Re: Antenatal Rhogham
From: zygote@icsi.net
Sat Mar 25 09:27:47 2006
Yes, you are correct. The determination of antibody in the indirect Coombs is
appropriate for the issue of prevention of acute hemolytic transfusion reactions, but it
does not detect very low levels of antibody.
John Bowman in Winnipeg used an autoanalyzer which is much more sensitive that
the IDC to detect antibody. It is not the std of care to use that sensitive equipment. Do
a search under Jon and you will find a wealth of articles.
RJC
On 25 Mar 2006 at 9:52, Dean Huffman . wrote:
Date sent: Sat, 25 Mar 2006 09:52:51 -0600
Send reply to: ob-gyn-l@obgyn.net
From: "Dean Huffman ." <dean@thehuffpeople.net>
To: Multiple recipients of list OB-GYN-L <ob-gyn-l@dns.obgyn.net>
Subject: Re: Antenatal Rhogham
> .
>
> Thanks for the information.
>
> It has been my experience that most patients who received antenatal rhogam have
> a negative titer at the time of deliery. I wonder whether the lab, using more
> sensitive tests, might not find the antibodies in low levels. If, however, the
> antibodies are negative at delivery, that would imply that at some point before
> delivery the titers were low and the patient would be succeptable to
> "immunological enhancement". Since it is very rare for a patient to become
> sensitized, apparently immunological enhancement is not much of an issue with
> RhD immune globulin (RhoGam). I will look at the literature and see whether
> there is anything written about it.
>
> This might be a good resident research project -- antibody levels at delivery of
> patients who received antenatal RhoGam.
>
> Dean Huffman
>
> - - - - -
>
> Date: Fri, 24 Mar 2006 19:22:15 -0600
> From: zygote@icsi.net
> Subject: Re: Antenatal Rhogham
>
> The concept is referred to as immunological enhancement and has been stated for
> many years. Small volumes of Ab bind with hapten and instead of destruction and
> removeal from circulation are processed with primary immune response as result
> with formation of endogenous Rh ab.
>
> It is better to have excess antibody that two little ab. As someone who has
> published and does IUT's for really sick alloimunization with severe anemia -
> no fun! Prevention is better.
>
> Hope this helps - reference exists but have not loked for it for years!
>
> Bob
>
> On 24 Mar 2006 at 18:39, Dean Huffman . wrote:
>
> Date sent: Fri, 24 Mar 2006 18:39:48 -0600
> Send reply to: ob-gyn-l@obgyn.net
> From: "Dean Huffman ." <dean@thehuffpeople.net>
> To: Multiple recipients of list OB-GYN-L
> <ob-gyn-l@dns.obgyn.net>
> Subject: Re: Antenatal Rhogham
>
> > .
> >
> > I seem to have heard at one time, although I could never find a printed
> > reference, that the time of greatest risk for sensitization is when the IgG
> > titers from RhoGam are extrememly low, but not yet absent. Has anybody else
> > ever heard this? If so, do you have a reverence?
> >
> > - - - -
> >
> > Date: Fri, 24 Mar 2006 10:29:56 -0600
> > From: doctorjoe@aol.com
> > Subject: Re: Antenatal Rhogham
> >
> > Interesting problem and one cannot be unsympathetic.
> >
> > Still, the risk of sensitization with this pregnancy, and then with possible
> > effects on subsequent gestations, fairly mandates some action.
> >
> > The least expensive course might be to obtain the indirect Coombs first and
> > detect any residual antibodies, which, if present, would indicate ongoing
> > levels of RhoGam "protection". This would obviate the need for redosing
> before
> > delivery, which would at least save the cost of the RhoGam now.
> >
> > On the other hand, if the screen is negative, then she needs another dose.
> > Right?
> >
> > Joe P.
> >
> > -----Original Message-----
> > From: igold@cox.net
> > To: Multiple recipients of list OB-GYN-L <ob-gyn-l@dns.obgyn.net>
> > Sent: Fri, 24 Mar 2006 10:19:01 -0600
> > Subject: Antenatal Rhogham
> >
> > I saw a patient today who received her Rhogham a bit early, at 25 4/7 weeks.
> She
> > is 37 weeks now. Would anyone recommend repeating her rhogham since it has
> been
> > 12 weeks and she is unlikely to deliver imminently? Thanks, Ingrid Gold,CNM
> PS
> > She is uninsured and poor (and undocumented so ineligible for prenatal
> > entitlement services), so would have to pay out of pocket for the bloodwork
> and
> > Rhogham.
> >
>
> Robert J. Carpenter, Jr. MD
> 6624 Fannin, #2720
> Houston, TX 77030
> (O) 713-795-4600
> (F) 713-795-4422
>
> "Life is difficult"
> The Road Less Travelled
> by Scott Peck
>
Robert J. Carpenter, Jr. MD
6624 Fannin, #2720
Houston, TX 77030
(O) 713-795-4600
(F) 713-795-4422
"Life is difficult"
The Road Less Travelled
by Scott Peck
