The protocol in OBGyn Unit -Operating Theater in our hospital is to send cord blood sample after delivery for a new born screening (this include ABO/Rh and DAT).Once the baby is transferred to NICU from there, they will send again but this time the sample is from the baby and the request is the same. Is there a universal policy to send cord blood for ABO/Rh grouping?Because we encountered problems (ABO discrepancy)using cord blood sample.To confirmed the results we asked for second sample from the baby . Any comment?

Sounds like duplicate testing; hope you are not billing for both ABO/Rh tests, or else wrote up a good Medical Necessity in your procedure. If you are having a lot of problems typing cord blood, then the first question is 'Are you using gel?'. A lot of people report problems testing cord blood with gel. If not you may have to increase the washing for the ABO/Rh. Our limit for washing cord blood for DAT was 4 washes; but for ABO/Rh we have no limit - wash as many times as it takes. By ABO discrepancies are you referring to discrepant with Mother and/or presumed Father? With babies especially you should verify lack of reaction with Anti-A or Anti-B with Reagent Anti-A,B.

It should not be necesssary to test both cord blood and baby, and this is not required by accrediting agencies, except when transfusion is required.

We do testing on cord bloods only on request. For admitting panels for NICU, we require a heel stick sample and repeat the testing on that sample. In most cases, the NICU sample arrives before the cord blood, so we just cancel the latter.

I think ABO discrepancy is common in baby. What about the second specimen form the baby, is it matched?

No, that's why we asked for another sample.On the first sample we were getting weak A Rh pos.(after 6x washing)The second & 3rd sample was O Rh positve .

I have yet to find a L&D that can consistantly label cord blood samples correctly. We NEVER use a cord blood sample for NICU testing purposes. If you are getting that kind of discrepancy on cord blood testing my first thought is the inability of L&D to get the right label on the right tube.

thanks .

..it may also be that the cord blood sample was contaminated with maternal cells during the collection process (or may even contain maternal blood rather than cord blood). The contamination issue would explain the weak reactions and/or mixed field appearance. In my hospital days, if a Mom was Rh-neg and the "cord" sample typed the same ABO/Rh as the Mom, a second sample (generally a heelstick sample), would be obtained and tested before determining that the Mom was NOT a candidate for post-partum RhIgG. For example, if Mom was O Negative and cord tested as O Negative a second sample from the baby was obtained; if Mom was O Negative and cord tested A Negative, a second baby sample was not required. It wasn't often, but every few years, this protocol prevented a Mom from not receiving the post-partum RhIgG dose which was indicated...

We retyp all our CORD be two techs and two diff. techniques. All our neonates who needs transfusion, we require heelstick specimen.

We test every cord blood for ABO/Rh and DAT (IgG only).

If the mother has a significant antibody capable of HDN, we antigen type the baby and do an elution if indicated.

Our cord bloods come with a label from the mother with a cord blood sticker (if twins, then A and . When the cord specimen is collected, the newborn hasn't been registered yet, so labels for the baby aren't available when the specimen has to be labeled. The specimen is sent with a copy of the order for the baby with their ID numbers, linking them to the right mother. Any discrepancy, we collect a heel stick.

To avoid false positive reactions from whartons jelly, we take 6 drops of cord blood , wash 4x in cell washer and make a cell suspension with that (a very small one)

Perform -A, -B, -D with 1 drop of suspension.

Place 1 drop cell suspension in IgG tube, and wash an additional 3x, add coombs, spin

ABO discrepancies with cord blood specimens can also be caused by a significant FMH.

We have seen weak reactions with monoclonal anti-A on at least 3-4 babies a year, and suspect an A subgroup, but cannot confirm with A1 Lectin, as it's not recommended for use on newborns. The A antigen is not fully developed yet. Incubate 10-15 minutes at room temp and recheck. Check the mother for subgroup of A. Every time it happened to us, that was the case. Mother was A2 or lower.

We only test cords of Rh neg moms or group O moms, or if mom has an antibody capable of HDN.

We do the same procedure as GilTphoto - no reverse group (as any anti-A and anti-B are probably mom's) and incubate the front type if weak. Ditto for the subgroups of A - no lectins, though we do use anti-A,B if necessary - same as an adult subgroup testing.

We do ABO/RH and DAT using cord blood on all newborns in our facility. We do our testing in Gel. We have had no significant problems. When transfusion is necessary, neonates are transfused with leukoreduced O negative units.

The protocol in OBGyn Unit -Operating Theater in our hospital is to send cord blood sample after delivery for a new born screening (this include ABO/Rh and DAT).Once the baby is transferred to NICU from there, they will send again but this time the sample is from the baby and the request is the same. Is there a universal policy to send cord blood for ABO/Rh grouping?Because we encountered problems (ABO discrepancy)using cord blood sample.To confirmed the results we asked for second sample from the baby . Any comment?

Have you considered using only the healstick sample for newborn screening instead of the cord blood as opposed to doing this procedure twice? You would have an accurate ABORh and still be able to detect a positive DAT.

We only test cords of Rh neg moms or group O moms, or if mom has an antibody capable of HDN.

Kate, do you have a reference for just testing Rh neg moms or group O moms? I'd like to just do those samples, but can't find anything in the technical manual. Also, do you charge a type on the mom if you don't have one before you perform the DAT and type on the cord blood?

Thanks, Mari

The AABB booklet on perinatal testing is great--sorry I can't think of the title right now. It makes an excellent case for doing no routine testing on newborns except an Rh type on those born to Rh neg moms to see if Mom needs RhIG. Any other testing is done only if the baby gets jaundice or needs a transfusion because any more is not cost-effective. Not doing the test to start with could remove the possibility of these discrepant results between different collections.