Erythroblastosis fatalis
From Wikipedia, the free encyclopedia
 |
It has been suggested that this article or section be merged into Hemolytic disease of the newborn. (Discuss) |
Contents |
[edit] Erythroblastosis Fatalis
Erythroblastosis fatalis is a condition in which Rh-Sensitization causes death of the unborn foetis due to antibody complications.
[edit] Cause
During pregnancy, the mother's antibodies cross the placental barrier and enter the blood of the fetus. If the mother is Rh-negative and has been Rh-sensitized through exposure to Rh-positive blood, she has antibodies to the Rh factor. If her baby is Rh-positive, the mother's antibodies attack the fetus' RBCs, and the baby is born with a disease called "hemolytic disease of the newborn" (or HDN), or erythroblastosis fatalis.
The symptoms of HDN result from a low RBC count. With fewer RBCs, the infant's blood has a lowered ability to carry oxygen to the body. The newborn's body tries to compensate for its anemic condition and tries to produce a large number of RBCs in a short amount of time, creating other problems in the body, especially the liver. The liver becomes overworked in trying to keep up with the production of new RBCs and the cleaning away of the dead blood cells. It becomes enlarged and unable to keep up. The dead blood cells form bilirubin and result in jaundice. Fluid also begins to accumulate in the stomach, lungs, and around the heart, giving the baby a swollen look. HDN may be fatal in the most severe cases. All of these symptoms are a direct result of the mother's antibodies attacking the infant's red blood cells.
[edit] Prevention
Preventing Rh sensitization, and thus preventing HDN, is a part of routine prenatal care. Sensitization can be prevented by giving the Rh-negative woman an injection of Rh Immune Globulin (RhIg), such as Rhophylac®, at the twenty-eighth week of pregnancy and another 72-hours after delivery. An RhIg preparation is also given after any possible exposure to Rh-positive blood.
Exposure to Rh-positive blood can occur not only through incompatible transfusions, but also through carrying an Rh-positive baby. Blood may mix in the course of pregnancy during delivery, miscarriage, abortion, Ectopic (or tubal) pregnancy, amniocentesis, abdominal trauma, external manipulation of the uterus such as trying to turn a breech baby, or even across the placenta. In any pregnancy in which an Rh-negative woman carries an Rh-positive baby, there is a risk of Rh exposure and sensitization. If the father is known to be Rh-negative, there is no danger of HDN or Rh sensitization because the fetus will also be Rh-negative.
[edit] Post pregnancy
There is little risk of a woman becoming Rh-sensitized and then affecting her fetus during her first pregnancy. RhIg injections are given after each delivery to protect future pregnancies. The RhIg works to clear away any antigenic cells that may have entered the mother's body, preventing antibody-formation.
Standard prenatal care involves the testing of a woman's blood for Rh antibodies. If she is found to be Rh-sensitized already, no RhIg will be administered because it will not have any effect. Upon delivery, the baby will be watched closely for symptoms of HDN and will be treated accordingly
