CAP standard for Rhogam Work Up

[Jane12]

Hello All,

Is there any CAP/AABB standard that approves the use of mini panel for positive screens for Anti-D due to Rhogam administration. We currently perform a full panel & rule outs for Rhogam like any other clinically significant antibody. I would like to implement the change to selected panel but, would need a valid justification for my medical director. Thanks for your time & input. 

[EAB81]

This is just my opinion, but I would imagine that since there isn't a standard that absolutely demands that antibody screens are to be performed for the Rhogam Workup, working up a positive would be at the discretion of your medical director. We've been looking @ eliminating the absc when working up postpartum samples from mothers who are Rh neg  . We contacted the AABB, and they have stated that the standard 5.30.2 doesn't speak to it (requiring the antibody screen) because it's considered medical practice. I think what we're going to start doing is only performing abscs for those mamas who have had no prenatal care or no antenatal rhogam.  Of course, if they have history of antibodies we'll still do it--just in case.

[Kathyang]

  We do the cells with the @ behind it since a RhoGam D is not a clinically significant antibody. We also make sure the patient received RhoGam before found this short panel.

[Ward_X]

I've seen after the T/S is performed, if the screen is positive it bounces to a selected cell panel that is pre-made and validated (and usually ends up being around 5, 6, or 7 cells long). An inconclusive Passive-D panel results in further workup/rule-out. Even Rh+ pts with a Passive-D due to RhIg will get Rh= products until their screen is negative.

Is RhIg/WinRho not theorized to act as a previously identified antibody that can use selected rule-out? If a pt has an anti-E or anti-K for example, I've also seen pre-made mini E,K panels. Otherwise, I don't know specific regulations you can use as an argument.

[David Saikin]

On ‎08‎/‎25‎/‎2019 at 9:26 AM, Kathyang said:

  We do the cells with the @ behind it since a RhoGam D is not a clinically significant antibody. We also make sure the patient received RhoGam before found this short panel.

We run selected cells when we anticipate anti-D secondary to antenatal RhIg.  We still r/o the clinically significant abs w these cells.

Otherwise, we do not perform an abscr as part of our RhIg workup (post-delivery).

[TreeMoss]

If we've done a type and screen pre-delivery, we only test the mom for a feto-maternal bleed on a post-delivery specimen.  We don't repeat the antibody screen in those situations.

If there was no type and screen done pre-delivery, we will do the complete workup post-delivery.  If that antibody screen is positive and matches the pattern of anti-D, we check with the nurses to see if the patient received ante-natal RhIG and when.  We report out the positive antibody screen and comment that the positive results are probably due to Passive anti-D from RhIG given (date).  We also comment that the antibody will be identified if requested by the physician.  No physician has ever requested that we do an antibody identification on these patients.

I did an inspection once where the blood banker was working up a patient who had anti-M.  She choose only selected cells that were M negative to do the panel on in order to see if the patient had formed any other antibody.  This is not currently our practice, but I was interested in that procedure.  That would be the same as testing those cells marked with @ on the panel to see if anything besides anti-D was present, I guess.

[David Saikin]

18 hours ago, TreeMoss said:

I did an inspection once where the blood banker was working up a patient who had anti-M.  She choose only selected cells that were M negative to do the panel on in order to see if the patient had formed any other antibody.  This is not currently our practice, but I was interested in that procedure.  That would be the same as testing those cells marked with @ on the panel to see if anything besides anti-D was present, I guess. 

that's the way should deal w a known antibody.  You don't have to prove it is still there because you are going to respect its presence regardless.  Running ag negative cells to r/o other specificities is the way to go. (At least it's the way I've gone for the past 30+ years).

[Jane12]

Thanks for all the valuable information as well as for sharing your thoughts & work flow. I will present my case to our Medical Director as stated below: 

"Since Anti-D due to Rhogam administration is a passive antibody, it would be acceptable to perform an antibody screen with r-set panel cells ( as indicated by the manufacturer). If the screen is negative with r-set, further workup is not necessary. A result comment with the date of Rhogam administration needs to be added. If there is no evidence of Rhogam administration or if the r-set screen is positive, full work up is necessary. "

Please, correct me if I am missing anything. 

[David Saikin]

I have always found the "r" set to be lacking for rule outs.  In my current lot, I couldn't r/o Fya because there is no Fya+ cell in that set, also not a good zygosity for MNSs group.

I usually select the cells I want run when we expect anti-D due to RhIg administration.  I try to limit it to 6 including the auto control but there are times when I need 7+auto.  I write the cells to use directly on the box so there can be no doubt.

 

[Mabel Adams]

31 minutes ago, David Saikin said:

I have always found the "r" set to be lacking for rule outs.  In my current lot, I couldn't r/o Fya because there is no Fya+ cell in that set, also not a good zygosity for MNSs group.

I usually select the cells I want run when we expect anti-D due to RhIg administration.  I try to limit it to 6 including the auto control but there are times when I need 7+auto.  I write the cells to use directly on the box so there can be no doubt.

 

I agree with David.  We don't do an antibody screen for RhIG workup anymore because it doesn't change what the patient gets.  If it is positive they get RhIG and if it is negative they get RhIG. In the rare situation that there is some other antibody that is significant it could be found after the baby is jaundiced just like it would be for your A pos moms.  Our current policy is T&S on all OB admits so the latter doesn't apply to us.  We identify about 5-6 cells as a selected panel to run for moms with positive screens and suspected RhIG exposure.  One caveat: both of the D+ cells on the screen need to be positive or else the selected panel needs to include another D+ cell similar to the screen cell that didn't react (usually the R1R1 cell).  Otherwise, you could call a weak Anti-E showing dosage passive anti-D by mistake. Statistically, as long as  you have at least 5 negative reactions (D- cells) and reactions with at least 2 D+ cells, you can call it anti-D (passive or otherwise).

[slsmith]

We use  the cells on from the panel with the @ as long as we know the patient has received rhig. Also it is documented in the Blood Bank Patient History that you can not use this work up for transfusion purposes.

[David Saikin]

4 hours ago, slsmith said:

We use  the cells on from the panel with the @ as long as we know the patient has received rhig. Also it is documented in the Blood Bank Patient History that you can not use this work up for transfusion purposes.

seems like a waste if you can only r/o anti-D.  If you run a few more cells you can r/o almost everything.   There is rarely a need to run an entire panel (I know, I still do on occasion).