Do other hospitals have a policy for handling passive Anti-C?
It is published in the Rhophylac package insert that Anti-C may also be present along with the Anti-D.
I work at a hospital with a High Risk Maternity ward and we often have moms-to -be here as inpatients for weeks or months before the baby is delivered due to complications.
Here is what happens at our lab: The mom gets RhIG (we use Rhophylac) at 27 weeks, or any time the MD decides to give another dose due to complications, and then a few days later we are running a type and screen if they are at risk for going into premature labor due to their complications.
Well yes, we do detect the Anti-D, but when the RhIG has been administered within a month or less, we often see the Anti-C as well. Especially on our ECHO. We do not use gel, we have PeG as our alternate method.
Where I am going with this is I am looking for more info from other labs on about how far out from the last RhIG dose are you seeing this passive Anti-C? In my experience, it is usually less than one month from the last RhIG dose. After it has been more than about 30 days, we usually no longer detect the Anti-C, only the Anti-D.
I wanted more information in order to develop a policy for when we can call it Passive Anti-C and when we need to treat it as a potential alloantibody. I was planning to make my cut-off date one month from the date of the most recent RhIG., and also the mom had to have had a negative antibody screen prior to the RhIG administration during the same pregnancy.
Any advice you might have would be welcome.
Probably the easiest thing would just be to run the panel with PeG and hope the Anti-C is not detected?