Rh Interpretation

[BANKTECH]

Hi!! Quick question for all of you. Does your facility distinguish a Weak D+ patient from an Rh+ patient in your LIS? Also which LIS are you using? Thanks so much!!:cool:

[Malcolm Needs ☆]

Well, we do (on Hematos), but you probably expect that from a Reference Laboratory.

[Justina]

No, the test will show up that you performed weak D testing, but the end result will just say Rh positive (Cerner).

[DPruden]

We have HCLL (Mediware) and we only report Rh negative or Rh positive, but we do not perform weak D testing routinely anymore, except on cord bloods.

[ChrisH]

Just like DPruden, but we are on HBB (Horizon Blood Bank)

We have HCLL (Mediware) and we only report Rh negative or Rh positive, but we do not perform weak D testing routinely anymore, except on cord bloods.

[Mabel Adams]

For anyone but babies (and problem resolution) we don't do weak D tests. If we have to do one on an adult, the Rh is interpreted as negative even if the weak D test is positive. We are on HBB.

[Malcolm Needs ☆]

For anyone but babies (and problem resolution) we don't do weak D tests. If we have to do one on an adult, the Rh is interpreted as negative even if the weak D test is positive. We are on HBB.

Ummmm, excuse me being stupid and asking Mabel, but then, if you are going to call them negative anyway, why do the test in the first place?

[BANKTECH]

Thank you for all the input!

[maristgo]

Hi,

Here we have Meditech c/s 5.65 (Gel and Tube Method) and we do the weak D and the system distinguish between a RH Pos and a RH Pos Weak D.

May i ask ... do you give to these patients RH Pos or RH Neg RBC?

In our facility we give to them RhNeg RBC.

Thanks for the information,

[tbostock]

We have SoftBank and we report Rh Pos or Rh Neg. The weak D is a separate result, but the tech selects the interpretation.

[BANKTECH]

Maribel,

Our policy is to give Rh Pos RBC.

[SMILLER]

Up to now, we do weak Ds on prenatals. If the coombs result is 2+ or greater, we would report it out as D Pos.

Recently we had a problem with how our reports are interpreted. We did a ABO/Rh/Ab screen for another lab that was weak D positive based on our protocol. However, this particular patient has had testing done at another hospital that never does weak D for prenatals, so we know that the doc already has previous reports saying the patient is D neg. Sent out the report with a comment, but we are not going to be surprised if the doc calls back for clarification.

Now we are debating talking to our pathologist about dropping weak D testing altogether. Any comments on that?

Thanks, Scott

[Deny Morlino]

I think dropping the weak D on prenatals would be wise. It is possible that the patient your lab has reported as rh positive when exposed to rh positive blood might form an anti-D. We would treat the patient as rh negative and administer RhIg and Rh negative products to prevent this possibility. We continue to check cord samples for weak D, but when we began using gel about 12 years ago the weak D protocol was dropped otherwise. Hope this helps.

[EDibble]

We have HCLL for our BB IS. We do weak testing only on cords, and on male partners of Rh negative women who are pregnant.

If a weak D were positive, in the cases above, the result in HCLL would show the weak D testing, but when crossing over into the LIS, Sunquest, it would show as Rh pos only.

We no longer do weak testing on prenatals. If the D is neg, they are Rh neg and would receive RhoGam if necessary, and Rh neg blood.

[Mabel Adams]

The only problem with not doing weak D on prenatals is the rare "diffusely positive" fetal screen/rosette test that requires some workaround. We haven't actually had that problem yet but someday it will appear. We are currently using a pretty sensitive anti-D that picks up more things at IS than some of the others so we want it to be quite strong before we will transfuse D+ blood.

[AMcCord]

We don't do the weak D on Prenatals. If we have a positive fetal screen, it gets a Kleihauer-Betke - mom is really weak D positive or there has been a large fetal bleed, either way, she still gets a Kleihauer-Betke. If the Kleihauer-Betke comes back negative on a rosette test that looked 'diffusely positive' or showed more than a few rosettes, then do the weak D and get that on her record for future pregnancies. (We would give Rh negative blood and RhoGAM to a weak D patient or anyone whose reactions to anti-D antisera or <2+.)

[adiescast]

We only do the weak D on cord bloods, putative fathers, mothers with a positive fetal screen, and patients with an RH positive autologous unit. We report the weak D positive as "Rh negative, weak D positive" in Sunquest. We give these patients Rh negative blood.

[Dr. Pepper]

We have dropped weak Ds on prenatal patients. We don't have L&D here, so we only do weak Ds on patients with questionable or ambiguous routine D typing results. We result them in Meditech as "Rh positive" but add a comment to the patient history "Patient is weak D positive - give Rh negative RBC". We, like others, have seen our share of weak D patients who have produced anti-D.

[Sfdreams]

We have Horizon BB and use ProVue (mainly) We do the same as Mabel: we do not test weak D anymore except on cord bloods. Also, when we get a result less than 3+ on the ProVue, we will check with tube, and report out the tube result. Therefore, we are calling more people Rh Negative than before, and they are receiving D- units. Occasionally, we run across patients whom we had typed as Rh Positive before, when we were doing Du testing, and we change them to Rh Negative with this comment:

“Rh typing on this patient is dependent on reagents used, tests performed, and/or technical performance. Patient may have been previously reported as Rh Positive or Rh Negative. For Blood Bank testing the patient will be treated as Rh Negative, a candidate for Rhogam, and will receive Rh Negative blood. As a blood donor, this patient will be treated as Rh positive.”

But for cordbloods, we ONLY do them on the ProVue or in MTS gel, so that if they are Weak-D the mom still gets Rhogam.

I believe we wanted to take a conservative approach.

For anyone but babies (and problem resolution) we don't do weak D tests. If we have to do one on an adult, the Rh is interpreted as negative even if the weak D test is positive. We are on HBB.

[BankerGirl]

We had a sample refered to us from another hospital yesterday. They typed the patient as O Negative and got a positive Fetal Screen result so they sent it to us for the Kleihauer Betke test. When we ordered the test, we saw that our history stated the patient was O Positive. Repeated testing in Ortho gel yielded 3+ results, with 1+ results in tube. This definitely gets confusing!