One issue that occurs with transplantation is rejection. Rejection ours when your body recognizes the transplanted kidney as a foreign object. As a result, the body initiates the immune system to fight against it. This usually happens in the earlier months following the kidney transplant. Rejection can be analyzed through routine blood tests, renal scans, biopsy, ultrasound, and fine needle aspirations. These tests determine how well the new kidney is doing in your body. To prevent rejection, medications such as immunosuppressant are used. Although this can help, sometimes rejection may still occur and patients may need to be on dialysis.