Lot to Lot Comparison

[mld123]

Anyone doing lot to lot comparisons for Blood Type and Antibody Screen reagents?  If so, do you have a form you would be willing to share?  I took over from another supervisor who started the staff performing lot to lot comparisons, but there is no procedure or form they are currently using.  They are taking the normal daily QC sheet and highlighting the new vs. old lots they used.

 

Thanks in advance for any help with this.  Also, if you are not doing lot to lot comparisons have you gotten dinged from CAP?  My previous employer had an inspection where this was a hot button issue at the time.  I just want to make sure I am doing it correctly.

mld123

[jalomahe]

We do not do lot to lot comparison on blood typing antibody screen or antibody identification reagents. These are FDA licensed reagents and had to be approved by the FDA prior to release from the manufacturer. We have never gotten dinged by inspectors for not doing it.

 

[DebbieL]

I called CAP and this is not a requirement for regular BB reagents because we do QC each day of use. Plus think of all the drops of precious rare antisera we would use trying to compare lots.

This comparison requirement is mostly for Chem or Hemo because they are not required to perform QC each day and their tests are more of a "range" test. They have to make sure that the "range" is the same between lot numbers or they could report out erroneous results. With BB you are either positive or negative. You either have it or you don't.

CAP did tell me we must compare "kits" lot to lot. This would be FBS kits and Elu-Kits or any other kits you might use. I was sad we had to do this but happy that we didn't have to compare all other reagents.

[mld123]

I contacted CAP today and they stated that the lot to lot comparison does not apply to any transfusion service related reagents including kits.  I specifically asked about the Fetal Screen Kit and they said it is not required.

I may change our procedure to only the kits and not any of the other reagents just to be on the safe side.

 

thanks!!

[Liz0316]

really?! well that changes things. Can't wait to discuss this with my inspector this year. I would love to eliminate just one thing!

Liz

 

[Marianne]

The fact that some of us are getting conflicting information from CAP is a bit concerning.  We implemented the lot to lot on Fetal kits a little over a year ago after being told it was required (like DebbieL).  I would hesitate to drop that one unless I had it in writing from Denise Driscoll at CAP that it is not required.

[mld123]

Yes, I am leaving the Fetal Screen Kit but am getting rid of everything else. I am hesitant to get rid of the comparison on the Kit just in case someone else inspects us next time that is doing this.

 

 

[David Saikin]

comparison on that kit is easy to do (Fetal Screen);

I won't be comparing the elution kits until "forced".

Edited March 15, 2016 by David Saikin
adding stuff

[goodchild]

Unless you're being inspected by a CAP-employee inspector, you should take some inspection findings with a grain of salt.

1 hour ago, mld123 said:

Yes, I am leaving the Fetal Screen Kit but am getting rid of everything else. I am hesitant to get rid of the comparison on the Kit just in case someone else inspects us next time that is doing this.

 

 

 

[tbostock]

2 hours ago, Marianne said:

The fact that some of us are getting conflicting information from CAP is a bit concerning.  We implemented the lot to lot on Fetal kits a little over a year ago after being told it was required (like DebbieL).  I would hesitate to drop that one unless I had it in writing from Denise Driscoll at CAP that it is not required.

That's because they are usually peer inspectors and they all have different ideas and practices at their laboratories.  I would agree with Marianne and get something in writing.

I have had discussions with inspectors over the years over the lot-to-lot thing.  So far I have prevailed.  We just do it for Fetal kits and RPR reagents.  Yes, we still do RPR in the Blood Bank (ugh).

[galvania]

Actually it doesn't make any sense to compare one lot of screening cells with another one.  they won't be the same.  They CAN'T be the same - they won't be the same donors.  so the antigen profiles will be different (although there are usually some phenotypes that are 'fixed'), and the antigen density of the cells will have the normal variation found in the normal donor population.  You should expect to see a certain difference

[Dr. Pepper]

I agree with all that it makes no sense. It does make sense for quantitative tests, like glucoses and platelet counts, are essentially the same from lot to lot. But testing new qualitative serology kits against the controls of the old lot and vice versa is pointless.

That being said, this is interesting news because I asked CAP on 6/15 if we had to do lot to lot and they said yes indeed. Here's my question and CAP's response if you're patient enough to wade through it.

