Blood Bank Week 2

Which systems are most often associated with IgM antibodies?

Lewis
I
P
MN

Which systems are most often associated with IgG antibodies?

Rh
Duffy
Kell
Kidd

Which immunoglobulin class of antibodies would cause agglutination at room temperature that disperses at 37°C?

IgM

To produce Le-b antigens on the red cells which gene must be inherited?

Le
Se
H

What Lewis phenotype do all newborns have?

Lea- Leb-

Which antibodies are enhanced by lowering the pH to 6.5?

MNS

Which part of the Black population can form anti-U antibody?

1%

Which persons can produce an P1 antibody?

P2 individuals

Which blood group system is associated with PCH? (paroxysmal cold hemoglobinuria)

autoanti-P (Donath-Landsteiner antibody)

Which antibody is associated with increased incidence of spontaneous abortion?

anti-PP1PK

List the substances that will neutralize anti-P1 antibodies

hydatid cyst fluid

Which three blood group systems exhibit linkage?

MNSU
?
?

Which infections are associated with the presence of these antibodies in the patient's serum: Anti-I

Mycoplasma Pnuemoniae
Cold Hemagglutin Disease

Which infections are associated with the presence of these antibodies in the patient's serum: Anti-i

Infectious mononucleosis
Lymphoproliferative Disease
Cold Hemagglutin Disease (occasionally)

What I/i phenotype do all babies have at birth?

i

Which blood group antibody is seen most often other than Rh antibodies?

Kell

Which blood group antigens are destroyed by sulfhydryl compounds?

Kell

Which Kell antigens are seen in high frequency in Blacks?

K-k+
Kp(a-b+)
Js(a-b+)

Which Kell antigens are seen in the white population?

K-k+
Kp(a-b+)
Js(a-b+)

Which disease is associated with McLeod phenotype?

McLeod Syndrome
Chronic Granulomatous Disease

Protection against malaria is associated with which genotype usually seen in Blacks?

Fy(a-b-)

Which two blood group systems are associated with delayed HTR?

Kidd
Duffy

Which blood group antibodies exhibit dosage?

Duffy
Kidd
MNSU

Which blood group antigens are destroyed by enzyme enhancement?

Duffy
MN

Which blood group antigens are enhanced by enzyme enhancement?

Kidd
P
I
Lewis

What is the function of rabbit red cells stroma in testing procedures?

To remove cold autoantibodies from patient samples and allow alloantibody detection

Which blood group is seen primary in native South Americans and Asians?

Diego

What is the purpose of the prewarming technique?

to get rid of cold agglutination

If any antibody is identified in recipient serum, what must be done before they are given red blood cells?

Check to ensure the red cells don't have target antigen

What are low frequency antigens?

Antigens that present in less than 1% of the population

What are high frequency antigens?

Antigens that present in more than 99% of the population

What are the low frequency antigens?

Cw
V
Kpa
Jsa
Lua
Mg
Vw
Dia
Wra
Cob

What are the high frequency antigens?

Kpb
k
Jsb
Lub
I
Ge
Tja
Vel
Yta
Dib
Coa
U

Which are the most common HTLA antibodies?

Chido (Ch)
Holley (Hy)
McCoy (McCa)
Rodgers (Rg)
Knops (Kna)
York (Yka)
John Milton Hagen (JMH)
Cost (Cs^a)

Describe the purpose of HLA testing in platelet transfusion?

Antibodies to platelets may cause neonatal alloimmune thrombocytopenia (NAIT): destruction of newborn platelets by maternal antibody; Post-transfusion purpura (PTP): destruction of platelets after transfusion

Which HLA antigen is found on red blood cells?

none

What is the blood group of red cells used in antibody screening and identification? Why?

Group O because they lack A and B antigen and therefore won't react ABO antibodies

List five reasons for preforming the IAT

-antibody screen
-antibody panel
-crossmatching
-weak D testing
-phenotyping

If the antibody screen is positive, what test is done to identify the antibody?

Antibody identification panel

If the autocontrol (AC) is positive, which test is done next?

DAT

What results on a panel of cells indicate the presence of a single antibody in the patient's serum?

Same agglutination strength reaction and perfect pattern match

What results on a panel of cells indicate the presence of two or more antibodies?

Variation in agglutination strength in single phase

Which class of immunoglobulin require enhancement for detection?

IgG

Which conditions or diseases cause a positive DAT?

Warm and cold autoimmune hemolytic anemia, HDFN, a drug-related mechanism, or an antibody reaction to transfused red cells

What procedure should be performed if the DAT is positive?

