Lab 2: 2/2 ABO Typing Flashcards

1
Q

is defined as using reagent red cells with known ABO antigens and testing the serum of the patient for ABO group antibodies.

A

Reverse grouping (serum typing)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

The only Rh system antigen routinely tested for is the____ antigen.

A

D

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Generally, clotted or anticoagulated blood samples may be used for ABO testing, with a preferred sample being ______.

A

EDTA

The red cells may be suspended in autologous serum, plasma, or saline, or they may be washed and resuspended in saline.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

If specimen cannot be tested right away, what temp should it be stored at?

A

2-8oC

-Alternatively, serum or plasma can be separated from red blood cells and stored frozen.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What type of specimens should not be used?

A

Blood specimens exhibiting gross hemolysis or contamination

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Why should samples not be drawn in tubes with neutral gel separators?

A

can cause false-positive

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Can hemolyzed samples be used?

A

no

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Clotted specimens or those collected in EDTA should be tested within ___ days of collection.

A

7

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

The antisera reagents should be stored at _______C. And should not be used if turbid.

A

2oC – 8oC

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What does the cells reagent contain?

A

-2-4% suspension of pooled C-D-E red blood cells suspended in a buffered solution to retard hemolysis and/or loss of antigencity
-EDTA is added to inhibit complement activation and prevent hemolysis when RBCs are tested with fresh serum.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What temp should the cells reagent be stored at?

A

1-10oC when not in use.

Do not freeze or expose to elevated temperatures.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What should be done to the vial before using the cells reagent?

A

suspend by gently inverting each vial several times.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

How long should all tubes be centrifuged for?

A

10 seconds

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

refers to mixed reactions during cell typing where two distinct cell populations are present

A

Mixed-field agglutination

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

How often should quality control of reagents be perfomed?

A

each day

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Quality control:

Anti-A
Anti-B
Anti-A,B

should be tested with….

A

A1, A2, B and O cells

17
Q

Tests should be read immediately by the “__________” procedure. Excessive agitation may disrupt weak agglutination and produce false negative results.

A

tip and roll

18
Q

excessive g force during centrifugation will lead to…

A

difficulty in resuspending the cell button

19
Q

Inadequate centrifugation may result in….

A

agglutinates that are easily dispersed

20
Q

Causes of false-positive or false-negative results?

A

-contamination of test materials
-improper reaction temperature
-improper storage of materials
-omission of test reagents -certain disease states

21
Q

Why should tests involving cord/neonatal red cells be interpreted with particular care?

A

ABO antigens are not fully expressed at birth

22
Q

Decreased antibody activity to A and B antigens has been reported with samples from…

A

debilitated or elderly patients or patients who are less than 6 months old.

23
Q

Why are better results obtained with fresh samples?

A

The expression of certain red cell antigens may diminish in strength during storage, particularly in EDTA and clotted samples.

24
Q

What may interfere with serum grouping tests?

A

Non-ABO-related agglutination