Malcolm Needs

The reason that Jk(a) variants tend to weaken the antigen expression is because of the way the amino acid residue that produces the antigen is very close to the red cell membrane and is"semi-hidden" by the third external loop (see the attached diagram).Kidd Molecule.ppt

I agree 100% with Anna.
We actually see a few of these every year.
The only thing that I would say is that variant Jk(a) antigens are few and far between, and usually result in considerable weakening of the Jk(a) antigen. In this case, your results point to a normal expression of the antigen.

The reason that Jk(a) variants tend to weaken the antigen expression is because of the way the amino acid residue that produces the antigen is very close to the red cell membrane and is"semi-hidden" by the third external loop (see the attached diagram).Kidd Molecule.ppt

The reason that Jk(a) variants tend to weaken the antigen expression is because of the way the amino acid residue that produces the antigen is very close to the red cell membrane and is"semi-hidden" by the third external loop (see the attached diagram).Kidd Molecule.ppt

I have ABSOLUTELY no doubt that the antibody is anti-f.
Just because the patient is e+ in no way precludes him from making anti-f, the "other name" for which is anti-ce. In other words, it is a COMPOUND antibody that will only react when the RHc and RHe genes are in the cis position (but not in the trans position, and not when only one of the antigens (in this case, the e antigen) is expressed on the red cells of the antibody producer.

It was pretty obvious but - I've been in the field over 40 yrs and this is the first anti-f for me.  It just made me uncomfortable but when I wrote out CDe/CDe instead of R1R1 I thought for sure that it could be anti-f.  Just needed some reassurance.

Aren't those compound antigens fun?  We just referred a pregnant patient for antibody ID and titer with a history of anti-C, but we were getting additional reactions that we couldn't quite figure out.  Our reference lab had to refer it to a Level 1 reference lab because they couldn't figure it out either.  Turned out to actually be an anti-rhi AND an anti-e (overkill??).  Anti-C was excluded.  I looked back at our original panel on this patient and the reactivity did appeared to be an anti-C, even in hindsight.

I have ABSOLUTELY no doubt that the antibody is anti-f.
Just because the patient is e+ in no way precludes him from making anti-f, the "other name" for which is anti-ce. In other words, it is a COMPOUND antibody that will only react when the RHc and RHe genes are in the cis position (but not in the trans position, and not when only one of the antigens (in this case, the e antigen) is expressed on the red cells of the antibody producer.

Thanks Malcolm - I was leaning there.  In fact I just called the hospital and told I was pretty certain it was anti-f.

Thank you so much Malcolm!  That explanation was so very helpful! And the slide you attached was great!! Thanks again for your help!

Testing for antiG.ppt
With a bit of luck, this may explain a bit easier what I was trying to explain in words.

Hi Sara,
The first clue that the antibody may be anti-G, or anti-C+G, rather than anti-C+D, is indeed that the titre of the anti-C is higher than that of the anti-D, but the fact that the anti-C titre is higher than that of the anti-D is only a clue. It could be that you actually have an anti-C+D where, coincidentally, the anti-C titre is higher than the anti-D. It is absolutely essential, therefore, that you can prove that no anti-D is present.
One way of doing this is to divide the patient's plasma sample into two.
The first sample is adsorbed using Ro red cells treated with a proteolytic enzyme, such as papain or ficin, which would adsorb out any anti-G and any anti-D present, but would leave any anti-C present. At the end of the adsorption process (about 4 cycles), this plasma is tested against r'r red cells by IAT. If there is a positive reaction, then the original plasma contained anti-C and, possibly, anti-G. If there is a negative reaction, then the original plasma contained, possibly, anti-G and anti-D, but not anti-C.
The second sample is adsorbed using r'r red cells treated with a proteolytic enzyme, such as papain or ficin, which would adsorb out any anti-G and any anti-C present, but would leave any anti-D present. At the end of the adsorption process (about 4 cycles), this plasma is tested against Ro red cells by IAT. If there is a positive reaction, then the original plasma contained anti-D and, possibly, anti-G. If there is a negative reaction, then the original plasma contained, possibly, anti-G and anti-C, but not anti-D.
So, if there are no reactions with the plasma adsorbed with Ro red cells when tested with r'r red cells, and no reactions with the plasma adsorbed with r'r red cells when tested with Ro red cells, then the original plasma contained only anti-G.
If there is a reaction with the plasma adsorbed with Ro red cells when tested with r'r red cells, and also a reaction with the plasma adsorbed with r'r red cells when tested with Ro red cells, then the original plasma contained both anti-C and anti-D (and may also have contained an anti-G).
In all cases, however, you would give cross-match compatible C Negative, D Negative blood (you would still have to perform a serological cross-match, because there are some EXTREMELY rare donors around who are C Negative, D negative, but G POSITIVE.
As far as obstetric patients are concerned, both anti-C and anti-G usually cause far less severe haemolytic disease of the foetus and newborn (unless they have an unusually high titre), than does anti-D. However, it is important that the pregnant lady is offered prenatal and postnatal anti-D immunoglobulin prophylaxis, so that they do not get immunised against the D antigen.
I hope that this rather long and complicated post helps in some way, but, if you need to know more, please do not hesitate to ask more questions.

