What is Erythroblastosis Fetalis?
Erythroblastosis Fetalis is a pathological condition in which the red blood cells of the fetus are destroyed by the IgG antibodies of the mother. This process of the development of antibodies in the mother is termed as isoimmunization. The antibodies develop when the erythrocytes of the fetus which have certain RBC antigens come in contact with the blood of the mother. This results in the immune system of the mother producing antibodies to combat these fetal antigens and destroy them. This is what results in Erythroblastosis Fetalis[1].
How severe the disease is depends on the strength of the antibodies that are produced by the mother’s immune system along with the age of the fetus and how capable the fetus is to fill the void caused by the destroyed RBCs. Rh factor which is a component of the blood and is not present in everyone plays a crucial role in determining whether a child may develop Erythroblastosis Fetalis[1].
The likelihood of a fetus developing Erythroblastosis Fetalis increases if the mother is Rh negative meaning there is no Rh factor present in the blood and the fetus is Rh positive meaning there is Rh factor present in the unborn baby. This happens because the blood of the mother and the fetus is incompatible. This article gives a brief overview of some of the causes of Erythroblastosis Fetalis and different treatment options available for it[1].
What Causes Erythroblastosis Fetalis?
Erythroblastosis Fetalis occurs if the mother is Rh negative and the fetus is Rh positive, even though it may be minimal. It is quite rare but sometimes the blood of the fetus and the mother get mixed. This also becomes one of the causes for Erythroblastosis Fetalis. This may happen due to the placenta getting detached from the wall of the uterus at the time of delivery of the child. It can also occur in cases where there is bleeding during pregnancy. If for some reason there is rotation of the fetus within the womb or the baby is in a breech presentation then also there is a likelihood of the fetus developing Erythroblastosis Fetalis[2].
Females with a previous history of miscarriages or abortion also are at high risk for delivering a baby with Erythroblastosis Fetalis. Rh sensitization is also one of the primary causes of Erythroblastosis Fetalis. This process occurs when the blood of the Rh positive mother gets mixed with blood of an Rh negative fetus. When this happens, the immune system of the mother produces antibodies to attack the Rh negative blood which it takes as invaders. This means that any future pregnancies where the fetus has Rh negative blood will also be at risk for Erythroblastosis Fetalis[2].
The red blood cells in the fetus tend to get destroyed by the immune system of the mother quite rapidly. This results in the fetus being deprived of enough oxygen supply causing conditions like anemia after birth. At times, the destruction of the red blood cells is so rapid and quick that the fetus is not able to survive it leading to stillbirths. Even though the fetus tries to replenish the red blood cells lost, these new cells are not mature enough to function the way they should[2]
Since the red blood cells are produced in the liver and spleen, when the fetus tries to produce excessive red blood cells then it may lead to enlargement of the liver and spleen as well. The new red blood cells produced by the fetus continue to break down, bilirubin starts to accumulate. Bilirubin is a product obtained during breakdown of the red blood cells. Excess of bilirubin is the primary cause for jaundice which if severe can be potentially fatal for the baby[2]
Coming to risk factors, studies suggest that white infants are more likely to develop Erythroblastosis Fetalis than African-American babies. It should be noted here that mothers and babies can have different blood types and should not be a cause of concern unless their bloods mix with each other. It is then that Erythroblastosis Fetalis develops[2].
This condition may not be so prominent in the first pregnancy of a female but definitely may affect any future pregnancies especially in cases where Rh sensitization has occurred[2].
How is Erythroblastosis Fetalis Treated?
Fetal blood transfusion is the primary mode of treatment for Erythroblastosis Fetalis. This is followed by delivery of the fetus between the 32nd and 37th week of pregnancy. If a child is born with Erythroblastosis Fetalis, then the treatment options include immediate blood transfusions. This is followed by intravenous fluid administration. If the baby has difficulties in breathing normally then that will also be addressed[2].
Some babies are also given IVIG or intravenous immunoglobulin therapy. The aim of this therapy is to manage the breakdown of red blood cells and accumulation of bilirubin to prevent jaundice[2].
Sometimes, an exchange transfusion is necessary. Another mode of treatment for newborns with Erythroblastosis Fetalis is exchange transfusion. In this form of transfusion, the baby’s blood is transfused with a donor’s blood simultaneously. This is done to increase fully functional red blood cells and prevent the collection of bilirubin[2].
In conclusion, Erythroblastosis Fetalis is quite a serious medical condition that begins when the fetus is in the developing phase. The primary cause of this condition is the incompatibility between the Rh factor of the mother and the fetus. Erythroblastosis Fetalis can result in severe complications like anemia, jaundice, and at times even heart failure[2].
IVIG, exchange transfusion, and fetal blood transfusion are some of the modes of treatment for Erythroblastosis Fetalis. If a female is at risk for the fetus developing Erythroblastosis Fetalis in future pregnancies then Rh immunoglobulin is a treatment option available that may prevent mixing of Rh positive blood of the mother with Rh negative blood of the fetus thereby preventing the development of Erythroblastosis Fetalis[2].
