Ortho Gel new prediluted cells formulation

[Mabel Adams]

Is anyone finding any differences with the new formulation of Ortho's pre-diluted 0.8% screening and panel cells?

[lef5501]

We have tested 4 samples so far with the new gel cells and no differences yet. I just wish I had a really weak Anti-E to test since that seemed to cause the biggest problems with the old cells.

[bbbirder]

So far we have tested about a dozen with no differences found.

We have one patient I wish I could evaluate with the new cells because he has a very weak anti-E. Alas! he also has anti-c and we don't have any Rz's in the new cells.

[Mabel Adams]

I ran about 3 cold agglutinins (one is known to be anti-I) and found that one did not show up in either lot, one showed up in the old lot but not the new and one was opposite. All the "normal" antibodies that I ran had the same results in both. My eluate, last wash, warm auto and adsorbed serum all reacted the same in both.

[jhaig]

I recently finished some correlation studies and found no real significant differences. The new cells showed some slightly stronger reaction strength (3+ vs. 2+) on some patient samples of Anti-K and Anti-M and there were some weaker reactions seen with a couple of Anti-E patients (1+ vs. 2+). Some of the patients I used had been aliquotted and frozen so some of the variability may have been due to the plasma being frozen, but I have no way to tell. On the fresh patient specimens I used (approx. 25 specimens) there was virtually no difference. I have yet to do any eluates, but as far as antibody screening and antibody ID, the new Ortho cells worked just fine.

:cool:

[Cathy]

I had a patient with a previous Kell, now non-reactive. One of the K-neg units came up 1+ incompatible in gel. So I rechecked the antigen screen, it was fine. Gel Panel A was all negative so I decided to look for some low frequency antibodies. He was also transfused 6 weeks ago so I set up a liss screen and found that the K reacted. I ran three positive K cells with the newly formulated cells in gel, only one reacted and it was very weak

[janet]

I found one previous Anti-K that was no longer reacting came up weak with 2 of the 3 K+ cells in the new formula.

A couple antibodies appeared a bit stronger (2+ to 3+) for me also.

A weak unidentified was 2+ in the new formula but still had no pattern

How many comparisons are you perfoming?

[lef5501]

We just had a previous Anti-E and Anti-K come in today. His screen was 1+ pos with both the old and new cells. The panel was negative(twice) when we ran the old formula panel, but with the new panel cells, both the E and K came up 1+. Not much difference with the screening cells, but it did make a difference with our panel results.

[jlw]

We had a patient who was forming an anti-Jka from a March transfusion who tested negative with the new-reformulated screen cells on May 1 and was luckily not transfused. The patient was retested a week later and the screen cells were weakly positive. When the May 1 sample was investigated, the anti-Jka reacted 2+ with the old black cap screen cells and weak pos or negative, depending on incubation times, with the new formula of screen cells.

This is the opposite of most of the testing we have performed. We have done 45 positive screens, 48 negative screens and 45 antibody panels in parallel.

Additional info gained this weekend on subsequent testing. anti-Jka was not able to be detected until 5/8. Reactivity on 5/1 actually was anti-Cw so our concern is abaited.

[Mabel Adams]

We had one patient that I suspect made antibody to a gel diluent constituent. It appeared to be significantly weaker with the new formulation. Ortho's notice said they used lower doses of antibiotics in it, so maybe that is why.

[Shari]

We tested our samples, and found no difference bewtween the old formula and the new formula.

[RWOOD57]

We have found 6 patients with Anti-M (demonstrating dosage) in the past 2 weeks with the new formula. I have no hair left! Anyone else having these problems?

[marilynm]

Just a comment, since it was said I had not been on a while. Anytime you use different methods and change the formulation of any products, you should not expect to always get the same answers, or even the ones you would like. The old saying "the antibodies do not read the books" is still good today. marilynm

[Trek Tech]

During verifcation with the first set they sent we had one of our sickle cell patient's anti-E come up 1+ in the new formulation and negative in the old. He had not been demonstrating for about a year. We have had another patient's anti-K demonstrate again in the new formula! We have seen a difference!

[Mabel Adams]

I see lots of anti-Ms in gel regardless of the formulation.

[Eagle Eye]

we noticed more anti-M (sometime reacting with only homozygous cells) and lewis also. on three cases we had cells 1 positive and panel negative but when we used panel C--identified anti-Lea.

[Mabel Adams]

Is anyone else having problems with false positive reactions in prediluted screening cells now? Our first ordered lot of the new formulation (not the correlation lot) seemed to be one of those occasional lots with a stronger Sda expression or something. All cell 2 vials from the lot reacted the same way. The two lots since then have each had weak reactions mostly in cell 2 on some patients, but when we pull a new vial of the same lot out and run it, we get negative. I am wondering if the cells are deteriorating in some way that they didn't before.

[OPUS104]

Yes Mabel we have seen an increase in "non-specific" reactivity. (mainly cell 11).....we have chased these reactions fruitlessly. PEG, Ficin, every enzyme treatment we do,converted rare cells, dilution studies in desperation, DAT tested reagent cells.... we are tired of reporting Anti-(fill in the blank) and other unidentifiable reactivity. We have even sent a couple of these to MAJOR reference labs (we are a small ref. lab) with no luck. Please shout out any help.

[Eagle Eye]

We had a patient this week with screening cell II reacting 1+, Panle A was negative. We usually do not do additional workup but repeated Screening ----still positive. We ran panel C ....clear anti-K???

[Mabel Adams]

Maybe it is our panel A that is deteriorating! But that wouldn't explain why the new vials of screen cell 2 come up negative with the same sample.

We tend to leave our reagents out on the counter most of the time and only go through about 2.5 vials per month. Maybe we should be popping them in the fridge more???

[Gerald]

How are dealing with the false positives? I don't want to have to get out a new set of cells every time I get a pos screen.

We had 4 false pos reactions on cell 2 on our previous lot. Pos absc cell 2 and negative in the panel.

Now just this morning I got a positive in cell 1 that repeated neg with a new bottle of cells of our current lot number.

[Brad D. Ross]

We have had nothing but trouble since the new screening cells have come out for Gel. It seems that we are getting false positive results all over the place. Upon further investigation, it appears to be due to the fact that Ortho reduced the antibiotic in the cells by six fold. Since we are a fairly large hospital, and leave our screening cells out all day, this decrease appears to have caused this effect. Now we have to make aliquots each day, and place them out. At the end of the day we throw away any extra, and get out new the following day. What a PAIN!

[OPUS104]

We have been discussing getting rid of the pre-dil screen cells and using our 3% 3 cell screen instead........convert enough for each day and throw away whats left at the end of the day. We get better results on weak reactions using converted cells anyway.

[Gerald]

We have a Provue so the cell management becomes a lot harder because it reads the barcode on the reagent bottle. Anyone running a Provue having these issues and how are you handling it?

Thanks

[babsglab]

I did have a patient with a very weak Anti-E which was picked up with the new Ortho screening cells but not with the old cells.