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What is your facilities protocol for doing HDN workups on Babies?

ABORh?

DAT?

Antibody Screen?

Lui Freeze?

 

Just curious what other places are doing as the hospital I interned in did not deliver babies, so never did HDN workups there.

 

Thanks,

CB

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Over the past 30+ years I've seen philosophies change dramatically on this subject.  At first we did an ABO, Rh, DAT on all babies born and if the DAT was positive we eluted and ID'd the antibody.  That evolved to just babies born to D Neg  and O Pos moms.  Eventually we came to the point where the only routine testing done on cord blood was the D testing on babies born to D neg moms.  Now if a baby started show signs or symptoms of HDN then the physician would order a workup to determine the cause which usually involved starting with a DAT on the baby and then moving forward if that was positive.  As a general rule if the DAT was negative then they would start looking in other directions for the cause.  

 

Not sure if this helps but there you have it.     :nod::no:

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We run a BTYSC...a baby type and screen. It includes a type, and we do not do the backtype for babies, a screen, and a tube DAT. If we get a pos DAT we look at the mothers TYSC. If the pos aby screen or DAT can be justified logically by the mothers results we do not continue. If we do not have a TYSC for the mother we request a draw or research her results at another instutution. We will do the ABID on the mother if at all possible to save the baby any draws. In the rare occasion there is no way to compare the mothers type and current screen then we might request another draw of the baby and or pursue the baby workup. The most complicated workup I remember was a baby with multiple antibodies and a positive DAT. One of the legends of Blood Banking, Jane Swanson, happened to be visiting and I listed off the antibodies found and she immediately rattled off the name of the mother...whose name was not the same last name as the baby...it had been over 10 years of retirement and her mental index and boundless knowledge is sharp as the day she left. So even in her 80s she can still problem solve for Blood Bank. So ultimately if we can solve the problem we do not continue with the workup.

 

I forgot to mention that most BTYSC are done for the babies in the NICU or for babies with moms who are RH neg. Otherwise we may have the cord blood sent to the BB with no tests ordered...just in case.

 

We are also giving all babies type O or O neg fresh(less than 7 days) Irradiated and, if there is/or mom has an allo antibody, antigen neg. We try to keep babies on the same RBC unit, so to reduce exposure to multiple donors that might go over 7 days, as long as they are not using over 30 mls per transfusion, if they are transfusing over 30 mls we use fresh RBCs(<7days). The BTYSC is good til they are >4 months. Also we continue Irradiated RBCs until 6 months. In the rare instance there is a non allo antibody that requires xm we can xm with the mothers plasma on a current xm and we continue as long as the DAT is pos. Our NICU has a fulltime lab staffed with a BB trained CLS. 

Edited by MERRYPATH
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Well David, it IS unusual, I know, but, if the HDN is clinically significant, and there are no detectable atypical alloantibodies in the maternal plasma, and the paternal ABO group is incompatible with the maternal ABO group (say, Dad group B, and Mum group A), I would perform a cord red cell/neonate red cell elution to see if the elution contains an antibody directed against a low prevalence antigen, the gene for which has been derived from the father.

 

This would not really affect the present baby, as it would be easy to find compatible blood for an exchange or top-up transfusion, but it would serve to alert the Obstetrician to a possible problem in any subsequent pregnancies.

 

I know, I know Mr Staley - horses and zebras again!!!!!!!!!!!!!!!!!

 

:bow:  :bow:  :bow:  :bow:  :bow:

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We do the Lui Freeze to identify the Immune Anti-A, Immune Anti-B or Immune Anti-AB. But when we do the Lui Freeze, as part of that test we are also running the cord serum against A1 or B cells (depending on Baby's and Mom's ABO) and Tube Screen Cells.

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We do front type and DAT on all cord blood samples as we use the BIORAD gel test, but we don't report DAT result for all. pediatricians usually ask for DAT if mother is Rh neg. or has known antibodies.

