KIDD,Duffy,MNS

Question 1

What Kidd phenotype is twice as common in blacks than white?

Answer 1

Jk(a+b-)

Question 2

The Jk(a-b-) phenotype is very rare, what population is it primarily encounted in? (2)

Answer 2

• Finns

- Polynesians

Question 3

What is the function of the Kidd protein?

Answer 3

Urea transport protein

Question 4

Jk (a-b-) cells are resistant to what?

-Individuals with this phenotype have what kind of defect?

Answer 4

Hemolysis in 2M urea

-Mild urine concentrating defect

Question 5

Kidd phenotype prevalence in Blacks (decreasing order).

Answer 5

• Jk(a+b-) - 60%
• Jk(a+b+) - 30%
• Jk(a-b+) - 10%
• Jk(a-b-) - rare

Question 6

Kidd phenotype prevalence in Whites (decreasing order).

Answer 6

• Jk(a+b+) - 50%
• Jk(a+b-) - 30%
• Jk(a-b+) - 20%
• Jk(a-b-) - rare

Question 7

What type of an antibodies are Kidd antibodies?

• Temp
• Class
• Acquisition

Answer 7

• Warm reacting
• IgG antibodies
• Acquired only through exposure

Question 8

What are Kidd antibodies notoriously known for?

Answer 8

Difficult to detect

“tricky Kidd”

Question 9

Why are Kidd antibodies difficult to detect?

Answer 9

• Display dosage and may only react with homozygous cells (may result in false-negative crossmatch)
• Tend to fall below the threshold for detection over time

*Historical Kidd Abs is reason enough to give Kidd antigen negative blood (CHECK BLOOD BANK RECORDS!)

Question 10

Kidd antibodies most often only react at what phase?

Answer 10

AHG

Question 11

Kidd antigens are _____ by enzymes.

Answer 11

Enhanced

Question 12

What is the most common cause of delayed hemolytic transfusion reactions?

Answer 12

Kidd

Question 13

Does Kidd cause hemolytic disease of newborn?

-Why?

Answer 13

Rarely

-Weakly expressed by fetus

Question 14

What 2 antigens comprise the Duffy system?

Answer 14

Fya and Fyb

Question 15

Duffy antigens are present on Duffy associated receptor for chemokines (DARC), which is a receptor for what?

Answer 15

Plasmodium vivax (malaria)

Question 16

Which phenotype is more common:

-F(a-b+) or F(a+b-)

Answer 16

F(a+b-)

Question 17

What is the Duffy phenotype that differs most between blacks and whites?
-Whats the explanantion?

Answer 17

Blacks - Fy(a-b-) is common (68%); Whites - Rare

-confers resistence to Plasmodium vivax

Question 18

Because of differeing mechanisms of Duffy negativity in whites and blacks, what is true about the development of Fy antibodies?

Answer 18

Most Fy(a-b-) Blacks do NOT form anti-Fy Ab
-Fy(a-b-) Whites do for an anti-Fy Ab

Question 19

What type of an antibodies are Duffy antibodies?

• Temp
• Class
• Acquisition

Answer 19

• Warm
• IgG
• Acquired through exposure

Question 20

Duffy Antibodies (do or do not) show dosage effect.

Answer 20

Duffy antibodies show dosage

Question 21

Duffy antigens are _______ by enzymes.

Answer 21

Destroyed

Question 22

T/F: Duffy antibodies are capable of causing HTR and HDFN.

Answer 22

True

Question 23

MNS antigens - Which genes display genetic linkage?

Answer 23

MN and SsU genes

Question 24

MNS antigens - Most frequent haplotypes?

Answer 24

Ns and Ms

Question 25

MNS antigens - M and N antigens are found on what?

Answer 25

Glycophorin A

Question 26

What is are the phenotype prevalence of MNS antigens?

Answer 26

- M+N+ (50%) - M+N- (25%) - M-N+ (25%)

Question 27

Where do the S, s, and U antigens reside?

Answer 27

Glycophorin B

Question 28

S, s, and U frequencies?

Answer 28

-s and U - high prevalence (98%) S antigen -Whites (50%) -Blacks (30%)

Question 29

Anti-M antibodies: - Temp - Class - Clinical Sig or Not - Acquisition

Answer 29

MNS antibodies: - Cold - IgM - NOT clinically significant - Naturally occuring

Question 30

Why are anti-N antibodies rare?

Answer 30

epitope on Glycophorin B has N like antigenicity

Question 31

When are Anti-Nf antibodies formed?

Answer 31

Dialysis patients exposed to formaldehyde | -Induced formation of Nf antigen on RBCs

Question 32

Anti-S, s, U Antibodies: - Temp - Class - Clinical sig? - Acquisition

Answer 32

Anti-S, s, U Antibodies: - Warm - IgG - Clinically Significant - acquired following exposure

Question 33

Do MNS antibodies display dosage?

Answer 33

Yes

Question 34

M and N antigenicity is _______ by enzymes.

Answer 34

Destroyed