Blood Types Question

[crokett]

I know there are a couple docs on the board so...

My youngest (there's a new thought!) daughter has to stay in the nursery under the blue light cause her bilirubin count is high - threshold is 3.5 and hers are 5.5 The pediatrician said it was because Mom is O+ and Jaryn is A+. O-type people can only get O blood and build up antibodies when non-O blood is introduced. Some O+ antibodies got into Jaryn (it happens). Not a big deal, they expect her to go home tomorrow as scheduled but...

Isn't O the universal blood type? If A or B can get O blood, why can't O get A or B blood? I mean I know they can't, I give blood regularly and always see the signs that O is at critical levels but why the antibodies?

[Alex Franke]

I'm not a doctor, but that's the same case that we had with both kids. It just means they may be a bit jaundiced. My son got a little yellower, and he just nursed in indirect sunlight every day for a while, which does the same thing as the light coats - vitamin D.

So I think the way is works is that A+ and B+ both have the Rh antigen (in addition to A and B antigens respectively). So, A+ can bind up anti-A and and anti-Rh antibodies. O+ has only the Rh antigen, so only anti-Rh antibodies can bind it up.

So if you start off with a lot of A with anti-B (recipient), and add a little bit of O with a little bit of anti-A and anti-B (donor), then the anti-A's are diluted and don't cause as much of a problem. But if you start off with a lot of O (anti-A and anti-B), and add a little bit of A (anti-B), then you're still going to have a lot of anti-A and it's going to bind up the cells of the donor blood.

Again, I'm not a doctor, but I think that's the way it works...

[Russianwolf]

O is the universal donor, AB is the universal recipient.

A can take A or O
B can take B or O
AB can take A, B, AB or O
O can only take O

And remember, be like my type. B+

[whitecobra]

David
You have a pretty good explanation already given but to break it down think of it this way

There are 2 different systems in blood the ABO system and the Rhesus system (named after the famous monkeys)

A person has antibodies to A B NONE or BOTH
A and B are easy O means NONE and AB means BOTH

On the other system R has either YES or NO

So the combinations are as follows
A+ A-
B+ B-
AB+ AB-
0+ 0-

If you have O negative you can donate to anyone since your blood will not react with A B AB or any variant of + or -

On the other hand if you have AB+ (like I do) you can take blood from anyone since you are resistant to reaction to the As Bs ABs and +s

You either need to receive your type or 0- (nonreactive)

If you are O- you can give to anyone if AB+ you can get form anyone

This is REALLY simplistic since there are now several more blood typing systems that are looked at when life critical donations of organs and blood are needed but this will help you for now (I hope and if not let me know)

Dr D

[Alex Franke]

I think it's O- that's universal (and rare) because it doesn't have any antigens, so the recipient won't produce any antibodies for it. O+ is next best because most people have the Rh antigen already. Similarly, AB+ is universal because it has A, B and Rh antigens and so no antibodies to bind to donor blood. AB- is almost as good because it only has the Rh antigens.

So A- can't take O+ because it only has only A antogens. When the body encounters the O+ with Rh antigens, it'll produce the anti-Rh antibodies and attack the O+ cells. A- can take O- because O- doesn't have any antigens, and A+ can take O+ because A+ alreay has the Rh antigens.

It's most significant when a mother with type O- (universal donor, no antigens) gets some blood from a first child of, say, type A+ with A and Rh antigens -- maybe during delivery -- and then builds up the anti-A and anti-Rh antibodies. Then if a second A+ baby comes along, the antibodies can attack the baby's blood pretty seriously.

As I recall, it's only potentially a big problem when mom's a negative and baby is a positive, and there's a greater risk for each additional baby.

(edit) Yes -- I see Dr. Dave beat me to it

[crokett]

Thanks for the explanation guys. I wondered where the Rh comes from. I did a little checking online last night too. Mostly I was wondering if

A) the doctor was simplifying things way down
B) I was just tired and had a slow brain
C) the doctor was just blowing smoke

I figured it was a combination of A and B.

[sacherjj]

It's most significant when a mother with type O- (universal donor, no antigens) gets some blood from a first child of, say, type A+ with A and Rh antigens -- maybe during delivery -- and then builds up the anti-A and anti-Rh antibodies. Then if a second A+ baby comes along, the antibodies can attack the baby's blood pretty seriously.

As I recall, it's only potentially a big problem when mom's a negative and baby is a positive, and there's a greater risk for each additional baby.

That was my situation as a third child. Mom is O-, Dad is A+. Both sisters before me were A+ and my moths had to take some type of drug or treatment with me because of this exact condition. I don't remember the details, I was a little young at the time.

Although all this talk takes me back to Anatomy and Physiology in High School. It was interesting getting our parents blood types and testing to find our own. Except when a girl in our class figured out that her "dad" wasn't her dad. That was interesting.