I entirely agree with David.
Even if you should detect an antibody that was known to be present in a previous pregnancy, the history may be important.
For example, we have recently dealt with a first sample in pregnancy in a third pregnancy from a lady with anti-D. The referring hospital was different from that in the previous pregnancy. The first sample this time gave an anti-D level of 3.8IU/mL (in other words, unlikely to cause clinically significant HDNF). However, towards the end of the previous pregnancy, the anti-D had risen to a level of 25IU/mL (very likely to cause clinically significant HDNF). We were able, therefore, to include this fact in the report on the present sample, which would act as a "heads up" for the Obstetrician looking after the new pregnancy that very close monitoring would be in order.

Hi Sara,
The first clue that the antibody may be anti-G, or anti-C+G, rather than anti-C+D, is indeed that the titre of the anti-C is higher than that of the anti-D, but the fact that the anti-C titre is higher than that of the anti-D is only a clue. It could be that you actually have an anti-C+D where, coincidentally, the anti-C titre is higher than the anti-D. It is absolutely essential, therefore, that you can prove that no anti-D is present.
One way of doing this is to divide the patient's plasma sample into two.
The first sample is adsorbed using Ro red cells treated with a proteolytic enzyme, such as papain or ficin, which would adsorb out any anti-G and any anti-D present, but would leave any anti-C present. At the end of the adsorption process (about 4 cycles), this plasma is tested against r'r red cells by IAT. If there is a positive reaction, then the original plasma contained anti-C and, possibly, anti-G. If there is a negative reaction, then the original plasma contained, possibly, anti-G and anti-D, but not anti-C.
The second sample is adsorbed using r'r red cells treated with a proteolytic enzyme, such as papain or ficin, which would adsorb out any anti-G and any anti-C present, but would leave any anti-D present. At the end of the adsorption process (about 4 cycles), this plasma is tested against Ro red cells by IAT. If there is a positive reaction, then the original plasma contained anti-D and, possibly, anti-G. If there is a negative reaction, then the original plasma contained, possibly, anti-G and anti-C, but not anti-D.
So, if there are no reactions with the plasma adsorbed with Ro red cells when tested with r'r red cells, and no reactions with the plasma adsorbed with r'r red cells when tested with Ro red cells, then the original plasma contained only anti-G.
If there is a reaction with the plasma adsorbed with Ro red cells when tested with r'r red cells, and also a reaction with the plasma adsorbed with r'r red cells when tested with Ro red cells, then the original plasma contained both anti-C and anti-D (and may also have contained an anti-G).
In all cases, however, you would give cross-match compatible C Negative, D Negative blood (you would still have to perform a serological cross-match, because there are some EXTREMELY rare donors around who are C Negative, D negative, but G POSITIVE.
As far as obstetric patients are concerned, both anti-C and anti-G usually cause far less severe haemolytic disease of the foetus and newborn (unless they have an unusually high titre), than does anti-D. However, it is important that the pregnant lady is offered prenatal and postnatal anti-D immunoglobulin prophylaxis, so that they do not get immunised against the D antigen.
I hope that this rather long and complicated post helps in some way, but, if you need to know more, please do not hesitate to ask more questions.

