DL-995: Hemolytic Disease of the Newborn, 1 CE

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 CAMLT is approved by the California Department of Public Health as a CA CLS Accrediting Agency (#21) 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.