Diamond-Blackfan anemia: A genetic condition affecting the bone marrow that leads to anemia (low numbers of red blood cells) and often, birth defects. It affects five to 10 out of every million babies born in the U.S. A number of genetic mutations have been identified that can cause Diamond-Blackfan anemia, and it is inherited in an autosomal dominant pattern, meaning that only one copy of the defective gene is needed to cause the disorder. In about 45% of cases, those affected inherit a defective gene from one parent. In the remaining cases, a new mutation (change in the gene) occurs in people who do not have the condition in their family.
Symptoms and signs of Diamond-Blackfan anemia usually are seen during the first year of life and relate to the anemia and shortage of oxygen delivery to tissues from the low numbers of red blood cells. These symptoms include pallor, fatigue, and weakness. People with this disorder are at increased risk for developing myelodysplastic syndrome, another bone marrow disorder, acute myeloid leukemia (AML), and a type of bone cancer known as osteosarcoma. The birth defects that can accompany the bone marrow disorders are seen in about half of those affected and can vary in severity. Associated birth defects can include small head size (microcephaly); wide-set eyes (hypertelorism); droopy eyelids (ptosis); a low frontal hairline; a broad, flat bridge of the nose; small, low-set ears; and small lower jaw (micrognathia). Cleft palate and/or cleft lip may also be present. Slow growth, eye problems, and kidney problems are sometimes associated with the condition. Red blood cell transfusions and corticosteroid medications are the main treatments for Diamond-Blackfan anemia. Stem cell transplants have been performed successfully in some children with the condition.