From the Guidelines
A comprehensive glomerulonephritis screen should include urinalysis with microscopy, blood tests, immunologic studies, and consideration of a kidney biopsy, as recommended by the most recent guidelines 1. When evaluating a patient for glomerulonephritis, it is essential to start with a thorough urinalysis to assess for proteinuria, hematuria, and cellular casts, along with a 24-hour urine collection to quantify protein excretion.
- Blood tests should include:
- Complete blood count
- Comprehensive metabolic panel (focusing on BUN, creatinine, electrolytes)
- Estimated glomerular filtration rate (eGFR)
- Immunologic testing should include:
- Complement levels (C3, C4)
- Antinuclear antibody (ANA)
- Anti-neutrophil cytoplasmic antibodies (ANCA)
- Anti-glomerular basement membrane antibodies (anti-GBM)
- Anti-streptolysin O titers (ASO)
- Serum protein electrophoresis Additional tests may include hepatitis B and C serologies, HIV testing, and cryoglobulins. Consider ordering anti-phospholipase A2 receptor antibodies for suspected membranous nephropathy, as suggested by the KDIGO 2021 guideline for the management of glomerular diseases 1. A renal biopsy may ultimately be necessary for definitive diagnosis and treatment planning, especially in cases with significant proteinuria, hematuria, or declining renal function, as emphasized in the KDOQI US commentary on the 2021 KDIGO clinical practice guideline for the management of glomerular diseases 1. The diagnostic strategy in rapidly progressive glomerulonephritis should involve evaluating for non-glomerular etiology of acute kidney injury, obtaining autoimmune serologies, and considering a kidney biopsy if feasible, as outlined in the executive summary of the KDIGO 2021 guideline for the management of glomerular diseases 1.
From the Research
Glomerulonephritis Screen Tests
To diagnose glomerulonephritis, several tests can be ordered, including:
- Urinalysis to check for proteinuria and hematuria 2
- Blood tests to measure renal function, such as eGFR, and to check for low serum albumin levels 2
- Blood pressure measurement, as patients with nephritic syndrome often present with hypertension 2
- Complement levels, such as C3, to help diagnose specific types of glomerulonephritis, like C3 glomerulonephritis 3, 4, 5
- Renal biopsy, which is considered the gold standard for diagnosing glomerulonephritis, to examine kidney tissue and identify specific patterns of injury 3, 6
Additional Tests
Depending on the clinical presentation and suspected underlying cause, additional tests may be ordered, including:
- Autoantibody tests, such as anti-neutrophil cytoplasmic antibody (ANCA) or anti-glomerular basement membrane (anti-GBM) antibody, to diagnose specific types of glomerulonephritis 4, 5
- Genetic testing, to identify genetic mutations associated with glomerulonephritis, such as mutations in the CFH, CFI, or CFHR genes 3, 5
- Proteomic analysis, to identify biomarkers for chronic kidney disease and glomerulonephritis 6