Tabbie

Yes I should have added allo anti-C. Also thought may be anomaly if both allo anti-C and allo anti-Cw were detected like ceppellini effect but there is not. Thanks for clarity

Thank you So if you had an autoantibody and multiple clinically significant alloantibodies confirmed by phenotype (genotype if required) including let’s say for example anti-C you would not perform further exclusions for anti-Cw ?

Hi All So if you had a patient with an auto antibody you would rule out all antibodies even clinically insignificant to confirm any underlying allo antibodies. However if anti-Cw was detected you would ordinarily give crossmatch compatible BUT you are giving antigen positive units due to auto so crossmatch would positive ? Therefore what do you do ? crossmatch anti-Cw negative units ? Realise not clinically significant but ordinarily if crossmatch was positive you would not give that unit to the patient? You would select another unit. Thanks

Your a star Malcolm as ever complex but clear and reference to the GATA-1 gene to compare scenarios, putting it into perspective. Much appreciated

Hi Malcom When you say mimic does that mean that the patients phenotype would not be E+ or e+ which would be the case if it was just an auto anti-E (wondering about how sometimes phenotype is not the same as genotype). Or would you not know until you performed adsorption/elution with D—/D— to confirm the Rh17. Thanks

Hi All So if a patient who is a D Variant (weak/partial) that can produce Anti-D is subsequently immunised with D positive RBC. The auto and DAT would be negative usually ? However anti-D causes extravascular haemolysis so DAT should be positive. Is anti-D produced from a D-Variant any different in strength/avidity. Realise that pos DAT can occur for other reasons AIHA etc. Can anyone explain the mechanism of the anti-D anomaly? Or a link to an article ? Thanks

Great thank you 😀

Hi All Would anyone have a method for this neutralisation technique ? Thanks

Thanks Galvania All made up so if you don't ever see something I have 'made up' please let me know. I was trying to fit lots of questions into one scenario.

Thanks for your time yes very helpful. I will keep read

So for example the question below If you only knew that the patient had been transfused but no other details how would you phenotype or would you just obtain a genotype? The BSH guidelines say " If the patient is known to have been transfused in the previous three months, phenotyping may be misleading" Most regularly transfused patients such as Haemoglobinopathy patients admittedly would already be phenotyped but if they were not they would required Rh K matching units, DARA patients would you Rh phenotype if units are required ASAP but you have time for a crossmatch. What further tests would you do if you had the resources to ensure you provided matched units So for example after the elution to identify the antibodies can you use the RBC left from the process to phenotype ? or does the elution damaged the RBC is there another procedure for phenotyping if the patient has been recently transfused? Misleading means ? - What anomalies would you actually see ? weakened reactions, dual populations (if ABO) anything else? Why with warm autoantibodies does elution not help ? What about in pregnancy are there any anomalies with elution/adsorption/phenotyping ? Thanks

I work in a small lab we just don't get the experience of the unusual. I am trying to learn more by posting hypothetical case studies as I cant post real ones. Thanks

Great thanks Galvania More questions If it was an anti-I would the pattern be pan-reactive by IAT weaker and Enzyme stronger reactions? If patient was previously transfused would you phenotype RBC if you knew the group of the ABO mismatch i.e. if a dual population say Group A given to a group O? Would you perform an eluate to remove the antibodies then add anti-A to remove the A RBC then phenotype the O RBC and assume they are the patients RBC as the phenotype? If you only knew that the patient had been transfused but no other details how would you phenotype or would you just obtain a genotype? If no mix field and DAT C3d only and Donath Landsteiner test was positive would you then titer with P antigen positive RBC? Cheers

Thanks Malcom for reply it was a while ago and I didn’t cite it as I thought I would come across more that would explain it. But looks like from you reply this is not possible. If I come across it again I will post.

Hi All Hypothetical Senario Female patient unknown transfusion history with mycoplasma pneumoniae what exclusions and further testing would you perform ? When would you perform a titre ? Reactions greater than 3+. If emergency units required with titre greater than 64 what is your protocol ? Thanks