What are the KDIGO guidelines and recommended management for pediatric post‑streptococcal glomerulonephritis?

Management of Pediatric Post-Streptococcal Glomerulonephritis

Post-streptococcal glomerulonephritis (PSGN) in children is managed primarily with supportive care—no immunosuppression is needed in typical cases—focusing on controlling hypertension, edema, and hypervolemia, as the disease is self-limiting with excellent prognosis in most patients 1, 2.

Core Management Principles

Supportive Care is the Foundation

PSGN management centers on treating complications rather than the underlying immune process, since spontaneous recovery occurs in the vast majority of cases 1, 2, 3. The disease resolves without specific therapy targeting the immune complex deposition.

Fluid and Sodium Management

• Restrict dietary sodium to <2.0 g/day (<90 mmol/day) 4
• Implement fluid restriction in patients with volume overload
• This addresses the hypervolemia that drives most acute complications

Edema Management

Use loop diuretics as first-line therapy 4:

• Twice-daily dosing is preferred over once-daily dosing
• Increase the dose until clinically significant diuresis occurs or maximum effective dose is reached
• If furosemide fails, switch to longer-acting loop diuretics (bumetanide or torsemide)

For resistant edema, add mechanistically different diuretics 4:

• Thiazide diuretics combined with loop diuretics impair distal sodium reabsorption
• Amiloride counters hypokalemia and helps with metabolic alkalosis
• Spironolactone provides additional benefit but monitor for hyperkalemia

Monitor closely for diuretic adverse effects 4:

• Hypokalemia (thiazides and loop diuretics)
• Hyponatremia (thiazides)
• Volume depletion—particularly critical in pediatric patients
• Impaired GFR

Hypertension Management

Target 24-hour mean arterial pressure at the 50th percentile for age, sex, and height by ambulatory blood pressure monitoring 4.

Use ACE inhibitors or ARBs as first-line for hypertension with proteinuria 4:

• Uptitrate to maximally tolerated dose
• Critical caveat: Do NOT start ACEi/ARB in patients with abrupt onset nephrotic syndrome, as these can cause AKI 4
• Tolerate modest, stable creatinine increases up to 30%
• Stop if kidney function continues worsening or refractory hyperkalemia develops

For acute hypertensive emergencies (encephalopathy, pulmonary edema), use immediate-acting antihypertensives with close monitoring 1, 2.

Monitoring and Assessment

Initial Evaluation

Quantify proteinuria using first morning protein-creatinine ratio (PCR) in children 4:

• Goal PCR <200 mg/g (<20 mg/mmol) or <8 mg/m²/hour in 24-hour urine
• Accept higher baseline only with kidney biopsy evidence of scarring

Assess kidney function using the modified Schwartz equation 4, 5:

• The Full Age Spectrum (FAS) equation is also valid

Evaluate urine sediment for 4:

• Erythrocyte morphology
• Red cell casts
• Acanthocytes

Follow-up Timeline

Monitor at 4 weeks and 12 weeks after presentation 6:

• Most clinical features resolve within 3 months
• At 3 months, approximately 6.5% may have persistent hypertension, impaired kidney function, or proteinuria 6
• Continue long-term monitoring for those with persistent abnormalities

When to Escalate Care

Indications for Kidney Biopsy

Kidney biopsy is rarely required but consider when 1, 2:

• Diagnostic uncertainty exists
• Rapidly progressive glomerulonephritis develops
• Atypical disease progression occurs
• Persistent proteinuria, hypertension, or declining kidney function at 3 months

Indications for Immunosuppression

Immunosuppression (corticosteroids) is needed only in a small minority 1, 2:

• Rapidly progressive glomerulonephritis with crescents on biopsy
• Severe, persistent disease not responding to supportive care
• Approximately 12% of hospitalized patients may require this escalation 6

Indications for Renal Replacement Therapy

Dialysis may be necessary for 1, 2:

• Severe acute kidney injury unresponsive to medical management
• Life-threatening hyperkalemia
• Severe volume overload with pulmonary edema refractory to diuretics
• Uremic complications

Antibiotic Considerations

While not explicitly detailed in KDIGO guidelines, treat any active streptococcal infection with appropriate antibiotics (typically penicillin) to eradicate the organism, though this does not alter the course of established PSGN 1, 3.

Prognosis and Long-term Outcomes

The prognosis is generally excellent 1, 2, 3:

• Most patients (84.4%) have an uncomplicated course 6
• Complete recovery is the norm
• Mortality is rare in developed healthcare settings
• A small percentage may develop chronic kidney disease, requiring long-term monitoring

Predictors of worse outcomes 2:

• Decreased complement levels
• Increased C-reactive protein
• Hypoalbuminemia
• Crescent formation on biopsy
• Renal insufficiency at presentation

Common Pitfalls to Avoid

1. Do not start ACEi/ARB in acute nephrotic presentations—risk of AKI is significant 4
2. Do not over-diurese—volume depletion is particularly dangerous in children 4
3. Do not routinely use immunosuppression—PSGN is self-limiting and does not require it in typical cases 1, 2
4. Do not discharge without follow-up plan—persistent abnormalities at 3 months require ongoing monitoring 6