Posted November 20, 20195 yr comment_78968 In UK Discussing Red cell specification to issue to D neg females under child bearing age K Neg is standard requirement but what are the recommendations for also selecting rr units to avoid anti C or anti E sensitation in rr recipients. Would you just give rr to all D neg whether rr or not
November 20, 20195 yr comment_78969 Given that EVERY unit of blood within the UK is tested for the Rh phenotype, as near as can be done, ignoring some of the more obscure mutations, it should be pretty easy to give Rh-matched (not necessarily Rh-identical) and K Negative matched (unless of course, the patient is K positive themselves - about 8% are, give or take), it should not be difficult, except in cases of, possibly R2R2 or other, even more rare phenotypes, and in cases where massive, urgent transfusion is required, to give Rh and K-matched blood to ALL females of child-bearing potential, from the age of 0 to the age of 50 (the upper age being defined by BSH after many studies - see studies undertaken by Dr Edwin Massie). If this is followed, there should be no problems about either anti-C or anti-E being stimulated by transfusion, as opposed to pregnancy. That having been said, anti-C is not very immunogenic in the first place, while anti-E (or anti-E-like antibodies) are not uncommon as "naturally occurring" antibodies.
August 19, 20204 yr comment_80833 Hi Pluto, In my hospital historically we always provided O neg, K-, rr units in adult emergency situations (as flying squad, Massive Haemorrhage Protocol activations on unknown patients etc...), but recently changed this practice to only provide O neg, K-. More often than not the units are rr anyway by the nature of rr being the most common phenotype in D neg UK donors. We searched for literature for and against prior to the change and didn't come up with much. It would be lovely to provide suitably Rh/K matched units for women <50 to protect against immunisation against anti-c in particular, due to the implications in HDN, but this is often not practically possible in the above mentioned emergency situations. And once a patient has received the emergency O neg blood, a Rh/K phenotype is void due to recent transfusion. We have also discussed around Rh/K typing all females <50 and thereby providing Rh/K matched blood (again to prevent anti-c development where applicable), but there are many situations where we would possibly end up with deviations against procedures to provide suitable blood which wouldn't be Rh/K matched, and covering a wide demographic of patients across two large hospital campuses logistically it would start to get very complicated to have these rules in place with suitably testing of >100 samples a day, recording in LIMS with appropriate special requirements updated and suitable phenotypes stored separately in the stock fridge for all different patients and situations. Maybe a bit too much of a headache to prevent the "what ifs" in every situation?
August 20, 20204 yr comment_80835 17 hours ago, NicolaHT said: Hi Pluto, In my hospital historically we always provided O neg, K-, rr units in adult emergency situations (as flying squad, Massive Haemorrhage Protocol activations on unknown patients etc...), but recently changed this practice to only provide O neg, K-. More often than not the units are rr anyway by the nature of rr being the most common phenotype in D neg UK donors. We searched for literature for and against prior to the change and didn't come up with much. It would be lovely to provide suitably Rh/K matched units for women <50 to protect against immunisation against anti-c in particular, due to the implications in HDN, but this is often not practically possible in the above mentioned emergency situations. And once a patient has received the emergency O neg blood, a Rh/K phenotype is void due to recent transfusion. We have also discussed around Rh/K typing all females <50 and thereby providing Rh/K matched blood (again to prevent anti-c development where applicable), but there are many situations where we would possibly end up with deviations against procedures to provide suitable blood which wouldn't be Rh/K matched, and covering a wide demographic of patients across two large hospital campuses logistically it would start to get very complicated to have these rules in place with suitably testing of >100 samples a day, recording in LIMS with appropriate special requirements updated and suitable phenotypes stored separately in the stock fridge for all different patients and situations. Maybe a bit too much of a headache to prevent the "what ifs" in every situation? The only patients you will come across who are both D Negative and c Negative, who do not have some form of gene deletion, are going to be r'r', ryry or r'ry. All three of these phenotypes come under the heading of exceptionally rare. To have r'r', ryry or r'ry blood available in a hospital blood bank (even a Regional Transfusion Centre close by) at the same time as you have an exceptionally rare patient in your A&E Department (or wherever) would have odds greater than winning both the National Lottery AND the Euromillions lottery at the same time! Anti-c is nasty in pregnancy (true), but, these days, foetal medicine is advanced enough to make it fairly easy with which to deal.
August 20, 20204 yr comment_80840 I hear there is some chatter/literature about immunizing Rh-Neg Females under 50 is, today, probably 'much ado about nothing'. Well, not nothing, but the argument is, with today's techniques (in utero transfusions, more sensitive monitoring, etc.), the risk of HDN is less likely than it was 'all those years ago'. Does anyone have any articles or insight about this 'new turn' to share?