---- Original Message ----

Name: Mr. Philip Hoffman  The customer sent us the following question or comment: Hi - I have a question as to how COM.30450 New Reagent Lot Confirmation of Acceptability pertains to routine blood bank reagents, many of which are approved by the FDA with a defined potency before release. Do you have to run new and old lots of reagent antisera, both routine (anti-A, anti-D etc.) and rare (anti-K, anti-Jkb etc), and antiglobulin reagents, together against positive and negative cells OR will just testing them against appropriate control material on each day of use suffice? How about reagent red cells, do they need to be tested against antibody-containing material or will routine daily QC suffice? Can they be tested against reagent antisera or do you need patient samples? Do panels have to be performed old and new lots against a random antibody? Thank you. Phil Hoffman

Hello Philip,

 

For COM.30450, the intent is to check a new lot and/or shipment of reagents before use in patient testing in order to confirm that proper shipment conditions were followed (to the best of the lab’s ability), and that the new lot of reagents gives the same results that your old lot did. This applies to all reagents, routine and rare. As COM.30450 includes below, external QC materials tested on the previous lot, and compared to the same material tested on the new lot, is acceptable. Reagent cells can be tested against an antibody of known reactivity; again the intent being to be sure the level of reactivity with your new lot is within acceptability to the reactivity of your old lot.

 

 

Question: What does my laboratory need to do to QC antibody panel cells when they are received?

 

Answer: Antibody panel cells are considered critical materials in a transfusion service. Laboratories must follow the requirements in TRM.312441 stating, “New lots of reagents and critical materials are inspected and tested, as applicable, before use, with documentation of acceptance”.

 

The inspection of the reagent involves a visual assessment to check for hemolysis or signs of contamination. The findings must be documented on a inventory log or other quality control record. Quality control of a new antibody panel presents a challenge because it is not feasible to check the reactivity of each antigen on each panel cell. In addition, antibody panels have a short expiration date and many laboratories order multiple panels to ensure that they have sufficient selected cells available for ruling out antibodies. An antibody panel is an investigational tool used to identify the specificity of red cell antibodies and is never used alone when interpreting the results. In addition, laboratories follow defined rules for confirming or ruling out antibodies on the panel, including comparing the results from the panel with the patient’s antigen typing for the antigen of interest, the antibody screening results, patient history, and additional special studies when indicated.

 

For quality control, the laboratory must follow procedures for interpreting the results and follow the manufacturer’s instructions for quality control, at minimum. While not ideal, the laboratory may also use the following processes to check the reactivity of the panel cells:

 

- Confirm the reactivity of one or more panel cell using a reagent antisera or a dilute antibody

 

- Select a known positive and known negative panel cell as the controls when performing an antigen typing

 

- Run a panel with a known antibody prior to use

 

 

- Since the red cell panel is an investigational tool to identify the specificity of red cell antibodies, labs can show that when they confirm the patient for the corresponding antigen and select a known positive and known negative panel cell as the controls, if the positive and negative cells react as they should, the lab would be satisfying this requirement.

 

I hope this helps.

Sincerely,

Kathy Passarelli

Technical Specialist, CAP

 

 

 

 

 

 

 

 

 

 

[Malcolm Needs ☆]

With due respect Phil (and I have a LOT of respect for you), that is not really doing lot to lot comparison.  It IS making certain that the new lot react with a weak antibody when they should, and not when they shouldn't (and, as I have said on this site loads of times, diluted antisera is not the same as weak antisera - whatever CAP may say!!!!!!!), but CAP are not saying that, say cell 1 of the new lot should react with exactly the same strength as cell 1 from the old lot, just that cell 1 of the new lot should or should not react with the weak antisera strongly enough so that a weak antibody would not be missed; on other words, they are saying the same as Anna.

[Dr. Pepper]

And I have the utmost respect for you as well. I'm also not disagreeing with you, Anna, or anyone, I guess it's just a point in semantics.

[DebbieL]

If we are getting different answers from CAP about the same thing, there is no hope for us all. We are doomed to total confusion if the experts can't agree.

I think if you call and you get a CAP person that is a Chemistry expert they would say you had to compare because that makes perfect sense to them. If you get a person that is a BB expert, they would know more about the nature of our work and reagents. The person I talked to even said that BB was different and our reagents were different. Our reagents are QC'd everyday of use. If it doesn't work, we don't use it. The person I talked to about this said we didn't have to compare reagents or antisera BUT we did have to compare "kits to kits" to show that the new kit gave comparible results as the old kit. I guess kits are different because there are several parts or steps that could fail to work correctly.

I am going to stick with comparing my kits (FMH and Elu-kit) and not comparing my regular and rare antisera until forced.

[Eagle Eye]

When we open a new reagents (excluding anti-sera), we run QC again with same QC material and document the result on same form. We divide column into two and document on same and document as parallel testing done and new lot is acceptable for use.

Most cases we end up doing this on day of expiration of the reagent.

To me it is not lot to lot comparison but you are testing your old lot and new lot against same material and making sure that new lot gives you acceptable result and if you decide to use old lot for the day, your QC is done...

For panel: it can be done periodically.

