A medical graft involves transplanting tissue or an organ to a patient. This can come from a donor or another part of the patient’s own body. Graft failure is a broad term for when this transplanted material does not work as it should. It may fail to function from the start, lose its function over time, or be attacked by the recipient’s body.
Why Grafts Can Fail
The body’s immune system is a primary reason for graft failure. It is designed to attack foreign invaders and can see a new organ or tissue as a threat, a response called rejection. Rejection can happen very quickly (hyperacute), occur over days to weeks (acute), or develop slowly over months or years (chronic).
Grafts can also fail for reasons not directly related to the immune system. Technical problems during the transplant surgery, such as issues with connecting blood vessels, can prevent the graft from receiving the blood it needs to survive. Infections, either within the graft itself or throughout the patient’s body, can also compromise its function. The original disease that made the transplant necessary can return and damage the new graft.
The type of graft influences the potential causes of failure. For instance, in bone marrow transplants, low numbers of transplanted stem cells can lead to failure. With skin grafts, poor blood supply to the wound bed can prevent the graft from taking hold. The medications used to prevent rejection can also have toxic effects that contribute to graft failure.
Identifying Signs of Graft Failure
The signs that a graft may be failing can be general or specific to the transplanted tissue. General symptoms include fever, pain, swelling, and redness at the location of the graft. A patient might also experience a general feeling of being unwell. These symptoms can sometimes be subtle or develop slowly over time.
Symptoms can also be specific to the type of graft. With a kidney transplant, signs of failure might include producing less urine, retaining fluid, or developing high blood pressure. For a liver graft, signs include yellowing of the skin and eyes (jaundice) or swelling in the abdomen. A failing heart graft can lead to shortness of breath, fatigue, or an irregular heartbeat.
In the case of skin grafts, changes in the appearance of the graft are a key indicator. The skin might turn dark or pale, or it could begin to separate from the wound. For an ACL graft in the knee, a person might feel that their knee is unstable, similar to how it felt before surgery. Any new or worsening symptoms should be reported to a healthcare provider promptly.
How Doctors Diagnose Graft Failure
Doctors use a combination of methods to determine if a graft is failing. The process often starts with a clinical assessment, which includes reviewing the patient’s symptoms and conducting a physical examination. This initial step helps guide further testing.
Laboratory tests are a common next step. Blood tests show how well a transplanted organ is functioning. For example, creatinine levels in the blood are checked to assess kidney function, while liver enzyme levels are monitored for liver grafts. These tests can also detect signs of inflammation or antibodies that may be attacking the graft.
Imaging studies allow doctors to look at the graft and surrounding area. An ultrasound can check blood flow and structure, while CT scans or MRIs provide more detail. For a definitive diagnosis, a biopsy is often performed. This involves examining a small sample of the graft tissue under a microscope to confirm rejection and determine its severity.
Approaches to Managing Graft Failure
The management of graft failure is tailored to the individual patient, depending on the cause of the failure, the type of graft, and the patient’s overall health. The goal is to address the underlying problem and preserve the function of the graft if possible.
If the failure is due to rejection, doctors may adjust or increase the patient’s immunosuppressive medications. When an infection is the cause, antibiotics are used to treat it. In some situations, surgical intervention may be necessary to fix technical issues, such as problems with blood vessels that supply the graft.
In cases where the graft has failed irreversibly, other options are considered. Supportive care can help manage symptoms and maintain the patient’s quality of life. For some, re-transplantation may be an option. If a failing graft is causing significant harm, it might need to be surgically removed.