HDFN And Blood Bank Transfusion Exam 2 With
Complete Solution
HDN - ANSWER Destruction of the fetus/ neonates RBCs by Abs produced by the
mother. the father passes on antigens to the baby that are different than the mothers
The mother can be stimulated to form the antibodies by previous pregnancy or
transfusion and sometimes during the second or third trimester.
Factors that affect immunization (5) - ANSWER 1. antigenic exposure
2. host factors
3. immunoglobulin class
4. Antibody specificity
5. Influence of the ABO blood group
antigenic exposure
- how often does transplacental hemorrhaging of fetal RBCs into the maternal
circulation occur? - ANSWER transplacental hemorrhage of fetal RBCs into the maternal
circulation occurs in up to 7% of women during gestation. At delivery, the risk increased
to about 50%
what else can be the cause hemorrhage - ANSWER Test procedures (amniocentesis and
chronic villus sampling) and trauma can also be the cause of hemorrhage.
how many fetal RBCs are needed to stimulate the mother - ANSWER only about 1 mL
Host factors that effect immunization - ANSWER the ability of an individual to produce
antibodies in response to antigen exposure varies. some people will never produce an
Ab even after repeat exposure, where others will produce Abs to everything they are
, exposed to
Immunoglobulin class factors that effect immunization - ANSWER IgG only class that can
cross the placenta
- IgG1 and IgG3 are more efficient in RBC hemolysis than IgG2 and 4
- types of subclasses the mother produces can affect the severity of the hemolysis
hemolysis - ANSWER hemolysis occurs when the maternal AB attaches to the fetal RBC
- the AB coated RBCs are then removed from the circulation by the macrophages of the
spleen
Rate of destruction depends on what - ANSWER rate of destruction depends on titer and
specificity of the antibody and on the number of antigenic sites present on the RBCs
Effects of destruction - ANSWER 1. erythroblastosis fetalis
2. Hepatosplenomegaly
3. hypos fetalis
Erythroblastosis Fetalis - ANSWER When immature RBCs are released into circulation
due to destruction which causes the bone marrow to produce RBCs at an increase rate
hepatosplenomegaly - ANS If the BM cannot keep up with the destruction, RBCs
production must occur outside of the BM in the spleen and liver, this causes
hepatosplenomegaly, resulting in total hypertension and hepatocellular damage
Hydrops fetalis - ANS condition caused by severe anemia and hyperproteinemia. See
cardiac failure, effusions, and ascites
Billirubins effe ect in HDN - ANSWER Bilirubin levels may be high in fetus and amnionic
fluid and may not cause a problem. After baby is born they are unable to conjugate the
bilirubin effectively. If left untreated can cause kernicterus (permanent brain damage)
Complete Solution
HDN - ANSWER Destruction of the fetus/ neonates RBCs by Abs produced by the
mother. the father passes on antigens to the baby that are different than the mothers
The mother can be stimulated to form the antibodies by previous pregnancy or
transfusion and sometimes during the second or third trimester.
Factors that affect immunization (5) - ANSWER 1. antigenic exposure
2. host factors
3. immunoglobulin class
4. Antibody specificity
5. Influence of the ABO blood group
antigenic exposure
- how often does transplacental hemorrhaging of fetal RBCs into the maternal
circulation occur? - ANSWER transplacental hemorrhage of fetal RBCs into the maternal
circulation occurs in up to 7% of women during gestation. At delivery, the risk increased
to about 50%
what else can be the cause hemorrhage - ANSWER Test procedures (amniocentesis and
chronic villus sampling) and trauma can also be the cause of hemorrhage.
how many fetal RBCs are needed to stimulate the mother - ANSWER only about 1 mL
Host factors that effect immunization - ANSWER the ability of an individual to produce
antibodies in response to antigen exposure varies. some people will never produce an
Ab even after repeat exposure, where others will produce Abs to everything they are
, exposed to
Immunoglobulin class factors that effect immunization - ANSWER IgG only class that can
cross the placenta
- IgG1 and IgG3 are more efficient in RBC hemolysis than IgG2 and 4
- types of subclasses the mother produces can affect the severity of the hemolysis
hemolysis - ANSWER hemolysis occurs when the maternal AB attaches to the fetal RBC
- the AB coated RBCs are then removed from the circulation by the macrophages of the
spleen
Rate of destruction depends on what - ANSWER rate of destruction depends on titer and
specificity of the antibody and on the number of antigenic sites present on the RBCs
Effects of destruction - ANSWER 1. erythroblastosis fetalis
2. Hepatosplenomegaly
3. hypos fetalis
Erythroblastosis Fetalis - ANSWER When immature RBCs are released into circulation
due to destruction which causes the bone marrow to produce RBCs at an increase rate
hepatosplenomegaly - ANS If the BM cannot keep up with the destruction, RBCs
production must occur outside of the BM in the spleen and liver, this causes
hepatosplenomegaly, resulting in total hypertension and hepatocellular damage
Hydrops fetalis - ANS condition caused by severe anemia and hyperproteinemia. See
cardiac failure, effusions, and ascites
Billirubins effe ect in HDN - ANSWER Bilirubin levels may be high in fetus and amnionic
fluid and may not cause a problem. After baby is born they are unable to conjugate the
bilirubin effectively. If left untreated can cause kernicterus (permanent brain damage)
