From the Guidelines
Diagnosing and treating glomerulonephritis requires a systematic approach based on the specific type of glomerular inflammation present, with treatment varying by type and prioritizing morbidity, mortality, and quality of life as the primary outcome. Diagnosis typically begins with urinalysis to detect proteinuria, hematuria, and cellular casts, followed by blood tests to assess kidney function (creatinine, BUN), complement levels, and autoimmune markers 1. A kidney biopsy is often necessary for definitive diagnosis, allowing pathologists to examine glomerular tissue under light, immunofluorescence, and electron microscopy.
Key Considerations in Diagnosis and Treatment
- The intensity of induction therapy is predicated on the severity of presenting symptoms and type of glomerulonephritis, with the level of GFR needing to be taken into account for determining safe dosage 1.
- Treatment varies by type:
- Minimal change disease typically responds to prednisone (1 mg/kg/day for 4-16 weeks)
- Focal segmental glomerulosclerosis may require calcineurin inhibitors like tacrolimus or cyclosporine
- Membranous nephropathy often responds to rituximab (1 g IV on days 1 and 15)
- IgA nephropathy may benefit from ACE inhibitors/ARBs and sometimes corticosteroids
- Lupus nephritis requires immunosuppression with mycophenolate mofetil (2-3 g/day) or cyclophosphamide plus steroids
- ANCA-associated vasculitis needs aggressive immunosuppression with cyclophosphamide or rituximab plus high-dose steroids
- Supportive care is essential for all types, including blood pressure control (target <130/80 mmHg), proteinuria reduction with ACE inhibitors/ARBs, dietary sodium restriction (<2 g/day), and careful monitoring of kidney function 1.
Importance of Early Nephrology Referral
Early nephrology referral is crucial, as delayed treatment can lead to irreversible kidney damage and progression to end-stage renal disease requiring dialysis or transplantation. The classification of glomerulonephritis into different types, such as those outlined by the International Society of Nephrology/Renal Pathology Society (ISN/RPS), is vital for guiding treatment decisions and predicting outcomes 1.
Recent Guidelines and Recommendations
Recent guidelines, including the KDIGO 2021 guideline for the management of glomerular diseases, emphasize the importance of choosing a treatment regimen that prevents disease progression and averts immediate morbidity, with proteinuria reduction being a key surrogate endpoint in the treatment of glomerulonephritis 1.
From the Research
Diagnosis of Glomerulonephritis
To diagnose and treat different types of glomerulonephritis, the following steps can be taken:
- Identify the clinical presentation, which can range from asymptomatic hematuria and proteinuria to fulminant renal failure 2
- Use serologic and urinary testing to refine the differential diagnosis 2
- Perform a renal biopsy for definitive diagnosis, which is the gold standard for diagnosing glomerulonephritis 3
- Classify glomerulonephritis based on the underlying cause and pathogenetic mechanisms, rather than just histopathological patterns 3
Classification of Glomerulonephritis
Glomerulonephritis can be broadly classified into several categories, including:
- Immune-complex glomerulonephritis (including infection-related glomerulonephritis, IgA nephropathy, lupus nephritis, and cryoglobulinaemic glomerulonephritis) 3
- Anti-neutrophil cytoplasmic antibodies-associated (pauci-immune) glomerulonephritis 3
- Anti-glomerular basement membrane glomerulonephritis 3
- C3 glomerulopathy 3
- Monoclonal immunoglobulin-associated glomerulonephritis 3
Treatment of Glomerulonephritis
Treatment of glomerulonephritis can include:
- Supportive care 2
- Renin-angiotensin-aldosterone system blockade 2
- Immunomodulatory therapy 2
- Renal transplant 2
- The prognosis is largely dependent on the underlying cause of glomerulonephritis and can vary from a self-limited course to chronic kidney disease 2
Diagnostic Approach
A systematic and inclusive approach to the differential diagnosis of glomerular disease can be used, which includes: