Letty

I just answered this question.


My Score PASS  

Apologies, you are quite right, and i have edited my post.  Regardless of the ethics of performing the testing, i would still be interested to know how you can differentiate between the two.

Interesting idea?  Sounds like a stupid idea to me.

I just answered this question.


My Score PASS  

I just answered this question.


My Score PASS  

I just answered this question.


My Score PASS  

I just answered this question.


My Score PASS  

Hi Jermin
We took up FDNA testing just over a year ago but still test all cord samples from D negative mothers to confirm the accuracy of the FDNA results.  We perform a retrospective comparison of results on a weekly basis and have found a number of discrepancies during that time.  All of these discrepancies have been carefully investigated by us and IBGRL, where appropriate.  Two of them were false positive FDNA results whereby the phenotype of the neonate didn't match the genotype...this scenario (D negative baby following a D positive genotype test result) will occur, albeit rarely, owing to the presence of a non-expressed RHD gene.  We have also had two false negative FDNA results due to insufficient foetal DNA in the maternal blood sample.  By testing the cord the risk to the Mum was minimized as she was able to receive post-natal anti-D immunoglobulin.  Rather more worrying, two discrepancies have highlighted poor practice on labour ward - a cord that was sampled from the sluice (yes, really) that IBGRL was able to show couldn't have belonged to the mother in question and twins who were initially both grouped as D negative but patient recall showed one of the them to be D positive!  By testing the cord and feeding-back any discrepancies to IBGRL it also helps to inform the accuracy of the test.
Although we group the cord samples, we stopped performing DATs on these samples many years ago and only perform a DAT in the presence of maternal antibodies or for clinical investigation of jaundice.
 
Hope this helps
 
Letty
 

Hi Jermin
We took up FDNA testing just over a year ago but still test all cord samples from D negative mothers to confirm the accuracy of the FDNA results.  We perform a retrospective comparison of results on a weekly basis and have found a number of discrepancies during that time.  All of these discrepancies have been carefully investigated by us and IBGRL, where appropriate.  Two of them were false positive FDNA results whereby the phenotype of the neonate didn't match the genotype...this scenario (D negative baby following a D positive genotype test result) will occur, albeit rarely, owing to the presence of a non-expressed RHD gene.  We have also had two false negative FDNA results due to insufficient foetal DNA in the maternal blood sample.  By testing the cord the risk to the Mum was minimized as she was able to receive post-natal anti-D immunoglobulin.  Rather more worrying, two discrepancies have highlighted poor practice on labour ward - a cord that was sampled from the sluice (yes, really) that IBGRL was able to show couldn't have belonged to the mother in question and twins who were initially both grouped as D negative but patient recall showed one of the them to be D positive!  By testing the cord and feeding-back any discrepancies to IBGRL it also helps to inform the accuracy of the test.
Although we group the cord samples, we stopped performing DATs on these samples many years ago and only perform a DAT in the presence of maternal antibodies or for clinical investigation of jaundice.
 
Hope this helps
 
Letty
 

Hi Jermin
We took up FDNA testing just over a year ago but still test all cord samples from D negative mothers to confirm the accuracy of the FDNA results.  We perform a retrospective comparison of results on a weekly basis and have found a number of discrepancies during that time.  All of these discrepancies have been carefully investigated by us and IBGRL, where appropriate.  Two of them were false positive FDNA results whereby the phenotype of the neonate didn't match the genotype...this scenario (D negative baby following a D positive genotype test result) will occur, albeit rarely, owing to the presence of a non-expressed RHD gene.  We have also had two false negative FDNA results due to insufficient foetal DNA in the maternal blood sample.  By testing the cord the risk to the Mum was minimized as she was able to receive post-natal anti-D immunoglobulin.  Rather more worrying, two discrepancies have highlighted poor practice on labour ward - a cord that was sampled from the sluice (yes, really) that IBGRL was able to show couldn't have belonged to the mother in question and twins who were initially both grouped as D negative but patient recall showed one of the them to be D positive!  By testing the cord and feeding-back any discrepancies to IBGRL it also helps to inform the accuracy of the test.
Although we group the cord samples, we stopped performing DATs on these samples many years ago and only perform a DAT in the presence of maternal antibodies or for clinical investigation of jaundice.
 
Hope this helps
 
Letty
 

I just answered this question.


My Score PASS  

I just answered this question.


My Score PASS  

I just answered this question.


My Score PASS  

I just answered this question.


My Score PASS  

David, the anti-D has been issued gradually over the course of the last few weeks in response to the persistent presence of foetal cells.  BCSH guidelines state that further anti-D should be given as dictated by the volume of foetal cells remaining, hence the disproportionate volume of anti-D given.