Rh Pos to Rh Neg?

[Byfaith 21]

Hope some expert can shed some light on this.  Patient history O Pos, done on 3 seperate samples in 2009.  Patient received 1 unit rbcs in 2009.  Today, patient is O Negative, done on 3 seperate samples, one of which was a witnessed draw by myself.  Patient denies Bone marrow or stem cell transplant - diagnosis is CML.   My best guess, based on Google, is a rare phenomenon seen in CML patients due to a mutation?  Of course, she was given O Neg rbcs.

[Malcolm Needs ★ 4,512]

Sounds like either impersonation (had you seen the patient yourself before?) or rare case, as you suggest above.

[Malcolm Needs ★ 4,512]

The other thing could be that the clones used in the anti-D have changed, and they no longer detect a particular mutant type.

[Byfaith 21]

33 minutes ago, Malcolm Needs said:

Sounds like either impersonation (had you seen the patient yourself before?) or rare case, as you suggest above.

That thought crossed my mind also - 86yr old woman - who knows?! 

Regarding the clones in Anti-D reagent, the results in 2009 were 3-4+, but I guess strength doesn't matter if a clone is either going to react or not react with this particular patient.  Interesting case, whatever it is!

[Malcolm Needs ★ 4,512]

Certainly is.  If you ever get to the bottom of it - and sometimes you just can't - let us know please.

[BankerGirl 195]

We had a patient that seemingly converted from A Positive to A Negative.  We sent the patient to our reference lab and through whatever voodoo they do, discovered that she had proteins masking her D antigens.  I don't remember her specific disease process, and I don't think it was anti-D, but they reported that the patient was indeed A Positive.