RH - Hemolytic Disease of Newborn

Question 1

IgG that can cross the placenta

Answer 1

Anti D

Question 2

Immunoglobulin class that are only actively transported across the placenta

Answer 2

IgG

Question 3

Fetal RBCs enter the maternal circulation

Answer 3

FETOMATERNAL HEMORRHAGE

Question 4

3 important factors that must be present for HDN to occur:

Answer 4

1. The mother must lack the antigen
2. The fetus must possess the antigen
   a. Father homozygous- 100% HDN
   b. Father heterozygous- 50% HDN
3. the antigen present in fetus must be WELL-DEVELOPED AT BIRTH

Question 5

Cause significant increases in maternal antibody titers that increase severity of HDN

Answer 5

FETOMATERNAL HEMORRHAGE

Question 6

When does the active transport of IgG begins?

Answer 6

2nd trimester until birth

Question 7

Immunoglobulins that are more efficient in RBC hemolysis.

Answer 7

IgG1 and IgG3

Question 8

Most antigenic RBC antigens

Answer 8

D

Question 9

Blood that is transfused to Rh negative females of childbearing potential.

Answer 9

Rh negative

Question 10

Most clinically significant non-Rh antibody to cause HDN.

Answer 10

Anti-Kell

Question 11

When the mother is ABO incompatible with the fetus, the incidence of detectable FETOMATERNAL HEMORRHAGE is _____________.

Answer 11

Decreased

Question 12

Anemia and the appearance of immature RBC’S in the peripheral blood if the fetus.

Answer 12

Erythroblastosis Fetalis

Question 13

Development of high-output CARDIAC FAILURE with generalized edema, effusions, and ascites.
Severe anemia and hyponatremia.

Answer 13

Hydrops Fetalis

Question 14

Greatest threat of fetus in Rh HDN

Answer 14

Cardiac Failure

Question 15

EFFECT OF RH HDN IN POST-PARTUM
- RBC destruction continues with the release of _______________.
- The new born liver is deficient with _______________.
- As the indirect bilirubin is released, it binds to ____________ and cirlated harmlessly.
- However, when the binding capacity of the albumin is exceeded the indirect bilirubin BINDS TO TISSUES which results to ____________.
- In particular, it may bind to the tissues of the CNS and Cause a Permanent and irreversible brain damage called _________.

Answer 15

• INDIRECT BILIRUBIN
• GLUCORONYL TRANSFERASE
• ALBUMIN
• JAUNDICE
• KERNICTERUS

Question 16

SEROLOGIC TEST:
Must be able to detect clinically significant IgG alloantibodies that are reactive at 37C and in the antiglobulin phase.

Answer 16

Antibody Screen
* If nonreactive- REPEAT TESTING
- Ab IDENTIFICATION

Question 17

SEROLOGIC TEST:
The serum is treated with sulfhydryl reagents and then retested with appropriate controls.

Answer 17

Antibody identification
* Cold IgM Ab are ignored
IgM - destroyed by J chain
IgG - remain active

Question 18

Sulfhydryl reagents that can be used in Rh HDN Antibody identification.

Answer 18

Dithiotreitol
2- mercaptoethanol

Question 19

SEROLOGIC TEST:
A specimen of the fathers blood should be obtained and tested for the presence and zygosity of the corresponding antigen.

Answer 19

Paternal Phenotype

Question 20

SEROLOGIC TEST:
Amniotic is tested to determine whether the amniocytes carry the gene for the D antigen.

Answer 20

Amniocyte testing

Question 21

Amniocentesis can be done in how many weeks of gestation.

Answer 21

10-12 weeks

Question 22

SEROLOGIC TEST:
Used to determine the relative concentration of all antibodies capable of crossing the placenta and causing HDN.

Answer 22

Antibody titer
* Critical titer: 16-32

Question 23

An indication of amniocentesis or percutaneous umbilical blood sampling between 18-24 weeks gestation.

Answer 23

Constant titer of 32 or above

Question 24

Insertion of a needle through the mothers abdominal wall and uterus and extraction of fluid from the amniotic sac.

Answer 24

Amniocentesis

Question 25

Analyte tested in amniocentesis

Answer 25

BILIRUBIN

Question 26

Mild or no disease , which do not require intervention in optical density of liley graph according to gestational age.

