Download Rh(D) Alloimmunization

Rh(D) Alloimmunization
Prevention of Rh(D) alloimmunization in
pregnancy
• Rh(D)-negative pregnant women
• Exposed to fetal D-positive red cells are at risk for developing anti-D
antibodies.
• Widespread use of anti-D immunoglobulin has dramatically reduced, but not
eliminated, D alloimmunization.
www.uptodate.com/MusePath/contents/prevention-of-rhesus-d-alloimmunization-in-pregnancy?source=search_result&search=Rh(D)%20alloimmunization&selectedTitle=3~150
Prevention of Rh(D) alloimmunization in
pregnancy
• Hemolytic disease of the fetus and newborn
• Severe form of anemia caused by the production of maternal antibodies
against fetal red blood cells.
• Rhesus D (RhD), ABO, and less commonly other blood group antigen
incompatibility between the fetus/infant and the mother can lead to the
production of maternal antibodies (alloimmunization) when there is
fetomaternal hemorrhage
www.uptodate.com/MusePath/contents/prevention-of-rhesus-d-alloimmunization-in-pregnancy?source=search_result&search=Rh(D)%20alloimmunization&selectedTitle=3~150
Evaluation
• Screening
• Blood antigen typing for ABO and Rhesus D (RhD) groups and maternal Rh
antibody
• At the first prenatal visit.
• First-time alloimmunized pregnancies
• Monitor every 4 weeks
• Increased risk for hemolytic anemia.
• Pregnancies in women that were previously Rh alloimmunized
• Increase the risk for hemolytic anemia in the infant.
http://www.dynamed.com/topics/dmp~AN~T114634/Hemolytic-disease-of-the-fetus-and-newborn-HDFN
Management
• Pregnant Rh-negative women with
• a negative maternal Rh antibody screening result,
• indicating no prior anti-D alloimmunization,
• should have a repeat screening at 28 weeks to assess for alloimmunization
• if it is negative should receive 300 mcg Rh immune globulin intramuscularly, with
consideration of a second dose if the fetus has not delivered by 40 weeks gestation
• positive maternal Rh antibody screening result,
• indicating an RhD sensitized pregnancy, require determination of maternal RhD antibody
titers
http://www.dynamed.com/topics/dmp~AN~T114634/Hemolytic-disease-of-the-fetus-and-newborn-HDFN
Prevention of Rh(D) alloimmunization in
pregnancy
• Rh(D)-negative Pregnants whose fetus is/may Rh(D)-positive:
• Administration of anti-D immunoglobulin early in the third trimester
• 300 micrograms at 28 weeks of gestation
• 100 to 120 micrograms at 28 and 34 weeks
Management
• Management of Rh alloimmunized fetus may include:
• Intrauterine transfusion for fetal hematocrit ≤ 30% before 35 weeks gestation
• Testing for fetal lung maturity and amniotic bilirubin level
• Guide the decision as to when and if labor should be induced
http://www.dynamed.com/topics/dmp~AN~T114634/Hemolytic-disease-of-the-fetus-and-newborn-HDFN
Prevention of Rh(D) alloimmunization in
pregnancy
• Antenatal anti-D immunoglobulin
• 300 micrograms as soon as possible within 72 hours of the event
• Increased risk of fetomaternal hemorrhage
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ectopic pregnancy,
miscarriage,
abortion,
multifetal reduction,
amniocentesis,
chorionic villus sampling,
blunt abdominal trauma,
external cephalic version,
antepartum bleeding, and
fetal death.
Prevention of Rh(D) alloimmunization in
pregnancy
• Ongoing risk for fetomaternal hemorrhage
• Repeat dosing
• chronic placental abruption or placenta previa with intermittent vaginal
bleeding
• Serial determinations of the maternal indirect Coombs every three weeks
with repeat dosing if it is found to be negative.
Prevention of Rh(D) alloimmunization in
pregnancy
• Anti-D immunoglobulin within 72 hours of delivery of an Rh(D)positive infant
• 300 micrograms
• Additional doses
• Excessive fetomaternal hemorrhage
• If inadvertently omitted after delivery
• as soon as possible
• Partial protection is afforded with administration within 13 days of the birth
• May be an effect as late as 28 days after delivery
Prevention of Rh(D) alloimmunization in
pregnancy
• Management of pregnancies complicated by alloimmunization
• intrauterine fetal transfusions
• Investigational
• maternal plasmapheresis
• intravenous immune globulin therapy