It can be difficult to identify those infants who fall into the categories AABB lists as those that require irradiated products. One of the immune deficiencies encountered in infants is DeGeorge syndrome (an immunodeficiency that often occurs with cardiac anomalies). That diagnosis is not identified immediately upon admission to a NICU or CVICU. My institution has a 98 bed NICU and a 28 bed pediatric CVICU. For patient safety, we irradiate all products for infants in NICU or CVICU regardless of their birthweight. Yes, we do have our own irradiator. We also limit donor exposure by designating a specific unit for a baby and use until its expiration for small volume transfusions. If a large volume transfusion is needed (for OR) a fresh, irradiated unit is selected. And we do give fresh, < 5 day old blood to all cardiac surgery patients < 2 years of age.

Its funny that the author mentions the fact that the blood supply system is a billion dollar industry in the US, -- he does not point out that almost all of it is not-for-profit.  (i wonder if the author and the expert lecturer he refers to are not for profit?)
 
This is the internet - a blog no less.  ALL of the information there is going to be inflammatory and filled with half-truths and distortions.  That's what the internet is for, isn't it? 
 
Bloggers exist because we like to read about adversity.  Who wants to read about how safe the blood supply is?  Asking for some kind of response for a counter-argument form "the other side" would only validate the authority of the blogger.  Its undignified.  Try to forget about it.
 
If a patient asks about any "controversy" generated by this article, ask him who they trust with thier health - thier own doctor or some blogger?
 
Scott

Hi Sara,
The first clue that the antibody may be anti-G, or anti-C+G, rather than anti-C+D, is indeed that the titre of the anti-C is higher than that of the anti-D, but the fact that the anti-C titre is higher than that of the anti-D is only a clue. It could be that you actually have an anti-C+D where, coincidentally, the anti-C titre is higher than the anti-D. It is absolutely essential, therefore, that you can prove that no anti-D is present.
One way of doing this is to divide the patient's plasma sample into two.
The first sample is adsorbed using Ro red cells treated with a proteolytic enzyme, such as papain or ficin, which would adsorb out any anti-G and any anti-D present, but would leave any anti-C present. At the end of the adsorption process (about 4 cycles), this plasma is tested against r'r red cells by IAT. If there is a positive reaction, then the original plasma contained anti-C and, possibly, anti-G. If there is a negative reaction, then the original plasma contained, possibly, anti-G and anti-D, but not anti-C.
The second sample is adsorbed using r'r red cells treated with a proteolytic enzyme, such as papain or ficin, which would adsorb out any anti-G and any anti-C present, but would leave any anti-D present. At the end of the adsorption process (about 4 cycles), this plasma is tested against Ro red cells by IAT. If there is a positive reaction, then the original plasma contained anti-D and, possibly, anti-G. If there is a negative reaction, then the original plasma contained, possibly, anti-G and anti-C, but not anti-D.
So, if there are no reactions with the plasma adsorbed with Ro red cells when tested with r'r red cells, and no reactions with the plasma adsorbed with r'r red cells when tested with Ro red cells, then the original plasma contained only anti-G.
If there is a reaction with the plasma adsorbed with Ro red cells when tested with r'r red cells, and also a reaction with the plasma adsorbed with r'r red cells when tested with Ro red cells, then the original plasma contained both anti-C and anti-D (and may also have contained an anti-G).
In all cases, however, you would give cross-match compatible C Negative, D Negative blood (you would still have to perform a serological cross-match, because there are some EXTREMELY rare donors around who are C Negative, D negative, but G POSITIVE.
As far as obstetric patients are concerned, both anti-C and anti-G usually cause far less severe haemolytic disease of the foetus and newborn (unless they have an unusually high titre), than does anti-D. However, it is important that the pregnant lady is offered prenatal and postnatal anti-D immunoglobulin prophylaxis, so that they do not get immunised against the D antigen.
I hope that this rather long and complicated post helps in some way, but, if you need to know more, please do not hesitate to ask more questions.

