The human body contains trillions of red blood cells which are also known as erythrocytes. These blood cells are responsible for carrying iron, oxygen, and other kinds of nutrients to different areas in the body where they are appropriately belong.
If a woman is pregnant, there is always a possibility to encounter such a blood type problem which is compatible with her own. This could result to a condition called erythroblastosis fetalis.
Erythroblastosis fetalis is also known as hemolytic disease of the newborn (HDN). It occurs when the blood of the baby combines with the mother’s blood during pregnancy, and the immune system of the mother produces a certain reaction, wherein the white blood cells attack the red blood cells of the baby as they recognize it as foreign invaders.
The white blood cells are the antibodies of the immune system that fight off certain substances and germs that do not belong in the body. When the baby’s red blood cells are attacked by the antibodies, they will eventually break down. These antibodies can cross over to the baby through the placenta before entering the baby’s blood and attacking the erythrocytes.
Erythroblastosis fetalis has two primary causes that are associated with blood type; ABO incompatibility and Rh incompatibility. The body has four blood types: A, B, AB, and O. A human’s blood type can either be Rh negative or Rh positive.
Mechanism and pathogenesis of HDN (erythroblastosis fetalis)
When an individual is type A and Rh positive, they possess A antigens and the Rh factor antigens are found on the surface of the red blood cell membrane. If an individual has AB negative blood type, they possess both A and B antigens without having the Rh factor antigen.
This occurs when a mother is Rh negative, has a baby with an Rh positive father. This could result to an Rh-positive baby wherein the Rh antigens of the baby are seen as foreign invaders. As a result, the mother’s blood cells will attack the baby’s that can cause harm to the child.
This occurs when the blood type of the mother is either A, B, or O and is not compatible with the baby’s. Compared to Rh incompatibility, this condition is contemplated to be less harmful to the baby. Nevertheless, babies could still carry rare antigens that may put them at risk for erythroblastosis fetalis.
Symptoms of Erythroblastosis Fetalis
Symptoms that may occur before the baby is born:
- Swelling of the baby’s body
- Rapid heart rate
- Enlarged organs such as the spleen, liver, or heart
Symptoms that may occur after the baby is born:
- Difficulty breathing
- Jaundice or the yellowish discoloration of the baby’s skin or the whites of the eyes
- Swelling of the baby’s body
- Purple blotches on the baby’s skin
- Small brown or red spots
The precise diagnosis of erythroblastosis fetalis will vary if there is a blood group present or incompatibility of blood type. Before the baby is born, the following tests may be done:
- Ultrasound – This is an imaging test that can produce images of the baby inside the uterus. A Doppler ultrasound could also be used to check the baby’s blood flow. Caregivers might perform this test to evaluate if the baby has anemia.
- Amniocentesis – This test is used of checking problems in the mother’s amniotic fluid such as increased bilirubin level. A sample of the amniotic fluid will be taken which will be sent to the laboratory for evaluation. This test can be done over again to monitor the baby’s risk of anemia.
- Fetal blood sampling – This test is used for checking the baby’s risk of anemia and blood type. A blood sample is taken from the baby’s umbilical cord which will be studied inside the laboratory.
Treatment for erythroblastosis fetalis may include:
Preterm delivery – In some cases, the mother may need a preterm labor wherein the baby is born earlier than expected.
Blood transfusions – Some babies may need blood transfusions given through the umbilical cord.
Treatment for erythroblastosis may include:
Exchange transfusion – A method that involves the removal of some bilirubin and those antibodies that are attacking the baby’s erythrocytes.
Phototherapy – A treatment procedure that makes use of light to change bilirubin into a form that the body of the newborn can remove.
Immune globulin – It is given through an IV or IVIG. This medication can help the baby’s erythrocytes from being harmed by the mother’s antibodies. This can help prevent the need for exchange transfusion.
Complications of erythroblastosis fetalis range from mild to severe. These may include the following problems:
- Hydrops fetalis
- Mild anemia
- Severe anemia accompanied with enlargement of the spleen and liver
- Severe jaundice
- Severe hyperbilirubinemia
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