Hemolytic Disease of the Newborn

Only available on StudyMode
  • Download(s) : 181
  • Published : November 27, 2012
Open Document
Text Preview
Hemolytic Disease of the Newborn
-------------------------------------------------
What is hemolytic disease of the newborn (HDN)?
Hemolytic disease of the newborn is also called erythroblastosis fetalis. This condition occurs when there is an incompatibility between the blood types of the mother and baby. * "Hemolytic" means breaking down of red blood cells

* "Erythroblastosis" refers to making of immature red blood cells * "Fetalis" refers to fetus
-------------------------------------------------
What causes hemolytic disease of the newborn (HDN)?
HDN most frequently occurs when an Rh negative mother has a baby with an Rh positive father. When the baby's Rh factor is positive, like the father's, problems can develop if the baby's red blood cells cross to the Rh negative mother. This usually happens at delivery when the placenta detaches. However, it may also happen anytime blood cells of the two circulations mix, such as during a miscarriage or abortion, with a fall, or during an invasive prenatal testing procedure (e.g., an amniocentesis or chorionic villus sampling). The mother's immune system sees the baby's Rh positive red blood cells as "foreign." Just as when bacteria invade the body, the immune system responds by developing antibodies to fight and destroy these foreign cells. The mother's immune system then keeps the antibodies in case the foreign cells appear again, even in a future pregnancy. The mother is now "Rh sensitized." In a first pregnancy, Rh sensitization is not likely. Usually, it only becomes a problem in a future pregnancy with another Rh positive baby. During that pregnancy, the mother's antibodies cross the placenta to fight the Rh positive cells in the baby's body. As the antibodies destroy the red blood cells, the baby can become sick. This is called erythroblastosis fetalis during pregnancy. In the newborn, the condition is called hemolytic disease of the newborn. -------------------------------------------------

Who is affected by hemolytic disease of the newborn?
Babies affected by HDN are usually in a mother's second or higher pregnancy, after she has become sensitized with a first baby. HDN due to Rh incompatibility is about three times more likely in Caucasian babies than African-American babies. -------------------------------------------------

Why is hemolytic disease of the newborn a concern?
When the mother's antibodies attack the red blood cells, they are broken down and destroyed (hemolysis). This makes the baby anemic. Anemia is dangerous because it limits the ability of the blood to carry oxygen to the baby's organs and tissues. As a result: * The baby's body responds to the hemolysis by trying to make more red blood cells very quickly in the bone marrow and the liver and spleen. This causes these organs to get bigger. The new red blood cells, called erythroblasts, are often immature and are not able to do the work of mature red blood cells. * As the red blood cells break down, a substance called bilirubin is formed. Babies are not easily able to get rid of the bilirubin and it can build up in the blood and other tissues and fluids of the baby's body. This is called hyperbilirubinemia. Because bilirubin has a pigment or coloring, it causes a yellowing of the baby's skin and tissues. This is called jaundice. Complications of hemolytic disease of the newborn can range from mild to severe. The following are some of the problems that can result: During pregnancy:

* Mild anemia, hyperbilirubinemia, and jaundice 
The placenta helps rid some of the bilirubin, but not all.
* Severe anemia with enlargement of the liver and spleen  When these organs and the bone marrow cannot compensate for the fast destruction of red blood cells, severe anemia results and other organs are affected. * Hydrops fetalis 

This occurs as the baby's organs are unable to handle the anemia. The heart begins to fail and large amounts of fluid build up in the baby's tissues and...
tracking img