Elution

Describe the following grades in the agglutination in the gel testing: 0

Negative; no agglutination or hemolysis

Describe the following grades in the agglutination in the gel testing: 1+

Small agglutinates, free red cells in background

Describe the following grades in the agglutination in the gel testing: 2+

Medium agglutinates, clear background

Describe the following grades in the agglutination in the gel testing: 3+

Several large agglutinates, clear background

Describe the following grades in the agglutination in the gel testing: 4+

One solid agglutinate

List the antigens that are destroyed by proteolytic enzyme enhancement

Fya, Fyb, M, N, S, s

List the antigens that are enhanced by enzyme pretreatment

Kidd, Rh, Lewis, I

Which antibodies can be removed from sensitized red cells by dithiothreitol and 2-mercaptoethenol?

IgM
(also destroys Kell ANTIGENS)

Which immunoglobulin class can be removed from sensitized red cells by ZZAP reagent?

IgG
warm autoantibodies

What is the incubation time when using LISS enhancement?

LISS: 10-15 mins.

How is donor blood selected after antibody identification?

Phenotyping
Compatibility testing

Why are IgM antibodies not considered clinically significant?

They do not react in vivo

Why are IgG antibodies considered clinically significant?

They do react in vivo

List the substances that reduce the zeta potential to enhance agglutination?

LISS, BSA (albumin), PEG, Immuadd

Which antibody specificities are commonly seen for warm AIHA?

Rh antibodies, especially autoanti-e

Which antibody specificities are commonly seen for cold AIHA?

autoanti-I, autoanti-H, autoanti-IH

Which antibody specificities are commonly seen for PCH?

autoanti-P (Donath-Landsteiner antibody)

If a patient has a positive DAT and the panel on the eluate is negative, what is the most probable cause of the DAT results?

Warm autoantibodies to medications

If the antibody screen and auto control tubes agglutinate at the immediate spin phase and the agglutination disappears after 37°C incubation, what conclusion can be drawn and what should you do?

Cold reacting antibody; prewarm technique or REST adsorption

Which two procedures are useful in detecting anti-I?

Cold panel, cord blood cells

Which antibodies are best detected by enzyme enhancement?

Enhanced: Kidd, Rh, Lewis, I
Destroyed: Fya, Fyb, M, N, S, s

If you suspect a patient's serum has anti-Fya and another warm reacting antibody, how can the Duffy antibody be removed so that the other antibody can be identified?

Enzyme treatment to destroy Fya

Which antibodies are extremely labile and causes delayed HTR?

Kidd, Duffy

If all of the following cells of a panel are agglutinated except the AC, what is the patients antibody most probably directed against?

High incidence Ag-Antibody; Multiple antibodies; HTLA antibodies

Anti-D optimum temperature

37 degrees C

Anti-k optimum temperature

37 degrees C

Anti-Fya optimum temperature

37 degrees C

Anti-Jka optimum temperature

37 degrees C

Anti-M optimum temperature

RT

Anti-s optimum temperature

37 degrees C

Anti-Leb optimum temperature

RT

Anti-Xga optimum temperature

37 degrees C

Anti-Lub optimum temperature

RT

Describe the adsorption procedure and indicate its purpose.

Adding RBCs with known antigens to bind known antibodies in patient sample. This removes the antibodies you already know about so you can detect any remaining unknown antibodies

If a patient has cold AIHA and exhibits a positive DAT, what specifically causes in vivo red cells sensitization?

complement binding

Define elution

removal of antibody from DAT positive RBCs in a solution called an eluate which is tested for antibody specificity

Rule of three

For every Ab that is IDed you want 3 positives that are separated from other reactions (positive for one and negative for the others)

Which antibodies is commonly associated with delayed transfusion reactions?

Duffy
Kidd

Which phenotype is associated with resistance to Plasmodium vivax?

Fy(a-b-)

Which antibodies are enhanced by enzymes?

Kidd
Lewis
P
I

Which antibodies are destroyed by enzymes?

Duffy
MN

Which antibodies are typically IGM?

Lewis
P
MN
I

Which antibodies are typically IgG

Rh
Kidd
Kell
Duffy

Which blood group system's antigens are associated with glycophorin A and glycophorin B?

MNS

Which red cell phenotype is associated with the McLeod phenotype?

absence of Kx antigens

What is the common specificity of cold autoantibodies?

I

Which of the following antibodies requires the antiglobulin test for in vitro detection?

anti-U

What procedure helps distinguish between an anti-Fya and anti-Jka in an antibody mixture?

testing ficin-treated panel cells

What phase does anti-K agglutinate in?

IAT

What is the disease commonly associated with McLeod phenotype?

chronic granulomatous disease

What is the most likely Lewis phenotype of a nonsecretor?

Le(a+b+)

Which antigens are present on red blood cells with the P1 phenotype?

P1, P, Pk

Which antibodies are enhanced by lowering the pH to 6.5?

MNS

Which blood group system is associated with PCH (paroxysmal cold hemoglobinuria)?

autoanti-P (Donath-Landsteiner antibody)

Which antibody is associated with increased incidence of spontaneous abortion?

anti-PP1PK