In your hospital, do you give rhogam to weakly D positive mothers without differentiating whether the mother is weak D or partial D? 

 

 

We don't do weak D on adults, so all Rh neg moms (with pos babies) get Rhogam.

We only do weak D to donors and babies .Same as pbaker.

We only do weak D on babies and donors. However, I have some pts (including 3 where I work) whose D typing in gel is marginally positive, tube testing D on these women is vw+ in all phases tested. They are A+ blood donors. 2 of them were OB pts and I told the docs we were going to give them RhIg and treat them like they were Rh=. Of interest is that I had the Quotient D typing panel. All three women had the same reactions with that panel, yet they aver they are unrelated. Interesting but of no clinical signficance as for as a Transfusion service goes.

I also think that one must interpret vw gel D rxs with caution. There are many and varied comments on how to interpret anti-D rxs <4+ in gel. One has to find a comfort level but be prepared to step out of the box for these margnal rxs.

Edited May 16, 201411 yr by David Saikin

We only do weak D on babies and donors. However, I have some pts (including 3 where I work) whose D typing in gel is marginally positive, tube testing D on these women is vw+ in all phases tested. They are A+ blood donors. 2 of them were OB pts and I told the docs we were going to give them RhIg and treat them like they were Rh=. ...........................

I also think that one must interpret vw gel D rxs with caution. There are many and varied comments on how to interpret anti-D rxs <4+ in gel. One has to find a comfort level but be prepared to step out of the box for these margnal rxs.

 

I agree with David and this is how we deal with the weakly reactive D issue and RhoGAM

We normally only do the immediate spin D typing. But will complete the weak D if a decrepancy is notied in the historical review, the FMHS is strongly positive, or if a request is make by the provider.

 

 In the bb computer, the weak D defaults to "D neg" on the displayed results (the at-a-glance bar in the Safetrace TX system) but ALL results and interpretations are easily retrievible. Additionally, we enter a comment in our historical comment section of the computer about the weak D status.

 

We provide Rh immune globulin to weak D moms.

Alana

Same as pbaker, and we do weak D testing on the baby, not the mom

 

We only do IS on Rh Neg mom's unless it doesn't match up with what the clinic typed them. Then we add on a weak D.

 

But when we result a Weak D pos it changes the patient to O Pos. Our procedure says Rh neg Du positive Mothers would not be a candidate to receive  rhogam.

 

But if we had no history and simply did an IS Rh we would type her as Rh neg and she would be a candidate for Rhogam.

 

Just because someone is Weak D Pos does not mean they cannot be sensitized to the D ag.  I think it would behoove you to re-evaluate  your policy on RhIg for these patients. (actually, that was the standard of care years ago, i.e., Du+ mothers did not get RhIg).

Re-evaluate to give RhIg to Du+ mothers?

14 minutes ago, amym1586 said:

Re-evaluate to give RhIg to Du+ mothers?

Yep!  There are some weak D's that predispose towards making anti-D if exposed to D+ rbcs (missing mosaic pieces, e.g.).  Only way to really know is with molecular testing - which right now is not really feasible at the community hospital level (or even tertiary care, as I have tried to bring it on board and offer it to the 15 - 500+ bed hospitals around me - not enough demand to make it work).

I used the Du nomenclature 'cuz that's what we called it when the policy was to not give RhIg to Du+ individuals.  Now the term is Weak D.

 

Sorry, but I am going to don my PEDANTIC hat again.  There is no such thing as an individual (male or female) who is D^u+.  There cannot be, as there is no such thing as anti-D^u.  When Dr Fred Stratton first described "D^u", he, together with Drs Rob Race and Ruth Sanger tried to separate anti-D from anti-D^u, and vice versa, and, of course, they could not so do, as anti-D was adsorbed out by D^u red cells and this proved that anti-D^u did not (and still does not) exist.

We know that Malcolm - I was using the terminology that was existing at the time when Du was being used AND that we did not give RhIg to Du+ individuals then.  Besides, whoever heard of anti-Du (not me)?

Was it always Weak D in Great Britain?

Aside from the Pedantics, what is your take on RhIg for Weak D individuals?  I do not routinely perform Weak D testing on maternity patients.

