What is the treatment for nephritic syndrome?

Treatment for Nephritic Syndrome

The treatment of nephritic syndrome requires rapid referral to a specialized nephrology unit and includes disease-specific therapy targeting the underlying cause, along with supportive measures to manage symptoms and prevent complications. 1

Diagnosis and Classification

Before initiating treatment, proper diagnosis is essential:

• Clinical presentation: Hematuria, hypertension, variable proteinuria (typically non-nephrotic range), fluid retention, and edema 1
• Laboratory findings: Elevated serum creatinine, urinalysis showing RBCs and RBC casts, possible low complement levels (C3, C4) in certain causes 1
• Classification: Determine if the nephritic syndrome is:
  • Post-infectious (most commonly post-streptococcal)
  • IgA nephropathy
  • ANCA-associated vasculitis
  • Lupus nephritis
  • Other causes

Disease-Specific Treatment

Treatment varies based on the underlying cause:

1. Post-infectious glomerulonephritis:

   • Antimicrobial therapy for the underlying infection 1
   • Supportive care for symptoms

2. IgA nephropathy:

   • ACE inhibitors or ARBs for proteinuria control
   • Consider corticosteroids for persistent proteinuria 1

3. ANCA-associated vasculitis:

   • Cyclophosphamide or rituximab plus corticosteroids 1

4. Lupus nephritis (Class III/IV):

   • Initial treatment with mycophenolate mofetil or cyclophosphamide, plus glucocorticoids
   • Maintenance therapy with MMF or azathioprine and low-dose prednisone for at least 3 years 1

5. Non-genetic, non-infectious causes:

   • Consider kidney biopsy if screening is negative
   • Trial of immunosuppressant therapy based on biopsy findings 2

Supportive Treatment

1. Fluid management:

   • Restrict sodium and fluid intake based on volume status assessment 2
   • Avoid intravenous fluids and saline when possible 2

2. Blood pressure control:

   • ACE inhibitors or ARBs are preferred agents 1
   • Target blood pressure to age-appropriate goals

3. Edema management:

   • Diuretics: Furosemide 0.5-2 mg/kg per dose intravenously or orally up to six times daily (maximum 10 mg/kg per day) 2, 1
   • For severe cases, consider combination therapy with thiazide or potassium-sparing diuretics 2
   • Monitor electrolytes, blood pressure, and kidney function during diuretic therapy

4. Antiproteinuric therapy:

   • ACE inhibitors or ARBs to reduce proteinuria 2, 1
   • Dose-dependent mechanism to reduce glomerular protein loss

5. Thromboprophylaxis:

   • Consider prophylactic anticoagulation in high-risk patients 1
   • Especially important if central venous access is required 2

Monitoring and Follow-up

Regular monitoring is essential:

• Body weight and blood pressure
• Renal function (serum creatinine, GFR)
• Proteinuria and urinary sediment
• Serum albumin and electrolytes
• Visits every 2-4 weeks during the first 2-4 months after diagnosis or flare 1

Response Assessment

• Complete response: Return of serum creatinine to baseline and decline in urine protein:creatinine ratio to <500-700 mg/g 1
• Partial response: Stabilization or improvement of serum creatinine but urine protein:creatinine ratio still >500-700 mg/g 1
• Consider repeat kidney biopsy in cases of worsening kidney function, non-responsiveness to treatment, or relapse 1

Special Considerations

1. Pediatric patients:

   • Monitor growth velocity, especially with prolonged corticosteroid treatment 1
   • Consider growth hormone substitution in children with growth issues 1

2. Ambulatory management:

   • Preferred when possible to improve quality of life and reduce infection risk 1

3. Severe cases:

   • Consider nephrectomy in patients with persistent severe symptoms despite optimal conservative treatment 1
   • Early referral to transplant unit when appropriate 2

Common Pitfalls to Avoid

• Delaying specialist referral for complex cases
• Inadequate thromboprophylaxis in high-risk patients
• Failure to monitor for and prevent infections in immunosuppressed patients
• Overreliance on immunosuppression for genetic forms of nephrotic syndrome 1
• Inadequate monitoring of electrolytes during diuretic therapy

By following this structured approach to the treatment of nephritic syndrome, focusing on both disease-specific therapy and supportive care, outcomes related to morbidity, mortality, and quality of life can be optimized.