Spurious reactions on the ECHO.

[sniedz]

Can anyone tell me what they do when they suspect a patient is reacting to the ECHO method? Ex. a patient is reacting to all panel cells on the ECHO, DAT is negative, and patient is giving negative screens using PEG and LISS. I haven't wrote a procedure yet on how to handle this. I contacted Immucor and they said each lab has to decide on how to handle situations like this. I tell the techs if a patient is all positive on the ECHO, DAT negative, and the screen cells were negative using bothe PEG and LISS, we can assume they patient is reacting with the ECHO. We turn out "Clinically significant antibodies ruled out" and I tell them to still do an extend crossmatch. (Part of me still worries they could of had an antibody we didn't know about and thetiter is too low or they could be developing a new antibody.) Any help is greatly appreciated.

Shelly

[Generic]

I don't have any experience with the ECHO, however occasionally something similar happens with the Provue. Depending on the reaction, it'll either be an antibody against a preservative in the 0.8% cells or an antibody against something in the gel cards. We repeat the original screen in the tube or using 3% cells diluted to 0.8%, depending on the situation. If the repeated screen comes back negative, we result the antibody as an unidentified, with a comment saying something along the lines of "probable antibody to preservative in 0.8% cells" or "probable antibody to gel - perform all testing in tube." In these cases we'll perform all crossmatches through AHG.

[Malcolm Needs ☆]

I would thoroughly concur with Generic's post.

[JOANBALONE]

We do the same as Generic.

JB

[estiner]

To confirm the reactions could be due to interference with solid phase technology, we perform a major crossmatch with patient sera and unit - since there is no stroma in the well for crossmatches, any interference would not occur - so if crossmatch is compatible on the ECHO, screen is negative in LISS, then we report suspected interference.

[macarton]

We see this type of reaction frequently with the Echo. We repeat the screen by gel and report the reaction we get with it and do workups by gel if indicated.

[OxyApos]

We occasionally have these on the Echo. At first I sent these to our ARC reference lab assuming they were warm autos. On their advice, I now perform a DAT, tube screen with LISS and a major crossmatch. If these are all negative, I call it a negative screen and move on. No one has had any sort of reaction. I have also had the rare cold, Sda, and Lewis react on the Echo like this. Some patients who have fresh chemo treatments and then come in for transfusions have had these reactions too.

[AMcCord]

We occasionally have these on the Echo. At first I sent these to our ARC reference lab assuming they were warm autos. On their advice, I now perform a DAT, tube screen with LISS and a major crossmatch. If these are all negative, I call it a negative screen and move on. No one has had any sort of reaction. I have also had the rare cold, Sda, and Lewis react on the Echo like this. Some patients who have fresh chemo treatments and then come in for transfusions have had these reactions too.

I do the same, though we routinely use PeG rather than LISS. Our internal patient record says "solid phase reactive antibody of undetermined specificity - antibody screen negative with PeG", so that the next time we see that patient we know what to expect (or not! - sometimes the problem disappears with changes in patient condition).

[OxyApos]

Yes we do place an internal comment in our computer system for future warnings. Most of our docs wouldn't know a non ID from any other antibody so we don't bother if we've resolved the problem and crossmatches aren't a problem. I've also had an occasional lot number on the solid phase/ Echo strips that had patients who were septic give these reactions. Once the septicemia was resolved, the reactions went away. Blood Bankers still have to think. Automation doesn't give all the answers.

[L106]

I do the same, though we routinely use PeG rather than LISS. Our internal patient record says "solid phase reactive antibody of undetermined specificity - antibody screen negative with PeG", so that the next time we see that patient we know what to expect (or not! - sometimes the problem disappears with changes in patient condition).

We do the same.

Donna

[Malcolm Needs ☆]

Blood Bankers still have to think. Automation doesn't give all the answers.

TRUE, TRUE.

Now convince the upper level of management!!!!!!!!!!!!

:angered::angered:

[SPL1115]

Usually all positive reactions on the ECHO and negative in PeG & LISS are due to a warm auto or drugs. We place a canned text comment on the patients specimen that states, " PeG antibody screen negative, no antibody identified." We follow up with a complete crossmatch. It can also be resolved using the Manual ECHO workstation. We pre-heat the antibody screen strips (Capture RS-3) in the incubator for 20 min., that will also resolve the problem.

[L106]

We pre-heat the antibody screen strips (Capture RS-3) in the incubator for 20 min., that will also resolve the problem.

That's interesting. Would I be correct that pre-heating the strips in the incubator for 20 minutes is not included in the manufacturer's directions? If that is true, how do you get around deviating from the manufacturer's directions? (Did you do some type of validation, etc?)

Donna

[SPL1115]

Pre-heating the strips in the incubator for 20 minutes is not included in the manufacturer's directions, however, we got around that by doing an In-house validation of our own with strong and weak cold reactions that also gave us negative reactions with PeG. We re-correlate these reactions 2 times a year using a prewarmed techinque in GEL Cards, PeG, and the pre-warmed Echo strips. We use 12-20 specimens for the correlation.

[Tony R]

We do basically what most people do we just repeat the screen with the tube technique using Peg and Lis to AHG, if they are both negative we report it out as negative. If either is positive we do a panel using which ever enhancement media gave the (+) reaction. Just an FYI I did some limited studies on patients who tested 4+ everywhere on the echo. I did a Direct coombs and if that was negative I would take an auto control and two screening cells to 4 C for approximately 30 min. and almost always I found a cold auto antibody. I realize that if you took most specimens to 4C you would run the risk of finding a cold but like the rest of you blood bankers tend to want a reason.

later

Tony

[macarton]

The 4+ reactions on all screening cells seem to be more prominant since an update a few months back. One of the selling points used by the sales rep was that it didn't pick up colds. Like Tony, we've checked some of those with a negative gel at 4 degree and are finding colds. Mary

[L106]

Yes....through our 4 years with the Echo we find that in most patients known to have Cold Auto-Antibodies show completely Negative Antibody Screens on the Echo. However, some patients with Cold Auto-Antibodies do show a Positive Antibody Screen when tested on the Echo.

Donna