Standing Deviation

[natalynn]

Hey Guys,

We've been touched by the Darzalex in our blood bank... so we've adapted and brought in DTT to try and aid in this situation. But here's my question, if a patient has an actual antibody (say anti-E) and we identify it using DTT and then do an extended crossmatch with E and Kell(CD38 destroys the Kell antigen), the crossmatch is going to be incompatible. To avoid performing our least incompatible procedure where we need a deviation signed each time, and transfuse 50cc then perform a DAT we were hoping to get a standing deviation for all patients recieving any CD38 monoclonal drug. BUT im not sure if this is ok to do... does anyone else out there have a standing deviation for anything in there Blood Bank. And if so would you mind sharing how it looks and what all needs to be on it for it to be kosher.

[heathervaught]

According to the AABB Association Bulletin 16-02, if you detect an actual antibody and need to do an AHG crossmatch, you can treat the K-/antigen- donor RBCs with DTT before doing the crossmatch.  If you have identified and honored all of the underlying allos, your AHG crossmatch would be compatible :-).

[David Saikin]

I concur with Heather

[Malcolm Needs ★]

23 hours ago, heathervaught said:

According to the AABB Association Bulletin 16-02, if you detect an actual antibody and need to do an AHG crossmatch, you can treat the K-/ antigen- donor RBCs with DTT before doing the crossmatch.  If you have identified and honored all of the underlying allos, your AHG crossmatch would be compatible :-).

I haven't read this Heather, but what if it is an anti-k or an anti-Kp^b or something like that?

[David Saikin]

19 hours ago, Malcolm Needs said:

I haven't read this Heather, but what if it is an anti-k or an anti-Kp^b or something like that?

I think the patient is going to be in trouble.  At this point there is not much we could be doing differently . . . except maybe type the patient for k along with the initial K typing.  Fortunately those k/Kpb neg pts should be few and far between.

[Mabel Adams]

I keep wondering why no one is mentioning antigen typing for k in any of these patients who is K pos.  I know the odds are low, but I have seen some anti-k antibodies in my career. We live in a mostly caucasian community also. I've never seen an anti-Kpb...yet. I suppose the best defense against that anti-Kpb is to genotype the patient so you know if they are negative for the antigen.

We plan to crossmatch DTT treated cells in this scenario and we will turn it out as compatible but with some sort of caveat that the test isn't perfect.  At least that is the current plan.  Maybe you all will change my mind.  My reference lab thinks that we should turn them out as incompatible. 

[goodchild]

On ‎6‎/‎25‎/‎2016 at 4:42 PM, Mabel Adams said:

I keep wondering why no one is mentioning antigen typing for k in any of these patients who is K pos.  I know the odds are low, but I have seen some anti-k antibodies in my career. We live in a mostly caucasian community also. I've never seen an anti-Kpb...yet. I suppose the best defense against that anti-Kpb is to genotype the patient so you know if they are negative for the antigen.

We plan to crossmatch DTT treated cells in this scenario and we will turn it out as compatible but with some sort of caveat that the test isn't perfect.  At least that is the current plan.  Maybe you all will change my mind.  My reference lab thinks that we should turn them out as incompatible. 

This is a hypothetical question because I was thinking the same way as you. What will you do if you find out the patient is negative for k or Kpb?

[Mabel Adams]

On 6/27/2016 at 8:53 AM, goodchild said:

This is a hypothetical question because I was thinking the same way as you. What will you do if you find out the patient is negative for k or Kpb?

I had planned to give them k neg units if they are k negative.  I think our blood supplier could handle that.  Since Kpb negative people are even rarer, I will probably handle that on a case-by-case basis.  In emergencies, I guess we would have to rely on the old in vivo crossmatch.  We take the same risk with antibodies to high frequency antigens when we do alloadsorptions on patients with warm autos. I guess that is one reason we might still call their crossmatches incompatible, although I also expect that the units will be incompatible to some degree with the autoantibody in the case of a warm auto patient.

[jmphil4]

Our plan for the patients is to do a preliminary type and antibody screen, along with a full phenotype, before they begin treatment. Once they begin the medication, we will perform elutions on the patients. This should allow us to identify any newly formed antibodies that wouldn't be detected with the DTT treated cells.