37. Rhesus system. Maternal-foetal immunological conflict.

Question 1

Rhesus factor

Answer 1

-System: Second widely used blood group system.

-Antigens: Six main antigens - C, c, D, d, E, e on erythrocyte surfaces.

-Key Antigen: D antigen determines Rh status.
–D+ (Rh+): Presence of D antigen.
–D- (Rh-): Absence of D antigen.
-Antibodies: No natural antibodies against Rhesus antigens.
-Formation of Antibodies: Can occur due to:
–Incompatible blood transfusion
–Gynecological procedures
–Pregnancy (mother-fetus conflict)

Question 2

Maternal-foetal immunological conflict

Answer 2

Cause: Mother’s blood type is Rh-; fetus’ blood type is Rh+.

Mechanism: Fetal red cells enter maternal circulation, causing mother to produce antibodies against D antigen.

Effects on Fetus:
-Hemolytic Disease: Antibodies cross placenta, damaging fetal red cells.
-Severe Cases: Can cause fetal death in utero.
-Neonatal Period: Severe anemia and jaundice, potentially fatal.

Damage: Affects central nervous system and other organs.