Testing for antiG.ppt
With a bit of luck, this may explain a bit easier what I was trying to explain in words.

Hi Sara,
The first clue that the antibody may be anti-G, or anti-C+G, rather than anti-C+D, is indeed that the titre of the anti-C is higher than that of the anti-D, but the fact that the anti-C titre is higher than that of the anti-D is only a clue. It could be that you actually have an anti-C+D where, coincidentally, the anti-C titre is higher than the anti-D. It is absolutely essential, therefore, that you can prove that no anti-D is present.
One way of doing this is to divide the patient's plasma sample into two.
The first sample is adsorbed using Ro red cells treated with a proteolytic enzyme, such as papain or ficin, which would adsorb out any anti-G and any anti-D present, but would leave any anti-C present. At the end of the adsorption process (about 4 cycles), this plasma is tested against r'r red cells by IAT. If there is a positive reaction, then the original plasma contained anti-C and, possibly, anti-G. If there is a negative reaction, then the original plasma contained, possibly, anti-G and anti-D, but not anti-C.
The second sample is adsorbed using r'r red cells treated with a proteolytic enzyme, such as papain or ficin, which would adsorb out any anti-G and any anti-C present, but would leave any anti-D present. At the end of the adsorption process (about 4 cycles), this plasma is tested against Ro red cells by IAT. If there is a positive reaction, then the original plasma contained anti-D and, possibly, anti-G. If there is a negative reaction, then the original plasma contained, possibly, anti-G and anti-C, but not anti-D.
So, if there are no reactions with the plasma adsorbed with Ro red cells when tested with r'r red cells, and no reactions with the plasma adsorbed with r'r red cells when tested with Ro red cells, then the original plasma contained only anti-G.
If there is a reaction with the plasma adsorbed with Ro red cells when tested with r'r red cells, and also a reaction with the plasma adsorbed with r'r red cells when tested with Ro red cells, then the original plasma contained both anti-C and anti-D (and may also have contained an anti-G).
In all cases, however, you would give cross-match compatible C Negative, D Negative blood (you would still have to perform a serological cross-match, because there are some EXTREMELY rare donors around who are C Negative, D negative, but G POSITIVE.
As far as obstetric patients are concerned, both anti-C and anti-G usually cause far less severe haemolytic disease of the foetus and newborn (unless they have an unusually high titre), than does anti-D. However, it is important that the pregnant lady is offered prenatal and postnatal anti-D immunoglobulin prophylaxis, so that they do not get immunised against the D antigen.
I hope that this rather long and complicated post helps in some way, but, if you need to know more, please do not hesitate to ask more questions.

Hi NAN47,
Any antibody that reacts at STRICTLY 37oC should be titrated during pregnancy (except, of course, for anti-D and anti-c, which, in the UK, are measured by quantification against NIBSC standards).
The titration should take place at first identification and then again at 28 weeks gestation. If the titre is less than 32, then the antibody is unlikely to cause clinically significant alloimmune haemolytic anaemia and disease of the foetus and newborn. Only rarely is an antibody titre high enough to warrant further titration after 28 weeks gestation.
The obvious exception to this is anti-K (and other Kell-related antibodies). These should be titrated when first identified, and then every four weeks to 28 weeks gestation, and then 2 weekly thereafter, until delivery. Indeed, women with anti-K who are pregnant, and who have a partner who is K+k+ or K+k- should be referred to a Specialist Foetal Medicine Unit, so that the pregnancy can be monitored by experts in the field.
It is always recommended that the previous sample is titrated in parallel with the present sample (or quantified, in the case of anti-D or anti-c), as this will show up genuine rises in the titre, as opposed to rises due to operator differences and errors and changes due to the different expression strengths of an antigen from one red cell sample to another. Where possible, the red cells used should have heterozygous expression of the antigen, although, in certain cases, this can be difficult to do (e.g., if the antibody is anti-U, it is not possible to tell whether the red cells used for the titration are U+/U+ or U+/U-).
In rare cases, titration of the previous sample, in parallel with the present sample, may show up a second specificity. For example, if the pregnant woman is known to have an anti-E, with a titre of, for example, 4 against r"r red cells, and then all of a sudden the titre goes up to 128, but ALSO shows as 128 with the previous sample run in parallel, it may be that the r"r red cells used on this occasion also express an antigen against a low prevalence antigen, against which the woman has also produced an antibody (for example, an anti-Wra).
The end point of a titration is usually given as the reciprocal of the last dilution in which agglutination can be seen with the naked eye.
We are actively re-writing the BCSH Guidelines (technical guidelines) as I post, and the complementary RCOG Guidelines (clinical guidelines) are also in their final draft.