Edited December 22, 20159 yr by David Saikin

Would you forgo a fetal screen and issue RhIG  for an Rh Neg Weak D pos mother who gives birth to an Rh POS baby?

No David.  Sadly, it was in the UK that the term "D^u" was first coined (the "^u" bit standing for unagglutinable) by the above mentioned Fred Stratton.  It was a very interesting paper, as was that by Race and Sanger.

 

We do not give anti-D immunoglobulin for Weak D types 1, 2 and 3, but do for all other Weak D types and, of course, for ALL Partial D types.

Amy I would also recommend reading the manufacturer's instructions for your fetal screen kit. What does it say about weak D mothers, weak D babies, other special scenarios?

Amy - I do Kleihauers on Weak D Pos mothers.   We know they are weak D because the rosette is macroscopically positive.

Malcolm - how do you determine the Weak D types? and - is that something that you do in your reference facility or is it done in the hospital setting?

23 minutes ago, goodchild said:

Amy I would also recommend reading the manufacturer's instructions for your fetal screen kit. What does it say about weak D mothers, weak D babies, other special scenarios?

"If the mother is D positive, including weak D, strong agglutination provides no information about the extent of fetomaternal hemorrhage"

 

It doesn't expand any further. 

23 minutes ago, David Saikin said:

Amy - I do Kleihauers on Weak D Pos mothers.   We know they are weak D because the rosette is macroscopically positive.

 

We don't perform those in house. 

*sigh*

I've got my pathologist digging in on this now. 

28 minutes ago, David Saikin said:

Malcolm - how do you determine the Weak D types? and - is that something that you do in your reference facility or is it done in the hospital setting?

It is most certainly done in the Reference Laboratory, using the 10 anti-D reagents that are commercially available for just this testing (no names, no adverts), but an awful lot of our "bigger" hospitals now also use these reagents.  If they don't, then they send a sample to us (but give the anti-D immunoglobulin anyway this time, but will have our results available for any future pregnancies).

Is that the Alba product (quotient in the usa)?

1 hour ago, amym1586 said:

We don't perform those in house.

*sigh*

I've got my pathologist digging in on this now.

Unless you do these routinely your techs might have a hard time with this test.  I do them for 3 other hospitals and all my techs have to read the CAP survey slides after we submit them.  It is the only way to keep them confident.  The counting is abysmal to tell the truth.  I think the CV is around 40%.  Flow cytometry is the preferred method for quantifying the fetal/maternal hemorrhage.  Not going to happen in a small hospital like mine.

5 minutes ago, David Saikin said:

Unless you do these routinely your techs might have a hard time with this test.  I do them for 3 other hospitals and all my techs have to read the CAP survey slides after we submit them.  It is the only way to keep them confident.  The counting is abysmal to tell the truth.  I think the CV is around 40%.  Flow cytometry is the preferred method for quantifying the fetal/maternal hemorrhage.  Not going to happen in a small hospital like mine.

Yeah, I've done plenty of KB stains at my old hospital ( I don't miss them )

I've been here for a year and so far have not had one patient need one.

I just wonder if that will suffice to give one dose of RhIg to an Rh Neg Weak D pos mother of an Rh Pos baby.  Or if more testing is required.

I guess we are getting by with our procedure of them not being a candidate but I don't like that.

 

I still don't understand why there is so much gray area in blood banking. I feel like there should be way to do it and that is the way to do it. 

57 minutes ago, amym1586 said:

Yeah, I've done plenty of KB stains at my old hospital ( I don't miss them )

I've been here for a year and so far have not had one patient need one.

I just wonder if that will suffice to give one dose of RhIg to an Rh Neg Weak D pos mother of an Rh Pos baby.  Or if more testing is required.

I guess we are getting by with our procedure of them not being a candidate but I don't like that.

 

I still don't understand why there is so much gray area in blood banking. I feel like there should be way to do it and that is the way to do it.

Become accustomed to grey area.

5 hours ago, amym1586 said:

Would you forgo a fetal screen and issue RhIG  for an Rh Neg Weak D pos mother who gives birth to an Rh POS baby?

If we get a positive fetal screen we perform a weak D on the mother, and then look to see if the DAT is positive on the mother.  We would turn out the fetal screen as inconclusive and send the specimen out for a fetal Hgb F by flow.