5 important facts about graft-versus-host disease

Graft-versus-host disease is a complication that can occur after a procedure called an allogenic stem cell transplant. This procedure involves taking stem cells called hematopoietic stem cells from the bone marrow of a donor and transplanting them to the bone marrow of a host. This is done to replace hematopoietic stem cells that have become diseased and is a treatment option for certain cancers (specifically, certain types of leukemias and lymphomas) and other serious illnesses.

Hematopoietic stem cells are immature cells that divide and then grow into different types of blood cells—red blood cells, platelets, and white blood cells. When transferred to a different body, they begin making new blood cells. GVHD occurs when newly formed white blood cells begin attacking organs and tissues inside their new host.

Here, we look at five important facts to help better understand GVHD.

Mild GVHD can be a good sign

The purpose of an allogenic stem cell transplant is to rebuild an immune system that has become diseased. In that regard, mild GVHD can be a good thing—it’s a sign that the transplant is working and that the body is making new white blood cells. It can also be a sign that the immune system is killing off any remaining cancer cells.

Acute GHVD is common

Roughly half of people who received an allogenic stem cell transplant develop what is known as classic acute GVHD (a type of GVHD that typically occurs within the first 100 days following the transplant). Others develop different types of the disorder, such as classic chronic GVHD, which occurs after the first 100 days following a transplant—sometimes even years later.

GVHD symptoms vary by type

In addition to occurring at different times, classic acute GVHD and classic chronic GVHD are associated with different symptoms and affect different parts of the body.

• Classic acute GVHD typically involves the skin, mouth, the gastrointestinal tract, and the liver. Skin rash, abdominal pain, diarrhea, nausea, vomiting, dark urine, and yellowing of the skin and eyes (jaundice) are common symptoms.
• Classic chronic GVHD involves a wider range of organs and tissues, including the skin, mouth, liver, lungs, reproductive organs, and digestive system. It causes dryness, ulcers, and changes to the skin as well as the inner linings of the body.
• In some cases, a person can have symptoms of both acute and chronic GVHD, which is called overlap syndrome.
• Acute GVHD typically begins in the first 100 days following a transplant, but there is also persistent, recurrent, late-onset GVHD, which causes acute-associated symptoms but begins after 100 days.

GVHD will be confirmed with tests

Your healthcare team may suspect GVHD based on your symptoms and when those symptoms began, but they will need to confirm the diagnosis. Depending on your symptoms, this may involve imaging tests, biopsies (which may test tissue samples from the skin, liver, or bowel), lung function tests, and blood work. This may seem like a lot to go through—especially when you have already been through a stem cell transplant—but these tests are necessary to give you the best treatment possible.

GVHD is treatable

Treating GVHD typically involves medications that act on the immune system, such as corticosteroids and immunosuppressive drugs. Sometimes these are medications you are already taking following an allogenic STC that are taken in different doses. Sometimes these are different medications. Treatment will depend on the type of GVHD a person has, the symptoms it is causing, and the severity of those symptoms.