A biopsy is the removal of a small piece of tissue from an organ of the body. It allows the tissue removed to be examined under a microscope in a laboratory in order to see if there are any changes to the blood vessels and cells of the kidney.
After a transplant, it is necessary to monitor changes in the kidney closely. There are two main indications for biopsy: firstly, an increase in creatinine in the first few days after transplantation when it is possible the kidney is "sleeping". This needs to be monitored closely to ensure that there is no damage to the kidney, and a biopsy is required for this; secondly, at later stages, it is necessary to confirm the diagnosis of rejection in order for treatment to commence promptly.
You will be asked for your consent to the biopsy and the risks explained to you before you give that consent.
You blood will be sampled in order to check that it is clotting normally.
The procedure for transplant biopsy is the same as that for non-transplant kidney biopsy, except that you will be asked to lie on your back.
The position of the graft kidney is then checked using an ultrasound scan. When the doctor is ready to proceed, the skin of the back will be cleaned with an antiseptic solution and green towels placed over the area and a painkilling injection will be given to numb the area. It takes a little while for this to work. When it is working, you will be asked to hold your breath and keep still. At this moment a special biopsy needle is introduced through the skin into the kidney to take the small sample. This will make a short sharp sound. This part of the procedure is very quick but may be repeated more than once to get sufficient tissue for analysis.
Once the sample has been taken and a small dressing applied to the biopsy site you will be asked to stay lying on a bed for a period of time, usually about six hours. Your blood pressure and pulse will be monitored frequently and the wound site dressing checked to make sure that everything is well after the biopsy. Some people see some blood in their urine after a biopsy, this is not unusual and is not a cause for concern. Painkillers will be prescribed for you if you need them. If you are having a biopsy as a day patient, you should be ready to go home after about six hours.
Any medical or surgical procedure carries risks. Patients are only asked to undergo procedures because it is felt that the risks are outweighed by the benefits of diagnosis and treatment. For example, rarely, a patient might have a small bleed in the kidney after a biopsy which may cause blood in the urine. All possible precautions are taken to prevent bleeding. When it does occur, patients are observed closely and treated according to their needs.
After the initial bed rest you will be allowed to get up and walk about slowly. It is important that you drink plenty of fluids to increase your urine output. No lifting heavy objects or strenuous exercise is advised for the first few days, but after that there should be no reason why normal activities could not be restarted. The dressing over the wound site should be kept dry and intact for 24 to 48 hours. After this you may remove it and shower or bath providing that the wound is dry.
If you experience dizziness, blood in your urine or any signs of infection such as a raised temperature, bleeding, swelling, redness or increased pain from the wound site, please contact the Renal Unit.
The results of a transplant biopsy are available in a few hours so that appropriate treatment can be started as soon as possible