A biopsy of the kidney may be necessary in the setting of decreased urine output, increased serum creatinine level, unexplained persistent fever of worrisome blood or protein in the urine. The biopsy can be done for many reasons including to evaluate for the possibility of rejection, recurrent kidney disease, drug toxicity or certain type of infections. Some children may have had kidney biopsies of their own kidneys before having a transplant. Those biopsies are done with the child lying face down on their abdomen. Because a transplant kidney is in a different place than the native kidney, a transplant kidney biopsy is done by a child lying on their back. The biopsy is done after consent is signed where the risks of biopsy will be explained and after it has been decided how the patient will be kept comfortable during biopsy. Each transplant center has different procedures with regard to sedation medications or anesthesia for the child and where in the facility biopsy will be done but all centers will have protocols for how the child is kept comfortable and safe during and after biopsy. The biopsy is commonly done with the assistance of the radiologists and most frequently ultrasound is used to guide the biopsy and increased safety. The biopsy typically will be done using a biopsy needle going through a very small incision made in a numbed area of overlying skin. Usually 2 to 3 pieces of kidney tissue are obtained and sent to the pathology lab for staining and processing, a procedure that can take anywhere from one to three days to complete. The primary risk of a kidney biopsy is bleeding so certain medications that may increase the risk of bleeding may need to be stopped or held before and after the biopsy. Your transplant center will tell you if any medication changes need to be made. Following the biopsy some children are kept in the hospital overnight while others might be able to go home after a periode of observations for complications. Each transplant center will have their own protocol for how this occurs. Your child will have some activity restrictions after the biopsy which your transplant center will review with you.