How do you report weak D positive ( in Rh blood group) for physician?

[mrkeramati]

When we encounter with this Rh blood group how to report it and what is you advise for kind of Rh if the patients need blood transfusion?

Edited February 26, 2016 by mrkeramati

[pbaker]

We do not weak D type our adult patients.  We treat them as Rh negative.

[mollyredone]

pbaker-Do you weak D type your babies?  We do if the mother is D-, but even if the baby is weak D+, we would report it as D- since we don't want a blood type discrepancy in the future.  On weak D+ babies with D- mom, we report that a fetal hemoglobin F should be ordered to confirm a bleed and that the mom is still a candidate for Rhogam.

[pbaker]

Quote

We only type babies of group O and/or Rh neg moms.  Yes, weak D typing is required for babies and we call them Rh pos.

 

[mollyredone]

So do you change their blood type when they are older, since you don't perform weak D on them?

[pbaker]

When they are adults, they will get run on our instrument (NEO) that picks up most weak D reactions, so they stay Rh pos.  If not, we will change their type and put a comment regarding testing methods and why the change. 

We have the same type issue when prenatals are done at outside labs that perform weak D (+) and then the moms come here to deliver and we don't (=).  Or a weak D blood donor (+) becomes a patient (=).  We just explain the discrepancy to the physician, call them Rh neg and offer them RhIg, if indicated.

I used to work in a facility that also collected autologous blood.  We were required to weak D donors units, but not patients, so sometimes that got really confusing when their blood type per blood bank is Rh=, but their unit is labeled Rh+.

[BankerGirl]

On 2/26/2016 at 0:29 PM, mollyredone said:

pbaker-Do you weak D type your babies?  We do if the mother is D-, but even if the baby is weak D+, we would report it as D- since we don't want a blood type discrepancy in the future.  On weak D+ babies with D- mom, we report that a fetal hemoglobin F should be ordered to confirm a bleed and that the mom is still a candidate for Rhogam.

We just had a baby come up weak-D pos and I had to decide how to report this.  I chose to go with Rh Neg and add a comment that the weak D was pos so mom needed RhIG.  It was easier to answer the RN's question once than to worry about changing the baby's blood type after dismissal or having questions later in life.

[Auntie-D]

On 2/26/2016 at 8:36 PM, pbaker said:

When they are adults, they will get run on our instrument (NEO) that picks up most weak D reactions, so they stay Rh pos. 

And what if they are partial and should actually be classed as rh neg?

[Malcolm Needs ☆]

I haven't contributed to this thread, for the simple reason that I have no idea how someone (patient or donor) can be weak D positive.  Sadly, in my laboratory, and, I believe, in my country, we do not have any anti-weak-D.

[Dansket]

19 minutes ago, Malcolm Needs said:

I haven't contributed to this thread, for the simple reason that I have no idea how someone (patient or donor) can be weak D positive.  Sadly, in my laboratory, and, I believe, in my country, we do not have any anti-weak-D.

If the Weak D test is positive on a newborn, we report the patient to be Rh Positive, if the Weak D test is negative, we report the patient to be Rh Positive.

[Malcolm Needs ☆]

2 minutes ago, Dansket said:

If the Weak D test is positive on a newborn, we report the patient to be Rh Positive, if the Weak D test is negative, we report the patient to be Rh Positive.

Ah, that's different - but some people are calling the patient "Weak D Positive" or "Weak D Negative" and, as I said, there is NO such thing as Anti-Weak-D.

[StevenB]

36 minutes ago, Dansket said:

If the Weak D test is positive on a newborn, we report the patient to be Rh Positive, if the Weak D test is negative, we report the patient to be Rh Positive.

Am I missing something?  "....if the Weak D test is negative, we report the patient to be Rh Positive."  Just checking.

I agree with Malcolm:  A patient is either Rh Positive or Rh Negative.  If you want to report it as Rh Positive at the weak D phase of testing, well...Ok, but the patient is still just Rh Positive.

[Malcolm Needs ☆]

26 minutes ago, StevenB said:

Am I missing something?  "....if the Weak D test is negative, we report the patient to be Rh Positive."  Just checking.

I agree with Malcolm:  A patient is either Rh Positive or Rh Negative.  If you want to report it as Rh Positive at the weak D phase of testing, well...Ok, but the patient is still just Rh Positive.

Thank you!

[Dansket]

2 hours ago, Dansket said:

If the Weak D test is positive on a newborn, we report the patient to be Rh Positive, if the Weak D test is negative, we report the patient to be Rh Positive.

My bad,  I intended to state, "If the Weak D test is positive on a newborn, we report the patient to be Rh Positive, if the Weak D test is negative, we report the patient to be Rh Negative.

[AuntiS]

Ok... but are we also talking about when there are weak reactions with anti-D?  Less than a 2+ reaction?  Because, here at our lab, we will send out a female of childbearing potential (less than 45 for us) out for genotyping.  Until those results come back, we treat her as Rh Negative.  Other patients get treated as Rh Positive.

We report out those patients as Rh Negative (override the blood group in the LIS), add a comment, and wait for the genotyping to come back. 

s