Congenital dyserythropoietic anemia (CDA) is a rare blood disorder, similar to the
thalassemia
Thalassemias are inherited blood disorders characterized by decreased hemoglobin production. Symptoms depend on the type and can vary from none to severe. Often there is mild to severe anemia (low red blood cells or hemoglobin). Anemia can resul ...
s. CDA is one of many types of
anemia
Anemia or anaemia (British English) is a blood disorder in which the blood has a reduced ability to carry oxygen due to a lower than normal number of red blood cells, or a reduction in the amount of hemoglobin. When anemia comes on slowly, ...
, characterized by
ineffective erythropoiesis Ineffective erythropoiesis is active erythropoiesis with premature death of red blood cells, a decreased output of RBCs from the bone marrow, and, consequently, anemia.
It is a condition characterised by the presence or abundance of dysfunctional p ...
, and resulting from a decrease in the number of
red blood cells (RBCs) in the body and a less than normal quantity of hemoglobin in the blood.
[ CDA may be transmitted by both parents autosomal recessively or dominantly.
]
Signs and symptoms
The symptoms and signs of congenital dyserythropoietic anemia are consistent with:
* Tiredness
Fatigue describes a state of tiredness that does not resolve with rest or sleep. In general usage, fatigue is synonymous with extreme tiredness or exhaustion that normally follows prolonged physical or mental activity. When it does not resolve ...
(fatigue)
* Weakness
Weakness is a symptom of a number of different conditions. The causes are many and can be divided into conditions that have true or perceived muscle weakness. True muscle weakness is a primary symptom of a variety of skeletal muscle diseases, i ...
* Pale skin
Types
Congenital dyserythropoietic anemia has four different subtypes, CDA Type I, CDA Type II, CDA Type III, and CDA Type IV
Congenital dyserythropoietic anemia type IV (CDA IV) has been described with typical morphologic features of CDA II but a negative acidified-serum test. Presentation
CDA type IV is characterized by mild to moderate splenomegaly. Hemoglobin is ver ...
. CDA type II (CDA II) is the most frequent type of congenital dyserythropoietic anemias.
Diagnosis
The diagnosis of congenital dyserythropoietic anemia can be done via sequence analysis of the entire coding region, types I, II, III and IV ( is a relatively new form of CDA that had been found, just 4 cases have been reported[) according to the genetic testing registry.
]
Treatment
Treatment of individuals with CDA usually consist of frequent blood transfusion
Blood transfusion is the process of transferring blood products into a person's circulation intravenously. Transfusions are used for various medical conditions to replace lost components of the blood. Early transfusions used whole blood, but m ...
s, but this can vary depending on the type that the individual has. Patients report going every 2–3 weeks for blood transfusions. In addition, they must undertake chelation therapy to survive; either deferoxamine, deferasirox, or deferiprone to eliminate the excess iron that accumulates. Removal of the spleen and gallbladder[ are common. Hemoglobin levels can run anywhere between 8.0 g/dl and 11.0 g/dl in untransfused patients, the amount of blood received by the patient is not as important as their baseline pre-transfusion hemoglobin level. This is true for ferritin levels and iron levels in the organs as well, it is important for patients to go regularly for transfusions in order to maximize good health, normal ferritin levels run anywhere between 24 and 336 ng/ml, hematologists generally do not begin chelation therapy until ferritin levels reach at least 1000 ng/ml. It is more important to check iron levels in the organs through MRI scans, however, than to simply get regular blood tests to check ferritin levels, which only show a trend, and do not reflect actual organ iron content.][
]
Gene therapy
Gene therapy
Gene therapy is a medical field which focuses on the genetic modification of cells to produce a therapeutic effect or the treatment of disease by repairing or reconstructing defective genetic material. The first attempt at modifying human D ...
, as well as, bone marrow transplant are also possible treatments for the disorder, but each have their own risks at this point in time. Bone marrow transplantation is the more used method between the two, whereas researchers are still trying to definitively establish the results of gene therapy treatment. It generally requires a 10/10 HLA matched donor, however, who is usually a sibling. As most patients do not have this, they must rely on gene therapy research to potentially provide them with an alternative. CDA at both clinical and genetic aspects are part of a heterogeneous group of genetic conditions. Gene therapy is still experimental and has largely only been tested in animal models until now. This type of therapy has promise, however, as it allows for the autologous transplantation of the patient's own healthy stem cells rather than requiring an outside donor, thereby bypassing any potential for graft vs. host disease
Graft-versus-host disease (GvHD) is a syndrome, characterized by inflammation in different organs. GvHD is commonly associated with bone marrow transplants and stem cell transplants.
White blood cells of the donor's immune system which remain wi ...
(GVHD).
In the United States, the FDA approved clinical trials on Beta thalassemia patients in 2012. The first study, which took place in July 2012, recruited human subjects with thalassemia
Thalassemias are inherited blood disorders characterized by decreased hemoglobin production. Symptoms depend on the type and can vary from none to severe. Often there is mild to severe anemia (low red blood cells or hemoglobin). Anemia can resul ...
major,
See also
* Thalassemia
Thalassemias are inherited blood disorders characterized by decreased hemoglobin production. Symptoms depend on the type and can vary from none to severe. Often there is mild to severe anemia (low red blood cells or hemoglobin). Anemia can resul ...
* Hemoglobinopathy
* List of hematologic conditions
:''This is an incomplete list, which may never be able to satisfy certain standards for completion.''
There are many conditions of or affecting the human hematologic system—the biological system that includes plasma, platelets, leukocytes, and ...
References
Further reading
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External links
{{Diseases of RBCs
Genetic disorders with no OMIM
Red blood cell disorders
Anemias