lectue 4.docx

2 Pages
Unlock Document

Biochem. and Medical Genetics
BGEN 3020
Jason Leboe- Mcgowan

Lecture 4 blood types ABO/Rh incompatibility ABO incompatibility: If blood group O woman have a baby, the mom will have a problem with ABO incompatibility b/c mom already have an Ab that can cross the placenta (blood group O people have anti A IgM, anti B IgM and anti AB IgG, normally). Normally, there is an anti AB IgG Ab which can cross the placenta, and attack an A or B RBC. So, there could be a problem in the very first pregnancy. Example: mom is blood group O negative and baby is blood group A negative. Is there an incompatibility of blood groups? Yes. Is there an incompatibility in Rh groups? No. Just the blood groups, since the mom is O while baby is A. The mom is O, she has anti AB IgG, which will cross the placenta; the A part of the Ab will attach to the A part of the A cells of the baby’s. The baby’s macrophages of the spleen will destroy it, which is Type II HPY, mild anemia, and unconjugated bilirubin which is handled by the mom’s liver; no kernicterus, no probs with jaundice in the baby b/c in utero, the mom’s liver will take care of it. When the baby is born the baby, it will have a mild anemia and jaundice. MCC jaundice in the first 24 hrs for a newborn = ABO incompatibility (not physiologic jaundice of the newborn – that starts on day 3). Why did the baby develop jaundice? B/c the baby’s liver cannot conjugate bilirubin yet and must handle unconjugated bilirubin on its own now, so it builds up. This is an exchange transfusion rxn for ABO incompatibility – most of the time is b9, and put under UV B light. How does UV B light work? It converts the bilirubin in the skin into di-pyrol, which is water soluble and they pee it out (Rx for jaundice in newborn). Anemia is mild b/c it is not a strong Ag and doesn’t holster a brisk hemolytic anemia. If you do a coomb’s test, it will be positive b/c IgG’s on the RBC’s. So always an O mom with a blood group A or AB baby. This can occur from the first pregnancy (not like Rh sensitization where the first pregnancy is not a problem). In any pregnancy, if mom is blood group O, and she has a baby with blood group A or B, there will be a problem (blood group O = no problem). Rh incompatibility Mom is Rh negative and baby is Rh positive. Example: mom is O negative and baby is O positive (not ABO incompatible, but Rh incompatible). In the first pregnancy: deliver baby without going to a Dr, and there is a fetal maternal bleed, some of the babies O positive Ab’s got into my bloodstream, which is not good. So, mom will develop an anti B Ab against it. So, mom is sensitized which means that there is an Ab against that D Ag and now mom is anti D. 1 year later, mom is pregnant again, and still O negative, and have anti D and the baby again is O positive. This is a problem b/c it is an IgG Ab, which
More Less

Related notes for BGEN 3020

Log In


Join OneClass

Access over 10 million pages of study
documents for 1.3 million courses.

Sign up

Join to view


By registering, I agree to the Terms and Privacy Policies
Already have an account?
Just a few more details

So we can recommend you notes for your school.

Reset Password

Please enter below the email address you registered with and we will send you a link to reset your password.

Add your courses

Get notes from the top students in your class.