Thallaesemic patients are advised to have only "phenotypically matched blood".I mean the transfusion problems arise mainly due to "grouping problems" like mismatch b/w ABO & Rh+/- so what do this phenotyping mean? Isn't "grouping" of blood enough?

Statutory declaration- the link provided in the q is only to clarify in which context the q is asked & nothing more, like promoting Egyptian Gov. Health Service...(or any other CRAZY INTERPRETATIONS like that)**

  • 2
    $\begingroup$ This question appears to be off-topic because it is about a special process of the egyptian blood transfusion service, which we will not be able to answer. $\endgroup$
    – Chris
    Dec 7, 2014 at 17:55
  • 1
    $\begingroup$ excuse me....but I think you need to delve deeper into a q b4 u make such....naive comment.....Indian blood transfusion process also follows this....& if you really want to , then try to get through Wintrobe's Clinical Hematology (which is not possible for me at my stage).... $\endgroup$ Dec 7, 2014 at 18:00
  • $\begingroup$ I do not think this question should be closed since I know a similar advice is dispensed in many middle eastern countries! $\endgroup$ Dec 7, 2014 at 19:00

1 Answer 1


In response to the above q. many have commented that the process is only limited to Middle Eastern countries....I think the term 'only' will be better substituted by 'mainly', the reason to which , is explained later ....

Now, the main clarification lies in the fact that,

....there are more than 600 known antigens besides A and B that characterize the proteins found on a person's red cells. A combination of some of these less familiar but commonly occurring antigens are absent from the blood of an extremely small percentage of the population. There are also a few antigens that almost all people have on their red cells but that some lack. - One In A Million American Rare Donor Program

Now patients receiving a 1st time transfusion normally do not show any reactions or cross-matching problems with these blood subgroups but during repeated transfusion process like in case of thallaesemia , the receiver's blood gets sensitized against the donor's blood & the problems ensues...

Dr Therese Callaghan said, “All other antibodies are unexpected and are of two distinct types, alloantibodies (which target an antigen that is not present on your own red blood cells) and autoantibodies (which target an antigen that is present on your own cells).

“Patients receiving a transfusion for the first time do not normally have problems with matching blood types and antigens. However it is during subsequent transfusions when more care needs to be taken. If, during a later transfusion, the blood contains the same antigens as an earlier one, the patient’s immune system recognises the transfused blood cells as ‘foreign’ and the antibodies (formed after the first transfusion) will destroy the blood cells the patient has been given. This is called a transfusion reaction and can cause serious illness or even death if not treated quickly. That is why matching the blood phenotype is so important.”

Now coming to "Why mainly in Middle-East ??"

These rare blood groups are distributed into major 30 discrete system, which mainly are present in different ethnic groups & communities...mainly living in Middle-Eastern states & Asia...& also in African countries... http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3353626/table/T3/

Intersted people may also check the following articles (or simply search Google)

To Provide Phenotype-Matched Red Blood Cells or Not – That is the Question!

13.3: Pre-transfusion testing- Joint United Kingdom (UK) Blood Transfusion and Tissue Transplantation Services Professional Advisory Committee

& for a complete picture plz browse through- Immunohaematology


You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .