively treat:

• Hypertensive encephalopathy 2, 6
• Congestive heart failure 2, 6
• Pulmonary edema 2, 6

These complications occur during the acute phase due to hypervolemia and require immediate intervention. 2, 6

Antimicrobial Therapy

Antimicrobial therapy does not prevent APSGN or alter its course once glomerulonephritis has developed. 7 No advantages were found for cefuroxime, ceftibuten, or other antimicrobials given for 5 days compared to penicillin V for 10 days. 7

However, treat any active streptococcal infection to prevent transmission and eliminate the source. 2

Immunosuppressive Therapy

Standard APSGN (Non-Crescentic)

Do not use immunosuppression for typical acute post-streptococcal glomerulonephritis. 7, 4 The disease is self-limiting with excellent prognosis, and treatment is supportive only. 7, 2, 6

Crescentic or Rapidly Progressive Glomerulonephritis

For rapidly progressive glomerulonephritis with extensive crescents and deteriorating renal function, initiate pulsed intravenous methylprednisolone immediately. 4 This approach reduces renal mortality from 85%-90% to approximately 25% when combined with plasma exchange. 4

Treatment algorithm for crescentic disease:

1. Start with pulsed methylprednisolone 4
2. Add plasma exchange for patients who fail to respond or deteriorate after temporary response 4
3. Treatment must be given early in the disease course to achieve good outcomes 4

The combination of immunosuppressants for crescentic post-streptococcal glomerulonephritis showed no advantages over supportive therapy alone in one study, highlighting the importance of using the pulsed methylprednisolone and plasma exchange approach instead. 7

Renal Replacement Therapy

Consider dialysis for:

• Severe acute kidney injury 8
• Refractory fluid overload 8, 2
• Life-threatening hyperkalemia
• Severe uremia

Only a small number of patients require kidney replacement therapy. 2

Dietary Management

Adjust protein intake based on degree of proteinuria and kidney function. 3 Target caloric intake of 35 kcal/kg/day, and for eGFR <60 ml/min/1.73 m², limit to 30-35 kcal/kg/day. 3 Avoid protein restriction <0.6 g/kg/day due to safety concerns and risk of malnutrition, particularly in children. 3

Monitoring and Follow-Up

Assess proteinuria regularly as reduction indicates treatment response. 5, 3 Monitor for a ≥40% decline in eGFR from baseline over 2-3 years as a surrogate outcome for kidney failure. 5, 3

Long-term monitoring is essential because persistent proteinuria, hypertension, and progression to chronic kidney disease may occur despite initial recovery. 2, 9 Decreased complement levels, increased C-reactive protein, hypoalbuminemia, crescent formations on biopsy, and renal insufficiency at presentation predict disease severity and poor outcomes. 6

Common Pitfalls

• Do not delay treatment in crescentic disease - early intervention is critical for preserving renal function 4
• Do not use traditional oral steroids and immunosuppressants alone for crescentic disease - pulsed methylprednisolone with plasma exchange is superior 4
• Do not assume all cases have excellent prognosis - sporadic cases have poorer long-term outcomes than epidemic forms 7
• Do not overlook the need for long-term follow-up even in patients who appear to recover completely 2, 6