Renal biopsy

Definition – What is a kidney biopsy?

A kidney biopsy refers to a tissue sample from one or both kidneys. The word kidney puncture is used synonymously. By means of a kidney biopsy, the cause of impaired kidney function can be reliably identified. It is the gold standard, i.e. the diagnosis of choice, for unclear kidney function restrictions. This enables a suitable therapy plan to be drawn up for the disease in question.

Indication for kidney biopsy

In general, the indication for a kidney biopsy, as for any other diagnostic measure, can be given if the diagnostic benefit exceeds the potential risks. Indications for a kidney biopsy may be acute renal failure, chronic renal insufficiency, systemic lupus erythematosus, blood in the urine (haematuria) or protein in the urine (proteinuria) with suspected progressive kidney disease, changes in the kidney with suspected cancer, or problems following a kidney transplant.

Preparations before a kidney biopsy

The preparation prior to a kidney biopsy should always be done in consultation with the doctor in charge. In principle, care should be taken to ensure that anticoagulant medication is discontinued in good time. It is important to discuss with the doctor when to stop taking which medication and when to take it again after the operation.

In addition, a blood test is usually carried out before a kidney biopsy. Here it is important to determine the blood coagulation and inflammation values. A kidney biopsy is usually performed under local anaesthesia.

Nevertheless, it is recommended to fast during the procedure. This means that the last solid meal is usually eaten the evening before and only water or tea may be drunk up to about 4 hours before the procedure. Here too, it is recommended to consult the doctor who will be treating you.

Is a kidney biopsy painful?

A kidney biopsy is usually not painful as the skin is anaesthetised with a local anaesthetic. The biopsy of the kidney itself does not hurt. It is possible that a slightly unpleasant feeling of pressure may occur during the biopsy.

If pain develops at the biopsy site after the biopsy, painkillers such as paracetamol can be used. Strong pain should not be felt after a kidney biopsy. Aspirin should not be taken for three days after the biopsy, as this can lead to increased bleeding.

Is a kidney biopsy performed under anesthesia?

Anesthesia is usually not necessary for a kidney biopsy. The skin, the tissue under the skin and the muscles are anaesthetised with a local anaesthetic. The kidney itself is not painful.

Therefore the procedure is not painful. If necessary, something can be given additionally to calm the patient down. A kidney biopsy under anaesthesia is therefore only performed in exceptional cases.