Diamond Blackfan Anemia
Diamond Blackfan anemia (DBA) is a rare blood disorder that is usually diagnosed in children during their first year of life. Children with DBA do not make enough red blood cells–the cells that carry oxygen to all other cells in the body.
|Anatomy of Bone and Marrow (Click Image to Enlarge)
Blood cells are made in the bone marrow, the spongy insides of long bones. In children with DBA, many of the cells that would have become red blood cells die before they develop.
Facts about DBA
There are around 30 new cases of DBA every year in the United States and Canada. Boys and girls of all races are equally affected. Most of the time, signs or symptoms of anemia appear by 2 months of age, and the diagnosis of DBA is usually made in the first year of life.
DBA may be passed down through families. In about half the children diagnosed with the disorder, an abnormal gene has been identified and may contribute to the cause of DBA. In the other half of children with DBA, no abnormal genes are found and the cause is not known.
Treatment may include medications, blood transfusions, and bone marrow transplantation. DBA was once thought of as a disease only of children. With more successful treatments, however, many children survive well into adulthood, and many more adults now are living with the disease.
Symptoms of DBA
These are signs and symptoms of this type of anemia:
In addition to these signs and symptoms, up to half of children with DBA are also born with some type of birth defect. These may include abnormalities of the face, head, hands (especially the thumbs), heart, kidney, or genital area.
A diagnosis of DBA usually begins when your child's doctor finds signs or symptoms of anemia during a routine exam or after a routine blood test. The two most important tests for diagnosing DBA are blood sample testing and bone marrow testing. Findings needed to make the diagnosis are:
Anemia before 1 year of age
Blood sample showing that the type of anemia is macrocytic, which means red blood cells are larger than normal
Normal number of white blood cells and platelets in the blood sample
Not enough reticulocytes, which are newly made red blood cells
Bone marrow sample showing few cells that will develop into red blood cells
Other findings that support a diagnosis of DBA include family history, gene abnormalities, and birth defects.
Treatment of DBA
Here are some of the most common treatments for this anemia:
Steroids. These are strong drugs that fight inflammation in the body. Although doctors don't know exactly how they work in DBA, steroids allow about 80 percent of people with DBA to start making more red blood cells.
Blood transfusions. Healthy, matched donor blood may be given every four to six weeks to increase the amount of red blood cells in a person with DBA.
Stem cell transplant. Stem cells are cells in the bone marrow that can become all types of blood cells. Stem cell transplant involves finding a matched donor, usually a close family member, and transfusing their healthy stem cells into the person with DBA. Stem cell transplant may cure DBA, but rejection or infection is possible. Because these risks are serious, stem cell transplant is usually not used unless steroids or blood transfusions do not help.
About 20 percent of people with DBA go into remission after treatment. Remission means that the signs and symptoms of anemia have disappeared for more than six months without any treatment. Remission can last for many years and can even be permanent. If symptoms come back after remission, it is called relapse.
Severe anemia in a child affects the whole family. Treatment and management requires a complete caregiving team that includes medical specialists, as well nursing, nutritional, social, and psychological support. Parents or guardians should learn as much as they can about DBA and work closely with the treatment team.
Adults with DBA will need continued care and treatment, including managing the side effects of steroid treatment and repeated transfusion. Adults with DBA will also need to talk with their medical team about the risks of having children. A mother or father with DBA has about a 50 percent chance of passing DBA to a child. Pregnancy can also trigger a relapse in a woman whose DBA is in remission. A woman with DBA who is pregnant should be seen by a specialist in high-risk obstetrics.
A common complication of DBA is iron overload, which can affect the heart and liver. It results from the transfusions required for treatment. Treatment may include iron chelation drugs that remove iron from the blood to prevent complications. Steroids can have significant side effects, such as osteoporosis, weight gain, high blood pressure, and diabetes mellitus, all of which need to be monitored no matter the age of the patient. Younger patients are at particular risk for slowed physical growth. They may need a change in their treatment plan to ensure adequate growth in the first year of life.