Hemolytic Disease of Newborn - 1
Mechanism:
Rh(D)
negative woman formed anti-D through prior exposure
to Rh(D) positive red cells.
Anti-D
antibodies (IgG type) cross placenta and attach to
Rh(D) red cells of fetus
Anti-D
coated red cells of fetus removed by macrophages in spleen of fetus
Clinical
features:
Hydrops
fetalis:
Hemolyzed
red cells cause hepatocellular damage and hepatic obstruction
20 –
25% die in utero
Rest
die shortly after birth
Only
2% of HDN now due to Rh incompatibility