QC on panel cells

[ElinF]

This may be dunb, but does anyone QC their panel cells? I saw the thread about using Expired reagent panel cells, and this question was brought up by one of our staff. We QC everything else, but honestly not panel cells. Do you QC all 11, or just 1? Never really thought about this. They just work...

[ElinF]

I see another thread on this topic so I will read through that. Sorry!

[jill]

This may be dunb, but does anyone QC their panel cells? I saw the thread about using Expired reagent panel cells, and this question was brought up by one of our staff. We QC everything else, but honestly not panel cells. Do you QC all 11, or just 1? Never really thought about this. They just work...

We QC each new lot of panel cells (gel and tube) prior to use using a positive reagent control

and a negative(Monocontrol) on each vial. If we use an expired vial from a gel or

tube panel to rule out or in we QC this panel cell by testing it with the appropriate

anti sera.

[John C. Staley]

I'm curious, on what, do you base the need to QC panel cells? Do you test each cell for every antigen noted to confirm if they are really positive or negative for the antigen??

Any thing less would be just smoke and mirrors to make it look like you are doing something!!!

[L106]

Way-to-go, John!

You know, I'd really like to see a show of hands of those who do QC on new lot #s of panel cells and have ever found the panel cells to be "Unacceptable" based on that QC? (Personally, I have never heard of this happening.)

Donna

[ElinF]

Way-to-go, John!

You know, I'd really like to see a show of hands of those who do QC on new lot #s of panel cells and have ever found the panel cells to be "Unacceptable" based on that QC? (Personally, I have never heard of this happening.)

Donna

I have always wondered about the QC on panels thing, but never had the guts to ask! I am glad not many other people do it.

[ANORRIS]

This is right up there with having to do an IS XM with every Gel XM......geez!

[ElinF]

This is right up there with having to do an IS XM with every Gel XM......geez!

I know, right! However, it is dumb, but we still have to do it.

I just posted a comment last night- I had a joint commission surveyor ask me if I QC'ed our panel cells and she was surprised that we didn't! She was giving me all sorts of grief so I answered with basically what John said earlier. She still wanted me to check with my reference lab, which I did and they were surprised as well, as they do not QC them either...

We did not get cited.

interesting.

[Auntie-D]

We QC all of our reagents every day against a weak-D and Kell control. I would not be happy if any of my staff were using reagents without checking their viability first...

[L106]

We QC all of our reagents every day against a weak-D and Kell control. I would not be happy if any of my staff were using reagents without checking their viability first...

Just curious.......Are the results of this QC ever "Unacceptable?"

[tbostock]

There is no regulation to QC panel cells, so we don't do it.

[Auntie-D]

Just curious.......Are the results of this QC ever "Unacceptable?"

Never yet 'unacceptable' but it has allowed us to identify cells that are trending to weakness. All of our cells give a 3+ reactivity and if this falls and the reagents have more than 10 days expiry we replace them rather than waiting for the new batch. So the answer to you question is 'No' but without the action taken for trends the answer could have been different. In 2 and a half years as blood bank manager we have had to replace a batch early (and at no cost) twice, due to weakening of reactivity. The consequence of weak reaction are not something I want to take responsibility for.

Edited September 29, 2011 by Auntie-D

[Auntie-D]

There is no regulation to QC panel cells, so we don't do it.

There is a regulation in the UK to QC screening cells daily and the MHRA extend this in their inspections to include the QC of all antibody screening reagents, whether 3 cell screen, rr 2 cell screen or panels.

Even for countries where it isn't regulatory to QC reagents daily, it is good practice...

[jeanne.wall]

I think this is a place to use some of the knowledge we’ve gained over the years. Definitely when you consider reagent red cells reactions, you need to understand the limitations – no one can assure the antigen status for every antigen that there could be on a red cell! We also know that antigens have different characteristics and behaviors – some stay on red cells better than others; some have a wide range of the number of antigen sites on the cell surface – really many, many different things can be going on. So, why do we do QC and what are we trying to demonstrate. On screening cells we do QC because these are the cells that in most laboratories get “abused”, often sitting unrefrigerated, on a counter for hours on end. QC serves the roll of showing that the cells are intact and behaving in an expected way. We want a positive reaction. It doesn’t tell us much, we are only testing with one or two antibodies, but it does show that the cells are able to behave in an expected way. Panel cells generally don’t face the same “abuse” as screening cells, only coming out of the refrigerator when they are needed. It is actually easier to know that the cells are working, you expect a positive reaction for some of the cells and you usually get the positive reactions that you then use to identify the specificity of the patient’s antibody.

