Blood Bank Lecture and Canvas Questions

Which of the following antigens is part of an antithetical pair?

P1

D

M

Leb

M

Which phenotype is heterozygous?

M+N-S-s-

K-k+

Fy(a-b+)

Js(a+b+)

Js(a+b+)

A patient serum reacts with 2 or 3 antibody screening cells (a higher frequency antigen) at the AHG phase of testing. 8 of 10 crossmatched units were incompatible at AHG. All reactions were markedly enhanced with enzymes. Which antibody is likely reacting?

Anti-M

Anti-E

Anti-c

Anti-Fya

Anti-c

Which characteristics are true of all 3 of the following antibodies: anti-fya, anti-Jka, anti-K?

May show dosage, may cause severe hemolytic transfusion reactions

Detected at IAT phase and may cause hemolytic disease of the newborn and transfusion reactions

Not detected with enzyme treated cells, may cause delayed transfusion reactions

Requires IAT technique for detection, usually not responsible for HDN

Detected at IAT phase and may cause hemolytic disease of the newborn and transfusion reactions

An auto control gives a mixed field result, is this a valid test result?

Yes, the result shows that the patient has an autoantibody.

Yes, the patient has probably been recently transfused.

No, the panel cells cannot give mixed field results, something is wrong with the test system.

No, the control has failed, the test must be repeated until it gives valid results.

Yes, the patient has probably been recently transfused.

Sanjit, an 86 year old Indian male was collected for presurgical type and screen testing. The laboratory results were as follows:

Anti-A 4+

Anti-B 0

Anti-D 0

A1 cell 0

B cell 4+

Screen Cell 1

IS 0

37C 0

AHG 0

CC 2+

Screen Cell 2

IS 0

37C 0

AHG 0

CC 3+

Screen Cell 3

IS 0

37C 0

AHG 0

CC 2+

Why is there a discrepancy?

The cells for the antibody screen weren't completely washed

The anti-D was not added

The cells for the antibody screen weren't incubated appropriately

There is no discrepancy

There is no discrepancy

Takeo, a 17 year old Japanese man is brought into the ER with a stab wound. The physician orders transfusion of 2 units STAT. He has a history of anti-K in his plasma.

Utilizing donor population frequencies, how many units would you have to antigen type in order to find 2 compatible units?

1

2

4

8

2

Takeo, a 17 year old Japanese man is brought into the ER with a stab wound. The physician orders transfusion of 2 units STAT. He has a history of anti-K in his plasma.

How could an anti-K be developed?

at birth

Previous transfusion

medication

virally

Previous transfusion

Jayla, a 28 year old African American female is seen for routine prenatal work up for a second pregnancy. Her results indicate that she is A positive with an anti-Fya in her plasma. She is phenotyped as Fy-.

True or False, her child is at risk for HDN.

True

False

True

Jayla, a 28 year old African American female is seen for routine prenatal work up for a second pregnancy. Her results indicate that she is A positive with an anti-Fya in her plasma. She is phenotyped as Fy-.

What enhancement method might you use to aid in workup of her current antibody?

Enzymes

LISS

PEG

Fyb inhibition

Enzymes

Jayla, a 28 year old African American female is seen for routine prenatal work up for a second pregnancy. Her results indicate that she is A positive with an anti-Fya in her plasma. She is phenotyped as Fy-.

Based on her phenotype, what infection is she probably immune to?

Plasmodium falciparum

Pneumoccocol pneumoniae

Plasmodium vivax

Paroxysmal Nocturnal Hemoglobinuria

Plasmodium vivax

Jayla, a 28 year old African American female is seen for routine prenatal work up for a second pregnancy. Her results indicate that she is A positive with an anti-Fya in her plasma. She is phenotyped as Fy-.

Her phenotype is rare in her ethnic group.

yes

no

no

Which pair is NOT a set of antithetical antigens?

Jsa/Jkb

E/e

Fya/Fyb

M/N

Jsa/Jkb

A donor unit caused a delayed transfusion reaction where a patient developed an anti-Jsa. Given expected antigen frequencies, what is the likely population the donor is from?

Caucasian

Asian

Black

Hispanic

Black

Which set of antigens are inherited on the same chromosome?

MNS and P/Glob

Kell and Kidd

Duffy and Rh

Lutheran and ABO

Duffy and Rh

From the list, select all antigens that are susceptible to enzyme treatment.

Rh

Kell

Kidd

Duffy

Lewis

MNS

P/Glob

Lutheran

Duffy and MNS

If my patient has an unexpected antibody causing a reverse type discrepancy, which antibody am I LEAST likely to suspect?

I

M

P

s

s

Usually, reverse discrepancies are caused by cold reacting IgM antibodies, so you want to find the the antibody that is IgG. M, I, and P are cold reacting IgM, and s is warm reacting IgM, therefore the most likely answer is s

Due to it being the second most immunogenic blood group system (besides Rh) which blood group am I giving phenotypically matched cells to sickle cell patients?

Duffy

Kidd

Kell

Lutheran

Kell

Match the blood group system with the disease associated with it.

Duffy

Kidd

Rh

P/Glob

Delayed Hemolytic Transfusion Reaction

Paroxysmal Cold Hemoglobinuria

Malaria Vivax

Hydrops Fetalis

Duffy: Malaria Vivax

Kidd: Delayed Hemolytic Transfusion Reaction

Rh: Hydrops Fetalis

P/Glob: Paroxysmal Cold Hemoglobinuria

A patient has an antibody reactive with 8 out of 10 cells at room temperature. It is enzyme resistant and neutralized by cyst fluid. Which antibody do you suspect?

anti-N

anti-P1

anti-P1PPk

anti-IH

anti-P1

How many panel cells containing E antigen need to demonstrate a positive agglutination reaction with the unknown antibody in order to statistically rule-in anti-E?

1

2

3

4

3

What would you call the procedure where you mix patient plasma and patient cells, then read/grade reactions at IAT phase?

Phenotype

DAT

Auto Control

Antibody ID

Auto Control

(Multiple options available) Choose which circumstance does NOT require phenotype testing.

An Rh-negative patient with a newly identified anti-D

Recently transfused patient with a known anti-Fya

Units for a patient with known anti-K

Units for a patient with a low incident antibody

1. An Rh-negative patient with a newly identified anti-D

2. Recently transfused patient with a known anti-Fya

3. Units for a patient with a low incident antibody

(Choose all that apply) An antibody is clinically significant when:

Correct answer:

It may cause transfusion reaction

It does not cause HDN

It is high incident

It is identified as an HTLA

It may cause transfusion reaction

For rule ins, if a single antibody isn't positive for all of my positive reactions, what is likely?

It is an autoantibody

The patient has multiple antibodies

The patient has a negative antibody screen

It is ruled out

The patient has multiple antibodies

Which of the following is NOT part of follow-up testing required to "complete the workup" of an antibody ID?

Phenotype the patient cells for all antibodies identified

Phenotype potentially transfused red cell products for all antibodies identified

If the auto control is positive, perform a DAT

Select a cell positive for the antigen to be sure that the antibody was accurately identified

Select a cell positive for the antigen to be sure that the antibody was accurately identified

How many points does a homozygous rule out count for?

2

If you have a positive antibody screen, what test should you perform next?

Antibody ID

Phenotype

Blood Type

Auto Control

DAT

Antibody ID