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God is Great, Beer is Good, Some Regulations are Crazy... Why not use outdated sera and cells for screening and then use the 1 in-date bottle to retest and use as test of record? What about rare red cells and sera from commercial or patients that may be frozen in liquid nitrogen and used to help with antigen and antibody problems? Of course you would run controls. Where have all the blood bankers gone? Who is writing these regs.? Have they been out of the lab too long? There are patients waiting for us and our results..... I will step off my soapbox now. Good Luck to all and to all Good Luck.

Ok, and the winner from molecular testing is......cis AB! (which was proposed by Monique). I remember learning about that in Med Tech. training 30+ years ago....but can honestly say I have never come across it (so while it may have been my "thought" when I was a new Tech. (mainly because I hadn't seen or heard of much more than that), I have seen so many strange things since then that your mind kind of looks for the bizarre). Also in my years, while I have seen plenty of strange and/or complex antibody issues, I have to say, I have not seen "all that many" complex Blood Types. So very interesting for me! Thanks again for all of your input, Brenda Hutson

Sometimes I think that the "regulators" feel obliged to fix problems that don't exist. Does anyone recall a rash of patient morbidity/mortality due to the use of expired reagents in the blood bank arena? That being said, the use of such material should be restricted to those with the appropriate knowledge and expertise.

To say we are having problems is an understatement. This seems to only be an issue for Vision users; the camera is very sensitive and is picking up weak reactivity that the instrument is calling "?" reactions. Because the image is enlarged on the Vision screen, you can actually see specks in the column on reactions that should be negative (including negative QC). Multiple reports have been filed, and we have gone through about half a dozen IgG card lots. We are beginning to see these in our manual testing now as well (although you have to look VERY closely). It appears that the problem is something that changed with the gel card production, although nothing official has been released by Ortho yet. Older lots of IgG cards are fine, which proves that it is the gel cards. Hopefully this is resolved soon...

Hi Scott, I'm back in the land of the living! I think the key bit of your quote from the Technical Manual is: "However. an eluate from the patient's red cells coated only with complement should be tested if there is clinical evidence of antibody-mediated hemolysis, for example, after transfusion. The eluate preparation can concentrate small amounts of IgG that may not be detectable in routine testing of the patient's plasma.". which, incidentally, is essentially what I said in an earlier post. The other important phrase from the quote from the Technical Manual is: "When the only coating protein is complement, the eluate is likely to be nonreactive." The word "likely" is very important here, as it means that the eluate is not definitely going to be nonreactive. Particularly in the case of a very weak antibody, such as one that is derived from an anamnestic response, it is not unknown for almost all of the said antibody to be sensitizing the red cells, and for very little, if any, of this antibody to be free in the plasma/serum - certainly not by normal serological techniques. However, if an eluate is performed, and the eluate is made with less eluting fluid than normal (normally it is a 1:1 ratio with the washed packed red cells, but that ratio can be changed to, for example, two volumes of washed packed red cells to one volume of eluting fluid), then essentially, the concentration of the antibody being eluted from the red cells is doubled. Such findings were described in Sachs UJH, Roder L, Santoso S, Bein G. Does a negative direct antiglobulin test exclude warm autoimmune haemolytic anaemia? A prospective study of 504 cases. British Journal of Haematology 2006; 132: 651-661. As I have said in other, earlier threads, although this paper was designed to look at DAT Negative cases of AIHA, the authors also actually describe many cases of a delayed haemolytic transfusion reaction (possibly delayed sereological transfusion reactions) detected by eluting antibodies from the red cells of the patient, even though the DAT was negative and there was no free antibody in the plasma/serum that was detected by routine serological techniques. So, the evidence from this is that the eluate may well be more reactive that the plasma/serum in terms of being able to identify the presence of, and elucidation of the actual antibody specificity. You go on to say: "And this from Malcolm: there are times when the causative antibody is an IgM. But what is the likelihood that you are going to pick up an IgM antibody (significant or otherwise) with the anti-IgG reagents used for antibody detection? And from an eluate no less, which I believe are notoriously weak anyway even if present?" What I was driving at here was the fact that, if there is clinical evidence of antibody-mediated haemolysis, particularly after a transfusion, every effort should be made to identify the specificity of the antibody, to ensure that the cognate antigen is not expressed on the red cells of any units that may subsequently be transfused. This effort may include the use of a clotted sample, rather than a sample anticoagulated with EDTA, as, of course, the EDTA would chelate the calcium, manganese and magnesium ions that are required for maximal initiation of the classical complement cascade. In such a case, a monospecific anti-C3d reagent, or even a monospecific anti-IgM reagent, rather than a monospecific anti-IgG reagent would be used. It was in this way that one of the red cell immunohaematology reference laboratories of the NHSBT was able to show the presence of an IgM anti-Vel in the circulation of a patient who had undergone an acute (sadly fatal) haemolytic transfusion reaction, where no IgG anti-Vel could be detected in the plasma. The bit about the "strength" of the eluate I have dealt with above. I am acutely aware that the ability for the normal hospital blood transfusion laboratory to be able to carry out such tests is unlikely, as they would not carry the necessary rare and expensive reagents, but in a case where there is clinical evidence of antibody-mediated haemolysis, samples should be sent to a reference laboratory for full investigation before further transfusion is attempted, unless the physician decides that withholding further transfusion is more dangerous than a possible further transfusion reaction. Sorry for the over-long post.