Historical antibodies, now negative

[drsbright]

I would like opinions from the group regarding action to take ( or not) when historical antibodies have titered out and are no longer demonstrable. Case in point: 94 year old female, anemia of chronic disease, has received over 200 units over many years. Historically she had an anti-E, and warm autoantibody. For months, neither is demonstrable and her antibody screens and crossmatches are completely negative. Should the blood banker continue to screen units and provide antigen negative blood and perform the full Coombs crossmatch based solely on history?

SMB

[BSIPHERD]

Yes, you need to continue to give E negative blood. We continue to do AHG crossmatching for any patient with a history of an alloantibody. We would do a regular antibody screen.

Of course, if this patient went to a hospital that didn't have the history, he/she might get E Pos blood and then maybe you'd have an amnestic response.

[SMW]

Yes. Definitely.

[Bill]

We have a few patients just like yours and continue antigen test units and full IgG xmatch each time we transfuse them.

[Likewine99]

Yes, we do the same. Once they have an aby we always give ag neg blood compatible by AHG techniques.

[jhaig]

Absolutely. Once a patient develops an antibody, you always need to give that patient antigen-negative blood for that antibody. Otherwise you could stimulate production of that antibody again. Full crossmatches are also necessary. This is especially true for Kidd antibodies which are notorious for 'disappearing'.

[David Saikin]

Yes - antigen negative/ahg xm - - - it sounds like all of us are on the same page (as we should be).

Edited December 5, 2008 by David Saikin
poor spelling

[rescyth]

i agree with all of them. I just had the same situation last week. We gave the patient Ag negative and Xmatch comp units, by the way the AB screen also is negative for that patient. Rh other than D shows a dosage effect, together with other AB such as Kidd, Duffy and MNs...so maybe that explains it.

Edited December 8, 2008 by rescyth

[Antrita]

A month ago a new employee, had a negative antibody screen on a patient with a historical Anti-E. He did not screen the units he set up for her. She got one E positive unit. Before the second unit was issued a second CLS caught the error and screened for E negative units. We checked the patient at 1 week post, 2 week post, and 1 month for visable hemolysis, direct and indirect coombs. She continued to remain negative. We still had to report this to the FDA #QC-93-11. The hospital he worked before us did not keep antibody histories. It can be scary out there.

AntRita

[KKidd]

I have seen instances where the stimulation of giving an antigen negative unit can cause an increase in the antibody titer. Just imagine what an antigen positiveunit might do.

[Philip Thornton]

YES If this patient were to receive an E positive unit they would immediately make anti-E due to the immunogenic predisposition of having made anti-E in the past. We have patients exactly like yours with a history of Anti-E which are currently Ab screen negative that need antigen E negative units for each time. Just imagine if this patient traveled to another state and needed a transfusion. I would not wish to be the Blood Banker on duty during the probable massive hemolytic transfusion reaction.

[Mary**]

It would probaly be a delayed hemolytic reaction.

I also worry :fear:about "new" patients that have been transfused elsewhere. Our hospital was flooded in June and our patients were sent to many different surrounding hospitals to be transfused. Some of them went to more than one hospital. This went on for 5 months. I worried about those that had previously detected antibodies that were below detectable levels when we had them. We now have them all back :whew:and have to inquire about their transfusions elsewhere in the past 5 months. I console myself by remembering that this happens frequently in large cites where the patients go to different hospitals.

[Tony R]

When I trained in Blood bank many years ago we were taught that if the titer dropped to the point that the antibody couldn't be detected you had to be concerned with "amnestic response". This deals with the fact that once the patient has produced an antibody and the immune system still retains all the information it needs to quickly reproduce the antibody which will cause the titer to immediately increase if the antigen is reintroduced. Once we have identified a significant antibody that patient will always get antigen negative blood even if the AB screen is negative.

[Antrita]

I was really expecting a delayed transfusion reaction on this patient. She is a chemo patient so her immune system is depressed. Has anyone filed an event to the FDA like this one? I don't know what to expect. Also, since part of the root cause is the previous hospital this CLS worked at did not keep antibody histories on their patients, will the FDA want to inspect them?

Antrita

[luhubert]

You got all the right answers, but I can't imagine what prompted the question in the first place. all blood banking teaches that once an antibody, always an antibody. One of the answers was right on with the comment that it's a scary place out there. Can you imagine the amenestic response that woman might develop if she got E positive blood? I don't want to imagine it.

[ckcheng]

I agree with all of you. Standards says when clinically significant red cell antibodies are detected or the recipient has a history of such antibodies, whole blood or red cells shall be prepared for transfusion that do not contain the corresponding antigen and are serologically crossmatch-compatible.

However, if you come across a trauma case with massive bleeding in ER or OT which the patient has an antibody against a high incidence antigen (say anti-k) or has multiple antibodies (say anti-E, c-, -Jka, -S, etc). On hand you only find two units of antigen(s) negative blood and the surgeon said the patient is still bleeding. What should you do cuz the blood you give will probably bleed out right away? Should you give out the two units of antigen-negative blood immediately when call? Or talk to the surgeon to save that two units of antigen-negative blood till the bleeding is control, and by the mean time, give only ABO and Rh compatible blood?

CK Cheng, MSc, SBB(ASCP), CQA(ASQ)

Dec 2008

[sshel55]

In the case of the trauma scenario we have elected to do as you suggest, CKCheng, and save the antigen negative units until the patient's blood loss has slowed. This has worked remarkably well for us on several occasions with rapid blood loss in the OR. Patients who are rapidly bleeding may exhibit immune tolerance over patients who are given units to manage chronic anemia. This is a medical judgment call that should be made by the medical director of the blood bank.

As for the initial question that started this thread. AABB Standard 5.14.3 says it all.

[Eagle Eye]

YES. You need to give antigen negative unit and do full crossmatch/extended/AHG crossmatch.

[Eagle Eye]

You got all the right answers, but I can't imagine what prompted the question in the first place. all blood banking teaches that once an antibody, always an antibody. One of the answers was right on with the comment that it's a scary place out there. Can you imagine the amenestic response that woman might develop if she got E positive blood? I don't want to imagine it.

The question was posted by individual from Indonesia...do not forget that there are many countries out there, where they even do not perform antibody screen routinely and give AHG crossmatch compatible blood. in this case they are doing antibody screens.

[NedB]

The warm auto will come and go, as will the Anti-E. The odds are the Anti-E is the result of a stimulus from a non-immune source (a natural ab), which puts a history of Anti-E of minor significance; however, it means the Patient is in the minority of the population who react to an antibody stimulus. These Patients must have an AHG crossmatch. They have already demonstrated they will produce an antibody, so should be tested through AHG.