MLT 125 Final Exam Flashcards by Alex Olsen

Main Ig in primary response

IgM

How well did you know this?

Not at all

Perfectly

Main Ig in secondary response
incomplete or blocking antibodies
predominant Ig type found in the Rh system

IgG

How well did you know this?

Not at all

Perfectly

Explain Landsteiner’s Law

Ab are present in plasma only when the corresponding Ag is NOT present on the RBC.

How well did you know this?

Not at all

Perfectly

Where are antigens found? Antibodies?

on the rbc

in the plasma/serum

How well did you know this?

Not at all

Perfectly

Antibodies that are found in the following blood groups:
A
B
O
AB

A - anti B
B - anti A
O - anti A, anti B, anti A,B
AB - none

How well did you know this?

Not at all

Perfectly

exposure to genetically different AG from same species: transfusion, pregnancy

alloantibody

How well did you know this?

Not at all

Perfectly

produced to self Ag; autoimmune diseases; is removed by elution

autoantibody

How well did you know this?

Not at all

Perfectly

The amount of H substance demonstrated on the cells in order of decreasing reactivity

O
A2
B
A2B
A1
A1B

How well did you know this?

Not at all

Perfectly

Testing for presence or absence of RBC Ag with antisera; looking for what Ag is on pt blood

Forward grouping

How well did you know this?

Not at all

Perfectly

Testing for presence or absence of Ab in pt serum with screening cells

Reverse grouping

How well did you know this?

Not at all

Perfectly

What is the purpose of performing an absorption?

remove Ab from serum or plasma

How well did you know this?

Not at all

Perfectly

List five examples of factors influencing Ag-Ab reactions

Time
Centrifugation
pH
Ag-Ab ratio
Temp
Ig type
Ionic strength medium
Incubation time
Binding sites

How well did you know this?

Not at all

Perfectly

Why don’t labs perform reverse blood groupings on newborns?

RBC Ag isn’t fully developed

How well did you know this?

Not at all

Perfectly

Name the antisera used in ABO/Rh

anti-A, anti-B, anti-D

How well did you know this?

Not at all

Perfectly

Anti-A1 is occasionally found in individuals of what blood group?

How well did you know this?

Not at all

Perfectly

What is one of the best ways to test a pt to see if they have a subgroup or variant of the A blood type?

test plasma/serum with A1 cells

How well did you know this?

Not at all

Perfectly

Describe two types of AHG and what is in them

polyspecific; anti-complement and anti-IgG

monospecific; one or the other

How well did you know this?

Not at all

Perfectly

The lectin in what plant has a specificity for anti-H?

ulex europaeus

How well did you know this?

Not at all

Perfectly

What is the main purpose of washing rbc’s used for testing in an antiglobulin test?

to prevent neutralization of AHG by globulins

How well did you know this?

Not at all

Perfectly

The extract from what plant is used to distinguish type A1 cells from other other A cells?

Dolichos biflorus

anti_a1 lectin

How well did you know this?

Not at all

Perfectly

The weakest agglutination would be seen with anti-A in what A subgroup?

How well did you know this?

Not at all

Perfectly

detects Ab and or complement attached to RBC
useful in detecting HDN, HTR, AIHA
gamma and beta globulins

DAT

How well did you know this?

Not at all

Perfectly

detects Ab or complement attached to RBC, in tube testing
incomplete Ab to potential donor rbc
rbc phenotyping
titre
Ab screen and compatibility testing

IAT

How well did you know this?

Not at all

Perfectly

How can cold agglutinins be excluded in a crossmatch?

prewarm Xm

cold AC

How well did you know this?

Not at all

Perfectly

What is the purpose of anti-A1 lectin?

to ID A1 subgroup

What is the purpose of anti-A,B antisera?

to detect subgroups of A that are weaker than A2

What type of test would demonstrate that group A or B fetal cells have been coated with the maternal group O antibodies?

DAT

What type of antibodies does an antiglobulin test detect?

IgG | blocking/incomplete

Which rare blood type produces natural anti-H antibodies?

Oh; Bombay

Name a procedure you could perform in BB to remove rouleaux formation.

saline replacement

ABO and Rh antibodies are most often implicated in what serious condition that affects newborns and fetuses?

HDFN | mother produces IgG alloAb

What must be done to a donor unit to firmly establish that it is indeed Rh =?

weak D test

When is Rh immunoglobulin (Rhogam) give to Rh = mothers?