I am a student of Malcolm,but I can help; just double click the small graph and it will turn big enough to be useful.

Hi Sara,
The first clue that the antibody may be anti-G, or anti-C+G, rather than anti-C+D, is indeed that the titre of the anti-C is higher than that of the anti-D, but the fact that the anti-C titre is higher than that of the anti-D is only a clue. It could be that you actually have an anti-C+D where, coincidentally, the anti-C titre is higher than the anti-D. It is absolutely essential, therefore, that you can prove that no anti-D is present.
One way of doing this is to divide the patient's plasma sample into two.
The first sample is adsorbed using Ro red cells treated with a proteolytic enzyme, such as papain or ficin, which would adsorb out any anti-G and any anti-D present, but would leave any anti-C present. At the end of the adsorption process (about 4 cycles), this plasma is tested against r'r red cells by IAT. If there is a positive reaction, then the original plasma contained anti-C and, possibly, anti-G. If there is a negative reaction, then the original plasma contained, possibly, anti-G and anti-D, but not anti-C.
The second sample is adsorbed using r'r red cells treated with a proteolytic enzyme, such as papain or ficin, which would adsorb out any anti-G and any anti-C present, but would leave any anti-D present. At the end of the adsorption process (about 4 cycles), this plasma is tested against Ro red cells by IAT. If there is a positive reaction, then the original plasma contained anti-D and, possibly, anti-G. If there is a negative reaction, then the original plasma contained, possibly, anti-G and anti-C, but not anti-D.
So, if there are no reactions with the plasma adsorbed with Ro red cells when tested with r'r red cells, and no reactions with the plasma adsorbed with r'r red cells when tested with Ro red cells, then the original plasma contained only anti-G.
If there is a reaction with the plasma adsorbed with Ro red cells when tested with r'r red cells, and also a reaction with the plasma adsorbed with r'r red cells when tested with Ro red cells, then the original plasma contained both anti-C and anti-D (and may also have contained an anti-G).
In all cases, however, you would give cross-match compatible C Negative, D Negative blood (you would still have to perform a serological cross-match, because there are some EXTREMELY rare donors around who are C Negative, D negative, but G POSITIVE.
As far as obstetric patients are concerned, both anti-C and anti-G usually cause far less severe haemolytic disease of the foetus and newborn (unless they have an unusually high titre), than does anti-D. However, it is important that the pregnant lady is offered prenatal and postnatal anti-D immunoglobulin prophylaxis, so that they do not get immunised against the D antigen.
I hope that this rather long and complicated post helps in some way, but, if you need to know more, please do not hesitate to ask more questions.

Thanks Malcolm,for the great explanation as usual.

