Jump to content
PathLabTalk

Standing Deviation


natalynn
 Share

Recommended Posts

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.

Link to comment
Share on other sites

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 :-).

Link to comment
Share on other sites

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-Kpb or something like that?

Link to comment
Share on other sites

19 hours ago, Malcolm Needs said:

I haven't read this Heather, but what if it is an anti-k or an anti-Kpb 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.

Link to comment
Share on other sites

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. 

Link to comment
Share on other sites

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?

Link to comment
Share on other sites

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.

Link to comment
Share on other sites

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. 

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share

  • Advertisement

×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.