28 weeks and within 72 hours of delivery

What causes kernicterus in newborns?

infiltration of the brain and spinal cord with unconjugated bilirubin which causes permanent damage to CNS

What type of BB testing is used to detect weak D?

IAT - in vitro

Before testing, what must be done to all cord cells and why?

Wash to remove Wharton's jelly | interfers with blood typing

What causes HDFN?

Antibodies directed against the Rh Ag D destruction on rbc of fetus and neonate by antibodies produced by the mother(Rh=). maternal cells lack Ag that fetal cells have

``` What substances do the following individuals secrete into their saliva in terms of ABO? A blood group B blood group O blood group AB blood group ```

A, H B, H H none

How must an individual inherit Lewis, secretor, and H genes in order to secrete Le^b substance?

Le, Se, H | Le, Se, h

You have a patient that has developed Lewis antibodies. What type of donor blood would you want to give them?

Le(a-b-)

Genotypes le, se, and h are said to be what?

recessive | amorphic

What percentage of Caucasians are secretors?

80%

What components are used for testing in a major XM and what is the purpose of this testing?

donor cells to recipient plasma | to ensure safety of transfusion and pt survival

Which antibodies can show up as cold agglutinins?

M, N, I, P1, Le^a, Le^b

Which antibodies belong to the Kidd blood group system?

Jk^a | Jk^b

What antigen is known to be sex linked?

Xg^a

The i antigen is most prevalent in what type of population?

newborns

Which antibodies are know to cause delayed HTR?

Kidd

Why is transfusion of specific blood components preferable to the use of whole blood?

``` treat many pts with a single donation reduces risk of circulatory overload not wasted reduces reactions "safer" concentrated form of the required fraction can be administered ```

Name some of the routine testing generally performed on donor blood.

``` ABO/Rh Ab screen Syphilis Viral resting; HIV, Hep, CMV weak D ```

self donation | advantage for rare blood types

autologus donation

intended for specific recipient

directed donation

What is emergency release?

an order for blood accompanied by the signed statement of the doctor accepting full responsibility for the transfusion of uncrossmatched, O= blood.

concentrated; small amount of plasma

platelets

5 days | 20-24 degrees/RT with agitation

platelets

concentrated cells; small amount of blood

RBC

CPDA - 35 days | 1-6 degrees

packed rbc

10 yrs | -65 to -120 degrees

frozen rbc

FFP

fresh frozen plasma

1 yr | -18 degrees

FFP | Cryo

insoluble portion of plasma that remains after thawing FFP

cryo

What is therapeutic phlebotomy? Why is it used? Name two conditions that might require this kind of treatment.

Blood letting | removal of blood from pt with certain conditions; such as polycythemia, hemochromatosis, porphyrias

How long should someone wait between whole blood donations?

8 weeks

How often should a new sample be collected on a blood recipient when a series of transfusions are to be administered over a period of time?

3 days

When transfusing packed rbc what is the total amount (+ or - 10%) that is routinely transfused?

280 mL

Why is there storage limits of 21 days put on CPD blood stored at 5 degrees?

to preserve viability of 70% of red cells post transfusion

List reasons for a permanent deferral from donating blood

``` IV drug user hemophiliac MS viral hepatitis clotting disorders ```

What is plasmapheresis?

removal of blood; separation of plasma from blood; rbc returned to donor

What is the most common of all transfusion reactions? | What causes febrile reactions to occur?

Febrile and allergic | leukocyte Ab, sytokines/pyrogen, plt Ab

Name 2 acceptable methods for thawing FFP

FDA approved microwaves | water bath

Which government agency is regulatory agency providing licensure for BB reagents?

FDA

Packed red cells if hepatic seal is broken but unit has been refridgerated

24 hours

Six units of plt have been pooled in an open system

4 hour at 20-24 degrees

FFP has been thawed is refridgerated

24 hours

What is the temp limit for shipping packed rbc?

1-10 degrees

What does refractory mean and which blood component is it associated with?

unresponsive; to plt transfusion

Why are patient specimens kept in the lab after testing is completed and for how long?

in case of concern; transfusion reactions, mis-ID | 7 days

Name the methods of good record keeping in the BB

indelible ink record data in correct log cross out, date and initial mistakes

How long are most BB records kept in the lab?

12 months

What is the number one source of error in BB

clerical; mislabeling

Factor VIII deficiency

Cryo

Marked thrombocytopenia

plt

Factor V deficiency

FFP

Exchange transfusion

fresh whole blood

Severe burns

human serum albumin

Chronic anemia

packed red cell

Acute blood loss

whole blood

Hemophilia

Cryo