I think we understand the there are limitations with reagents and with our efforts to “QC” these particular reagents. So when you see something that doesn’t make sense, an unexpected positive reaction or a negative reaction where we thought it should be positive, we think about it, we investigate it, and we understand it. This thought process always includes “is there something going on with a cell – is it contaminated, has it lost an antigen, what is going on in this particular test tube. We can’t just think about the patient’s sample when we use red cell products, even though we spent money to buy them and have some expectations about them, every red cell used in a panel or as a screening cell came from an individual donor. Add to this mix, how they are manufactured and handled - just too many variables – that is why they have us around to have the knowledge to understand all of the potential things that can be happening. I think rather than worrying about how to QC these products, we need to worry more about how do we help the technologist with limited experience understand all the dimensions that we need to consider when we use these products.

[SMILLER]

I have wondered about this before (but never investigated it until now), thinking that it was impractical and/or unecessary as far as regs go but...

Looking at the product insert for our gel AB panels, it says under "CONTROL OF ERROR"

"For quality assurance, 0.8% RESOLVE Panel A should be tested periodically with weak antibodies."

Now I am not sure about FDA regs, but I would think that JCAHO would be upset if they knew any test system was not being QC'd per manufacturer's recommendation.

Having said that, I think I can kinda see where this is all going. We test screening cells every day. But how can we be absolutely sure that the panel cells we are using for rule-outs actually have detectable AG on them?

I agree with some of the ideas here that a comprehensive QC of a panel is impractical. But a documented check at a certian point - say a week or 10 days before the panel expiration date - that consists of one or two weaker antigens known to deteriorate would satisfy any inspector. (That is, if an inspector even makes a point of it, which has never happened at my Lab that I know of.)

Does this make any sense? I guess I am struggling to find a middle ground here.

[Eagle Eye]

we are not talking about screening cells...In US we do have a requirement to QC our screening cells daily. We are talking about antibody identification reagent cells/panel cells such as panel A, B, C or immucor pano 16 etc.

[rbayliff]

I had seen the reference to QC our panel cell periodically in the package insert. When I called our reference laboratory, they confirmed that they do QC their panels when they receive them. Since they have access to weak antibodies, they freeze plasma specimens to use as QC. Since we don't have access to some of the less frequent antibodies, we used a diluted antisera to create a weak reaction. They informed me they do not do a positive and negative for each cell, just prove that the panel is able to identify the known antibody.

[SMILLER]

Terri

Just quick question for you if you don't mind. We use Ortho for our gel panels and Immucor for our tube, and both manufacturer's inserts say to test panels with weak antibodies. What do your inserts say?

[rebeccarjthomas]

For many years, I worked in a Ref Lab that chose to QC each of our In-house panel cells daily. This was done in response to an inspector's suggestion. We made sure that each panel cell was used in some part of the general daily QC (o cell for anti-AB, test cells for each enhancement with weak aby, neg cell with AHG reagents). Becky

[tgambill]

I am a new blood bank supervisor and thought I would check here to see what everyone is saying about panel qc. the last place i worked did not any panel qc, but this place does an anti-D positive control on cell 1 and a negative control on cell 1 every time the panel is used (but they only do it on the "in-date" panel and not on the panel they use for selected cells). the CAP checklist say all reagent cells must be checked for reactivity and specificity each day of use. this has me completely confused. i am not sure what I am qc'ing. if I use anti-D, ok, great I know that my D antigen is on cell 1, but this really doesn't tell me anything about the other cells or antigens. Any thoughts/input would be appreciated.

