The patient's immune system and white blood cells recognize the transplanted organ as being foreign and mount a defense against the organ. The new organ is then incapable of working at full efficiency, and symptoms of rejection become apparent to the transplant recipient. These symptoms of rejection are very similar to the symptoms of organ failure. Early detection is essential to successful reversal of acute rejection. For this reason, the transplant recipient carries a large responsibility for maintaining his or her health.
Acute rejection is almost always reversible with special medication.
Once successfully reversed, some patients never have trouble with acute rejection again, although some patient do have subsequent episodes. Most rejection episodes require admission to the hospital. Acute rejection is rare beyond the first year of transplant. In addition to the subjective symptoms of worsening organ function that the transplant recipient feels, there are indicators of organ rejection which the health care team can identify. Chronic rejection is different from acute rejection in that it is usually not reversible, but it is also a response of the patient's immune system.