We have a patient with autoimmune aplastic anemia and hx of anti-E. This is our first time seeing her, and current ABSC and ABID are pan-reactive due to WAA. The autocontrol and DAT ( both IgG and C3) were positive and WBC count = 1.5 K/ul. Pre-transfusion Hgb was 6.2 and over last 2 days has rec'd 2 units of E-neg "least incompatible" RBCs. Her Heme Onc is now requesting all add'l units be both E-negative and K-negative. I was not able to reach her directly, but curious why she's requesting K-neg. Anyone see the connection? All I can think of is she doesn't want to risk alloimmunizaiton to K (we do phenotypically match C, E, K, Fya/b, and S for sickle patients), but wondering if there's another indication in this situation. (Also, why not irradiated given her current white count?). Thanks for any insight!

The first thing I would ask is, is the lady pre- or post-menopausal? That having been said, in the UK, we tend to give all patients who are likely to be chronically transfused, K Negative blood, whether they be male or female, unless, of course, they are known to be K Positive, purely because the antigen is so immunogenic.

As for your question regarding irradiation, that is much more of a clinically decision (I am not, and never have been a Clinician), but I can't see why the units should not be irradiated,

14 minutes ago, Malcolm Needs said:

The first thing I would ask is, is the lady pre- or post-menopausal? That having been said, in the UK, we tend to give all patients who are likely to be chronically transfused, K Negative blood, whether they be male or female, unless, of course, they are known to be K Positive, purely because the antigen is so immunogenic.

As for your question regarding irradiation, that is much more of a clinically decision (I am not, and never have been a Clinician), but I can't see why the units should not be irradiated,

Good morning, Malcom. Thanks for your reply- she is 61 yrs old and KNeg. I agree also with your approach, but we also have lots of patients with chronic anemias on transfusion support for whom we aren't giving K Neg. Maybe the dr. is just being more proactive in this case.

Thank you kjmiller. Could be the doctor is being more cautious/more proactive, but in the UK (and I have only ever worked in the UK) our Guidelines suggest/DEMAND that we give K Negative to a patient requiring chronic transfusion, unless they are K Positive (although, interestingly, they are silent on what to give if the patient is K+k-!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!).

Not an approach we would use. Alloimmunization rate in autoimmune diseases is generally quite low, including aplastic anemia.