[Auntie-D]

I am a new blood bank supervisor and thought I would check here to see what everyone is saying about panel qc. the last place i worked did not any panel qc, but this place does an anti-D positive control on cell 1 and a negative control on cell 1 every time the panel is used (but they only do it on the "in-date" panel and not on the panel they use for selected cells). the CAP checklist say all reagent cells must be checked for reactivity and specificity each day of use. this has me completely confused. i am not sure what I am qc'ing. if I use anti-D, ok, great I know that my D antigen is on cell 1, but this really doesn't tell me anything about the other cells or antigens. Any thoughts/input would be appreciated.

The Anti-D pos and neg is the control you need to do for every batch to control the methodology. This is in addition to a single daily QC for all reagents and cards in use.

For the first batch of the day we set up a weak control, either D or K (we alternate each day) and challenge all grouping and screening cells and reagents. Just treat your whole blood control like a patient and it simplifies the whole thing

[rravkin@aol.com]

I think this is a place to use some of the knowledge we’ve gained over the years. Definitely when you consider reagent red cells reactions, you need to understand the limitations – no one can assure the antigen status for every antigen that there could be on a red cell! We also know that antigens have different characteristics and behaviors – some stay on red cells better than others; some have a wide range of the number of antigen sites on the cell surface – really many, many different things can be going on. So, why do we do QC and what are we trying to demonstrate. On screening cells we do QC because these are the cells that in most laboratories get “abused”, often sitting unrefrigerated, on a counter for hours on end. QC serves the roll of showing that the cells are intact and behaving in an expected way. We want a positive reaction. It doesn’t tell us much, we are only testing with one or two antibodies, but it does show that the cells are able to behave in an expected way. Panel cells generally don’t face the same “abuse” as screening cells, only coming out of the refrigerator when they are needed. It is actually easier to know that the cells are working, you expect a positive reaction for some of the cells and you usually get the positive reactions that you then use to identify the specificity of the patient’s antibody.

I think we understand the there are limitations with reagents and with our efforts to “QC” these particular reagents. So when you see something that doesn’t make sense, an unexpected positive reaction or a negative reaction where we thought it should be positive, we think about it, we investigate it, and we understand it. This thought process always includes “is there something going on with a cell – is it contaminated, has it lost an antigen, what is going on in this particular test tube. We can’t just think about the patient’s sample when we use red cell products, even though we spent money to buy them and have some expectations about them, every red cell used in a panel or as a screening cell came from an individual donor. Add to this mix, how they are manufactured and handled - just too many variables – that is why they have us around to have the knowledge to understand all of the potential things that can be happening. I think rather than worrying about how to QC these products, we need to worry more about how do we help the technologist with limited experience understand all the dimensions that we need to consider when we use these products.

Jeanne,

Thank you for this post. I would wonder about the expired panel cell's viability when we are forced to utilize these cells. I had asked about the need for QC of the expired panel cells the other week. It seems only logical that one would want to know difinitively that this expired cell still maintains the viable antigen we are testing for. As you mention the cells break down over time and may lose the very antigens we need them for. I am not saying to QC the expired panel for all antigens at one time but rather QC the specific cell that is being utilized for the antigen for which we are testing. If we get a negative result with this cell we are only saying that it is negative do to a lack of antibody specificity; but we can not say that the test is negative do to a lack of viable antigen because we are not running a control to test for the presence of the antigen for this expired panel cell in the first place which could lead to a false negative result. The answer I recieved when I asked about QC of the expired cell is that we are not doing that yet. So it seems a logical step that if we are going to persistantly use expire panel cells than we are going to need to prove the viability of the antigen for which we testing at some point; it is just good scientific practice.

Edited October 31, 2011 by rravkin@aol.com

[Malcolm Needs ☆]

The problem comes, of course, when you are using the cell as a negative (a Kp(b-), for example). Just because the Kp(a) antigen is still viable.......................

[rravkin@aol.com]

The problem comes, of course, when you are using the cell as a negative (a Kp(b-), for example). Just because the Kp(a) antigen is still viable.......................

Hey Malcolm,

Thank you for the response. In the hospital practice we usually use expired panel cells that are positive for an antigen and perhaps negative for others. There really is no questioning the negative antigen but we would want to know that the postive antigen is still viable so that when we obtain no reactivity we can have some assurance that it is do to a lack of, antibody specificity not antigenicity.

[Malcolm Needs ☆]

I know. I was being naughty and playing Devil's advocate!!!!!!!!!!

I shouldn't do that.