Hello

How do you rule out clinically significant antibodies when the antibody screen is positive due to RhIG? 

Thanks

 

Richard

 

You run antibody ID panels, just as you would for any positive screen, and ID what is there.  

Scott

You could do a selected cell panel.  Just make sure you cover all the antigens that are required in Canada.  Here it is DCEce Kk FyaFyb JkaJkb LeaLeb P1 and MNSs, I think.  Immucor has a 20 cell panel that has the upper ten cells are all D+, and the lower ten cells are D=.  Cells 11, 12, & 13 can be used to screen for antibodies other than anti-D.

We check for a 3 month RHIG history (probably could be longer but we chose 3 months).  If the ABSC is + we do a mini panel (Ortho panel has cells marked with * - Immucor has cells with brackets;  if negative rule out significant antibodies other than D. We then call it Anti-D RHIG.  This Anti-D only requires a full AHG crossmatch while it is demonstrating.  If patient returns ABSC Neg we can go back to electronic XM.

Thanks for the replies.

I thought maybe there was a new practice being adopted out there where you didn't have to rule out other antibodies, just confirm Anti-D in Moms having received Rhig. 

Heard rumblings in the greater Toronto area.

Thanks

Richard

I haven't heard anything, but I'm just outside of Toronto.  Interesting idea!  I'll keep my ear to the ground

 

Interesting idea?  Sounds like a stupid idea to me.

Here in the UK, not only do we perform an antibody ID but we also refer for quantification.  If the prophylaxis is detected in the 28 wk bloods then repeats are obtained as though the antibody were immune.  If it is detected for the first time after 28 wks then we refer for quantification but do no further testing if the antibody level is within the reference range for prophylaxis (unless detected immediately prior to delivery)

I would definitely rule out other significant alloantibodies in some way. Assuming that the antibody present is 'only' RhIG is asking for trouble. 99% of the time, it probably will be, but the time it isn't could bite you in the tookus.

there are plenty of reagents out there that allow you to cover all the other significant antigens on a mini-panel of D-negative cells