CDA II / Congenital Dyserythropoietic Anemia

Hello everybody,

I'm Meenakshi from India. Do anybody has any info if Thalassemia and CDA II are similar or not ?

I did find this abstract on a study done, it looked at possibility of the two conditions (specifically Beta-Thal & CDA interacting):

http://www.ncbi.nlm.nih.gov/pubmed/2049466

I also found this comparison:

"Anemia in CDA is usually macrocytic as opposed to the microcytic anemia found in classical beta-thalassemia syndromes. Hemoglobin analysis in CDA may show an elevated Hb F, but most of the hemoglobin is Hb A, whereas in beta-thalassemia major or intermedia there is minimal or no Hb A." from https://online.epocrates.com/u/2935251/Beta+

I just want to say thank you for posting this question! We have been at a loss for why our other son has raised HgbF without any markers for Beta-Thal. This correlation and similarity between the two conditions makes me wonder what a CBC would look like for someone with CDA and severe iron def anemia - that sure would explain a lot in our little one's case. His brother w/no markers for Thal is closer to macrocytic RBC but still in normal ranges w/normal morph. I will have to keep this in mind if further questions come up about his diagnosis in the future.

Best wishes!

There are similarities in treatment, with blood transfusions and iron chelation therapy, as in thalassemia. CDA II is very rare and not genetically related to thalassemia.

Thanks to both of you for your response. Actually my son is diagnosed with CDA II at the age of 3 months :-( He's now 6 months old. He's been transfused thrice. Since last 2 months, his hb seems to be stable (8-8.5) & we've not gone for transfusion since then. Doctors say that it is similar to thalassemia. I'm actually not satisfied with the answer & there is very less info available on CDA cases. I wonder if it is as severe as thal major. Would appreciate if anybody can throw some light... I'm really worried about my son....

At present, Doctors have prescribed Prednisolone to be given daily.

Hope to hear something positive !!!

The severity of the anemia cannot be predicted. There is an in depth medical review of CDA II at http://bloodjournal.hematologylibrary.org/content/102/13/4576.full.htmlUpdated

The severity of the anemia is variable, with about 10% of patients in both Iolascon's and our series requiring regular red cell substitution in infancy and childhood, while others have only moderately decreased hemoglobin values throughout their life.

There is another article at http://ghr.nlm.nih.gov/condition/congenital-dyserythropoietic-anemia  that is a basic overview.

The anemia associated with CDA type II can range from mild to severe, and most affected individuals have jaundice, hepatosplenomegaly, and the formation of hard deposits in the gallbladder called gallstones. This form of the disorder is usually diagnosed in adolescence or early adulthood. An abnormal buildup of iron typically occurs after age 20, leading to complications including heart disease, diabetes, and cirrhosis.

Depending on the frequency of transfusions, chelation therapy may eventually be needed to remove the excess iron build up. This is made easier these days with the availability of oral chelation drugs. In this way, CDA II can be very much like thalassemia, as treatment is similar.

Hi Meenakshi

I am a haematologist and amongst other things look after patients with CDA in UK. This is quite a rare condition and clinically/technically classified as thalassemia intermedia. As a disease  it is very different to Thalassemia Major mainly due to genetic events associated with it . It is very important to establish the diagnosis as it can be very challenging. Also there are different sub types (type I, II, III etc) with different management strategies.
Very  recently working with a large north Indian hospital, we have identified around 30 children with this condition (almost all CDA II) . The main stay of treatment is splenectomy, blood transfusions and iron chelation. Steroids are  not used unless there are other complications.
I hope this is helpful.
Dr Ahmed
momin.ahmed@nhs.net

Thanks a lot Dr. Ahmed. My son has been diagnosed with CDA II & currently is on Prednisolone. He is of 6 months & since last 2.5 months his hemoglobin is stable around 8-8.5.

How removal of Spleen is helpful in this disease and what could be the implications of that in future ?

It is not possible to provide medical advise without a comprehensive review of medical information. However I can make some general observations

1) Steroids are not used in CDA unless there is some other issue (like alloimmunization  showing up as alloantibodies or autoantibodies). Just haemolysis is not a justification.
2) Splenectomy is useful in only CDA II. It is not at all useful in other CDAs. It is therefore important to establish the diagnosis  before anything like this is done especially as there are risks associated with removing spleen (chiefly immediate risk of surgical procedure and a long term risk of infections as immunity is suppressed). Infection risk is a bigger problem in south east Asian countries when compared to west. The earlier the spleen is removed the bigger the risk of infection.  It is for this reason that splenectomy only rarely (if at all) is performed under 5 years of age.

The defect in CDA II is that Red cells are not made as efficiently as they should be (ineffective erythropoiesis). However a bigger problem is that what is made, is rapidly broken down in spleen (haemolysis). Therefore removing spleen helps. In clinical practice about one gram or so Hb raise is seen after removal of spleen.

3) If his Hb is around 8 -8.5 I would be happy with this, as long as he is asymptomatic and growing well.
4) It is likely he will still need transfusions intermittently when having usually childhood infections etc (averaging 2-4 per year at 10-20 ml/ kg)
5) Although the iron will start creeping up after 10-20 transfusions rarely this is problem before the age of 3-5y even in regularly transfused children.
6) If this is CDA II then it really resembles hereditary spherocytosis more than thalassemia major. And this is a source of significant clinical confusion.

Finally if properly managed especially upto early teens, CDA II is compatible with a normal life span and more or less normal activity. Later in life, say late third decade, problems with iron overload are seen. These can been seen sooner in some cases (regular transfused, male, iron rich diets, poor chelation etc) .
I would be happy to communicate with your clinician if you think that would help. This is an ultra rare disorder (1-2 per 3-5 million cases) with really no experts around.
Best wishes
Momin Ahmed
momin.ahmed@nhs.net

Thanks much Dr. I would like to share his Bone marrow Test & HEMPAS test reports with you. Will send you those on ur email id. Hope I'm not bothering you.