Transplant Rejection

Key facts

• After a transplant, the immune system can identify the new organ as foreign and attack it; rejection can occur days after surgery or years later and needs lifelong management.
• Rejection often causes no obvious symptoms, which is why transplant teams schedule regular biopsies and blood tests; sudden changes in how you feel need prompt contact with the team.
• Prevention combines autoimmune support medicines: calcineurin inhibitors tacrolimus and ciclosporin, cell-suppressing mycophenolate mofetil and azathioprine, and sirolimus through a different pathway.
• Doses balance rejection risk against infection risk and are reviewed frequently.

Recognising rejection

Rejection does not always cause obvious symptoms, hence the routine monitoring. When symptoms appear they vary by organ: a kidney rejection may cause reduced urine output, swelling and tenderness over the graft; a liver rejection can present as jaundice and raised liver enzymes; a heart recipient may notice breathlessness or fatigue. Fever and a general feeling of illness are common across organ types.

Keeping the immune system in check

Prevention is the foundation of transplant care. Medicines from the autoimmune support class are combined to suppress the immune response without disabling it. Tacrolimus and ciclosporin target calcineurin, a protein central to the immune cascade. Mycophenolate mofetil and azathioprine reduce the production of immune cells that attack the graft. Sirolimus works through a different pathway and is often used when calcineurin inhibitors are not well tolerated. Most recipients take two or three agents together at the lowest dose that keeps the organ stable.

When to seek help

Contact your transplant team promptly for any sudden change after a transplant, fever, or a fall in organ function; lifelong immunosuppression and specialist follow-up are essential.

This page is educational and does not replace advice from a doctor or pharmacist who knows your health history.