Leaderboard

If you put a drop of blood on something like a filter paper, and then add a drop of 1M NaOH, if it is adult blood, after a couple of minutes it will turn a sort of yellow/brown colour, as the Hb is denatured by the alkaline, whereas, if it is blood derived from the baby (including cord blood), the red cells will stay red, as HbF is not denatured by the alkaline for much longer. It is rather like doing a Kleihauer, but by "bucket chemistry", as it is known!

For those of who works in transfusion service laboratory and would like to learn more reference cases, I can post some mock-up cases here. If you would like me to do it, please hit the "heart" button on this post. If enough folks want to practice case studies on reference lab cases, I can post mock-up cases here weekly or so..

My advise for safe patient care is confirmation of the patient blood type by a laboratory professional.

LOL! We would send it to our reference lab! We have other things to do here... Scott

Agree with AMcCord. Can't and don't want to imagine nursing personnel performing this test.

I certainly wouldn't use your nomenclature (only genes can be homozygous, heterozygous or hemizygous), but I know what you mean. I would most certainly say that the patient's plasma contains an anti-M, but, despite the fact that many cases of "cold reacting" anti-M are IgG, if the anti-M does not react at strictly 37oC, it is not clinically significant.

We just got our first anti-CD47 out here in the sticks on a patient who went to Seattle for a clinical trial. That drug is Hu5F9-G4. No other name yet. It interfered with her reverse as well as all gel testing. We did a 30 minute saline screen and it was 4+ at 37C but negative at IAT using Immucor's anti-IgG which doesn't react with IgG4. She was antigen typed before starting treatment so we got that information and gave her K and Fya negative units (lucky she is positive for most antigens). We called them incompatible because we have not validated the Immucor anti-IgG as our test of record, the screen was 4+ at 37C and because the drug causes the patient's H&H to drop so I wasn't sure that the units would be certain to have normal survival. I didn't expect to get one of these for a few more years since we aren't in a big teaching hospital region. It would have been nice if the big center had sent her home with information that she was on this and instructions to tell the blood bank. We lucked out finding clues in Epic's Care Everywhere so we called the Seattle blood bank.

Most transfusion practices in neonatalogy, including this one, are not evidence based, but rather empirical expert opinion. The use of reconstituted whole blood is more historical than anything else. A unit or two of recently collected (perhaps 7-14 days) whole blood would probably be as rational. One might check the potassium before using to make sure it isn't super high. That is the rationale for washing a red cell. It removes potassium from hemolysis during collection and storage, and makes the red cells more likely to absorb potassium once transfused. It's definitely more useful if the baby is hyperkalemic to begin with. Otherwise, whole blood would be fine. The reason for using plasma is fear of hypocoagulability, which is probably mostly mumbo jumbo for small exchanges, but might be more of an issue for larger exchanges (2 or more blood volumes). There is no real proof that any of these approaches is superior or inferior. Calculating the hematocrit is a case of weighing the red cells and measuring their hematocrit and then diluting accordingly with plasma or albumin solution (5%). You don't want a hematocrit higher than 40 in the exchange as normal neonates do not have high hematocrits and oxygen delivery is actually worse at hematocrits much above 30 in experimental models. In this case, more is not better as far as anyone knows. Once again, this is expert opinion not evidence based.

Our experience w/ bedside testing for glucose at bedside and for stool occult blood card tests by nursing staff demonstrates that they don't understand QC, don't understand that if things don't look right you don't report it, don't document what they should document, etc. The thought of letting them perform confirmatory blood types for transfusion therefore scares the living daylights out of me. You can train some to perform the steps reliably, but without the lab background, I don't think you can expect good performance in dealing with unexpected results and test system problems (QC failure, weak/missing reactions, discrepant results). Those are the things that can result in a hemolytic transfusion reaction.

I find a considerable number of anti-M's using gel. The majority only react w MM cells. Gel is known to enhance anti-M activity (at least Ortho's). When I find any anti-M I set up prewarmed testing to see if it is clinically significant. Usually these types are not.

If the patient has been transfused or pregnant in the last 3 mos, one has to r/i r/o significant atypical antibodies every three days. This going to involve more than a screen. Scott

Without a doubt, we would follow your method srichar3, otherwise, what is the point of performing a reverse group on ANY sample?

I'm pretty sure any of the commercial QC systems will have this covered and I don't remember them being all that expensive. I have used both the Ortho and Immucor systems and don't remember any issues.

