About an hour ago we received a call about a possible delayed HTR. The patient has slightly elevated LDH as well as the following:

DAT: AHG + IgG + C3 - (check cells checked)

Eluate: Positive for anti-C and anti-Fya

The patient has a history of several antibodies, anti-C and anti-Fya and a nonspecific WAIHA among them.

They've received several transfusions in the past month and received a particularly horrible bump one time in particular.

We've antigen-typed all of the transfused units' segs and all are antigen negative for C and Fya.

Thoughts?

what is in serum? How come you have anti-C & anti-Fya in eluate if you are giving C-, Fya- negative units? Unless patient received transfusion somewhere else with C+ &/or Fya+ units????

Is there any drop in hemoglobin? How about bilirubin?

About an hour ago we received a call about a possible delayed HTR. The patient has slightly elevated LDH as well as the following:

DAT: AHG + IgG + C3 - (check cells checked)

Eluate: Positive for anti-C and anti-Fya

The patient has a history of several antibodies, anti-C and anti-Fya and a nonspecific WAIHA among them.

They've received several transfusions in the past month and received a particularly horrible bump one time in particular.

We've antigen-typed all of the transfused units' segs and all are antigen negative for C and Fya.

Thoughts?

The positive DAT and the raised LDH could just be as a result of the WAIHA, but that doesn't explain the anti-C and anti-Fya in the eluate. Could they have received blood elsewhere that could have been C+ and/or Fy(a+)? Of course, the anti-C could be an anti-C-like antibody, related to the WAIHA, but that is less likely for the anti-Fya.

The other thing is, have you recross-matched on the latest pre-transfusion sample? I just wonder if there is a third antibody present that is directed against a low incidence antigen that was expressed on the red cells of one of your units, but not on either your screening cells or your panel cells.

Well, that's the immediate thoughts exhausted!!!!!!!!!!!!!!!!

Thank you both! No clear explanation still today!

I should have mentioned before that this patient was also at one point found to have PNH (though his most recent PNH screen was negative), has received an out of group bone marrow transplant (historically A pos with an O pos BMTS) and receives washed products (I'm assuming by physician request because of the PNH history to wash complement out of donor blood?). Though his bmts hasn't fully engrafted, our automated instrument typed him as a clean O pos. Mixed field was observed during a tube ABORh recheck however. His caretakers seem to be focusing on this as a possible culprit since he IS producing anti-A and is still producing some A pos cells.

I took a look at the eluate today and two C positive cells were unreactive with the eluate. One was an RzR2 but the other was an r'r. All of the Fya positive cells were reactive. A work-up from early in May had some stray reactions that were attributed to an HTLA (but it only titered to 4) but it hasn't demonstrated in work-ups since then. Their bilirubin and LDH ARE slightly elevated but not enough to raise huge flags (particularly considering the warm auto).

Both of the units transfused on the 24th were crossmatch incompatible yesterday with slightly positive reactions. Since it was both of them, I'm guessing that that sorta rules out the possibility of a low incidence. We don't have a pre-transfusion sample anymore unfortunately - our oldest samples are from the 8th and the patient was transfused here for the first time on the 7th.

According to the physician, the patient hasn't been seen elsewhere.

The positive DAT and the raised LDH could just be as a result of the WAIHA, but that doesn't explain the anti-C and anti-Fya in the eluate. Could they have received blood elsewhere that could have been C+ and/or Fy(a+)? Of course, the anti-C could be an anti-C-like antibody, related to the WAIHA, but that is less likely for the anti-Fya.

The other thing is, have you recross-matched on the latest pre-transfusion sample? I just wonder if there is a third antibody present that is directed against a low incidence antigen that was expressed on the red cells of one of your units, but not on either your screening cells or your panel cells.

Well, that's the immediate thoughts exhausted!!!!!!!!!!!!!!!!

Ah, the fact that the patient has received a BMT makes a huge difference!

The fact that the patient is still producing group A red cells, at the same time as producing an anti-A would, partly, explain the positive DAT (by the way, are they true group A red cells, or is it that his A substance, that he will continue to produce all his life - if he is a Secretor - is coating the transplant's group O red cells [is he Le(a-b+]? If it is the latter, you should be able to wash off the A substance or, if you incubate the red cells in plasma from a group AB or B Le[a+b-] plasma, the "A red cells" may disappear).

On the other hand, if the patient is genuinely producing "autologous" red cells, it could be that they are Fy(a+), and that the graft has produced an anti-Fya. Because of the positive DAT of the ceels, you would have to treat the patient's red cells with chloroquine diphosphate to see any mixed-field reactions with anti-Fya, if you don't know the patient's own pre-transfusion Duffy type - unless you have an IgM anti-Fya (only joking).

have y0u XM the segment with pre and p0st transfusi0n samples?