Incompatibility with adsorbed plasma

[mhinrichs]

We currently have a patient who is a woman of child bearing age (no pregnancies) with a diagnosis of GI bleed. She has a 5g hemoglobin of course, and has been transfused in the last week. Differential alloadsorptions removed the reactivity with the panel cells but when the crossmatches were performed in parallel with the adsorbed plasma they were incompatible with A+ units. We, however discovered today that type O+ units were compatible with the adsorbed plasma. Any thoughts as to why this may be? Patient types A1 positive and no issues with the reverse ABO type. Thanks for any input.

Monica

[Malcolm Needs ☆]

It is possible that the patient has an anti-ALe( that would not have been removed by the adsorption process as, I presume, this was done with group O red cells.

This is quite a rare antibody specificity, but, given that your patient is pregnant, and pregnancy can do funny things to the Lewis antigens (see the fairly recent review in Immunohematology - the exact citation escapes me at the moment).

[Malcolm Needs ☆]

Oops, sorry Monica, I've just reread your post, and you say she is not pregnant and hasn't been pregnant.

That notwithstanding, it could still be the specificity of the antibody.

[mhinrichs]

That is ok Malcolm and thank you so much for the info! We plan on doing some additional testing to investigate this possibility.

Monica