August 21, 20204 yr comment_80846 On 8/20/2020 at 2:22 PM, Joanne P. Scannell said: I hear there is some chatter/literature about immunizing Rh-Neg Females under 50 is, today, probably 'much ado about nothing'. Well, not nothing, but the argument is, with today's techniques (in utero transfusions, more sensitive monitoring, etc.), the risk of HDN is less likely than it was 'all those years ago'. Does anyone have any articles or insight about this 'new turn' to share? NONE!
August 22, 20204 yr comment_80859 On 8/20/2020 at 7:22 AM, Joanne P. Scannell said: I hear there is some chatter/literature about immunizing Rh-Neg Females under 50 is, today, probably 'much ado about nothing'. Well, not nothing, but the argument is, with today's techniques (in utero transfusions, more sensitive monitoring, etc.), the risk of HDN is less likely than it was 'all those years ago'. Does anyone have any articles or insight about this 'new turn' to share? So, just where are you hearing this?
August 22, 20204 yr comment_80869 On 11/21/2019 at 1:10 AM, Malcolm Needs said: Given that EVERY unit of blood within the UK is tested for the Rh phenotype, as near as can be done, ignoring some of the more obscure mutations, it should be pretty easy to give Rh-matched (not necessarily Rh-identical) and K Negative matched (unless of course, the patient is K positive themselves - about 8% are, give or take), it should not be difficult, except in cases of, possibly R2R2 or other, even more rare phenotypes, and in cases where massive, urgent transfusion is required, to give Rh and K-matched blood to ALL females of child-bearing potential, from the age of 0 to the age of 50 (the upper age being defined by BSH after many studies - see studies undertaken by Dr Edwin Massie). If this is followed, there should be no problems about either anti-C or anti-E being stimulated by transfusion, as opposed to pregnancy. That having been said, anti-C is not very immunogenic in the first place, while anti-E (or anti-E-like antibodies) are not uncommon as "naturally occurring" antibodies. Hi Malcolm, you mention that in massive, urgent transfusions to give Rh and K-matched blood for females of child-bearing potential from the age of 0. What about routine top-up transfusions for female neonates from age 0? Should they get Rh matched blood? Or only from four months old onwards?
August 22, 20204 yr comment_80870 22 minutes ago, YorkshireExile said: Hi Malcolm, you mention that in massive, urgent transfusions to give Rh and K-matched blood for females of child-bearing potential from the age of 0. What about routine top-up transfusions for female neonates from age 0? Should they get Rh matched blood? Or only from four months old onwards? Personally, I would give Rh and K-matched to all females from the age of 0 until the official age when they are "no longer of child-bearing potential" (this differs from country to country and, indeed, from individual to individual, but most countries "state an age"), unless there are extenuating circumstances, such as either an incredibly rare Rh phenotype or an incredibly rare Kell type, when "matched blood" may not be available, or may not be available in the time required. There is a theory that if "unmatched blood" (Rh and K of course, NOT ABO!) in the first few days/weeks/months of life, then there can be lifetime tolerance of certain antigens (as there is with chimeras - a sort of "accommodation"), but I wouldn't like to be the one performing the experiments!!!!!!!
August 25, 20204 yr comment_80885 On 8/20/2020 at 12:29 PM, Malcolm Needs said: The only patients you will come across who are both D Negative and c Negative, who do not have some form of gene deletion, are going to be r'r', ryry or r'ry. All three of these phenotypes come under the heading of exceptionally rare. To have r'r', ryry or r'ry blood available in a hospital blood bank (even a Regional Transfusion Centre close by) at the same time as you have an exceptionally rare patient in your A&E Department (or wherever) would have odds greater than winning both the National Lottery AND the Euromillions lottery at the same time! Anti-c is nasty in pregnancy (true), but, these days, foetal medicine is advanced enough to make it fairly easy with which to deal. Sorry Malcolm, I was referring to women who are D pos R1R1, given rr in an emergency and then develop anti-c! We wouldn't have time to Rh/K type or match these patients before the provision of emergency units, which are selected to be O Negative, K negative to protect against anti-D and anti-K, but we're a bit limited in protecting against anti-c.
August 25, 20204 yr comment_80890 1 hour ago, NicolaHT said: Sorry Malcolm, I was referring to women who are D pos R1R1, given rr in an emergency and then develop anti-c! We wouldn't have time to Rh/K type or match these patients before the provision of emergency units, which are selected to be O Negative, K negative to protect against anti-D and anti-K, but we're a bit limited in protecting against anti-c. Ah right. Sorry.
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