Hello

 

Received a call from a Physcian asking for a possible explanation when Mom has Anti-E and Dad is E negative.

History: 2 pregnancies including current with same Dad.

Physician had patient phenotypes performed Mom E- and Dad E-,e+

 

I mentioned the possibility of a natural occuring Anti-E, possibly performing genotyping for a variant E and paternity testing after the fact.

 

Anything else to consider?

 

Thanks and Merry Christmas.

 

Richard

 

 

Hi Richard,

There are three possibilities (from what you say).

The first is, of course, that the lady has, at some time in her life, received a transfusion from an E+ donor.

The second is, as you quite correctly say, a naturally occurring anti-E (a very common finding).

It could be that the lady is pregnant through another male and is too worried to admit this, but I have doubts about this, as it is highly unusual to detect an Rh antibody in a first pregnancy by a different male partner (and you would probably have your nose broken if you suggested this!!!!!!!!!!!!!!!!!!!).

I would suspect that the titre is quite low (am I correct?) in either case.

I have grave doubts about an E variant (although, of course, these do exist) as they are very, very rare.

What method are you using for antibody detection? I'm thinking of the "gel Anti-E" scenario. Weakly reacting, only detectable by gel or enzyme treatment.

Also, don't discount the paternity issue.  I have seen this before where the doc knew both parents were Rh Neg but the cord was Rh Pos, as was a heel stick specimen.  The mother was an OB nurse and the doc gave her the shot himself (and presumably received the rest of the story).

I remember a long time ago having a male med tech student (never transfused) with anti-E. Of course, have also seen other probably naturally occuring anti-E's over the years but this one we knew for certain. Not uncommon as mentioned above. Fortunately the baby in your case will be E neg.

We actually had a patient like this and we have had her though 2 pregnancies.  The first time around we were all nervous because the anti-E was 4+.  Very strong.  We monitered her every month (the titers never increased), had the dad tested (which he was Big E negative).  Baby was born and baby was big E negative as well.  Of course we maybe thought a little funny business was going on, but we had to trust the mother that everything was as it should be. 

 

I was in a conference once where they stated that this can occur during pregnancy?  Naturally occuring anti-E during pregnancy.  I was like hey we had one of those!  We never have blood from her when she is not pregnant, so I haven't been able to test it to see if it goes away.   It was interesting.  Scary at first, then interesting. (I actually had a nephew who had hemolytic disease of the newborn with kernicterus-which later we learned was more due to a brain bleed then antibodies, but none the less I am a little sensitive to HDN as I am sure we all are) 

Thank you for your replies.

 

The titre is quite low and the method is gel.

 

Malcolm, if television dramas which depict some pretty morally debased individuals are a true reflection of our contemporary society, your third possibility may require some further investigation. However I'm going with the naturally occurring Anti-E instead of the unnaturally broken nose.

 

Thanks

 

Richard

Is there any possibility that this is an Anti E like antibody and not an actual Anti-E? The reason I ask is that we recently had a case where our reference lab sited an Anti-C like specificity and did not call it an Anti-C.

In a word Ronald, YES!

Is the patient Rh negative and has she received Rh Immune Globulin? I had a close relative who had a very weak anti-E following her Rhogam injection, and it soon became undetectable. At that time the product insert stated that other antibodies could be passively acquired by this injection. (I can't find the statement in our current product insert.)

What Winter said ^

Is the patient Rh negative and has she received Rh Immune Globulin? I had a close relative who had a very weak anti-E following her Rhogam injection, and it soon became undetectable. At that time the product insert stated that other antibodies could be passively acquired by this injection. (I can't find the statement in our current product insert.)

 

Good reminder!

Once in a while we outdate RhIG (Rhophylac). I'll dilute it a bit and give it to my students. It always seems to have anti-C (or G) as well as the anti-D.