Test 7 Flashcards
What group of antibodies is the most frequent cause of HDN
ABO
Which antibody is the most common cause of HDN
Anti-A,B
Is ABO HDN usually severe
No
What group of antibodies is the most frequent cause of severe HDN
Rh antibody
Is cord blood mom or baby blood
Baby
What hematological changes are seen with HDN
Increased retic and NRBC
What chemistry changes are seen in HDN
Increased indirect bilirubin
In HDN why does baby’s bilirubin rise even more after birth
Mothers liver not there to compensate and baby’s lover takes 3 days to reach total function
Which bilirubin is more dangerous for the baby
Indirect
Unconjugated bilirubin had affinity for what tissue
CNS
What is kernicterus
Bilirubin precipitates in baby brain cells
Which children are at greatest risk for kernicterus
Acidotic, hypoxic, premature birth, low serum albumin
Objectives of exchange transfusion
Decrease bilirubin
Remove baby Ab coated RBCs
Provide RBCs w/ O2 carrying capacity
Decrease level of incompatible Ab in baby
What will simple transfusion help with
Providing O2 carrying capable RBCs
Samples that can be used for cross match on baby
Mothers serum
Eluate from baby cells
Baby’s serum
How long is it acceptable to use mothers sample for crossmatch
4 months
Serological test commonly used to predict severity of HDN
Antibody titer
When doing titers what is done to avoid discrepancy
Run previous specimen alongside current
How does monitoring OD of amniotic fluid help predict worsening of disease
OD usually declines after 2nd trimester
HDN causes it to stay the same or increase
What does cord blood testing usually include
ABO, Rh and DAT
Cord blood testing is usually ordered on infants of what mothers
O or Rh negative mom
Test of choice to screen for FMH in Rh negative no there’s with Rh positive babies
Rosette test
If rosette test is negative what will be done
Give 1 vial RhIg
If rosette test is positive what will be done
Quantitative test such as flow cytometry or K-Betke
What type of test is K-Betke
Staining technique used to detect fetal Hgb
Test of choice to screen of FMH of Rh positive moms
Quantitative test
Test of choice to screen for FMH in Rh negative moms with weak D positive babies
Quantitative test
How to calculate vials of RhIg
Number fetal cells/ number adult cells100= % fetal cells
%fetal cells50= FMH
FMH/30= vials
Vials+1
Anemia that results when an individual forms an antibody against RBC antigens
Autoimmune hemolytic anemia
Term for anemia that results when an individual forms an antibody against drug
Drug induced autoimmune hemolytic anemia
Autoimmune hemolytic anemia classified into what categories
Warm autoimmune hemolytic anemia
Cold hemagglutinin disease
Which AIHA is more common
WAIHA
What temp do antibodies seen in WAIHA react best
37C
Extra vascular hemolysis occurs where
Liver and spleen
Cells carrying low levels of IgG are cleared in what organ
Spleen
Cells sensitized by complement or higher levels of IgG cleared by what organ
Liver
Lab findings associated with intravascular hemolysis
Hemoglobin in plasma and urine
Increased bilirubin
Decreased haptoglobin
Lab findings associated with extra vascular hemolysis
Increased bilirubin
Urobilinogen
Test to determine if circulating antibody and the antigens on RBCs have bound
DAT
When a DAT is positive what will RBCs most likely be coated with
Both IgG and complement
If only one protein is coating RBC surface in DAT what is it likely
IgG
To remove protein coating patient RBCs what procedure will be done
Elution
Why shouldn’t patients with WAIHA be transfused
AutoAb makes finding compatible blood and identifying alloAB difficult
Auto AB shortens life of transfused cells
Does presence of ab in serum indicate mild or severe disease
Severe
Procedure used to remove autoantibody from patients cells so they can be type
Chloroquine diphosphate for IgG
Think reagent for IgM
Procedure used to remove AutoAb from patients serum
Adsorption
Procedure used to remove AutoAb from patients serum
Adsorption
What determines if autologous or homologous cells are used for adsorption
If patient has been recently transfused
Type of treatment will WAIHA usually receive
Glucocorticoid steroid
Splenectomy
Cytotoxic drugs
Age group and disease state usually seen with chronic CHD
Over 50
Lymphoproliferative disorders
Age group and disease state usually seen in transient CHD
Adolescents
Infections
Cold reactive AutoAb that react at what temp are clinically significant and why
28-31C can cause ongoing hemolysis at room temp
In CHD what protein should be seen coating cells when DAT is performed
Complement
Titer of cold reactive antibody usually associated with what
Thermal amplitude
Infections associated with CHD
Mycoplasma pneumoniae
Infectious mono
Auto anti-P in PNH is called what
Doneth-Landsteiner
Treatment for CHD
Keep warm
Folic acid
What temp is EDTA tube for cold agglutinin test kept at and why
37C
So antibody comes off of RBCs to perform testing
What cells are used to perform cold agglutinin test
Patient cells with screening cells,
Best tracing cell is used in overnight test
Significant titer rise
> 128
True drug induced hemolytic anemias caused by what
Methyldopa/aldomet
In true drug induced hemolytic anemia what type of cells will eluate react with
All RBCs
What type of drug is usually involved in anemia resulting from drug adsorption
IV penicillin
What are the only type of cells eluate from patient with drug adsorption mechanisms
Penicillin coated RBCs
What differentiates drug adsorption mechanism from drug dependent mechanism
Drug dependent may bind drug at any site in body
Drug adsorption only destroys cells with drug on surface
Another term for drug dependent mechanism
Immune complex mechanism
Innocent bystander mechanism
What cells will eluate of patient with drug dependent mechanism react
None
What differentiates membrane modification mechanism from drug adsorption and drug dependent mechanism
It does not cause RBC destruction
In membrane modification mechanism what will DAT demonstrate
IgG
Complement
Or both
In membrane modification mechanism with what cells will eluate react
None
What is HDN
Immune destruction of fetal or newborn RBCs due to sensitization by maternal IgG