Fetal Hydrops (10)

Question 1

What is Fetal Hydrops?

Answer 1

Accumulation of edema fluid in fetus during intrauterine growth

Question 2

Accumulation of edema fluid in fetus during intrauterine growth

Answer 2

Fetal Hydrops

Question 3

What are the 2 types of fetal hydrops?

Answer 3

1. Immune

2. Nonimmune

Question 4

What is the current most common form of hydrops and why?

Answer 4

Nonimmune due to successful prophylaxis

Question 5

What is Immune Hydrops?

Answer 5

Hemolytic disease cause by blood group antigen incompatibility between the mother and fetus!

Question 6

What pregnancy does immune hydrops affect?

Answer 6

2nd!

Question 7

Describe the setup for immune fetal hydrops to occur

Answer 7

Rh - mother and Rh + father

= Rh + 1st child

Question 8

When will the mother become sensitized to the Rh + antigen?

Answer 8

During her first pregnancy with an Rh + child, at the last trimester

Question 9

How does Rh + fetal blood reach maternal circulation at the last trimester?

Answer 9

Due to loss of cytotrophoblast barrier or during birth iteself

Question 10

What is the most common Rh + antigen that causes incompatibility?

Answer 10

D

Question 11

During the first pregnancy, when fetal Rh D+ blood reaches maternal circulation of Rh - , what antibodies will be made?

Answer 11

IgM - cannot cross placenta

Question 12

When the mother becomes sensitized, what antibodies does she produce and why is the first child not affected?

Answer 12

IgM antibodies cannot cross the placenta

Question 13

When the second child is Rh D+, what antibodies will become active?

Answer 13

IgG! - can cross placenta

Question 14

With the second child, how does hemolytic disease begin?

Answer 14

If the fetal blood crosses into maternal circulation, the IgG antibodies will cross the placenta and degrade the fetal RBCs

Question 15

Greater than ___ ml of fetal Rh + blood into maternal circulation will cause an antibody response

Answer 15

1 mL

Question 16

The mother’s antibody response depends on the dose of the antigen that reaches her blood stream. How much will need to cross?

Answer 16

1 mL

Question 17

Once IgG antibodies attach and begin to degrade the fetal RBCs, describe what happens as anemia progresses.

Answer 17

• Anemia
• Causes liver injury and cardiac decompensation
• Liver injury results in decreased albumin synthesis
• Decreased albumin synthesis causes decreased oncotic pressure = edema
• Cardiac decompensation = edema
  == Fetal hydrops

Question 18

Once IgG antibodies attach and begin to degrade the fetal RBCs, describe what happens are hemoglobin is degraded.

Answer 18

• Hb is degraded and releases heme
• Heme is converted to bilirubin
• Increased levels of bilirubin
• Bilirubin deposits in the basal ganglia of the brain
  = Jaundice and Kernicterus

Question 19

A level of bilirubin in the blood greater than ___ will usually cause kernicterus

Answer 19

20

Question 20

Where does bilirubin get deposited in the brain for kernicterus to occur?

Answer 20

Basal ganglia

Question 21

What treatment is given to the Rh - mother now?

Answer 21

Rhesus Immune Globin with Anti - D antibodies (RhIg)

Question 22

When is Rhesus Immune Globin with anti - D antibodies given to the Rh - mother?

Answer 22

28 weeks gestation and within 72 hours of birth of the child

Question 23

Is RhIg also given after abortions?

Answer 23

Yes

Question 24

3 causes of nonimmune hydrops?

Answer 24

1. Cardiovascular
2. Chromosomal anomalies
3. Fetal anemia

Question 25

What cardiovascular defects can cause nonimmune hydrops?

Answer 25

Malformations and arrhythmias

Question 26

What chromosomal anomalies can cause nonimmune hydrops?

Answer 26

Turner's syndrome (45X), Trisomy 18 and 21

Question 27

How do chromosomal anomalies like Trisomy 18 and 21 cause nonimmune hydrops?

Answer 27

They have associated cardiac abnormalities

Question 28

What is the most common cause of fetal anemia that can cause nonimmune hydrops?

Answer 28

Homozygous alpha-thalessemia

Question 29

What does Homozygous alpha-thalessemia do?

Answer 29

Deletes all 4 alpha globin chains = fetal anemia

Question 30

What virus can cause fetal anemia that results in nonimmune fetal hydrops?

Answer 30

Transplacental infection by Parvovirus B19

Question 31

Describe how Parvovirus B19 causes fetal anemia and thus nonimmune hydrops

Answer 31

- Parvovirus B19 gains entry into normoblasts - The virus replicates = RBC apoptosis and aplasia

Question 32

In nonimmune hydrops associated with fetal anemia, what color are the fetus and placenta?

Answer 32

PALE

Question 33

In nonimmune hydrops associated with fetal anemia, describe the bone marrow.

Answer 33

Bone marrow exhibits compensatory hyperplasia of erythroid precursors

Question 34

In nonimmune hydrops associated with fetal anemia, describe what is seen in other places?

Answer 34

Extramedullary hematopoiesis is present in other tissues!

Question 35

How do RBCs look in nonimmune hydrops due to fetal anemia?

Answer 35

LARGE number of IMMATURE RBCs | -- reticulocytes and erythroblasts

Question 36

A large number of reticulocytes and erythroblasts is known as?

Answer 36

Erythroblastosis Fetalis

Question 37

Erythroblastosis Fetalis

Answer 37

Large number of immature RBCs due to Fetal anemia c

Question 38

Turner's syndrome (45X) is susceptible to what type of fluid accumulation?

Answer 38

Postnuchal fluid = cystic hygroma

Question 39

Cystic Hygroma

Answer 39

Postnuchal fluid accumulation seen with turner's syndrome of hydrops

Question 40

Once the IgG antibodies reach fetal blood and begin degrading, describe what results after anemia.

Answer 40

- Anemia - Liver injury (hypoxia) and cardiac decompensation - Liver injury causes decreased synthesis of albumin - Decreased albumin causes decreased oncotic pressure = Edema = Hydrops

Question 41

Once the IgG antibodies reach fetal blood and begin degrading, describe what results with hemoglobin degradation.

Answer 41

- Hemoglobin is degraded to heme - Heme is degraded to bilirubin - Bilirubin levels greater than 20 accumulate in the brain (basal ganglia) and tissues = Jaundice and Kernicterus