We have never done immune anti-A or -B. test  We do elution if pos.DAT cannot be explained by mothers type and/or baby will require transfusion.

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Actually Malcolm, Unicorns were my first thought. :rolleyes:

 

I have seen one case where the DAT was positive due to an antibody directed against an antigen specific to dad's RBCs.  This was the second or third baby born to this couple.  All cells tested were negative except the father's.  It was just a fluke that we thought to check dad's cells and he was available to provide a few.  As noted in my previous post the testing was performed due to the baby showing signs and symptoms of HDN and not part of routine testing.

Edited by John C. Staley
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Hi Yanxia,

 

The term is "when you hear hooves, look for horses, rather than zebra."  In both the USA and the UK, the only place you are likely to see zebra is in a zoo, whereas you may encounter horses all over the place.  In other words, what John is telling me to do is to look for the more common things first, rather than go straight for the unusual (and he is quite correct in this too)!!!!!!!!!!!!

 

The unicorn is a fictional animal that does not, therefore, exist, and what John is telling there is that I have gone for an even rarer scenario than even I normally do (and, again, he is quite correct so to do)!!!

 

I hope that helps.

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To completely mangle an already strained analogy and to offer support to Malcolm - two heinous crimes - zebras and unicorns are always likely to be detected less frequently by people who don't look for them.

Our routine testing is always going to be less exhaustive than that done by specialist laboratories on referred samples  in cases of special interest which is why they find wonderfully interesting things and get to, say, jet around the world telling people about them ...

 

Jealous ? Moi ?

 

(No. The inestimable Mr Needs very much deserves his reputation)

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Over the past 30+ years I've seen philosophies change dramatically on this subject.  At first we did an ABO, Rh, DAT on all babies born and if the DAT was positive we eluted and ID'd the antibody.  That evolved to just babies born to D Neg  and O Pos moms.  Eventually we came to the point where the only routine testing done on cord blood was the D testing on babies born to D neg moms.  Now if a baby started show signs or symptoms of HDN then the physician would order a workup to determine the cause which usually involved starting with a DAT on the baby and then moving forward if that was positive.  As a general rule if the DAT was negative then they would start looking in other directions for the cause.  

 

Not sure if this helps but there you have it.     :nod::no:

Ditto, ditto, ditto here.

The reality is that the Rh is the only test result we NEED if Mom is Rh-neg.  Of note, the Neonatologist at our hospital put in place a 'screening system' for determining which babies were jaundice.  As you all know, babies come in many colors so visual determination is highly 'unscientific' so a bilirubin is performed after so many hours and if over a threshold, another is ordered for another so many hours.  If this happens, they order the tests they need to help determine the cause of the elevated bilirubin (e.g. ABO/Rh/DAT).

PS We perform ABO/Rh/DAT on all babies born of mothers who have clinically significant antibodies.  This gives them a 'head start'.

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Actually Malcolm, Unicorns were my first thought. :rolleyes:

 

I have seen one case where the DAT was positive due to an antibody directed against an antigen specific to dad's RBCs.  This was the second or third baby born to this couple.  All cells tested were negative except the father's.  It was just a fluke that we thought to check dad's cells and he was available to provide a few.  As noted in my previous post the testing was performed due to the baby showing signs and symptoms of HDN and not part of routine testing.

This is precisely why instructions to check/test the father's RBCs is part of our Unicorn Tracking Protocol.  ;)

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Excellent question Phil, for which I have no definitive answer.  I would guess that the action of freezing causes a permanent change in the conformation of the antigen (it couldn't be the antibody, otherwise we would not be able to detect antibody in the eluate), causing the antibody to no longer be able to sensitise the altered shape of the antigen - but I am only guessing.

 

You've set me off on one now - I'll have to find out.

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We do a blood type and DAT. If the DAT is positive we do an antibody screen on the mother. If the mom is type O with a negative antibody screen and the baby is A or B we report this as presumptive evidence of ABO incompatibility. We stopped doing the LUI freeze thaw years ago. 

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