AuntiS

One of the only ways to detect Ko blood (apart from by molecular means - that still have to be proved serologically) is by use of the indirect antiglobulin technique (as you well know)!

What's wrong Malcolm ? You don't like the idea of using a Coombs Test to find Kell- blood ??

The reagent we use includes instructions that only specify a positive reaction is required.  It does not give a minimum grade. 
I remember being taught 2+ many years ago, but we now only require macroscopic agglutination.
sandra

The reagent we use includes instructions that only specify a positive reaction is required.  It does not give a minimum grade. 
I remember being taught 2+ many years ago, but we now only require macroscopic agglutination.
sandra

The reagent we use includes instructions that only specify a positive reaction is required.  It does not give a minimum grade. 
I remember being taught 2+ many years ago, but we now only require macroscopic agglutination.
sandra

Nice !!! Old School.

If you put a drop of blood on something like a filter paper, and then add a drop of 1M NaOH, if it is adult blood, after a couple of minutes it will turn a sort of yellow/brown colour, as the Hb is denatured by the alkaline, whereas, if it is blood derived from the baby (including cord blood), the red cells will stay red, as HbF is not denatured by the alkaline for much longer.
It is rather like doing a Kleihauer, but by "bucket chemistry", as it is known!  

Sorry, but can I just point out that you should be sending out the tests if the patient is a female of child bearing POTENTIAL, rather than child bearing age.  If the female is four (for example), she is not likely to be of child bearing age, but she will be one day, and if she is an individual who has a Partial D type who can produce an anti-D, she deserves as much care as does a female of, for example, 25 years.

If you are seeing a lot of weak results in your anti-D well that subsequently turn out to be negative, I suspect the reason to be one of manipulation rather than anything serological.  I would guess that NONE of these babies are group O.  I am guessing that you are seeing carryover from your anti-AB.  It can happen that if cards are stored somewhere where condensation can take place then drops of antiserum can condense into the reaction chamber and 'jump' into the next well or even next 2 wells when you remove the aluminium.  This can cause false positive results.  I suggest you check the cards before pipetting in them and see if there are any signs of these drops.  Don't use the cards if there are and look for another place to store them

There are one or two comments I would make, which you may find pedantic, but, that notwithstanding, they are true.  There is, and never has been, a blood group system named Rhesus.  Rhesus was an ancient king of Thrace.  The correct name for the blood group system is Rh.  So, it is the Rh Blood Group System, the two genes involved are RHD and RHCE, the carrier proteins are RhD and RHCcEe, but the antigen of which you are talking is just plain D, and not Rh D.
There is a very good reason why the instructions that come with the anti-D state that the tests should be read macroscopically.  Thorpe et al, in two papers, reported that monoclonal anti-D molecules possess a V4-34 moiety, that is also present in anti-I and  anti-i. As a result, if papain-treated D- red cells are tested with such antisera, or untreated D- red cells are tested with such antisera that have not been brought to room temperature, they may agglutinate.  This could result in D- red cells being mistyped as D+ - a particular danger in females of child-bearing potential, and babies (Thorpe SJ, Boult CE, Stevenson FK, Scott ML, Sutherland J, Spellerberg MB, Natvig JB, Thompson KM.  Cold agglutinin activity is common among human monoclonal IgM Rh system antibodies using the V4-34 heavy chain variable gene segment.  Transfusion 1997; 37: 1111-1116, and Thorpe SJ, Ball C, Fox B, Thompson KM, Thorpe R, Bristow A.  Anti-D and anti-i activities are inseparable in V4-34-encoded monoclonal  anti-D: the same framework 1 residues are required for both activities.  Transfusion 2008; 48: 930-940).
In addition, if you do not follow the manufacturer's instruction, and something goes wrong, under UK (and EU) Law, you could well be liable, as described by Bob Doughty some 30 years ago now (Doughty RW.  Product liability in the medical laboratory.  Medical Laboratory Sciences 1989; 46: 68-71.
In the case that you describe, do you know the Weak D type of the baby (it may well be Weak D Type 2, which can be particularly weak) and, at any time, did you test the mother's red cells to see if she was also a Weak D of the same type?  If she was, then it is highly likely that anti-D immunoglobulin would not have been required anyway, although I am aware that this is not part of the BSH Guideline (White J, Qureshi H, Massey E, Needs M, Byrne G, Daniels G, Allard S and British Committee for Standards in Haematology.  Guidelines for blood grouping and red cell antibody testing in pregnancy.  Transfusion Medicine 2016; 26: 246-263.  doi: 10.1111/tme.12299).
My honest advice is that you do not read the tests under a microscope.  If you have ANY doubt, give the mother anti-D immunoglobulin anyway - it is not that expensive, and has a good safety record in terms of TTI.
.

No guidelines, just clinical common sense.  There are absolutely no data to support the need for excluding heterozygous donors, nor the need for heterozygous recipients to receive only AA blood.  Heterozygous patients are physiologically normal except for some data to suggest that under extreme conditions of dehydration, altitude they are slightly more susceptible to complications that occur even among hemoglobin AA patients.

