Kidney biopsy is a diagnostic method that is performed mainly in nephrology departments. Its main goal is to obtain a small sample of kidney tissue for histological examination.
The intervention is usually done in horizontal prone position under ultrasound or CT control. After the local anatomy is evaluated, the skin is disinfected, local anesthetic is applied and the physician performs the puncture. The syringe is constructed to hold a small sample of the tissue. If necessary, the puncture may be repeated.
After the procedure, bed rest is usually ordered and the patient is administered painkillers, if needed. Blood pressure and heart rate are regularly measured and at least basic urinalysis is performed.
The actual examination is performed under local anesthesia, the patient is conscious. Special preparation before the procedure is not necessary, but the patient should discontinue any stronger anticoagulants few days before the biopsy (of course, only after consulting a doctor). Actual blood pressure and blood clotting parameters are usually checked before the intervention.
Kidney biopsy is a relatively invasive examination, it has its risks and therefore, it should not be performed routinely. However, it is the only solution when we need a sample of kidney tissue. The most common indications are acute or chronic renal failure of unknown origin, especially when we have a suspicion of a glomerulonephritis. Using special immunohistochemical methods, the histology can confirm presence of glomerulonephritis and determine its type.
The procedure can be sometimes painful and the puncture may cause local bleeding with kidney hematoma or with presence of blood in urine. However, the bleeding is usually not massive and subsides spontaneously. Although the procedure is carried out strictly aseptically, there is a small risk of bacterial infection of the subcutaneous tissue or even bacterial pyelonephritis.
The kidney biopsy is a relatively quick method, which gives us the possibility to directly examine the kidney tissue. It is a very important diagnostic method for patients with deterioration of renal functions from an unknown cause.