gagpinks Posted April 22, 2016 Share Posted April 22, 2016 (edited) Hi Had a cord blood tested and found mixed field reaction in anti-A. No transfusion history during pregnancy. Also noticed many new born with no transfusion history have a mixed filed reaction in anti-A and/or anti-B. Is it due to fetomaternal haemorrhage or could be other reason? Edited April 22, 2016 by gagpinks Link to comment Share on other sites More sharing options...
R1R2 Posted April 22, 2016 Share Posted April 22, 2016 I have seen this numerous times and is most likely due to the A antigen not being completely developed on newborn RBCs. I have seen a fetomaternal hemorrhage do this once in my career but it was detected in the D tube test. Can you look up mom's HGB pre and post delivery? Link to comment Share on other sites More sharing options...
gagpinks Posted April 22, 2016 Author Share Posted April 22, 2016 Sorry but what is HGB? Link to comment Share on other sites More sharing options...
R1R2 Posted April 22, 2016 Share Posted April 22, 2016 hemoglobin Link to comment Share on other sites More sharing options...
gagpinks Posted April 23, 2016 Author Share Posted April 23, 2016 I knew it you probably mean Hb but there will be variations in in Hb in pre and post sample depending on bleeding. How is it related to Hb? Link to comment Share on other sites More sharing options...
Malcolm Needs ☆ Posted April 23, 2016 Share Posted April 23, 2016 (edited) It is almost certainly due to the immaturity of the ABO antigens. You have to remember that these antigens are carbohydrates and cannot, therefore, be direct gene products. The direct gene products have to be proteins, and in the case of the ABO, H and Lewis antigens (indeed, any antigen that is carbohydrate, rather than protein based) is a transferase enzyme. In the case of the A antigen, the transferase enzyme is alpha-1-3-N-acetyl-D-galactosyltransferase that transfers an N-acetyl-D-galactosamine residue from a uridine donor molecule to the subterminal D-galactose residue of either the type 1 or type 2 backbone molecules. Very often, at birth, the transferase molecule is not working at its full kinetic capacity - which is why you see mixed-field reactions with ABO grouping reagents (and why almost all babies are Le(a-b-)). Edited April 23, 2016 by Malcolm Needs tricore, AuntiS and John Eggington 3 Link to comment Share on other sites More sharing options...
gagpinks Posted April 23, 2016 Author Share Posted April 23, 2016 Thank you Malcolm! ! Link to comment Share on other sites More sharing options...
John Eggington Posted April 23, 2016 Share Posted April 23, 2016 Gestational age also has an impact, I.e., the more premature a baby is the more likely you are to see this phenomenon Malcolm Needs, gagpinks, AMcCord and 2 others 5 Link to comment Share on other sites More sharing options...
Malcolm Needs ☆ Posted April 23, 2016 Share Posted April 23, 2016 24 minutes ago, John Eggington said: Gestational age also has an impact, I.e., the more premature a baby is the more likely you are to see this phenomenon Couldn't agree more John - excellent point! AMcCord, tricore, AuntiS and 1 other 4 Link to comment Share on other sites More sharing options...
crsmith Posted April 25, 2016 Share Posted April 25, 2016 If you had typed the baby's cells with A1 lectin it was probably negative. Some babies will start out A2 and convert to A1 thus giving a mixed field appearance. Yanxia, AMcCord and Malcolm Needs 3 Link to comment Share on other sites More sharing options...
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now