[tbostock]

For panels, it's important to follow the manufacturer's instructions.  We use Bio-Rad and Ortho panels and they both have different requirements.  I wrote an IQCP for panels since I am not performing QC each day of use. 

[Carrie Easley]

We were inspected at the end of February, and got cited.    I challenged stating:

We are contesting this citation. We do not believe that this checklist item pertains to Blood Bank reagents verified for purity and potency by the FDA.

In our facility, all screening cells, reverse typing cells, traditional typing sera, and MTS gel cards are QC’d daily with known, previously tested patient samples. All other reagents are typed each day of use with appropriate positive and negative controls. This will make evident any compromise of the reagent that took place during shipment. Since Blood Bank is not generating numbers (as in Hematology & Chemistry), but rather interpretations, the lot to lot comparison would have no added value.

My challenge was not accepted, and CAP's response was:

Lot to lot comparison is required for blood bank reagents. You can use your quality control if the quality control that was run on the old lot is the same lot number as what is being run on the new lot. Additionally, you have to have a policy to address this process and there needs to be documentation showing this was performed. Provide this documentation. Your challenge has been noted.

[Malcolm Needs ☆]

10 minutes ago, CarrieM said:

We were inspected at the end of February, and got cited.    I challenged stating:

We are contesting this citation. We do not believe that this checklist item pertains to Blood Bank reagents verified for purity and potency by the FDA.

In our facility, all screening cells, reverse typing cells, traditional typing sera, and MTS gel cards are QC’d daily with known, previously tested patient samples. All other reagents are typed each day of use with appropriate positive and negative controls. This will make evident any compromise of the reagent that took place during shipment. Since Blood Bank is not generating numbers (as in Hematology & Chemistry), but rather interpretations, the lot to lot comparison would have no added value.

My challenge was not accepted, and CAP's response was:

Lot to lot comparison is required for blood bank reagents. You can use your quality control if the quality control that was run on the old lot is the same lot number as what is being run on the new lot. Additionally, you have to have a policy to address this process and there needs to be documentation showing this was performed. Provide this documentation. Your challenge has been noted.

Hmph.  Sadly, with the QC bit, I can see from where they are coming - but harsh if the QC worked.

[Carrie Easley]

The QC always works...that's what was frustrating.  We did note on our response the mixed information that seems to be circulating from CAP regarding this topic.  Hopefully they can all get on the same page, and alleviate some confusion!

[Carrie Easley]

To add confusion...

Immucor audioconference 04/28 with CAP, AABB and TJC about competency, proficiency, QC and IQCP. There is a slide that states:

New Reagent Lot Confirmation of Acceptability

•COM.30450 New reagent lots and shipments are checked against old reagent lots or with suitable reference material before or concurrently being placed in service

–Daily QC of ABO, Rh, Antibody Screen satisfy the intent of the checklist item provided acceptance criteria are defined and outcome of results are recorded

–May not apply to panel cells (see TRM.31241)

–Does apply to kits (such as fetal maternal screen test kits)

[DebbieL]

I also listened to the Immucor webinar. What I got out of it was BB does not have to do lot to lot for our reagents, rare or otherwise. We do daily QC and the reagents must pass before use. We do have to compare current FMH kits to incoming FMH kits. You must make sure the controls on the current kit work on the new kit and vise-versa. This is to make sure the controls on the new kit work as expected and that the shipping conditions did not cause the cells to deteriorate. We had also been comparing Elu-Kits but someone specifically asked if those needed to be compared and they do not. I think I heard that it is because there are not any controls in the kit. I am grateful for small favors so I am getting rid of the Elu-kit comparison portion of my procedure.

When it comes to comparison of panel cells, look carefully at the package insert instructions. Does it say you HAVE to QC? Then you must. Does it say you MAY test, then it is up to the facility if testing is done. I personnally take that as a legal loop-hole and will run with it. Besides how could you ever compare one panel to another since you would be comparing different donors?

I had talked to CAP in the past about this subject. They said you must check all incoming shipments for proper shipping conditions AND must be checked prior to use and these checks must be documented. I made up a form that reagents are listed as they come in (date arrived, #, lot number,etc.) and I added a column for checking the shipping container. Acceptable Yes or No. At the bottom of the page in small writing I listed what was acceptable and what was not so there was not question.  All of this checking must be documented. We all know if it is not written down, it hasn't been done.

Below is the next slide from the Immucor presentation:

TRM.31241 All new lots of reagents and critical materials (e.g. blood collection sets) are inspected and tested, as applicable, before use with records of acceptance.

- If manufacturer’s instructions require testing prior to use (e.g. panel cells, antisera) then lab is expected to test

-If manufacturer’s instructions recommend testing prior to use, it is up to the discretion of the laboratory to test

-Once reagents are put into use, TRM.31400 applies