Auto control

[dlvannest]

Just wondering how many Blood Banks routinely perform an auto control when running an antibody panel. What do you think the benefit in this is??

[jhaig]

I can think of two reasons why we do it:

1) We use the Ortho 0.8% Resolve A. The package insert says to run an autocontrol.

2) Rule out auto agglutination seen in CAD, WAIHA, multiple myeloma, etc.

Other than that I don't think it serves much purpose...

[Hi-Freq]

Agreed, to r/o autoagglutination. Also, if you're an old bloodbanker, it's an old habit:) I think you get a good, clear, clinical picture of what's going on with the patient. As per myself here, having a hi-freq antibody, if was nice to see at least one negative reaction!

[Likewine99]

Just like jhaig said and "that's the way we've always done it!"

[ckcheng]

Perform autocontrol when you run a panel during antibody workup. If it is positive, perform DAT.

If autocontrol is positive, DAT is negative, probably the positive autocontrol is due to the testing media, repeat with another technique or no enhancement media.

If autocontrol is positive, DAT is also positive, exclude TR, or DHTR before you draw any conclusion it is due to autoantibodies. Look for mix-field reaction pattern if patient has recent transfusion.

If autocontrol is negative, perform DAT is not necessary.

Hope that helps in autoantibodies vs DAT.

CK Cheng, MSc, SBB(ASCP), CQA(ASQ)

Oct 11, 2008

[janet]

The autocontrol has also helped us with a few patients that have reacted with something in the reagent cells (preservative/antimicrobial??). As high-freq stated - it's that one negative that makes you think further.

[ckcheng]

Janet is right that when autocontrol is negative, but panel cells are all reactive makes you suspect there is an antibody against a very high incidence antigen which the patient lacks. Probably you have to send it to a reference laboratory for investigation. But, do not forget there is a type of AIHA which is DAT negative.

CK Cheng, MSc, SBB(ASCP), CQA(ASQ)

Oct 11, 2008

[OPUS104]

Like others....we do because insert advises. But the main reason is we get regular samples from our smaller hospitals that have both/all three screen cells reactive, but the two units they xm'd at the same time are compatible. We do a converted .8% ABS, prediluted .8% and auto control first thing with these samples. Regularly (and getting worse) we see reactions to some material in the reagent red cells suspensions. We also do a DAT in Gel at the same time, as your are not supposed to use DAT+ cells in Gel. (which I am sure you all know already) Auto control is also usually not going to be + with HTLAs either with pan- or near pans.....but dont get started on HTLAs, it'll make our brains hurt.

[Packer Banker]

We currently do an autocontrol for every antibody screen. I personally do not like it, as obviously, we pick up problems with the auto that we otherwise would not have seen. (These problems have no impact on the way the patient is using products.) That said, our institution believes it's important to identify every cold antibody (Anti-I, etc.), so it's consistent with that.

Where I used to work, autos were only done when the screen was positive to aid in antibody identification.

[ckcheng]

Hi Jennifer, I agree with you. Auotcontrol is not required when you perform antibody screen in pretransfusion testing. However, autocontrol does helpand should incorporate in antibody workup (antibody identification.)

Also, it is not important and necessary to identify cold antibody, that is the reason why people choose monospecific anti-IgG AHG instead of polyspecific AHG in pretransfusion testing.

CK Cheng, MSc, SBB(ASCP), CQA(ASQ)

HONG KONG

Oct 15, 2008

[PaulSunV]

We do not perform an Auto Control on ABSC but do when we are doing ABID.

[Mini Me]

We used to do autocontrol with the ABSC, but we no longer do them. The only time we do auto control is when we have positive ABSC.