Malcolm Needs

Sorry Neil, but I have to point out that this is not completely accurate.  Any red cell antigens that are adsorbed onto the red cell surface, rather than being an integral part of the red cell membrane remain the type of the patient, rather than the donor.  This is true of the Lewis phenotype (for instance, if the recipient was Le[a+b-], and the donor was Le[a-b+], after the transplant, the red cells will group as Le[a+b-], and not as Le[a-b+]}.  This is also true of antigens within the Chido/Rodgers Blood Group System, and certain others.

If the recipient is a Secretor, they will continue to secrete ABO substance of the original ABO type, which, of course, will also be adsorbed onto the red cell surface (as well as being in the plasma, leading to the phenomenon of "accommodation", and this is why most recipients stay with a reverse group of "AB" after an ABO mis-matched stem cell/bone marrow transplant.

SORRY TO BE A PEDANT, PARTICULARLY AS I AGREE WITH EVERYTHING ELSE YOU HAVE WRITTEN!

Thanks Malcolm. Not pedantry at all. These exceptions are relevant and potentially important, particularly for ABO.

Sorry Neil, but I have to point out that this is not completely accurate.  Any red cell antigens that are adsorbed onto the red cell surface, rather than being an integral part of the red cell membrane remain the type of the patient, rather than the donor.  This is true of the Lewis phenotype (for instance, if the recipient was Le[a+b-], and the donor was Le[a-b+], after the transplant, the red cells will group as Le[a+b-], and not as Le[a-b+]}.  This is also true of antigens within the Chido/Rodgers Blood Group System, and certain others.

If the recipient is a Secretor, they will continue to secrete ABO substance of the original ABO type, which, of course, will also be adsorbed onto the red cell surface (as well as being in the plasma, leading to the phenomenon of "accommodation", and this is why most recipients stay with a reverse group of "AB" after an ABO mis-matched stem cell/bone marrow transplant.

SORRY TO BE A PEDANT, PARTICULARLY AS I AGREE WITH EVERYTHING ELSE YOU HAVE WRITTEN!

Sorry Neil, but I have to point out that this is not completely accurate.  Any red cell antigens that are adsorbed onto the red cell surface, rather than being an integral part of the red cell membrane remain the type of the patient, rather than the donor.  This is true of the Lewis phenotype (for instance, if the recipient was Le[a+b-], and the donor was Le[a-b+], after the transplant, the red cells will group as Le[a+b-], and not as Le[a-b+]}.  This is also true of antigens within the Chido/Rodgers Blood Group System, and certain others.

If the recipient is a Secretor, they will continue to secrete ABO substance of the original ABO type, which, of course, will also be adsorbed onto the red cell surface (as well as being in the plasma, leading to the phenomenon of "accommodation", and this is why most recipients stay with a reverse group of "AB" after an ABO mis-matched stem cell/bone marrow transplant.

SORRY TO BE A PEDANT, PARTICULARLY AS I AGREE WITH EVERYTHING ELSE YOU HAVE WRITTEN!

Sorry Neil, but I have to point out that this is not completely accurate.  Any red cell antigens that are adsorbed onto the red cell surface, rather than being an integral part of the red cell membrane remain the type of the patient, rather than the donor.  This is true of the Lewis phenotype (for instance, if the recipient was Le[a+b-], and the donor was Le[a-b+], after the transplant, the red cells will group as Le[a+b-], and not as Le[a-b+]}.  This is also true of antigens within the Chido/Rodgers Blood Group System, and certain others.

If the recipient is a Secretor, they will continue to secrete ABO substance of the original ABO type, which, of course, will also be adsorbed onto the red cell surface (as well as being in the plasma, leading to the phenomenon of "accommodation", and this is why most recipients stay with a reverse group of "AB" after an ABO mis-matched stem cell/bone marrow transplant.

SORRY TO BE A PEDANT, PARTICULARLY AS I AGREE WITH EVERYTHING ELSE YOU HAVE WRITTEN!

In the UK, the Guidelines would (quite correctly in my own opinion) NOT allow us to perform electronic issue on any sample, whatever the pathology, on a patient where the forward ABO type does not match the reverse ABO type (apart from Newborn babies).

Sorry Neil, but I have to point out that this is not completely accurate.  Any red cell antigens that are adsorbed onto the red cell surface, rather than being an integral part of the red cell membrane remain the type of the patient, rather than the donor.  This is true of the Lewis phenotype (for instance, if the recipient was Le[a+b-], and the donor was Le[a-b+], after the transplant, the red cells will group as Le[a+b-], and not as Le[a-b+]}.  This is also true of antigens within the Chido/Rodgers Blood Group System, and certain others.

If the recipient is a Secretor, they will continue to secrete ABO substance of the original ABO type, which, of course, will also be adsorbed onto the red cell surface (as well as being in the plasma, leading to the phenomenon of "accommodation", and this is why most recipients stay with a reverse group of "AB" after an ABO mis-matched stem cell/bone marrow transplant.

SORRY TO BE A PEDANT, PARTICULARLY AS I AGREE WITH EVERYTHING ELSE YOU HAVE WRITTEN!

Off the top of my head, as it were, the nearest source I can site is Hult AK, Dykes JH, Storry JR, Olsson ML.  A and B antigen levels acquired by group O donor-derived erythrocytes following ABO-non-identical transfusion or minor ABO-incompatible haematopoietic stem cell transplantation.  Transfusion Medicine 2017; 27: 181-191.  DOI: 10.1111/tme.12411.

