BMS 185 LAB Midterm Flashcards
1
Q
What must you do to the tube before you read the agglutination rxn?
A
With the button facing you, gently shake out the tube to dislodge the button
2
Q
What is a 0 agglutination rxn?
A
no agglutination
3
Q
What is a 1+ agglutination rxn?
A
small clumps and cloudy background
4
Q
What is a 2+ agglutination rxn?
A
medium clumps and clear background
5
Q
What is a 3+ agglutination rxn?
A
large clumps with clear background
6
Q
What is a 4+ agglutination rxn?
A
solid button and clear background
7
Q
What is a W+/weak agglutination rxn?
A
if you see agglutination under the microscope
8
Q
What blood type would have A antigen present on RBCs?
A
A
9
Q
What blood type would have Anti-B naturally occurring in plasma?
A
A
10
Q
What blood type can receive A or O RBCs?
A
A
11
Q
What blood type can receive A or AB plasma?
A
A
12
Q
What blood type would have B antigen on RBCs?
A
B
13
Q
What blood type would have Anti-A naturally occurring in plasma?
A
B
14
Q
What blood type can receive B or O RBCs?
A
B
15
Q
What blood type can receive B or AB plasma?
A
B
16
Q
What blood type would have A and B antigens present on RBCs?
A
AB
17
Q
What blood type would have anti-A and anti-B are not found in the plasma?
A
AB
18
Q
What blood type can receive A, B, AB or O RBCs?
A
AB
19
Q
What blood type can receive only AB plasma?
A
AB
20
Q
What blood type does not have A or B antigens on RBCs?
A
O
21
Q
What blood type would have both Anti-A and anti-B naturally occurring in plasma?
A
O
22
Q
What blood type can only receive O RBCs?
A
O
23
Q
What blood type can receive A, B, AB, or O plasma? (aka universal plasma receiver)
A
O
24
Q
What does it mean when D antigen is present on RBCs (Reagent Anti-D is positive)?
A
Rh positive
25
What does it mean when D antigen is NOT present on RBCs (Reagent Anti-D is negative)?
Rh negative
26
Is anti-D naturally occurring (born with D antigens)?
No
27
Does a Rh negative person become sensitized once they are exposed to Rh positive RBCs (via transfusion and/or pregnancy)?
Yes
28
What color EDTA tube is used for ABORH testing?
purple or pink
29
Can you use hemolyzed specimens for ABORH testing?
No (it MUST be rejected if hemolyzed [considered positive rxn])
30
Can you use Icteric specimens for ABORH testing?
Yes
31
What are Icteric specimens?
plasma with extra bilirubin
32
What color is icteric specimens?
dark yellow or amber
33
Can you use Lipemic specimens for ABORH testing?
Yes
34
What are Lipemic specimens?
plasma with extra lipids/fats
35
What do lipemic specimens look like?
cloudy
36
What is needed for front type and Rh testing?
1 drop 3-5% suspension of patient’s RBCs + 1 drop antisera reagent
37
What does front type testing test for?
antigens on the patient's RBCs
38
What does antisera reagent mean?
reagent that imitates serum with a particular ANTIBODY
39
What is used with antisera reagents?
patient's RBCs
40
Anti-A antisera reagent reacts with
any A antigens present on the patient’s RBCs
41
Anti-B antisera reagent reacts with
any B antigens present on the patient’s RBCs
42
Anti-D antisera reagent reacts with
any D antigens present on the patient’s RBCs
43
Is Rh control have a positive or negative reaction?
NEGATIVE
44
What happens if the Rh control is positive?
You must repeat the test
(Rh control with a positive result invalidates the current test)
45
What is needed for back type?
2 drops patient’s plasma + 1 drop red cell reagents
46
What does back type testing test for?
antibodies in the patient's plasma
47
A1 cell reagent reacts with
anti-A present in the patient’s plasma
48
B cell reagent reacts with
anti-B present in the patient’s plasma
49
What blood type is:
Front type: anti-A 4+, anti-B 0, anti-D 4+, Rh Control 0
Back type: A1 cells 0 and B cells 3+
A Positive
50
What blood type is:
Front type: anti-A 0, anti-B 4+, anti-D 0, Rh Control 0
Back type: A1 cells 3+ and B cells 0
B Negative
51
What blood type is:
Front type: anti-A 4+, anti-B 4+, anti-D 4+, Rh Control 0
Back type: A1 cells 0 and B cells 0
AB Positive
52
What blood type is:
Front type: anti-A 0, anti-B 0, anti-D 0, Rh Control 0
Back type: A1 cells 3+ and B cells 3+
O Negative
53
What is an ABO discrepancy?
the front and back type do NOT match
54
What MUST you do when you have an ABO discrepancy?
REPEAT the front and back type test
55
Can you give blood products when there is an ABO discrepancy?
NO
56
What blood product can you give when there is an emergency?