But what is the acceptable temperature limit for a 30 minute excursion? If it was in a validated transport box with a logger inside that remained between 1oC and 6oC then it wont be considered to have left cold storage hence the 30 minute rule wouldn't apply.  We have transport boxes validated for 8 hours that we send to OR. So that fact that a limit to "30 minutes rule" exists suggests that the unit does not need to be kept at cold storage temperatures, but what would be acceptable? temperature for the unit to reach for 30 minutes? For example UK guidelines state that a unit of PRBC can be used with temperature excursion of up to 10oC for up to 5 hours. 
Some interesting info in this document for the UKBTS reviewing the evidence of various studies,
https://www.transfusionguidelines.org/document-library/documents/change-notifcation-no-33-2016/download-file/Change Notification No 33 2016 - Removal of red cells from a controlled temp.pdf
Ramirez-Arcos and colleagues from the Canadian Blood Service reported on two studies
using red cells in SAGM. In the first study, a single five hour exposure to room temperature
showed no immediately significant effects on the in vitro quality of the red cells, although six
days after the exposure ATP and K+ levels were significantly lower than in unexposed
controls[22]. In the second study, units were exposed to room temperature for 30 minutes
on each of five separate days, and no significant effects on in vitro red cell quality markers
were reported[23].
 
Steve
 
 

I totally agree, but, in the UK we are "governed" by the recommendations of the The Advisory Committee on the Safety of Blood, Tissues and Organs (SaBTO), and they say that we have to actually use CMV- tested blood and blood components for certain patients (including pregnant women), in addition to them being leukodepleted.

Really Malcolm? 

I am an idiot!  I will try to edit my original post.  Thanks for pointing out my error BankerGirl.

https://www.nacblood.ca/resources/guidelines/CMV.html
These are the Canadian National Advisory Committee Guidelines for use of CMV Negative Blood Products.
 

Agreed, and you are also in a position to argue with them (slightly, and politely).

Here, a temp >1 degree Celsius over baseline AND any other symptom gets an automatic culture.  Plus I suppose we would honour any direct request for a culture (not that I've seen that happen). 

Actually, the D mosaic phenotype, where some red cells appear to be D Positive and some D Negative, is more common than many people think.  This has nothing to do with the individual having a genotypic mutation, per se, but is more to do with the mutation of a particular clone of red cell production within the bone marrow; it does not necessarily mean that there is any underlying clinically significant pathological condition.

The problem is that it is almost impossible to demonstrate a D mosaic without going through the whole rigmarole of testing that you describe.  However, there are anti-D kits available that will show, to all intents and purposes (with the exception of Partial D Type III - which is an exulted D type anyway, despite being a Partial D type) that there is a mosaic there (mixed-field reactions with all reagent anti-D sera), rather than a Weak or Partial D (usually a clear positive or negative reaction with the individual reagents).  Such kits are not cheap in themselves, but I doubt if they are as expensive as $750.

Also, do you have any references to help me make sure I understand the mosaic mechanism vs. chimera?  If I follow you, chimeras would have a mixed red cell population from the embryo stage but a mosaic might have had a spontaneous mutation in a red cell precursor line at a later time. Is that right?  Is this similar to how it works for people whose D antigens weaken with leukemia?
 
 

Hi Mabel,
Yes, I was referring to the Alba Partial D kit.
In addition, yes, you are quite correct in what you say about the difference between a "true" chimera and the spontaneous mutation and your comments about leukaemia.
The best I have read on this is in Daniels G.  Human Blood Groups.  3rd edition, 2013, Wiley-Blackwell.

Hello Eva,
The thawed codes for E1624 are listed below. I have included the codes for products with a 24 hour expiration and 5 day expiration, in case you need both. You can use the ISBT 128 Product Lookup Web Application to look up the full descriptions.
24 hour expiration: E2284 5 day expiration: E2121 The division codes (A0, B0, C0, etc.) would also use the same 5-character thawed Product Description Codes. I also wanted to clarify that the second character of the division code is a “0” (zero), and not the uppercase letter “O”. Section 5 in the Implementation Guide: Use of Product Code [Data Structure 003] - Blood (IG-021) document further discusses division codes. (Please note, you will need to be logged in to view the document).
I hope this helps, Eva! Please let me know if you would like some more help with finding additional codes.
Kind Regards,
Kaytee from ICCBBA (Organization that maintains and develops the ISBT 128 Coding and Labeling Information Standard)
 

Wanna learn a site trick?  If you type the @ symbol followed by their user name, the user usually gets an email notification with a link to this thread.  Like this:: @galvania.

There are microscopes that have a contraption that can be attached to the stage, where there are two sort of parallel metal bars that are just far enough apart from one another that a tube can lie between them, but the sides of the tube just lie on the metal bars, rather than on the stage itself.  The bars are also slanted, so that the contents of the tubes slide towards the tube opening (but not slanted sufficiently to allow the contents to spill out).  The trick is to get  the contents of the tube in focus.
The contents of the tube has to be examined under low power, otherwise all tests will appear positive.  In over twelve years of using such a microscope, I found it useful just once, when I was dealing with an anti-Lub, as it showed the distinctive Lutheran type of agglutination.  Other than that, there was no occasion when looking down such a microscope helped me in any way.  However, Peter was NOT suggesting that a microscope should not ever be used to read a serological test, but suggested that such use should be exceptional, rather than the rule.

And never EVER , under ANY circumstances look at gel tests under a microscope or a magnifying glass - unless you want to call absolutely everything positive and waste everybody's time