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Was wondering how gel users are handling DATs. Since there is no anti-C3 card are you simply repeating all polyspecific positives by a tube method or as one individual suggested assuming that a positive poly and a negative anti-IgG was a positive anti-C3? Another issue is that I have heard reports that a positive DAT by gel does not always correlate with a positive tube test. How are you handling this? Default to tube method? Thanks!

Shily, Try to get some information on T, Tn & Tk activation of red cells from whatever technical resources you have. You should try to get access to the AABB Technical manual which will give you a good overview of these type of problems. Have a good day!

Does anyone have an experience with weak D-positive specimens run on the Provue? From the information that I've been able to gather it appears that the Provue is picking up at least some specimens previously typed as "Rh-positive, weak D" as simply "Rh-positive". Obviously there will be some that fall through the cracks. Thanks!

Shily, If your reference to "blood poisoning" is meant to mean that he has a bacterial infection I would suspect that this could be the source of the problem. Bacterial enzymes can certainly have an effect on red cell antigens.

----------------------------------------------- The OBs generally do what ACOG recommends. Basically when the Coombs titer is = or > than 16 "amniocentesis should be considered". In the AABB's "Guidelines For Prenatal and Perinatal Immunohematology" there are some comments related to FyA and Kell antibody titration significance that differ from the standard anti-D but I doubt whether many OBs are aware of this. I would question that even those that are would use this information for decision-making. As far as the reflex titer is concerned I had become aware of one reference lab that had a separate test number for an antibody ID without a titer reflex. Why anyone would order this is beyond me. There would surely be occasions in which this test would be ordered by mistake and create more problems than it was worth when the physician starts screaming for a titer result.

As a former employee of Ortho Diagnostic Systems Inc. (the "Rhogam" people) the information that we were given is that there is no evidence to suggest a correlation between the post-injection presence of anti-D and the effectiveness of the product. As far as I know nothing has changed since then to suggest otherwise. Another problem with using the antibody screen as an index is that there are so many different methodologies for antibody screening that whether anti-D is detected or may be totally dependent upon the protocol being used. On a side note the rule of thumb as far as I know it has always been that if the patient has not received Rh immune globulin within a six month period prior anti-D being detected then the anti-D is not due to the Rh immune globulin.

Sily, I wouldn't say that it's illegal in the U.S. to do an adsorption/elution with donor or patient anti-A,B but before monoclonal antisera came on the scene commercial antisera was used for this testing. The reason being was that reagent antisera was known to have a very high titer. Thanks for your comments and I wonder if anyone else who frequents this board might be using a patient/donor anti-A,B for their adsorptions.

Actually I'd never thought of this as being a significant problem in the past but nowdays it obviously is. My wife is a nurse in Maternity at the local health department. It is not uncommon at all to have women come in off the street with what are later found out to be aliases and/or bogus social security numbers. The nurses have been advised that they have no responsibility to question any of the information that they are given and should just treat the patient as a routine prenatal. It seems therefore that the practice of repeating previous ABO/Rh and antibody screening results may indeed carry some validity.

Jane, when you say "training" for that crossmatch procedure I assume that you mean that the techs are simply reading the new procedure and verifying that they have read it. I can't see that the addition of a second blood type requires any actual training. In the case where I have revised an SOP I just highlight or bold the revised part of the document to point out what has been changed and print out a copy for circulation to the techs. Attached is a generic form for them to sign that they have read and understand the revision. Of course with any SOP dealing with a brand new procedure you would probably be dealing with some type of training.

Your English is fine (But unfortunately my Chinese is not!). If you are using human source reagents I would continue to do what you are doing. The problem today is that as far as I know these reagents are no longer available commercially in the U.S..

I had been advised by the CAP office a few months ago that this "lot to lot" comparison requirement in the Immunology checklist was not intended to apply to blood bank reagents. The fact that "lot to lot" is not part of the Transfusion Service checklist backs that up. My understanding was that this checklist would be revised to take that into account. I'm not sure what the status is currently.

Thanks Shily! But if you are using monoclonal anti-A,B for the adsorption the 37C/Coombs part would not be applicable since the Coombs sera would not react with murine antibody. This is in contrast to the human source anti-AB that many of us older members of the profession fondly remember.

Does anyone have a good method for performing these adsorption/elutions using monoclonal antisera? We perform maybe 3 or 4 a year using an old method that utilizes an outdated polyclonal anti-A,B which is kept frozen. The procedure involves testing the eluate at a room temp incubation period and following that up with a 37C incubation and Coombs reading. The results have been mixed and eventually we'll run out of the polyclonal reagent. Thanks in advance.

We do the same, ARUP in SLC. If you don't do these on a regular basis it's impossible to get anyone to be proficient with the test. I was approached about doing these in-house several years ago but it would have involved less than 10 a year.

According to my interpretation of that JCAHO standard one should be QCing every vial of reagent opened. Since on any given day we wind up using multiple bottles of anti-IgG, LISS, Screening Cells, etc. this would require a separate QC on each bottle. If this isn't overkill I'm not sure what is. Fortunately we do not answer to JCAHO.

Why don't you call Immucor technical services and ask them? 1-800-492-2583. I'm guessing that it might have been a misprint in the article. Have the article at hand when you call and let us know what you found out.

Shily, First of all, don't worry about your English, it's fine. Secondly, as far as I know red cells of the subgroup Ael are only able to be classified by adsorption/elution studies using anti-A,B OR Anti-A. I've never heard of any antibody specific for Ael. Where are you getting your information about anti-Ael from? Have a good day!

First of all thanks for everyone's comments! Now for an update. The CAP will be modifying their IMM checklist to indicate that the item concerning lot to lot comparisons and patient-based parallel testing does not apply to the Blood Bank section.

That was exactly my impression Mabel. From the information that I get it appears that these customized lists are compiled and generated by the CAP without any input from the labs being inspected. Someone please correct me if I'm wrong!

My, this has become quite an interesting and lively discussion! I'm aware of the tailored checklists but unfamiliar with the mechanism used to tailor them. Is each institution being asked to tailor their own individual checklist or does the CAP just do a series of general tailorings which apply more or less to several facilities? Thanks again for your comments!

I am also a CAP inspector and I appreciate your comment but the bottom line is that the Immunology checklist does contain a small Blood Bank section. Personally I have never inspected any facility other than a hospital transfusion service so the Immunology checklist has never come into play. For a commercial lab performing only ABO/Rh and Antibody Screening well over 90% of the TRM checklist is not applicable

To clarify, the department in question is not a transfusion service but a commercial reference laboratory. They perform only limited blood bank procedures as well as some immunology (RPRs, cold agglutinins, etc.). As such the CAP has assigned the Immunology checklist.

Thanks for the response. The lab in question is a reference lab and has a department which is designated Blood Bank/Immunology. They perform ABO/Rh and antibody screening along with assorted Immunology procedures. Since this is the full extent of their blood banking the CAP inspects them using the Diagnostic Immunology checklist which includes a small section on blood bank.

Correction to my statement. The Immunology checklist does address this issue, stating that reagents must be parallel tested. I assume this statement encompasses all testing covered in that checklist of which ABO, RH and Antibody Screening are included. The TRM checklist does not address this. Basically it appears that depending upon which checklist you are inspected under you may be either cited or be home free.

I just heard from a local lab that they have been sited by the CAP for not testing new lots of reagents against patient specimens tested with the previous lot. Is this something a lot of people are doing? Isn't reagent QC before putting the lot into use enough? They are being inspected using the Immunology checklist as opposed to the Transfusion Service checklist but I see nothing in either that says patient specimens must be used for validating reactivity. Thanks!