Anti-D after RhIg injection

[Ardele Hanson]

Just wondering what others are doing in these cases? We have recently taken on a farily large OB/Gyn Practice. When an Anti-D is reported on and Rh-negative female of child bearing age, we call and find out if RhIg has been given. If the answer is yes, we make a note of the date of injection. We are seeing requests for titers on these....So, what do you do? It probably is not a good thing to put an Anti-D in the patient's permanent record....or to do titers on these .... but how do others proceed?

[adiescast]

If we have a patient who had a negative screen in this pregnancy, had documented RhIg injection, and now has an anti-D, we call it "Anti-D due to RhIg" and do not count it as a permanent antibody. If we do not have a prior screen this pregnancy, but have documented RhIg injection, we call it "Anti-D probably due to RhIg" and do not count it as a permanent antibody. If we have no documented RhIg injection, we call it "Anti-D" and it goes in the permanent file.

[Bill]

We do same as adiecast and if there has been documented RhIg injection, we do not titer

[AnneB]

Our practice is the same as the others who have replied.

[John C. Staley]

We had an OB go ballistic over this phrase. "Anti-D due to RhIg". Her point was that we could not know for sure and that was hard to argue. Because of this we waffled the phrase to say, "Anti-D most likely due to RhIg". As far as titers went, that was up to the ordering physician in these cases. If they ordered a titer we did it. Luckily, most never did. We routinely did titers only on clinically significant antibodies (as defined by the corporate transfusion service medical director).

:blahblah:

[bliss]

What do you think about this article about anti-d injections...

http://welladjustedbabies.com/common-questions-about-anti-d-injections/

...valid? It seems to be well-researched from what I can tell.

[Auntie-D]

We had an OB go ballistic over this phrase. "Anti-D due to RhIg". Her point was that we could not know for sure and that was hard to argue.

We use rr cells if we get a weak positive antibody screen after prophylaxis. It doesn't allow you to identify C or E but allows you to eliminate 'everything' else that would come up on a 3 cell screen. This coupled with a weak reacton would indicate prophylaxis. Allo-D would give a strong reaction anyway. I've found that a 3+ reaction in gel will give a titre of only 1:2 to 1:4 anyway... This is highly unlikely to be an allo.

So we can say with a reasonable degree of confidence that it is due to prophylaxis, especially if their 28 week sample didn't show C or E.

[AMcCord]

We check to see whether or not the patient has received RhoGAM. If they have, our statement is "Anti-D identified. Patient received RhoGAM mm/dd/yy." We do not make a statement as to whether the anti-D is immune or not - the physician can decide what he/she wants to do with the information. If the patient did receive RhoGAM, we don't consider it a permanent antibody unless strength of reaction or patient history leads us to suspect otherwise.

If the patient received RhoGAM, we would not automatically titer it. If the doc wants a titer, we'll do it, though we might have a chat (via a pathologist) with him/her to find out why they want the titer and to try and talk them out of it if the titer doesn't seem warranted. The OB/GYN folks almost never want the titer. an occasional Family Practice doc will.

We did have a patient a few years ago that was threatening to miscarry throughout her pregnancy. She received her first dose of RhoGAM early on, prior to a prenatal workup, and the doc wanted to monitor her with titers until she delivered. With her we started out not knowing whether she had immune anti-D or RhoGAM anti-D. Her initial titer was high enough that it was suspicious. A case like that says that sometimes the titer may be useful information. Without patient history, it's hard for us to know whether the titer is a good idea or a waste of time and money. However, a routine order to titer all anti-Ds with a history of RhoGAM does seem like overkill. Does the practice in question see mostly high risk patients? Communicating with the ordering physician(s) is likely the best way to address the issue.

Edited February 22, 2012 by AMcCord

[Malcolm Needs ☆]

Allo-D would give a strong reaction anyway.

Sorry Auntie-D, must I must disagree. We have several women who have had an anti-D with a level well below 1.0 IU/mL for years, pregnancy after pregnancy; the levels have never increased, despite D Positive pregnancies, and they have never had anti-D immunoglobulin. It can, and does, happen.

The bad news is, that we have also had women like this who, for some reason, suddenly produce a stonking anti-D with very high levels as measured by IU/mL.