How Is Fanconi Anemia Treated?
Doctors decide how to treat Fanconi anemia (FA)
based on a patients age and how well (or how poorly) the patients
bone marrow is producing new blood cells.
Goals of Treatment
Long-term treatments for FA can:
- Cure the anemia. Damaged bone marrow cells are
replaced with healthy ones that can make enough of all three types of blood
cells on their own.
- OR
- Treat the symptoms without curing the cause. This
is done using medicines and other substances that can help your body make more
blood cells for a limited time.
Observation and Short-Term Treatment
If you or your child has FA, but your bone marrow is
still able to make many of the new blood cells your body needs, your doctor may
perform frequent blood count checks. During this period of observation, your
doctor will probably want you to have bone marrow exams once a year. Your
doctor also will screen you closely for any signs of cancer or tumors.
If your blood counts begin to drop sharply and stay
low, your doctor may assume your bone marrow is failing. He or she may give you
antibiotics to help your body fight infections.
In the short term, your doctor also may want to give
you blood transfusions to increase your blood cell counts to normal levels.
However, long-term use of blood transfusions can reduce the chances that other
treatments, which can help your body make enough blood cells on its own, will
work.
Long-Term Treatment
There are four main types of long-term treatment for
FA:
- Bone marrow transplant
- Androgen therapy
- Synthetic growth factors
- Gene therapy
Bone Marrow Transplant
Bone marrow transplant, also called stem cell
transplant, is the current standard treatment for patients with FA that's
causing major bone marrow failure. Healthy bone marrow cells from another
person, called a donor, are used to replace the abnormal cells in your bone
marrow.
Bone marrow transplant is most successful in younger
people who have few or no serious health problems, a brother or sister donor,
and few or no previous blood transfusions.
Successful bone marrow transplants will allow your
body to make enough of all three types of blood cells to work normally.
However, if you've had a transplant to treat FA, you will still be at risk for
some types of blood cancer and for developing cancerous solid tumors. Your
doctor will check your health regularly and often after the procedure.
Finding a donor. A key factor for
bone marrow transplant success is finding a donor whose bone marrow cells your
body won't reject. Your body is more likely to accept cells that can work with
your own cells without causing unhealthy side effects. If the new cells don't
match, your body's immune system may attack and destroy them. This is similar
to how the body responds when it's invaded by something from the outside, like
a virus or bacteria.
To determine whether a donor's cells will work with
yours, your doctor will use a blood test called HLA typing. This test looks at
proteins on the surface of blood cells. The proteins are called human leukocyte
antigens (HLA). Your blood and the donor's blood are tested, and the HLA
antigens on the blood cells are compared. If your HLA is similar to the
donor's, it means your body is less likely to try to fight and destroy the
donor's cells.
The greatest chance (up to 80 percent) for a
successful bone marrow transplant generally is if your brother or sister
donates bone marrow and if you and your sibling have matching HLA.
It's possible to have a successful bone marrow
transplant from a donor who isn't related to you, but success rates for this
type of transplant are less than 50 percent. It's also possible to have a
successful transplant using cells from umbilical cord blood. Because these
types of transplants are riskier, doctors only use cells from nonrelated donors
for transplants:
- If you have cancer (leukemia or myelodysplastic
syndrome)
- If you have no HLA-matched brother or sister to
donate cells
- If your body can't tolerate other treatments for
bone marrow failure
Receiving the transplant. Bone
marrow transplants are done in special units in hospitals to try to protect the
person receiving the transplant from infections. Before the transplant, you
receive high doses of chemotherapy, radiation therapy, or both. These
treatments destroy the abnormal bone marrow that isn't producing blood cells.
A sample of bone marrow is taken from the donor and
given to you through a vein. The donated bone marrow cells travel to your bone
marrow and start to make healthy blood cells. If the transplant is successful,
the new bone marrow cells multiply and begin making new, healthy blood cells
within 3 to 4 weeks.
Possible complications. After a
bone marrow transplant, you may be in the hospital for weeks or months. During
this time, you're isolated and closely watched for infections and other
complications. Complications are most likely to occur in the first 100 days
after a transplant.
Complications after bone marrow transplant include:
- Rejection of the new cells
- A condition called graft rejection
- A condition called graft-versus-host disease
(GVHD)
Graft rejection occurs when your immune system
destroys the new bone marrow cells. This occurs in 5 to 10 percent of people
who get bone marrow transplants. It's more likely to happen in people who have
had several transplants.
GVHD happens when the new white blood cells, created
by the donated bone marrow cells, attack your body. Signs and symptoms include
skin inflammation, severe diarrhea, and liver disease. GVHD can occur soon
after transplant, or it can develop slowly and can last for months or years.
GVHD most often happens in older people and those who receive unmatched
transplants.
To help prevent GVHD, the donor marrow is sometimes
treated, or you may get medicines that suppress the immune system after the
transplant. Sometimes symptoms of GVHD are treated with medicines such as
steroids.
Androgen Therapy
Before improvements made bone marrow transplants
more effective, androgen therapy was the standard treatment for people with FA.
Androgens are artificial male hormones that can help your body make more blood
cells for long periods.
Androgens are effective in increasing your red blood
cell count. They also help to increase your platelet count. They're less
effective in making more white blood cells in your body.
Unlike bone marrow transplant, androgens don't
enable your bone marrow to produce enough of all three types of blood cells on
its own. You may need ongoing treatment with androgens to control the effects
of FA. Also, androgens eventually lose their ability to help your body make
more blood cells, which means you will need other treatments.
Androgen treatment can have serious side effects,
such as liver disease, and it can't prevent you from developing leukemia.
Synthetic Growth Factors
Your doctor may choose to treat your FA with
substances known as growth factors. These are substances found in your body,
but they also can be man-made. They help your body make more red and white
blood cells. Growth factors that can help your body make more platelets are
still being researched. One of the more common growth factors used to treat FA
is called EPO, or erythropoietin (e-RITH-ro-PO-e-tin). EPO has some risks.
Based on your situtation, your doctor will decide whether EPO's benefits
outweigh its risks.
More research is needed on growth factor treatment
for FA. Early results suggest that growth factors may have fewer and less
serious side effects than androgens.
Gene Therapy
Researchers are looking for ways to replace abnormal
FA genes with normal, healthy genes. They believe that the replacement genes
will be able to make the proteins needed to repair and protect your bone marrow
cells.
Gene therapy uses viruses that have been altered so
that they can deliver normal genes to replace abnormal ones in FA patients'
bone marrow stem cells.
Early results hold promise, but this form of
treatment for FA is still in the experimental stage.
Surgery
Surgery may be needed to improve the use of arms,
thumbs, hips, legs, and other parts of the body that are malformed or
underdeveloped due to birth defects caused by FA.
If your child is born with a heart defect linked to
FA called
ventricular
septal defect, he or she may need surgery to close the hole in the heart's
wall so the heart can function normally.
Children with FA also may need surgery to correct
problems in the digestive system that can harm their nutrition, growth, and
survival. One of the most common problems is an FA-related birth defect where
the windpipe (trachea), which carries air to the lungs, is connected to the
esophagus, which carries food to the stomach. This can cause serious breathing,
swallowing, and eating problems and can lead to lung infections. Surgery is
needed to separate the two organs to allow normal eating and breathing.
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