In the UK, the Guidelines would (quite correctly in my own opinion) NOT allow us to perform electronic issue on any sample, whatever the pathology, on a patient where the forward ABO type does not match the reverse ABO type (apart from Newborn babies).

Off the top of my head, as it were, the nearest source I can site is Hult AK, Dykes JH, Storry JR, Olsson ML.  A and B antigen levels acquired by group O donor-derived erythrocytes following ABO-non-identical transfusion or minor ABO-incompatible haematopoietic stem cell transplantation.  Transfusion Medicine 2017; 27: 181-191.  DOI: 10.1111/tme.12411.

When you have incompatible antigen or antibody, low level hemolysis occurs, probably with complement activation. This is not at levels clinically evident, but inflammation occurs. Inflammation potentiates (increases) B cell activation and provides one mechanism by which ABO non-identical red cell transfusion (without washing) increases rbc alloimmunization to other antigens being presented. It is known to the case, both from clinical observations (referenced in my previous post) and from animal models which provide evidence that the presence of inflammation increases alloimmunization to red cells and other antigens.  It's the mechanism by which adjuvants in vaccines increase immunization to microbial antigens in vaccines, by the way.  Inflammation.  Not a good thing if you are not infected and receiving transfused antigen :).  But useful if you are trying to get a beneficial immune response to an antigen.

Thank you very much Neil.

I just answered this question.

My Score PASS  

I just answered this question.

My Score PASS  

I just answered this question.

My Score PASS  

I just answered this question.

My Score PASS  

Perhaps this is one rare physician who actually reads the medical literature on the subject or has thought things through.
The history of this is very simple.  Based upon the experience of severe or fatal hemolytic transfusion reactions to whole blood, it was discovered that when a patient's ABO type was unknown, and urgent transfusion was life saving, group O was the least likely to result in disaster.  When group O red cells became available during the middle of the last century, with modest amounts of plasma left, it was decided by the then experts that this could be used for non-urgent, routine transfusions of all patients. So-called universal donor O red cells.  The problem, with the 100% accuracy of hindsight, was that we had no evidence this is was good, much less optimal practice. But it was convenient. It meant blood banks didn't have to stock all 8 Rh and ABO types, so it was good for us in the transfusion service. It wasn't good for patients.
Why is that?  Well, there is residual incompatible plasma with anti-A and anti-B in all group O red cells that haven't been washed or thoroughly volume depleted. Well, you might ask, and all of us have assumed for decades, that a few dozen milliliters of incompatible plasma is not a big deal.   The answer, now known to some extent, is that it is a big deal for some patients who are groups A, AB and probably B.  This small residual plasma can on rare occasions cause severe hemolysis.  It's 100% severe if it happens to you as a patient.  This has been known for decades. What is new is the data that recipients of ABO mismatched red cells (Group O in general) have a higher rate of red cell alloimmunization to other red cell antigens, (Transfusion 2012 Mar;52(3):635-40. doi: 10.1111/j.1537-2995.2011.03329.x; 2025 Mar;65(3):588-603. doi: 10.1111/trf.18135. higher rates of febrile and allergic reactions, (Transfusion 2012 Mar;52(3):635-40.doi: 10.1111/j.1537-2995.2011.03329.x.) higher rates of HLA alloimmunization, and perhaps overall higher rates of mortality (Transfusion. 2016 Mar;56(3):550-7.doi: 10.1111/trf.13376).
So, if you are a recipient, you want ABO identical transfusions, or compatible red cells that have had all or almost all of the plasma removed, as by washing, for example.
 
 
 

Neil Blumberg, I'll leave this one to you!

Neil Blumberg, I'll leave this one to you!

The +s stands for strongly expressed.

The expression of the P1 antigen varies considerably from person to person, but the reaction strength with anti-P1 is an inherited trait (i.e. the strength of the expression on the red cell surface).

"I apologize for this dumb question."  BBnoob69, NO QUESTION IS A DUMB QUESTION, IF YOU DO NOT KNOW THE ANSWER.  If you don't know the answer, the dumb thing is to not ask the question in the first place.  NEVER be afraid to ask a question on here,

Neil Blumberg, I'll leave this one to you!

I just LOVE the word "torment" Phil.
 
A teacher after my own heart!!!!!!!!!!!!!!!!!!!!

The +s stands for strongly expressed.

The expression of the P1 antigen varies considerably from person to person, but the reaction strength with anti-P1 is an inherited trait (i.e. the strength of the expression on the red cell surface).

"I apologize for this dumb question."  BBnoob69, NO QUESTION IS A DUMB QUESTION, IF YOU DO NOT KNOW THE ANSWER.  If you don't know the answer, the dumb thing is to not ask the question in the first place.  NEVER be afraid to ask a question on here,

The +s stands for strongly expressed.

The expression of the P1 antigen varies considerably from person to person, but the reaction strength with anti-P1 is an inherited trait (i.e. the strength of the expression on the red cell surface).

"I apologize for this dumb question."  BBnoob69, NO QUESTION IS A DUMB QUESTION, IF YOU DO NOT KNOW THE ANSWER.  If you don't know the answer, the dumb thing is to not ask the question in the first place.  NEVER be afraid to ask a question on here,

The +s stands for strongly expressed.

The expression of the P1 antigen varies considerably from person to person, but the reaction strength with anti-P1 is an inherited trait (i.e. the strength of the expression on the red cell surface).

"I apologize for this dumb question."  BBnoob69, NO QUESTION IS A DUMB QUESTION, IF YOU DO NOT KNOW THE ANSWER.  If you don't know the answer, the dumb thing is to not ask the question in the first place.  NEVER be afraid to ask a question on here,