Bone marrow transplants are complicated procedures that carry significant risks of serious complications.
Generally risks are reduced if:
- you are young - studies have shown the younger you are, the more likely the treatment is to succeed
- you receive a donation from a brother or sister
- you have no other serious health conditions, apart from the condition that you are being treated for
As there is a significant risk of complications occurring after a bone marrow transplant, it is important you are fully aware of both the risks and possible benefits before treatment begins. You may wish to discuss these with your treatment team and your family.
The major problem with stem cell transplants is the recipient's ability to withstand high doses of chemotherapy (and sometimes radiotherapy) often needed before the transplant.
Many conditions for which a bone marrow transplant is required affect older people. An autologous transplant (where the patient's own stem cells are used) is generally considered less risky than an allogeneic transplant (where a donor's stem cells are used).
Therefore, the upper age limit at most centres is around 55 years of age for an allogeneic transplant and 60-70 years for an autologous transplant.
The main risks associated with a bone marrow transplant are discussed below.
Graft versus host disease
In some cases, the transplanted cells (graft cells) recognise the recipient's cells as 'foreign' and try to attack them. This is known as graft versus host disease (GvHD) and it often occurs following stem cell transplantation.
There are two types of GvHD. They are:
- acute GvHD - which usually happens during the first three months of the transplant
- chronic GvHD - which develops from acute GVHD and can cause symptoms for many years
The symptoms of acute GvHD include:
- red spots on the hands, feet and face which then spread across the body into a rash
- the rash may then develop into blisters
- a high temperature (fever) of 38C (100.4F) or above
- bloody or watery diarrhoea
- stomach cramps
- jaundice - yellowing of the skin and whites of the eyes (although this is a rare symptom of acute GvHD)
Chronic GvHD can develop anywhere between three months and two years after the transplant. The symptoms can persist or they may come and go for many years. They can range in severity from mild to life-threatening.
Symptoms of chronic GvHD include:
- an itchy, dry rash that can spread over the entire body
- dry and sensitive mouth
- dry eyes
- hardening of the skin
- hair loss
In particularly serious cases of GvHD, lung or liver function can be affected which can be very serious.
GvHD can be treated using immunosuppressants, usually in conjunction with corticosteroids (see below).
Immunosuppressants stop the transplanted tissue releasing antibodies that would otherwise attack the rest of your body. However, they will also affect the rest of your immune system, placing you at a higher risk of infection.
Corticosteroids are a type of medication that contain powerful hormones. They can help suppress (control) the exaggerated immune response that leads to GvHD. However, corticosteroids can cause a number of side effects including:
- high blood sugar levels
- increased appetite
- mood changes
- vomiting
- diarrhoea
- itchiness
- high blood pressure (hypertension)
Infection
After having a bone marrow transplant, your risk of developing an infection will be increased. This is because the conditioning you receive before the transplant will weaken your immune system. The risk of infection may be further increased if you need to take immunosuppressants.
It is very important to prevent infections developing. If you get an infection it could quickly develop into a more serious condition such as a lung infection (pneumonia).