ORTHO CONFIDENCE

We do this test on all Rh (weak D) negative cord blood specimens from babies with Rh negative moms -- just to make sure that it is baby blood and that mom doesn't need RhIG.

Works well when someone brings you a 'red' diaper or burp rag and wants to know if you can do a blood type to see if the blood is mom's or baby's. (Doesn't work worth a darn though for cherry/red colored meds or drinks )

Could be maternal blood. Have tried testing the red cells with NaOH?

Nurses performing ABO/Rh testing, scary. AMcCord and R1R2.

Gosh, one would hope so!

When leukodepletion first became "popular" in the UK, before the NHSBT and other Blood Services performed universal leukodepletion, we used to provide the ward with an "in-line" filter. As Ensis01 says above, there were several drawbacks with this, but, in terms of whether it was actually efficacious, it was marginal then, because part of the problem involved with febrile non-haemolytic transfusion reactions (this is a problem separate from the fact that we want to prevent "HLA" type sensitisation) is the release of such things as cytokines, in particular tumour/tissue necrosis factor-alpha, interleukin-1-alpha, interleukin-1-beta and interleukin-6. These are released from white cells upon storage and, of course, by the time the platelet concentrates reach the hospital blood bank, these will already have been released, and so it is too late, and leukodepletion will not prevent FNHTR.

We do see cold anti-Ms (or colds that mimic anti-M) causing trouble with gel often enough -- they have to be resolved in tube, often with the pre-warming, We are unlikely to do any further testing to identify what kind of cold antibody this is. Its just unusual to get a patient with a strong cold agglutinin that does not interfere with our manual gel screen testing. We are not complaining! The patient has been transfused a few times with no problems. Scott

This is not a popular concept but at some point we have to accept there are things we can not control. Once the blood leaves the blood bank we are at the mercy of other humans and as long as the human factor is involved there will be human error be it unintentional or intentional. Attempting to complicate a process will only provide inventive humans the opportunity of coming up with creative work arounds to circumvent your best of intentions. At some point you just have to step back, do your job and hope for the best. I had a corporate transfusion QA director who could not accept that human error could not be completely eliminated with out eliminating human involvement in the process. Her directives became horribly complex solutions with multiple, redundant checks and balances only resulting in increasing problems. Bottom line, pick your battles and fight those you have a reasonable chance of winning. Make suggestions, offer insight, provide training opportunities but at the end of the day realize that you have to accept some things are simply beyond your control and even your influence. On that happy note I'll step off my soap box and stop my philosophical ramblings.

By definition, reagent reverse grouping A1 and B cells are used to detect anti-A and anti-B antibody in patient plasma. Accordingly A1 cells should react with anti-A but not with anti-B, and B cells should react with anti-B but react with anti-A. Therefore, A1 cells should not be agglutinated by anti-B. No agglutination is a negative test result, i.e., a negative control test. Likewise, B cells should not be agglutinated by anti-A. No agglutination is a negative test result, i.e. a negative control test. Testing A1and B cells with AB plasma, Diluent, Albumin or saline may demonstrate that the test cells are not spontaneously agglutinating in their presence which serves as a negative control for those reagents, but does not serve as a negative control test for A1 cells or B cells.

Hi Maryann, The point is that the terms homozygous, heterozygous and hemizygous can only refer to genes, but, of course, red cells do not have a nucleus (it has been extruded during the maturation process), but, in any case, the terms should not be used for antigens. In this case the closest to being correct is that M+N- red cells have "homozygous expression" and M+N+ red cells have "heterozygous expression". However, particularly in the case of the MNS Blood Group System, this terminology is not completely correct. There are many low prevalence antigens associated with both the glycophorin A and the glycophorin B molecules, and the many hybrids therein, that a red cell that groups as M+N- may not be as a result of MM homozygosity at a genetic level, but may have heterozygous expression, because there is one "M" antigen (for want of a better way of putting it), and one low prevalence antigen expressed on glycophorin A (or a hybrid), so that, in terms of expression, the M antigen has the strength of an M+N+ red cell, rather than an M+N- red cell. I hope that helps. Malcolm

