Hemolytic Disease of the Fetus and Newborn (F) Flashcards
What is hemolytic disease of the newborn (HDN)?
It is an alloimmune condition that develops in a fetus
When does HDN occur?
When the IgG molecules produced by the mother are passed through the placenta
When the mother does not have the Rh factor present in her blood, but the fetus has this factor
Among the IgG produced by the mother, what is the action of some of these Abs?
They attack the RBCs in the fetal circulation
What happens in HDN?
The RBCs are broken down
What are the results of hemolysis of fetal RBCs?
1) Reticulocytosis
2) Anemia
What is the range in terms of severity of HDN that can occur?
From mild to very severe, and fetal death
What is the cause of fetal death?
Heart failure
What are present in the fetal blood if HDN is moderate or severe?
Many erythroblasts
What is erythroblastosis fetalis?
It is the form of HDN (specifically the moderate / severe ones) whereas many erythroblasts are present
What is the other name of erythroblastosis fetalis?
Erythroblastosis foetalis
When does HDN occur (explain its principle / mechanism)?
It occurs when the fetus has a blood grp Ag that the mother does not possess. Whereas the mother’s body forms an Ab against that particular blood grp Ag, and hemolysis begins
The process of Ab formation is called as what?
Maternal sensitization
Why does the fetus (w/ HDN) acquired anemia?
Due to the hemolysis of RBCs
Due to the anemia of the fetus, what does the body of fetus do?
It compensates by producing large #s of immature erythrocytes (w/c are reticulocytes)
What are the other names of HDN?
1) Erythroblastosis fetalis
2) Hydrops fetalis
What is hydrops?
It refers to the edema
What is fetalis?
It refers to the lethal state of the infant
If HDN is present due to Rh incompatibility, hemolysis usually begins where?
In utero
Does HDN (due to Rh incompatibility) affect the 1st pregnancy of the mother?
The 1st pregnancy may not be affected
What are the pregnancies that will be affected by HDN?
The succeeding pregnancies of the mother
If the HDN present is due to ABO incompatibility, when does hemolysis usually begin?
The hemolysis does not usually begin until the birth of the newborn
What is the blood grp Ag present in the fetus?
Rh Ag (specifically D Ag)
Aside from Rh incompatibility, what is the other cause of hemolytic disease?
ABO incompatibility
What is the blood type of the mother and the blood types of the fetus present in most cases of HDN (due to ABO incompatibility)?
Mother: type O
Fetus: either type A, B, or worst is AB
What is the principle of HDN (due to ABO incompatibility) in relation to difference in blood type between mother and fetus? Provide / explain each context
Mother: type O
Fetus: type A
-> the anti-A of the mother will attack the A Ag of the fetus
Mother: type O
Fetus: type B
-> the anti-B of the mother will attack the B Ag of the fetus
Mother: type O
Fetus: type AB
-> the anti-A and anti-B of mother will attack the A and B Ags of fetus, hence, this case is worst than the other 2
Hemolysis in HDN is occasionally caused by what?
Maternal anemias (such as thalassemia or from other blood grp Ags [anti-D])
What is 1 of the signs of HDN?
Hemolysis (w/c leads to elevated bili lvls), hence, the neonate has jaundice
What is jaundice?
It is the condition whereas the pt is characterized as having symptoms such as yellowish skin and yellow discoloration of the whites of the eyes (/ sclera of the eyes)