From the Guidelines
A renal biopsy is indicated when a patient has unexplained kidney dysfunction, persistent proteinuria, hematuria of glomerular origin, or suspected kidney disease that requires specific diagnosis for appropriate treatment, as supported by the most recent guideline from 2024 1. The decision to perform a renal biopsy should be based on a thorough evaluation of the patient's clinical presentation, laboratory results, and imaging studies.
- Specific indications for renal biopsy include:
- Nephrotic syndrome (protein excretion >3.5g/day)
- Acute kidney injury without clear cause
- Persistent proteinuria (>1g/day)
- Systemic diseases with kidney involvement like lupus or vasculitis
- Unexplained chronic kidney disease
- The procedure involves removing a small tissue sample from the kidney using a needle, usually guided by ultrasound or CT imaging, and is generally safe, but contraindications include bleeding disorders, uncontrolled hypertension, solitary kidney (relative contraindication), and active kidney infection, as noted in a study from 2019 1.
- The biopsy provides valuable information about the underlying pathology, disease severity, and prognosis, allowing physicians to develop targeted treatment plans rather than empiric therapy, as highlighted in a study from 2023 1.
- In patients with suspected kidney disease, a renal biopsy can be useful in determining the underlying cause of the disease and guiding treatment, as recommended by the joint European League Against Rheumatism and European Renal Association-European Dialysis and Transplant Association (EULAR/ERA-EDTA) in 2012 1.
- The risks associated with underdiagnosis of potentially treatable conditions should be balanced against those of complications from the biopsy procedure, and patients with suspected kidney disease should be thoroughly evaluated to determine the need for a renal biopsy, as discussed in a study from 2019 1.
From the Research
Indications for Renal Biopsy
A renal biopsy is indicated in various clinical scenarios, including:
- Suspected intrinsic kidney disease, such as glomerulonephritis, lupus nephritis, or membranous nephropathy 2, 3, 4
- Acute kidney injury (AKI) with unknown cause or suspected glomerular disease 4, 5
- Nephrotic syndrome or nephritic syndrome with unknown cause 3, 6
- Chronic kidney disease with unknown cause or suspected underlying glomerular disease 2, 3
- Monitoring of kidney disease progression or response to treatment 3
Specific Clinical Scenarios
Renal biopsy may be indicated in specific clinical scenarios, such as:
- Patients with diabetes, lupus, or myeloma with suspected kidney involvement 2
- Older patients with suspected kidney disease or AKI 2
- Patients with AKI and coexisting glomerulopathy, such as IgA nephropathy or lupus nephritis 5
- Patients with nephritic syndrome or rapidly progressive glomerulonephritis (RPGN) 4, 6
Diagnostic Yield and Safety
Renal biopsy can provide significant diagnostic information and guide prognosis and management, but it is an invasive procedure with potential risks, including bleeding complications 3. The use of semi-automatic spring-loaded biopsy devices and real-time ultrasound can reduce the complication rate 3. A coagulation disorder should be excluded beforehand, and an elevated blood pressure should be reduced to the normotensive range with medications 3.