Hemolytic disease of the newborn (HDN) is a condition that occurs when the mother’s blood type is not compatible with the baby’s. It occurs in one for every thousand live births.
What is hemolytic disease of the newborn (HDN)?
It is a disease in which the baby’s red blood cells, also called erythrocytes, are destroyed by the mother’s antibodies, causing degradation or hemolysis. It is also known as Erythroblastosis fetalis, Erythroblastosis neonatal, or Rh incompatibility .
How is it detected?
Normally, it is detected in pregnancy. All pregnant women, at the first prenatal visit, undergo a blood test to determine if they are Rh positive or Rh negative and are screened for antibodies using the indirect Coombs test.
When the mother is Rh negative, her immune system sees the baby’s Rh positive red blood cells as foreign and responds by making antibodies to fight and destroy them.
As prevention, all Rh-negative mothers are screened for anti-erythrocyte antibodies during pregnancy (at 28 weeks) and again at delivery.
If Rh antibodies are not detected at 28 weeks, the pregnant woman is given an injection of Rh-type immunoglobulin (Rh-Ig) in order to eliminate any trace of Rh-positive fetal red blood cells from her circulation, thus preventing the development of Rh-type antibodies from the mother.
At birth, the newborn’s Rh system is determined. If the baby is Rh negative, the mother will not require any further Rh-Ig injections; If the baby is Rh positive and the mother does not have antibodies to the D antigen, Rh-Ig will be given within 72 hours after delivery to prevent the mother from making antibodies.
Why does the disease occur?
If the blood of the mother and the baby mix at some point, it is a problem that the baby’s red blood cells pass to the mother and her immune system tries to destroy them.
It is something that can happen during childbirth but also if there is a miscarriage, a fall or a prenatal test, such as an amniocentesis or a chorionic biopsy. In these tests, a needle is used to take a sample of tissue and bleeding may occur.
Normally, Rh sensitization is not a problem in a first pregnancy, but after the first delivery the mother generates antibodies and the problems occur in future pregnancies with another Rh positive baby.
Symptoms of hemolytic disease in the baby
During pregnancy, the mother does not have any symptoms, but through prenatal tests it can be observed:
- Yellowish amniotic fluid.
- That the baby has an enlarged liver, spleen or heart.
- The baby has extra fluid in his stomach, lungs, or scalp.
After delivery, newborns with hemolytic disease may have:
- Swelling
- Paleness, due to having few red blood cells (anemia)
- Yellowing (jaundice) that may appear within 24 to 36 hours after birth.
- Enlarged liver or spleen
- Fluid buildup in your stomach, lungs, or scalp (hydrops fetalis).
Treatment of hemolytic disease
The AEP estimates that in 40 percent of cases no treatment is required , 10 percent need intrauterine transfusions, another 10 percent IUT and early delivery. Another 10 percent need early delivery and subsequent exchange transfusions, and the remaining 30 percent reach the end of pregnancy but will need postnatal treatment.
- Treatment during pregnancy:
The mother should be monitored regularly to control the baby’s blood flow from 15 weeks of gestation.
Depending on the severity, if necessary, an intrauterine transfusion will be performed to place red blood cells in the baby’s circulation. The test involves inserting a needle through the uterus into the baby’s abdominal cavity and into a vein in the umbilical cord.
- Treatment after birth:
If the baby is jaundiced, he or she will undergo phototherapy , a therapy that involves placing the baby under a special light to get rid of excess bilirubin.
Depending on the severity of the disease, blood transfusions will be considered for the baby if he has severe anemia. It may also be necessary to perform an exchange transfusion , a test in which the baby’s blood with a high bilirubin level is removed and replaced with new blood with a normal bilirubin level, or intravenous immunoglobulin , a solution containing antibodies to help to the baby’s immune system.
Can it be prevented?
The prevention of the disease consists in that all non-sensitized Rh-negative mothers should receive prophylaxis in the 28th week of gestation and in the first 72 hours after delivery .
Also after an abortion, molar pregnancy, amniocentesis, chorionic biopsy and any other intrauterine procedure.
With a correct prevention policy, only one awareness can be reached for every 10,000 women.
In Babies and more | The most frequent diseases in the newborn and warning signs that we must watch out for
