Graft-versus-host disease or GVHD is a term used to describe a battle between the transplanted stem cells and the patient’s body. This is a complication that occurs when the new stem cells (the graft) reject or see your body (the host) as foreign.
While GVHD is extremely rare in autologous transplants, it occurs in approximately 50% of patients who have an allogeneic (donor) transplant. GVHD is less likely to occur if the donor and recipient are matched – have identical tissue or “HLA” types. The condition is considerably more common when the match is only partial or if the donor and recipient are unrelated. All patients receiving bone marrow from a donor, unless the donor is an identical twin, will receive drugs to try to prevent GVHD.
Of those who develop GVHD, many will experience only minor difficulties. About half will experience significant problems. There are two types of GVHD: acute and chronic.
Acute GVHD may occur early when the bone marrow starts to engraft around two to four weeks after the transplant. Acute GVHD may involve three main body systems:
Skin GVHD usually shows up as a rash anywhere on the skin surface but it is mostly seen on the hands, feet, abdomen and face. The skin initially looks sun-burnt. The rash may progress to other areas of the body and potentially become a blister-like rash.
Liver GVHD become evident in your bloodwork. Bloodwork is done regularly to test how your liver is functioning. With liver GVHD, these results become elevated. Liver GVHD may also cause the patient to become jaundiced (to have a yellow tone to the skin).
Gastrointestinal Tract GVHD appears as nausea and vomiting and/or acute, watery or sometimes explosive diarrhea. The amount of diarrhea can indicate the severity of the GVHD. An exam of the gastrointestinal tract is also done to confirm GVHD.
Chronic GVHD occurs after 100 days post-BMT. It may develop as a continuation of acute GVHD or occur without any prior history of acute GVHD. Chronic GVHD is usually less serious. It is most frequently associated with soreness or dryness of the mouth or eyes, lung and liver complications, changes in skin pigmentation. It may also cause hair loss, weight loss, vaginal dryness, cough, shortness of breath and joint problems.
To manage and treat GVHD, a number of drugs such as cyclosporine, methotrexate and prednisone are used early on to help prevent or minimize GVHD. However, some side effects of the drugs can interfere with the patients’ quality of life. Your BMT doctor will discuss these with you in detail.
GVHD is not always a negative development following a blood and bone marrow transplant. This is because the immune system that attacks the host causing GVHD is also known to attack cancer cells. Researchers have found that patients with GVHD generally have a lower risk of having a relapse of their cancer.