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Gel Card QC


skroc

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We are a smaller hospital just implementing manual gel testing for blood types and antibody screens. Would anyone be willing to share what they are using to QC these cards? Is it a commercial kit versus in-house reagents?

Thanks!

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We are using Ortho gel cards with the same QC material that we had used before switching from tube (which is Immucor corQC). As suggested by Ortho during our gel training, we use the MTS diluent as a negative control, and dilute the QC serum 1:8 with albumin to give us 2+ to 3+ positive results with gel.

Scott

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Same as SMiller. We use A2 cells and check cells for negative and positive controls for the diluent. If the cekck cells are negative it indicates possible contamination of the diluent.

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When we use diluent for a neg control, we are using the gel screening cells with them, just like we use the screening cells with our corQC plasma for a positive control.

Unless you check the screening cells with something that is going to give a negative reaction, it does not seem like you are QCing the screening cells properly.

Scott

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We use Ortho Confidence System and dilute the serum 1:16 to yield a 1+ - 3+ reaction. We aliquot and freeze the diluted serum for daily QC. We run a known negative patient for the negative control. We QC the diluent by performing a compatible and an incompatible crossmatch using patients and rbc's of known compatible and incompatible types.

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We also use Ortho confidence diluted 1:10 w/ albumin and diluent for the neg control but I can't find the standard requiring the reaction strength of 1-3+ Can someone tell me where to find the standard that requires a 1-3+ reaction for the positive antibody screen QC. Is it AABB, CAP or ???

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I use the Immucor CorQC and dilute the QC serum 1:10 with albumin and use the MTS diluent for the negative control.

Thus altering the equilibrium constant and, as I have said many times on this site, rendering the Quality Control useless as anything but a sop! Sorry MAGNUM - it's not just you - you just happen to be the latest.

A DILUTED ANTIBODY IS NOT THE SAME AS A GENUINE WEAK ANTIBODY.

Everyone who does this should read Harvey G. Klein and David J. Anstee, Mollison's Blood Transfusion in Clinical Medicine, 11th edition, 2005, Blackwell Publishing, Chapter 3.

Now the good news. I was talking to Dave a few weeks ago, and he was telling me that their 12th edition should be out later this year.

Edited by Malcolm Needs
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Thus altering the equilibrium constant and, as I have said many times on this site, rendering the Quality Control useless as anything but a sop! Sorry MAGNUM - it's not just you - you just happen to be the latest.

A DILUTED ANTIBODY IS NOT THE SAME AS A GENUINE WEAK ANTIBODY.

On one hand, this seems to be a valid point. On the other hand, no QC material, serum or cells, can be said to be "geniune". If I am not mistaken, they all have been manipulated and contain adulterants to extend shelf life.

On the third hand, we also use a 10ul QC serum to 8 drops 22% albumin to get a 2+ to 3+ reaction with our 0.8% screening cells in gel. The screening cells insert only says to test each day of use with "weak antibodies"--it doesn't specify how to get them. I am thinking the main point is to prove that you can pick up a weaker reaction with the gel/QC cells--not too knock oneself out trying to replicate what happens with a live patient.

We have had several inspections since switching to gel--no-one has questioned this technique for QC.

On the fourth hand... oh, forget it, I'm already out of hands!

Scott

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Thus altering the equilibrium constant and, as I have said many times on this site, rendering the Quality Control useless as anything but a sop! Sorry MAGNUM - it's not just you - you just happen to be the latest.

A DILUTED ANTIBODY IS NOT THE SAME AS A GENUINE WEAK ANTIBODY.

Everyone who does this should read Harvey G. Klein and David J. Anstee, Mollison's Blood Transfusion in Clinical Medicine, 11th edition, 2005, Blackwell Publishing, Chapter 3.

Now the good news. I was talking to Dave a few weeks ago, and he was telling me that their 12th edition should be out later this year.

Finally, someone references a bit of literature that I happen to have in my office! I'll give her a look.

Our gel QC consists of

Saline vs. screen cells

1:1000 dilution of anti-D w/ albumin vs. screen cells

anti-A vs. 3% A2 cells converted to 0.8%

anti-B vs. 3% A2 cells converted to 0.8%

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On one hand, this seems to be a valid point. On the other hand, no QC material, serum or cells, can be said to be "geniune". If I am not mistaken, they all have been manipulated and contain adulterants to extend shelf life.Scott

Sorry Scott, you are going to HATE me, but NHSBT "produce" genuine weak anti-D, anti-c, anti-K and anti-Fya for this purpose.

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We use Ortho-CQI-7 ( internal quality control which we recived comercially from ortho company ) having 4 blood group with phono type and 3 IAT serum . and we do DAT+ control same provided by ortho .

manually we have made positive DAT sample , and we Run O neg and AB+ known blood group to check the card validity .

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In the U.S., the 1+ to 3+ requirement for positive control for QC of antibody screening cells came from a CAP requirement in years past. We use the Ortho Confidence Kit which has a positive control that contains a mixture of anti-D and anti-c. The antibodies will typically react 1-3+ with screening cells if doing manual tube antibody screen but will react 4+ in Gel testing. CAP has dropped the 1+ to 3+ requirement and we now use the positive control as provided.

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I believe the CorQCs package insert states the average result for the positive antibody screen control was 1+ to 3+. And for the limitations it states that - results seen less than their average is deemed unacceptable. It doesn't say it's unacceptable if you get a 4+ reaction. And of course their package insert is in regards to tube testing.

I have been wondering though, when a manufacturers package insert says "should be" does that mean it is required or optional? If anyone can shed some light on that, it would be greatly appreciated! :)

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