O (negative, unless low then positive for MALE PATIENTS and women OVER child bearing age)
57
If there are missing reactions in the Back Type, it is usually seen in...
Elderly (Abs are less reactive as we age), Newborns (Abs are made ~4 months old)
58
How do you resolve if there are missing reactions in the Back Type? Why?
1. Double the plasma in the back type
2. Incubate at room temperature for 5 minutes
Why:
We do this because ABO antibodies are IgM and tend to react better in the cold.
If the back type did not resolve after 5-15 minutes at room temperature you could stick it in the fridge at 4 degrees celcius.
59
What are examples of extra reactions in the back type?
Rouleaux, Cold IgM antibody, Subtype of Group A
60
What does Rouleaux look like?
stacked coins
61
How do you resolve rouleaux?
saline replacement technique
62
How do you resolve Cold IgM antibody?
prewarm technique
63
What can cause Cold IgM antibody?
anti-M, anti-N, anti-P, or a cold autoantibody
64
If there are Cold IgM antibody present, will you get a positive or negative antibody screen?
Patient will also have a positive antibody screen
65
What will the front type look like if there are subgroup A present?
A
66
How do you resolve an extra back type reaction caused by subtype group A?
Identify subtype group A by testing:
1. Patient RBCs against Anti-A1 lectin (Negative b/c no A1 antigens)
2. Patient plasma against A2 cells (Negative b/c A2 antigen is present, so no Anti-A2 in the patient plasma)
67
What is an extra reaction in the front type?
Acquired B antigen
68
What patients have Acquired B antigen?
1. Gram Negative Bacterial Infections
2. Colon Cancer
69
Can Acquired B antigen be resolved?
Yes, only if it is a Gram Negative Bacterial Infection.
If the Gram Negative Bacterial Infection is cured, the ABO discrepancy will also resolve.
70
Is Direct Antiglobulin Test (DAT) in vivo or in vitro?
In vivo, coating of red cells occur within patient’s body
71
DAT is an automatic reflex test to which positive test?
a Positive Antibody Screen
72
When is Direct Antiglobulin Test (DAT) ordered?
1. Every time the patient has a positive antibody screen
2. On cord specimens (to make sure baby’s cells aren’t being coated by mom’s antibodies)
73
What is tested first with a Direct Antiglobulin Test (DAT)?
polyspecific antihuman globulin (AHG)
74
If the polyspecific antihuman globulin (AHG) DAT test is positive, what do you do next?
You do DAT tests with monoclonal IgG, anti-c3bd, and saline
75
What does it mean when monoclonal IgG DAT test is positive?
antibodies are coating the RBCs
76
Why is IgG not read after a 5 minute room temperature incubation like poly, complement,
and saline?
You repeat the test
(the antibodies will dissociate/unbind from the antigen if sample w/ monoclonal IgG is left at room temp for 5 minutes)
77
What happens next, if the sample with monoclonal IgG for DAT is positive?
Must perform an acid elution to see which antibody is coating the cells
78
If anti-c3bd DAT is positive then...
there is complement coating the RBCs
79
Saline DAT acts like a control. Is it supposed to be positive or negative?
NEGATIVE
80
What can cause anti-c3bd DAT to be positive?
can be caused by certain medication/antibiotics
81
If the saline DAT testing turns out to be positive, what must you do next?
If positive must repeat DAT
82
What must you do when you perform or repeat a DAT test?
Always create a new 3-5% red cell suspension
83
Is Indirect Antiglobulin Test (IAT) in vivo or in vitro?
In vitro
84
What is in vitro?
Coating of red cells occurs within the lab by incubation at 37
85
When is Indirect Antiglobulin Test (IAT) ordered?
1. Weak D Testing
2. Antibody Screen
3. Antibody Identification (Panel)
86
What requires 37 degrees celsius incubation?
Indirect Antiglobulin Test (IAT)
87
Is Weak D Testing DAT or IAT?
IAT
88
Why can't you perform Weak D testing if they have a positive DAT test?
If a patient has a positive DAT test, then there is antibodies or complement coating the antigen. This will interfere with the ability to test for any D antigen. And they will instead be "Weak D indeterminate" and only will be given Rh negative units/
89
Why do you order Weak D testing?
performed to detect weak D and partial D patients
90
What is a Weak D individual?
have a normal D antigen but in fewer amounts on the RBCs
(basically less expression of the D antigen)
91
What is a Partial D individual?
have parts of the D antigen but are lacking the full D antigen
(They could make an antibody against the part of the D antigen that they are missing)
92
Are Screen testing DAT or IAT?
Indirect Antiglobulin Test (IAT)
93
What is Gel Screen?
IgM antibodies may cause mixed field reactions in the gel column
94
How does Gel Screen work?
Sometimes as the IgM begins to bind it may get too big to pass through the column. It gets stuck at the top causing a mixed field appearance
95
How do you read testing for screens using PEG enhancement?
