Congenital dyserythropoietic anemia type I (CDA I) is a disorder of blood cell production, particularly of the production of

erythroblast A nucleated red blood cell (NRBC), also known by #Nomenclature, several other names, is a red blood cell that contains a cell nucleus. Almost all vertebrate organisms have hemoglobin-containing cells in their blood, and with the exception of mamm ...

s, which are the precursors of the

red blood cell Red blood cells (RBCs), referred to as erythrocytes (, with -''cyte'' translated as 'cell' in modern usage) in academia and medical publishing, also known as red cells, erythroid cells, and rarely haematids, are the most common type of blood cel ...

s (RBCs).Congenital dyserythropoietic anaemia type I
– Enerca (''European Network for Rare and Congenital Anaemias'') website

Presentation

Many affected individuals have yellowing of the skin and eyes (

jaundice Jaundice, also known as icterus, is a yellowish or, less frequently, greenish pigmentation of the skin and sclera due to high bilirubin levels. Jaundice in adults is typically a sign indicating the presence of underlying diseases involving ...

) and an enlarged liver and spleen (

hepatosplenomegaly Hepatosplenomegaly (commonly abbreviated HSM) is the simultaneous enlargement of both the liver (hepatomegaly) and the spleen (splenomegaly). Hepatosplenomegaly can occur as the result of acute viral hepatitis, infectious mononucleosis, and his ...

). This condition also causes the body to absorb too much iron, which builds up and can damage tissues and organs. In particular, iron overload can lead to an abnormal

heart rhythm ''Heart Rhythm'' is a peer-reviewed medical journal published by Elsevier that covers the study and management of cardiac arrhythmia. It is the official journal of the Heart Rhythm Society, the Cardiac Electrophysiology Society, and thPediatric & ...

(

arrhythmia Arrhythmias, also known as cardiac arrhythmias, are irregularities in the cardiac cycle, heartbeat, including when it is too fast or too slow. Essentially, this is anything but normal sinus rhythm. A resting heart rate that is too fast – ab ...

congestive heart failure Heart failure (HF), also known as congestive heart failure (CHF), is a syndrome caused by an impairment in the heart's ability to fill with and pump blood. Although symptoms vary based on which side of the heart is affected, HF typically pr ...

diabetes Diabetes mellitus, commonly known as diabetes, is a group of common endocrine diseases characterized by sustained high blood sugar levels. Diabetes is due to either the pancreas not producing enough of the hormone insulin, or the cells of th ...

, and

chronic liver disease Chronic liver disease in the clinical context is a disease process of the liver that involves a process of progressive destruction and regeneration of the liver parenchyma leading to fibrosis and cirrhosis. "Chronic liver disease" refers to diseas ...

(

cirrhosis Cirrhosis, also known as liver cirrhosis or hepatic cirrhosis, chronic liver failure or chronic hepatic failure and end-stage liver disease, is a chronic condition of the liver in which the normal functioning tissue, or parenchyma, is replaced ...

). Rarely, people with CDA type I are born with skeletal abnormalities, most often involving the fingers and toes.

Genetics

CDA type I, an autosomal recessive disorder, is transmitted by both parents and usually results from

mutation In biology, a mutation is an alteration in the nucleic acid sequence of the genome of an organism, virus, or extrachromosomal DNA. Viral genomes contain either DNA or RNA. Mutations result from errors during DNA or viral replication, ...

s in the '' CDAN1'' gene. Little is known about the function of this

gene In biology, the word gene has two meanings. The Mendelian gene is a basic unit of heredity. The molecular gene is a sequence of nucleotides in DNA that is transcribed to produce a functional RNA. There are two types of molecular genes: protei ...

, and it is unclear how mutations cause the characteristic features of CDA type I. Some people with this condition do not have identified mutations in the ''CDAN1'' gene, leading researchers to believe that mutations in at least one other gene can also cause this form of the disorder.congenital dyserythropoietic anemia
- Genetics Home Reference

Diagnosis

CDA type I is characterized by moderate to severe

anemia Anemia (also spelt anaemia in British English) is a blood disorder in which the blood has a reduced ability to carry oxygen. This can be due to a lower than normal number of red blood cells, a reduction in the amount of hemoglobin availabl ...

. It is usually diagnosed in childhood or adolescence, although in some cases, the condition can be detected before birth.

Treatment

Treatment consists of frequent

blood transfusions 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 ...

and

chelation therapy Chelation therapy is a medical procedure that involves the administration of chelating agents to remove heavy metals from the body. Chelation therapy has a long history of use in clinical toxicology and remains in use for some very specific medic ...

. Potential cures include

bone marrow transplantation Hematopoietic stem-cell transplantation (HSCT) is the transplantation of multipotent hematopoietic stem cells, usually derived from bone marrow, peripheral blood, or umbilical cord blood, in order to replicate inside a patient and produce a ...

and

gene therapy Gene therapy is Health technology, medical technology that aims to produce a therapeutic effect through the manipulation of gene expression or through altering the biological properties of living cells. The first attempt at modifying human DNA ...

References

External links

{{Medical resources , ICD10 = D64.4 , ICD9 = {{ICD9, 285.8 , Orphanet=98869 , DiseasesDB=29701 Genetic disorders with no OMIM Anemias