Apparently the ISBT have added this to their list: https://www.isbtweb.org/isbt-working-parties/rcibgt.html (the page still says 47 but the data tables have it added)
Blood for transfusion needs to be crossmatched against antigen types of the recipient. Many patients will tolerate several transfusions of a minor mismatched antigen before developing a sensitivity. Major antigens are what cause significant reactions that can be life-threatening.
Minor antigens come into play when crossmatching for infants and premies, but this is way beyond my scope.
I’m reminded of that American high schooler in Uganda running an orphanage and ran into this exact issue when doing a transfusion on a malnourished infant. [1]
She was skilled enough to perform a transfusion and knowledgeable enough to test for a ABO+/- match but not so knowledgeable as to be sensitive to this issue with disastrous results.
On the other hand her clinics metrics were on par or slightly above the local hospitals so it’s not clear to me they would have faired better getting care elsewhere there.
[1] https://stories.showmax.com/za/hbos-docuseries-savior-comple...
Don't we have synthetic blood, at least capable of transporting oxygen ?
How does that work? Were all three siblings regularly receiving donated blood? The article doesn't expand on this at all.
If American, think higher costs of care. If involved in car accident or other traumatic injury outside of normal area, good luck getting your blood transfused. Might get lucky with substitute. Surgery preparation also more complicated.
Maybe you have competent medical staff that recognize it. Maybe a few hematologists in the world familiar with your blood and history. Maybe a few neurons fire off in the back of an aging emergency physician that recalls this in a case study he/she read about in medical school/residency.
There are effectively millions of types because all the systems combined combinatorially, but most antigens beyond ABO and Rh don't cause that much of an issue, so in emergency cases, they just go with them.
> It's complicated.
> There are more than 35 red blood cell groups (see https://www.science.org.au/curious/people-medicine/blood-typ... for a nice writeup). For each of those blood groups, there is more than one possible configuration of some protein or carbohydrate (something like more than one possible genetic sequence leading to more than one kind of molecule on the surface of the RBCs).
> And, even with ABO, there can be infrequent variations that make things more complicated (see https://professionaleducation.blood.ca/en/transfusion/best-p... for more).
> For the other blood groups, I think every case the groups were identified because a patient somewhere made an antibody, causing either a transfusion reaction (if not tested ahead of time) or, more likely, a positive (incompatible) reaction on in compatibility testing.
> [...]
It's worth reading the full original comment because it has more interesting details https://news.ycombinator.com/item?id=33507052
Which makes the hollywood trope of ‘i’m a universal donor’ really silly. Universal donor of what? And then they pump the blood and plasma straight into the other person pretty much guaranteeing problems since either the blood or plasma will be incompatible. The only reason blood donation works is due to machines that separate the blood and plasma.
We don't actually express antibodies to antigens until we're exposed to them, so crossmatching won't detect a minor antigen mismatch until the first transfusion containing the antigen is administered.
That first time causes a delayed hemolytic transfusion reaction, which is generally milder than the kind of reaction crossmatching will prevent, but can be serious or even fatal.
https://en.wikipedia.org/wiki/Delayed_hemolytic_transfusion_...
Depending on the severity of the reaction, blood will either be stopped or the patient will be loaded up with Benadryl and Tylenol with the blood running at a slower rate.