Congenital Sideroblastic Anemia | Symptoms & Causes
What are the symptoms of congenital sideroblastic anemia?
The symptoms and signs of CSA in children are primarily related to the anemia and its severity:
Some forms of CSA are associated with other symptoms or signs outside the blood system. These are referred to as syndromic CSAs. The associated symptoms can include:
- developmental delay
- deafness
- vision loss
- muscle dysfunction (heart muscle and/or other muscles)
- organ failure (e.g. kidney and/or liver)
- immunodeficiency
- fevers
- acidosis
What are the causes of CSA?
Each of the CSA types require testing to isolate. It is important to understand that some symptoms of CSA may resemble those of other more common medical problems or other blood disorders. Because some of these symptoms can also point to other conditions and because anemia itself can be a symptom of another medical problem, it’s important to have your child evaluated by a qualified medical professional for an accurate diagnosis and prompt treatment.
Congenital Sideroblastic Anemia | Diagnosis & Treatments
How is congenital sideroblastic anemia diagnosed?
The specific CSA diagnosis relies on an experienced clinician trained to recognize the characteristics of the anemia (e.g., red blood cell size: microcytic, normocytic, or macrocytic), the age of child (or adult) when symptoms are first noticed, and other potential symptoms (such as muscle weakness).
CSAs are usually diagnosed with:
- blood tests, including a complete blood count
- bone marrow examination
- body iron measurements (by laboratory testing, radiology/imaging and/or biopsy of the liver)
- molecular testing (gene sequencing, protein studies, etc)
After all tests are completed, the hematologist will be able to outline the best treatment options.
What are the treatments for CSA?
Depending on the specific type of a child’s CSA and the severity of the condition, a hematologist may recommend a variety of different treatments.
Medical therapy
X-linked sideroblastic anemia (XLSA) can sometimes respond very favorably to treatment with vitamin B6. Unfortunately, none of the other CSAs are known to respond to vitamins or other medical therapies.
Transfusion therapy
Blood transfusions may be given to treat severe anemia. Some children with CSAs may receive repeated blood transfusions to keep their hemoglobin level high enough to perform routine activities.
Iron chelators
CSAs can result in gradual iron overload related to increased daily iron absorption from the gut. Children who have repeated red blood cell transfusions or require chronic transfusions can also quickly become iron overloaded. Without removal of this iron, through chelators, it can build up and become toxic to several vital organs. Children may take chelators orally or by injection in order to remove excess iron from the body.
Stem cell transplant
Right now, the only cure for some CSAs is a stem cell transplant from another person (donor) to your child. The best transplant outcomes are almost always when the donor is a healthy sibling with compatible stem cells. The stem cells replace the diseased stem cells and restore normal blood production. In the syndromic sideroblastic anemias, disease manifestations unrelated to the bone marrow disease do not get better after bone marrow transplantation.
Because stem cell transplant also carries risk, it is recommended that children with a compatible full-sibling donor meet with a pediatric stem cell doctors to learn more about the process.
What is the long-term outlook for children with CSA?
The long-term outlook for children with CSA depends heavily on the specific type of CSA. A child with CSA will need regular follow-up care by a hematologist.
How we care for CSA
Children and adolescents with CSA are treated at Dana-Farber/Boston Children’s Cancer and Blood Disorders Center through our Rare Anemias and Iron Disorders Program. Our Rare Anemias and Iron Disorders Program provides comprehensive care for children with all types of rare anemias and iron disorders, as well as ongoing medical management and access to new treatment approaches through our clinical research.
