Membranous glomerulonephritis



Introduction
Epidemiology
Aetiology
Clinical features
Investigations
Management
Prognosis


Introduction

Membranous glomerulonephritis is the commonest type of glomerulonephritis in adults and is the third most common cause of end-stage renal failure (ESRF). It usually presents with nephrotic syndrome or proteinuria.

Epidemiology

  • Incidence: 2.00 cases per 100,000 person-years
  • Peak incidence: 50-60 years
  • Sex ratio: 1:1
<1 1-5 6+ 16+ 30+ 40+ 50+ 60+ 70+ 80+

Aetiology

Causes
  • idiopathic: due to anti-phospholipase A2 antibodies
  • infections: hepatitis B, malaria, syphilis
  • malignancy: lung cancer, lymphoma, leukaemia
  • drugs: gold, penicillamine, NSAIDs
  • autoimmune diseases: systemic lupus erythematosus (class V disease), thyroiditis, rheumatoid

Clinical features

Investigations

Renal biopsy demonstrates:
  • electron microscopy: the basement membrane is thickened with subepithelial electron dense deposits. This creates a 'spike and dome' appearance

Management

Management
  • all patients should receive an ACE inhibitor or an angiotensin II receptor blocker (ARB):
    • these have been shown to reduce proteinuria and improve prognosis
  • immunosuppression
    • as many patients spontaneously improve only patient with severe or progressive disease require immunosuppression
    • corticosteroids alone have not been shown to be effective. A combination of corticosteroid + another agent such as cyclophosphamide is often used
  • consider anticoagulation for high-risk patients

Prognosis

Prognosis - rule of thirds
  • one-third: spontaneous remission
  • one-third: remain proteinuric
  • one-third: develop ESRF

Good prognostic features include female sex, young age at presentation and asymptomatic proteinuria of a modest degree at the time of presentation.