Answer 26

Zone 1

Question 27

Liley graph OD:Moderate disease that may require intervention.

Answer 27

Zone 2

Question 28

Liley graph OD: Severe and life threatening hemolysis and require urgent intervention.

Answer 28

Zone 3

Question 29

Process of obtaining fetal blood using ultrasound guided needle in the umbilical vein near the pont of placental insertion.

Answer 29

Cordocentesis/ Percutaneous Umbilical Cord Sampling

Question 30

Cordocentesis is used for what tests?

Answer 30

DAT Hgb Hct Bilirubin ABO and Rh typing Ag phenotype and genotype

Question 31

Serologic test that indicates direction of blood flow

Answer 31

COLOR DOPPLER MIDDLE CEREBRAL ARTERY PEAK CYSTOLIC VELOCITY Red- arterial blood Blue- venous blood

Question 32

What intervention is needed when amniotic fluid change in OD 450 nm results are in high zone 2 or in zone 3, cordocentesis blood has <10g/gL Hgb, and fetalhyrops is present?

Answer 32

Intrauterine transfusion

Question 33

Performed intraperitoneally by injecting the rbc's into fetal peritoneal cavity where the rbc's can be absorbed into the circulation.

Answer 33

Intrauterine transfusion

Question 34

Ultimate goal of intrauterine transfusion?

Answer 34

Maintain fetalhemoglobin above 10g/dL

Question 35

Blood to be transfused in child using uterine transfusion should be:

Answer 35

Group O, D negative Less than 7 days old Hct: 70% (75-80%) Irradiated CMV negative HbS negative Crossmatch compatible with maternal serum

Question 36

After delivery, it used to change unconjugated bilirubin to conjugated bilirubin with ultraviolet light?

Answer 36

Phototherapy

Question 37

In infants with mild-to-modrrate hemolysis, the used of ______________ may avoid the need for exchange transfusion to treat hyperbilirubinemia and anemia.

Answer 37

PHOTOTHERAPY

Question 38

What needs to be done when you have a BLOCKED RH that causes Rh- negative Rh type in infants RBC to reveal anti-D?

Answer 38

Do ELUTION: An eluate from these Rbc's will reveal anti-D, and typing of the eluate Rbc's show reaction with anti-D.

Question 39

The most important serologic test for diagnosis of HDN using anti IgG reagent.

Answer 39

DAT

Question 40

Used primarily to remove high levels of unconjugated bilirubin and thus to prevent kernicterus.

Answer 40

Newborn Transfusions

Question 41

NEWBORN TRANSFUSIONS: Blood to be transfused should be...

Answer 41

Group O, D negative Less than 7 days old resuspended in blood type AB fresh frozen plasma Hct: 40-50% Irradiated CMV neg HbS neg Crossmatch compatible with maternal serum

Question 42

This principle has been used to prevent immunization to D antigen by the used of high-titered Ig.

Answer 42

RhIg

Question 43

DOSE of RhIg Antepartum Administration and when to give.

Answer 43

Full dose (300ug) privdes protection up to 15 ml of D + RBC'S GIVEN: at 28th week of gestation ( 3rd trimester)

Question 44

Postpartum administration dose of RhIg and when to give.

Answer 44

Full dose of RhIg GIVEN within 73 hours of delivery If during delivery, a woman experiences FMH exceeding 30ml of D + RBCs, it is essential she receives more than one dose of RhIg

Question 45

IN postpartum administration, sample should be obtained within hour many hours to test massive fetomaternalhemorrhage?

Answer 45

Within 1 hour of delivery

Question 46

Rosette assay screen in ng test results.

Answer 46

< 1 rosette/ LPF = one dose of RhIg > 1 rosette/ LPF = quantitate bleed -> Kleihauer Betke Test

Question 47

Screening test of postpartum administration.

Answer 47

Rosette assay

Question 48

Confirmatory test for postpartum administration

Answer 48

Kleihauer Betke test

Question 49

Used to quantify the nummer of fetal red cells in maternal circulation

Answer 49

Kleihauer Betke Test

Question 50

Kleihauer Betke Test result

Answer 50

Hemoglobin F - remain pink ( resistant to acid) Maternal cells - ghost cells

Question 51

Blood smear morphology in RH HDN

Answer 51

Spherocytosis Macrocytes Hypochromia