Congenital dyserythropoietic anemia

Congenital dyserythropoietic anemia (CDA) is a rare group of inherited blood disorders that affects the development of red blood cells. In people with CDA, immature red blood cells do not develop into normal, mature cells. As a result, affected individuals have a significant reduction in the number of functional red blood cells (anemia). The term "dyserythropoietic" refers to the abnormal red blood cell shape that occurs in people with this condition. People with CDA typically have mild to moderate anemia. In some cases, affected individuals have severe anemia that may require frequent blood transfusions to replenish the supply of red blood cells.

The signs and symptoms of CDA can include tiredness (fatigue), weakness, yellowing of the skin and eyes (jaundice), and an enlarged liver and spleen (hepatosplenomegaly). CDA also causes the body to absorb too much iron (iron overload), which can damage tissues and organs.

There are multiple types of CDA. Each type has a different genetic cause and distinct but overlapping patterns of signs and symptoms.

CDA type I is characterized by moderate to severe anemia that typically begins in childhood or adolescence, although the condition can be detected before birth in some cases. In addition to the signs and symptoms common to all types of CDA, individuals with CDA type I can have skeletal issues, including short stature or abnormalities of the fingers or toes.

The anemia associated with CDA type II can range from mild to severe, and it usually develops in adolescence or early adulthood. Individuals with CDA type II may develop hard deposits in the gallbladder called gallstones in addition to the usual signs and symptoms of CDA.

CDA type III can result in anemia that ranges from mild to severe, depending on the genetic cause, and typically begins in infancy or childhood. Some people with CDA type III do not receive a diagnosis until later in life because they have very mild symptoms. In some cases, individuals with CDA type III develop a blood disorder known as monoclonal gammopathy, which can lead to a cancer of white blood cells (multiple myeloma). Some people with CDA type III have eye abnormalities that can cause vision impairment.

CDA type IV is characterized by moderate to severe anemia that typically develops early in life, although the condition can be detected before birth in some cases. Affected individuals can have extensive swelling caused by fluid accumulation before birth (hydrops fetalis). In addition to the signs and symptoms that are common to all types of CDA, individuals with CDA type IV often have short stature.