Hi Sara,
The first clue that the antibody may be anti-G, or anti-C+G, rather than anti-C+D, is indeed that the titre of the anti-C is higher than that of the anti-D, but the fact that the anti-C titre is higher than that of the anti-D is only a clue. It could be that you actually have an anti-C+D where, coincidentally, the anti-C titre is higher than the anti-D. It is absolutely essential, therefore, that you can prove that no anti-D is present.
One way of doing this is to divide the patient's plasma sample into two.
The first sample is adsorbed using Ro red cells treated with a proteolytic enzyme, such as papain or ficin, which would adsorb out any anti-G and any anti-D present, but would leave any anti-C present. At the end of the adsorption process (about 4 cycles), this plasma is tested against r'r red cells by IAT. If there is a positive reaction, then the original plasma contained anti-C and, possibly, anti-G. If there is a negative reaction, then the original plasma contained, possibly, anti-G and anti-D, but not anti-C.
The second sample is adsorbed using r'r red cells treated with a proteolytic enzyme, such as papain or ficin, which would adsorb out any anti-G and any anti-C present, but would leave any anti-D present. At the end of the adsorption process (about 4 cycles), this plasma is tested against Ro red cells by IAT. If there is a positive reaction, then the original plasma contained anti-D and, possibly, anti-G. If there is a negative reaction, then the original plasma contained, possibly, anti-G and anti-C, but not anti-D.
So, if there are no reactions with the plasma adsorbed with Ro red cells when tested with r'r red cells, and no reactions with the plasma adsorbed with r'r red cells when tested with Ro red cells, then the original plasma contained only anti-G.
If there is a reaction with the plasma adsorbed with Ro red cells when tested with r'r red cells, and also a reaction with the plasma adsorbed with r'r red cells when tested with Ro red cells, then the original plasma contained both anti-C and anti-D (and may also have contained an anti-G).
In all cases, however, you would give cross-match compatible C Negative, D Negative blood (you would still have to perform a serological cross-match, because there are some EXTREMELY rare donors around who are C Negative, D negative, but G POSITIVE.
As far as obstetric patients are concerned, both anti-C and anti-G usually cause far less severe haemolytic disease of the foetus and newborn (unless they have an unusually high titre), than does anti-D. However, it is important that the pregnant lady is offered prenatal and postnatal anti-D immunoglobulin prophylaxis, so that they do not get immunised against the D antigen.
I hope that this rather long and complicated post helps in some way, but, if you need to know more, please do not hesitate to ask more questions.

Hi Sara,
The first clue that the antibody may be anti-G, or anti-C+G, rather than anti-C+D, is indeed that the titre of the anti-C is higher than that of the anti-D, but the fact that the anti-C titre is higher than that of the anti-D is only a clue. It could be that you actually have an anti-C+D where, coincidentally, the anti-C titre is higher than the anti-D. It is absolutely essential, therefore, that you can prove that no anti-D is present.
One way of doing this is to divide the patient's plasma sample into two.
The first sample is adsorbed using Ro red cells treated with a proteolytic enzyme, such as papain or ficin, which would adsorb out any anti-G and any anti-D present, but would leave any anti-C present. At the end of the adsorption process (about 4 cycles), this plasma is tested against r'r red cells by IAT. If there is a positive reaction, then the original plasma contained anti-C and, possibly, anti-G. If there is a negative reaction, then the original plasma contained, possibly, anti-G and anti-D, but not anti-C.
The second sample is adsorbed using r'r red cells treated with a proteolytic enzyme, such as papain or ficin, which would adsorb out any anti-G and any anti-C present, but would leave any anti-D present. At the end of the adsorption process (about 4 cycles), this plasma is tested against Ro red cells by IAT. If there is a positive reaction, then the original plasma contained anti-D and, possibly, anti-G. If there is a negative reaction, then the original plasma contained, possibly, anti-G and anti-C, but not anti-D.
So, if there are no reactions with the plasma adsorbed with Ro red cells when tested with r'r red cells, and no reactions with the plasma adsorbed with r'r red cells when tested with Ro red cells, then the original plasma contained only anti-G.
If there is a reaction with the plasma adsorbed with Ro red cells when tested with r'r red cells, and also a reaction with the plasma adsorbed with r'r red cells when tested with Ro red cells, then the original plasma contained both anti-C and anti-D (and may also have contained an anti-G).
In all cases, however, you would give cross-match compatible C Negative, D Negative blood (you would still have to perform a serological cross-match, because there are some EXTREMELY rare donors around who are C Negative, D negative, but G POSITIVE.
As far as obstetric patients are concerned, both anti-C and anti-G usually cause far less severe haemolytic disease of the foetus and newborn (unless they have an unusually high titre), than does anti-D. However, it is important that the pregnant lady is offered prenatal and postnatal anti-D immunoglobulin prophylaxis, so that they do not get immunised against the D antigen.
I hope that this rather long and complicated post helps in some way, but, if you need to know more, please do not hesitate to ask more questions.