How and why does the body reject a transplanted kidney? What happens then?


Organ transplants are increasingly successful, and many kidney transplant recipients continue to lead long, fulfilling lives following surgery. Occasionally, a transplant recipient’s immune system may detect something in the system, due in large part to cytotoxic antibodies, a substance in the blood, which can cause the recipient’s body to reject the donated kidney. Specialists will conduct extensive tests to minimize the risk of organ rejection in advance of the transplant surgery, and will often administer medication following the surgery to reduce this risk further (you can find more information about immunosuppressants further in this section). Patients may also experience acute rejection, an episode where the body detects the foreign object only temporarily. This is common in the first year following transplant, however it can also lead to chronic rejection. 

Chronic rejection, which is characterized by gradual loss of organ function, is an ongoing concern for transplant recipients because it can occur weeks, months or years after transplantation. Organ recipients should be aware of the signs of both acute and chronic rejection. Symptoms include:

  • Pain or tenderness over the transplant site
  • Fever
  • Flu-like symptoms such as chills, nausea, vomiting, diarrhea, tiredness, headache, dizziness and body aches and pains
  • Change in pulse rate
  • Weight gain
  • Swelling
  • Less urine