What Is Fanconi Anemia?
Fanconi anemia (FA) is different from Fanconi syndrome, a rare kidney disorder.
It is a rare disease passed down through families (inherited) that mainly affects the bone marrow. It results in decreased production of all types of blood cells. This is the most common inherited form of aplastic anemia.
This genetic disorder ultimately leads to bone marrow failure. Your bone marrow is responsible for making three different types of blood cells in your body. These include red blood cells, which bring oxygen to your tissues and organs, white blood cells, which fight infections, and platelets, which promote blood clotting to stop bleeding.
Causes of Fanconi Anemia
FA is a genetic disease that occurs when two people with the recessive gene have children. Recessive means that the gene only expresses itself when it has been inherited from both parents. FA is a complicated genetic disease. Nineteen different genes have been connected to FA. Abnormalities in those 19 genes account for 95 percent of FA cases.
Risk Factors for Fanconi Anemia
Any child with a family history of FA is at risk for developing the condition. However, Ashkenazi Jews and Afrikaners are much more likely than others to carry the recessive gene. Ashkenazi Jews are people of Eastern European Jewish descent, and Afrikaners are South Africans descended from Dutchmen who colonized South Africa in the 17th century.
Diagnosing Fanconi Anemia
One of the initial steps of diagnosis is investigating your family history. Since a recessive gene causes FA, parents might not be aware that they’re carriers. Your doctor will look for a history of family illnesses such as anemia, digestive disorders, and immune problems.
The methods used to conduct a genetic diagnosis of FA vary. A chromosome breakage test can be conducted using either skin cells or blood. A chemical will be combined with the cells. The cells’ chromosomes are analyzed under the microscope. The chromosomes of a person with FA will have very distinctive breakage.
Cytometric flow analysis, or flow cytometry, will analyze skin cells by mixing them with chemicals. If your cells react to the chemicals, it means that you likely have FA.
Mutation screening consists of using a skin cell sample to look for any defects in the 19 known genes associated with FA.
Screening for Fanconi Anemia Before Birth
Women who have a family history of FA should undergo genetic testing of their unborn baby. This can be done through amniocentesis and chorionic villus sampling (CVS).
In amniocentesis, a doctor uses a needle to remove fluid from the amniotic sac that contains the unborn baby. The fluid is tested for the presence of FA genes.
CVS involves inserting a tube through the vagina and cervix and using the tube to take tissue samples of the placenta. The tissue samples are then tested for the recessive FA gene. Chromosome breakage studies can also be performed using CVS.
If your child tests positive for the FA gene, they’ll be monitored for other signs of the condition. If your child is born with birth defects, their doctor will confirm an FA diagnosis with genetic testing.
Fanconi Anemia Treatments
FA is a genetic disease, and there’s no cure available. However, the symptoms of FA can be treated. Treatments for FA vary based on the seriousness of the condition and the age of the person affected.
Addressing anemia and other symptoms is the main focus of FA treatment. It’s useful to consider short-term and long-term treatment strategies.
Short-term treatment methods for FA can include:
- cancer or tumor screening
- antibiotics for any infections
- blood transfusions to increase the blood cell count
The goal of long-term treatment for FA is to improve quality of life and extend the lifespan of people who have this condition. Androgen therapy uses male hormones on an ongoing basis to increase the long-term production of blood cells. Man-made or naturally occurring growth substances can help your body make more blood cells. Surgery may be able to correct birth defects that occur in the arms, thumbs, hips, and other body parts.
Blood and Marrow Stem Cell Transplants
During a blood and marrow stem cell transplant, stem cells are taken from a healthy donor to replace the abnormal ones. The donor is usually a family member. Your bone marrow is destroyed using radiation or chemotherapy. Then, the new healthy marrow cells are injected into your bone, where they’ll grow and produce normal, healthy marrow and blood cells.
Symptoms of Fanconi Anemia?
FA is often diagnosed at birth or soon after because it affects the way your bone marrow produces blood cells. When you don’t have a sufficient number of blood cells you’ll begin to experience the following:
Aplastic anemia is characterized by a lack of energy due to low numbers of red blood cells, which help to oxygenate your blood. The symptoms of anemia include dizziness, headaches, and an inability to keep your hands and feet warm.
Certain types of birth defects will indicate that your infant has FA, including:
- bone defects, especially involving the thumbs and arms
- eye and ear defects
- skin discoloration
- kidney problems
- congenital heart defects
Developmental problems can include:
- a smaller-than-normal height
- low birth weight
- poor appetite
- delayed growth
- a smaller-than-normal head size
- intellectual disability
Symptoms in Adults
Adults who are diagnosed later in life will usually experience a completely different set of symptoms. The symptoms in adults will usually affect the sexual organs or the reproductive system. The symptoms in women include:
- periods that occur later than normal
- early menopause
- smaller-than-normal genitals
- fertility issues
- frequent miscarriages
Men with FA may experience fertility issues and have smaller-than-normal genitals.
There are normally physical signs of this condition at birth, but some children with FA don’t show signs of FA until later in life. According to the Fanconi Anemia Research Fund, more than 60 percent of patients born with FA have at least one physical anomaly. The median lifespan for people with FA is 29 years, although some people live into their 50s.
Children with FA are commonly diagnosed with acute myeloid leukemia and myelodysplastic syndrome between the ages of 5 and 15.
When people with FA become adults, they’re at an increased risk of developing a wide range of cancers, including oral and bone cancers.
Fanconi Anemia Complications
Fanconi Anemia is very serious and has lifelong complications, which can include:
Anemia is caused by a low red blood cell (RBC) count.
Birth defects connected to Fanconi anemia can include:
- defects of the ear, which may cause children with FA to be born deaf
- skin discoloration
- kidney problems, such as a missing kidney
- bone or skeletal defects
- defects of the eye
- congenital heart defects, the most common of which is a hole or defect in the lower wall that separates the left and right chambers of the heart, or a ventricular septal defect
Up to 10 percent of people with FA develop leukemia. People with FA may also develop cancerous tumors in their mouths.
FA is a recessive gene disorder. This means your parents both have to have the defective FA gene for you to develop FA.