Course # DL-995: Hemolytic Disease of the Newborn
by Helen M. Sowers, MA, CLS - Dept. of Biological Science (retired) - California State University, East Bay - Hayward, CA
Approved for 1.0 CE
Level of Difficulty: Basic
In the past Hemolytic Disease of the Newborn (HDN) was a major cause of death and disability in Caucasian fetuses and newborn infants. The condition occurs when an infant has a RBC antigen, inherited from the father, that the mother lacks, and she produces IgG antibodies to this antigen. These antibodies in the mother cross the placenta and cause destruction of red blood cells in the fetus. The infant develops anemia in utero that may lead to hydrops fetalis (severe edema) and other problems. After birth the infant may develop jaundice due to accumulation of bilirubin from continued hemolysis of RBCs.
Formerly the most common cause of HDN was Rh (D) incompatibility. It wasn’t until this blood group antigen was identified in 1940, and then associated with HDN in 1941, that the pathogenesis was described. By the late1960s this led to the use of therapeutic antibodies to prevent sensitization of the Rh-negative mother by the infant’s RBCs. Now all Rh-negative mothers at risk of becoming sensitized are given anti-Rh (D) antibodies during pregnancy and at the time of delivery.
At present the most common cause of HDN is ABO incompatibility, with Rh (D) next. Other blood groups are less frequent causes of HDN.
Laboratory testing plays a crucial role in the identification of at-risk pregnancies, the prophylaxis of HDN, the diagnosis of the disease, and the identification of the antibody causing the problem.
- Summarize the history of Rh-Hemolytic Disease of the Newborn (HDN)
- Outline the model of Rh-HDN
- Explain the cause of ABO-HDN and contrast to Rh-HDN
- State the racial differences in incidence of the Rh negative gene
- Discuss the conditions that affect the sensitization of the mother to the Rh antigen.
- Discuss the symptoms of HDN
- Outline the treatment options for the fetus and newborn with HDN
- List the tests for HDN done on the mother, fetus, and newborn