Same Flashcards
Other names for Rh hemolytic disease of new born :
Rh isoimmunization
Rh incompatibility
Rh disease
Is the Disease always severe ?
No it ranges from mild to severe (mild to severe anemia and hydrops fetalis in very severe cases and then still birth)
Blood types of parents ?
When does it occur?
Rh+ father and Rh-ve mother
-During instances where mother (RBC -) and baby’s(RBC +) blood become mixed rogether
-IS of mother is activated and produces Ab against baby’s RBC Ag(ANTI D AB)
-Ab enter placenta in subsequent pregnancies and causes fetal hemolytic disease
What are the sensitizing events for development of anti-D ab?
Delivery
Miscarriage
Therapeutic abortion
Amniocentesis
Ectopic pregnancy
Abdominal trauma
External cephalic version
Rh blood titer levels:
1 to 8: titer monitor
More than 8: fetal monitroring because damage to ferus is possible
How to prevent hemolytic disease in NB?
Passive immunity: IM injection of anti RhD Ig (rhogram injection) during pregnancy or soon after delivery
When is the injection given
At 28 weeks in pregnancy (baby’s blood become to be mixed with mother’s blood at approximately the third trimester )
Within 72 hours of birth of a confirmed Rh positive baby
When is the Sensitivity to blood titers checked
-6 months after last injection following Rh+ baby
-it titers remain positive after 6 months —> sensitization has occured
The effect of the passive immunity will wear off after 2 weeks? T or F
False, the effect will wear off after about 4-6 weeks as the anti Rh Ab decline to 0 in maternal blood
all Rh- mothers who are pregnant should be given anti RhD Ig injection at 25w of gestation.
T or F
False. ALL RhD - pregnant mothers should be given Anti RhD Ig injection at 28 w
Is it necessary to give booster doe of Ig at 34 w
No
When do we give the baby a dose of Anti RhD Ig at birth
When baby is confirmed positive at birth
Why should we give the Ig at about 28w
Since sensitizing events mostly occur after 28 w of gestation
If mother is Rh-ve: Anti RhD Ig should be given AFTER any intervention as amniocentesis or CVS or after maternal bleeding also
T or f
True
What are the maternal blood tests used
Kleihauer betke test
Indirect coombs test
Kleihauer betke test Only confirm that fetal blood has passed to maternal circulation but CAN’T estimate the amount of fetak blood that has passed into mother
T or f
F
confirm that fetal blood has passed to maternal circulation AND estimate the amount of fetal blood that has passed into mother
Why do we do indirect coombs test
To identify IgG Ab directed against RBC Ag
And if it was positive: we can calculate titer to know the amount of immunization
And investigate whether this immunization is against which Ag( D ag or KEL blood group)
Fetal blood/ UC blood tests
Direct coombs
Full blood count
Bilirubin
What can Direct coombs test confirm
Detect Ab on surface of RBC
Confirm that fetus or neonates has an immune mediated hemolytic anemia
Total and indirect bilirubin are low
t or F
F- they are high indicating destruction of RBC
If indirect coombs test is positive- what is next step
Fetal Us
