Transplant rejection occurs when the recipient’s immune system attacks the transplanted organ. This can cause the transplanted organ to fail, undermining the purpose of the transplant and leading to a life threatening situation.
Transplant rejection can be an acute reaction occurring immediately after a transplant or a few days later. The outlook
Chronic organ rejection is a longer-term complication and is especially common in people who have kidney transplants. It can lead to the failure of the transplant and, eventually, of the organ. Without appropriate treatment and management, chronic organ rejection can be fatal.
Read on to learn more about transplant rejection.
Any transplanted tissue is a foreign object in the body. Although transplants can save lives, the immune system does not recognize them as part of the body. So, the immune system may attack the organ, attempting to get rid of it.
The reaction is often more intense when significant differences exist between the organ recipient and the organ donor. Therefore, doctors carefully select organ and tissue transplants, ensuring a good match of blood and tissue types and some antibodies. However, even with this match, the donor’s immune system may still attack the transplant.
Three types of rejection can occur:
This is an immediate rejection that occurs just a few hours or even minutes after surgery. It is more likely when the recipient’s antibodies counteract the donor’s antigens. Antigens are substances that the immune system reacts to.
Interacting with the donor’s antigens can cause blood clots to form, preventing a blood supply to the new tissue from developing and causing the transplant to fail.
All transplants have some degree of acute rejection, which is the initial failure of the immune system to recognize the new tissue as part of the body. Acute rejection usually occurs in the first 6 months.
The severity of the rejection reaction varies, but more extreme reactions can cause the organ to fail.
This refers to the ongoing rejection of the transplanted tissue or rejection that occurs months or years later. While it can occur with any organ, it is
Acute and hyperacute rejection
Chronic rejection causes signs of organ failure, which may trigger feelings of general unwellness, such as:
Some other tests a doctor might recommend include:
A group of drugs to weaken the immune system, called immunosuppressants, can help prevent rejection. They may also treat the early signs of rejection. People already taking immunosuppressants may need a higher dose or a different drug.
Ongoing clinical trials are identifying additional drugs that may improve the outlook for transplant rejection or treat it.
A person may also need treatment for complications. These interventions might include:
- whether there is organ damage and its extent
- a person’s overall health and what rejection complications they experience
- the availability of another organ and the ability to get on the transplant list if someone needs another transplant
Following a transplant, people with signs of organ rejection or infection should immediately contact their transplant team or surgeon. The surgeon in charge of a person’s care should give detailed instructions about who to contact and under what circumstances if the individual has any questions.
Before transplant, doctors attempt to reduce the risk of rejection by testing for the following:
- blood type
- histocompatibility, which is a matching process for antigens in the donor and recipient
- additional factors, such as antibodies a transplant recipient may have
After a transplant, a person must take immunosuppressive drugs to reduce the risk of an immune system reaction to the transplanted organ or tissue. This is usually a lifelong course of treatment.
Even with these measures, it is not always possible to prevent rejection. Seeking prompt medical care for early signs of rejection may help prevent organ failure.
Some degree of organ rejection is a typical part of transplants, as the immune system attacks foreign invaders. Even though a transplanted organ can be life-saving, it is an invader from the immune system’s perspective.
Working with a skilled transplant team, a person should discuss the risks and benefits of transplant, strategies for managing rejection, and what to do if they experience signs of rejection. With the right care, it is often possible to survive rejection and for the body to eventually accept the organ.