Jump to content
PathLabTalk

Malcolm Needs

Premium Members
  • Content Count

    7,756
  • Joined

  • Last visited

  • Days Won

    800
  • Country

    United Kingdom

Everything posted by Malcolm Needs

  1. Do you know, I wondered if it was you. Glad to see you back. We need people like you.
  2. There is no such thing as anti-Du. Therefore, there cannot be blood that is Du positive. Some individuals who have a normal RHD gene express a weaken D antigen because of the "Ceppellini effect" of having either a RHCE*Ce or a RHCE*CE gene in the trans position (see Ceppellini R, Dunn LC, Turri M. An interaction between alleles at the Rh locus in man which weakens the reactivity of the Rh0 factor (Du). Proc nat Acad Sci, Wash 1955; 41: 283-288), but such individuals are still not Du positive.
  3. Certainly the blood supplied by the NHSBT that what is on the label on the outside is GUARANTEED to be what is actually in the bag, and so no retyping is required. I THINK the same applies in Scotland, Wales and Northern Ireland, although am happy to be corrected. As all such "kills" would be reported to our regulatory authorities, and published in the annual Serious Hazards of Transfusion (SHOT) Report, I can say for certain that no "kills" have been reported for many, many years!
  4. There were time when we would use NISS, rather than LISS, when the auto-antibody was really strong. Remember, before LISS, NISS was what we used all the time, and not everyone who received blood in those days keeled over and died as a result!
  5. NicolePCanada, I agree entirely with Ward_X, but with the caveat that workers must remain competent in the method.
  6. Thanks for that. The antigens of the MNS Blood Group System (there are now 39 different systems, but well over 200 different antigens), of which there are actually 49 antigens within this single system, are largely receptors for complement, bacteria and viruses , such as Eschericia coli and influenza A and B virus, but the carrier molecule upon which S is expressed is also a ligand for the malarial parasite Plasmodium falcipaum.
  7. Anti-D is an antibody directed against the D antigen of the Rh Blood Group System. Anti-S is an antibody directed against the S antigen of the MNS Blood Group System. Anti-D has often caused severe haemolytic disease of the foetus and newborn. Anti-S, on the other hand, although it has caused severe haemolytic disease of the foetus and newborn, it only does so in VERY rare cases. These days, with the vast improvement in foetal medicine, neither antibody should cause real problems to either the mother or the baby. Antibodies to antigens other than ABO in the circulation are not
  8. Please see my reply to you earlier in the "Welcome Bot".
  9. Firstly, welcome fletob. There are several explanations for this, and the first one is that the blood drawn in 2011 was either from another student, or that the test was less than accurate (were the samples accurately labelled, and were strict positive and negative controls used). After that, if the antibody screen was negative at 13 weeks of gestation, but positive at 29 weeks of gestation, then either the anti-D has arisen due purely to passive injection, or an extremely unusual case of anti-D sensitisation in a first pregnancy, and an even more unusual case of a serious case of al
  10. When I first joined the wonderful world of blood transfusion, with particular reference to blood group serology, at the International Blood Group Reference Laboratory, when it was in London, my mentors were Dr Carolyn Giles and Joyce Poole. In those days, yes, we did use microscopes (albeit with very little magnification) and, given that we were using human-derived antisera, and the fact that I was anxious not to miss anything, I often got Joyce to check my sightings down the microscope. These were invariably "kissing cells", as you suggest, and Joyce christened them "Malcolm weaks", a term
  11. Clarest, does the N-HANCE package insert mention anywhere just WHY an optical aid is required? For example, does it explain why it is such an inferior reagent to all the others, including normal ionic strength saline and low ionic strength solution, that an optical aid is required?
  12. This is going back donkey's years, but when we used to adsorb raw AHG with human red cells to get rid of the xenoantibodies that reacted like anti-A and anti-B, we used the last supernatant to dilute an aliquot of a previous lot of AHG, and then saw if the AHG still worked. If it did, then the red cells were washed sufficiently free of human protein, which, otherwise, would have inhibited the AHG.
  13. Happy Birthday Cliff.

  14. True Joanne, it is very fast, but one of my points about this is that, when a baby is found to have a Weak or Partial D (such as Partial DVI), it would be good practice to test the mother for Weak or Partial D expression, if this has not already been done, because she may be the source of the mutant gene leading to the baby's Weak or Partial D type. If she is the source, then it is a moot point, to say the least, as to whether she should or should not be exposed to a human-derived blood product that may, for all we know, be harbouring novel virus that may be transfusion-transmitted. AT the v
  15. You have NEVER seen a baby who is Weak D Positive. There is no such thing as anti-Weak D! May I suggest that you read Stratton F. A new Rh allelomorph. Nature 1946; 158: 25-26, followed closely by Race RR, Sanger R, Lawler SD. The Rh antigen Du. Ann Eugen (Camb) 1948; 14: 171-184, which will explain why there is no such thing as anti-Weak D. I appreciate that CAP seem to be incapable of using correct terminology, but that does not mean that we should all descend to their levels of incompetence. Sorry for the "vent", but this wrong terminology has gone on now for 72 years; si
  16. I am a worker from/in the UK, but if TRM.40780 says, "Maternal RhIG candidacy assessment must include the identification of weak-D phenotype newborns", that is exactly what it means. It doesn't say "should" instead of "must", and it doesn't say, "until you give up because you are bored, because you have never found one"! Yes, such types are rare, but they do happen, and they can cause the mother to produce an anti-D (of sorts). These antibodies are not usually particularly clinically significant in terms of further pregnancies - but the word "usually" is the important one in that senten
  17. It is not the gel test that does not detect Partial DVI, it is the monoclonal anti-D blend in the gel that you use that does not detect those four Partial DVI types.
×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.