Hemolytic disease of the new born (HDN)

Hemolytic disease of the new born (HDN)
Hyperbilirubinemia:
Refers to the increased level of accumulated bilirubin in the blood & characterized by jaundice or icterus.

Normally there is balance between the destruction of RBCs and the use or secretion of it’s products
Causes of Hyper bilirubinemia:
physiologic (developmental) factors such as, prematurity
An association with breast-feeding or breast milk
Excess production of bilirubin e.g. hemolytic disease, biochemical defects, and bruises
Disturbed capacity of the liver to secrete conjugated bilirubin, e.g. enzyme deficiency, bile duct obstruction.
Combined over production and under secretion e.g. sepsis
Some disease states e.g. hypothyroidism, galactosemia, and infants of diabetic mothers
Anemia in this condition is caused by the destruction of the RBCs which stimulate the  ? production of +++ RBC leading to more hemolysis.
Hyperbilirubinemia in the first 24hrs after birth result of:
Erythroblastosis fetalis in which there is an abnormally rapid rate of RBCs destruction.

The major cause of erythrocyte destruction is:

Isoimmunization primary Rh & ABO incompatibility
Blood incompatibility
Antibodies in the serum of a blood group will produce agglutination or clumping reaction when mixed with antigens of a different blood group.
The maternal blood type is O and the fetal blood type is A; it may also occur when the fetus has type B or AB blood.