I keep a notebook with calibration certificates in it. I also have a reminder on my on line calendar that comes up about 4 weeks before the calibration on that item expires. When I see the reminder(s), I order new thermometers. Ditto for the stop watch. Those things are not big budget items. Once they come, new thermometers go into service, old ones are removed and discarded, new certificate goes in notebook, old certificate goes into archive file. I decided a couple of years ago that I am too hard pressed for time to check calibrations on things like thermometers. Biomed has put my scale (for the Echo) and the tachometer on the list of things that their outside contractor checks yearly. My pipettes get sent out for calibration check - one of our evening techs is responsible for that, so all I have to do is check the certificate and file it in my notebook. When the inspector wants to see that stuff, it's all in one place. Prior to this, I had a simple spreadsheet with all of the thermometers on it, listed by serial number. Each year I used a fresh copy of it. Part of the thermometer ID was where it was at. If it got moved, I changed that info on the spreadsheet, so at least I could find them. If they failed the annual check, I would note that and indicate that they were removed from service on that document. Once removed from service, that one was removed from the spreadsheet and the replacement was added. Those went into my notebook. I make a note at the top of each item's calibration certificate the date it is placed into service and the date it is removed from service. I don't have a huge number of these types of things, so it works for me. If I had more, I think I'd add a 'permanent' spreadsheet for tracking everything that documented in service date, removal from service date, and anything else that seemed important - just adding new lines for new stuff to the bottom of the ever growing list. I'm trying to put as much of those kinds of documents as I can into MediaLab to make review/approval documentation easier.

Could someone re-post the link to the NYCBC poster? It looks like the link on these posts is no longer valid.

In my opinion, if we cannot select an antigen neg reverse cells, there are things we can do, it is adsorbing the plasma/serum using pooled O cells, then do the reverse typing, to get a neat anti-A or anti-B result.

I don't think you can do much "assuming" like this in the BB, much less healthcare in general. A unexpected positive reverse cell is most likely due to something innocuous, but it could be, at the least, a sign of an ABO subgroup or whatever. In any case, you would want it all documented for the next time you see that patient. Scott

Anti-A for the group B red cells and anti-B for the A1 red cells.

Best patient safety care..DO NOT ALLOW NURSING TO DO THIS!

I wouldn't trust a nurse in performing ABORH testing, they have a hard enough time with other point of care tests.

A very bad option. Look at it this way. You probably could not do their job. They cannot do ours - and ABO matching is THE single most important in transfusion. Most ABO types are, I agree, pretty easy, but some are most definitely not. For example, could a nurse tell the difference between a group O and an Oh? I have huge doubts.

So is having nurses "confirm" the ABO type at the bedside; believe me!

If by "odd antigen" you mean a low incidence/frequency antigen on that specific A1 cell/donor, it should be easy to resolve using another A1 cell (or set of Reverse Cells) - the forward and reverse would compliment each other. However, if everyone is having problems with this patient, it's unlikely to be the reverse cell(s). Is the GI bleed due to ulcers ? H. pylori, perhaps. I think I read that some folks with H. pylori make cold autoantibodies.

I suggest you contact other facilities in your area and see what they have been doing. You will want to know how they are satisfying any regulatory requirements with whatever method they use. Scott

As ABO typing is so important I think you will have difficulty justifying to your regulatory bodies this test done at the bedside by nursing professionals. Who or which department are you researching this for?

I don't know what happened, but I tried to answer three times on here, and each time it locked up, so Dansket, I have written a Word document in reply, and attach it should you want to read it. PathLabTalk Answer.docx

So the A1 cells are reactive, but the O cells are nonreactive. Interesting. I would have guessed autoanti-H, but that doesn't fit. Have you tested A2 cells ? Might be a weird compound antibody like anti-HI - needs the presence of both antigens to react well. Have you looked at something simpler, like anti-M, for instance ? The DAT results suggest IgM/complement binding, but as you imply, further testing is required.

I think that this would very much depend upon whether the red cells are from a donor or a recipient. In the UK, for example, the anti-D reagents used in hospital laboratories, where they are testing (almost exclusively) patients, are designed not to detect Partial DVI, whereas those used in the NHSBT for donors and, to a certain extent, some of the reagents used in the Reference Laboratories are designed specifically to detect Partial DVI. This means that an individual could be designated as D Positive as a donor, and D Negative as a recipient. This would take a bit of explaining to the individual involved and, very often, to the doctor looking after the individual if they were not too familiar with transfusion. I would be amazed if manufacturers would make such a direction, because it is unlikely that all anti-D reagents are guaranteed to detect ALL partial D types (notably the DEL types) but WILL detect ALL Partial DIII type individuals, which can, and often do produce an allo-anti-D. I would be very confident to defend my own policy to a knowledgeable inspector, although I HOPE such an inspector would be knowledgeable enough NOT to ask about this in the first place! The attached diagram is of Partial DVI Type 1 (copied from a diagram by Geoff Daniels). Partial DVI Type 1.pptx

Sorry, but can I just point out that you should be sending out the tests if the patient is a female of child bearing POTENTIAL, rather than child bearing age. If the female is four (for example), she is not likely to be of child bearing age, but she will be one day, and if she is an individual who has a Partial D type who can produce an anti-D, she deserves as much care as does a female of, for example, 25 years.

There are three types of people. About 10 - 15% are non-responders, and never produce an antibody, however many times their immune system is challenged. About another 70 - 80% are normal responders and, given sufficient stimulus, will produce antibodies. The other 10 - 15% are super responders, and produce antibodies with the slightest insult to their immune system. I once heard the wonderful Dr Ed Synder describe these people as being able to produce an anti-D after being given a "virtual transfusion". When questioned as to what was a "virtual transfusion", he said that you showed a photograph of a D Positive red cell to such a person, and they produce an anti-D!!!! I would suggest, Kathyang, that your mother was an extreme member of the first group.

I totally agree with David. I would say most of our Anti-M's react only with the cells that have the homozygous expression and not with the heterozygous expression. I would say you have to call it an Anti-M especially if Gel is your primary method of testing with tube as your backup. I don't think you can call it negative just because the tube has no reactivity. We sometimes (very rarely) would have a Warm autoantibody that showed pan-agglutination in Gel but was negative with tube method at one hour incubation, no enhancement excluding the auto control which is usually still reactive. We would just add a comment about the negative results in tube method just for proper documentation but still result as a Warm autoantibody.

All the DTT treated cells were still positive so that should rule out Darazalex. I wonder about the new one anti-CD47? Has anyone run into it yet and do we have any way of coping with it yet? Does it have a name yet? I was thinking anti-Fy3 or anti-U because of the ficin testing results, but the phenotyping is wrong for that, isn't it?

As per CAP standards TRM.30575 Misidentification risk: Verify ABO/Rh on second sample prior to transfusion and TRM.40670 ABO Group and Rh(D) type verification, we order a non-billable TYPE2/WEAKD and result to meet the requirement for electronic crossmatch and/or type specific blood to be issued on a patient with no historical data. This a new order/draw.. specimen must have blood bank id documented on tube by collector at time of collection in the presence of patient. if a second sample cannot be obtained and there is no documented previous ABO/Rh, immediate spin crossmatch performed using non type specific blood. if the phlebotomist is still on duty and has a clear recollection of patient they may be allowed to take tubes from earlier draw to patients bedside to re-identify patient and sample, placing blood bank id sticker on that tube. we usually use CBC tube from am draw. anytime a type and screen ordered on hosp patient the phleb asks the bb tech if a prev type exists if not a type2 is ordered on new order number requiring second venipuncture. are your bedside test cards properly labeled date/time/init blood bank id, patient LIS label /order label to compare to patient wristband? are the results entered into patient chart?

We use saline just to make sure they aren't just agglutinating.

Yikes! I would hope that your facility's patient and specimen ID policies have improved since those days! Scott

JoyG This happened over 20 years ago. I would imagine things have changed since then and to be honest I never did hear if the insurance company paid for it or not. Was just using it as an example. You didn't answer my question, does your billing indicate that these charges are specifically for testing in regards to a potential transfusion reaction?

In that case, I would have wanted to see the reaction with that one cell in panel A for myself. There is most certainly a difference between genuine weak agglutination, and a couple of red cells "getting to know one another". IF someone with real experience says it is the latter, I would be happy to go to either "immediate spin" or electronic issue.

or it might have been anti-buffer or cold 'rubbish'......

That came up at an AABB session I attended last year. Policies seemed to range from 1-2 units up to 6-8 units of incompatible plasma. Some policies specified a time frame as well as number of units - X number of ABO incompatible units over X number of hours. I was hoping to hear some kind of concensus, but there didn't seem to be one from the comments I heard. Do your research, draw a line in the sand for what you think is reasonable, and write your policy accordingly. Since the standard does not spell out what reasonable is, you get to decide.