Read MACROscopically at immediate spin (IS) and AHG
96
What tests need a 10-15 minute incubation at 37 degrees?
Screens using PEG enhancement
97
What tests need a 15-30 minute incubation at 37 degrees?
Screens using LO-ION
98
How do you read testing for screens using LO-ION?
Read MICROscopically at immediate spin (IS), 37 degrees incubation, and AHG
99
Who is a universal donor for blood?
O
100
Who is a universal receiver for plasma?
O
101
Who is a universal donor for plasma?
AB
102
Who is a universal receiver for blood?
AB
103
What can you do if you make too light of a 3-5% cell suspension?
If it’s too light then you can add more packed red blood cells.
104
What if it’s too dark of a 3-5% cell suspension?
If the suspension is too dark then you can add more saline OR spin down the suspension and remove some saline.
105
What is a method of testing in blood bank?
IAT
106
What is a specific test in blood bank?
DAT
107
Why must you perform an acid elution directly after a positive DAT IgG test?
The Direct Coombs Test only tells us that there is an antibody coating the cells. It can’t tell us which
antibody is coating the cells whereas the acid elution can.
108
In which situation would we perform a weak D test on a patient?
1. Newborns with Rh Negative Moms (most common)
2. Suspected Weak D or Partial D patients
109
What does this patient have:
Poly, 5'RT: w+
IgG: w+
C3bC3d, 5'RT: 0
Complement CC: 2+
Saline, 5'RT: 0
DAT positive for Polyspecific AHG and IgG antibodies
110
What does this patient have:
Poly, 5'RT: w+
IgG: 0
IgG CC: 2+
C3bC3d: 0
Complement 5'RT: w+
Saline, 5'RT: 0
DAT positive for Polyspecific AHG and Complement
111
What does this patient have:
Poly, 5'RT: w+
IgG: 0
IgG CC: 2+
C3bC3d: 1+
Complement 5'RT: 2+
Saline, 5'RT: 1+
Invalid, because the saline is positive
112
What is the Rh interpretation for:
anti-D: 0
Rh Control: 0
Weak D Test: 0
Weak D Rh Control: 0
Weak D check cells: 2+
Rh Control Check Cells: 2+
Rh negative
113
What is the Rh interpretation for:
anti-D: 0
Rh Control: 0
Weak D Test: w+
Weak D Rh Control: 0
Weak D check cells: n/a
Rh Control Check Cells: 2+
Rh positive
114
After examining no agglutination under the microscope the student adds Coombs Check Cells. There is still no agglutination after adding the check cells. What can
be one of the reasons there is no agglutination?
The student may have forgotten to add AHG which is why the check cells aren’t working
115
If the Coombs Check Cells (Coombs CC) have no agglutination, what do you do next?
Repeat test
116
If a 97 y/o woman has this, What is the problem? What does is the cause of the discrepancy?:
Anti-A: 4+
Anti-B: 0
Anti-D: 0
Rh Control: 0
A1 Cells: 0
B Cells: 0
1. ABO discrepancy with a lack of back type agglutination
2. Elderly people will have less reactive antibodies
117
If a 35 y/o man has this::
Anti-A: 4+
Anti-B: 0
Anti-D: 4+
Rh Control: 0
A1 Cells: 1+
B Cells: 4+
You perform a saline replacement technique on the back type but the A1 cells remain 1+.
What is the problem? What is the cause?
Extra back type reaction, the patient is most likely an A2 with an anti-A1. It can not be rouleaux since saline replacement did not resolve the discrepancy.
118
What IAT screen do you read at immediate spin, AHG and Check Cells?
PEG Screen
119
What IAT screen do you read macroscopically?
PEG Screen
120
What IAT screen do you read at immediate spin, 37 degrees, AHG, and Check Cells?
LO-ION Screen
121
What IAT screen do you read microscopically?
LO-ION Screen
122
If the type and screen is POSITIVE and they have a positive DAT test. What do you do next?
Acid Elution (Elulate)
123
If the type and screen is POSITIVE, what do you do next?
1. A direct coombs test
2. An antibody identification panel
3. Transfusion history on the patient/check if they've been pregnant in the past 90 days.
124
If the type and screen is POSITIVE and they have been pregnant in the past 90 days. What do you do next?
Check their antigen phenotype
125
What does the patient have:
Anti-A: 4+
Anti-B: 1+
Anti-D: 4+
Rh Control: 0
A1 Cells: 0
B Cells: 3+
Extra front type reaction: Acquired B antigen
126
What antibodies are IgM?
Lutheran (anti-Lua), MN (anti-M, anti-N), P (P bld grps),
127
What antibodies are IgG?
Rh, Kell, Duffy, Kidd, X, Lutheran (anti-Lub), S (anti-S, anti-s)
128
What is:
Immediate Spin 3+, 37 degrees 2+, AHG 0
IgM present
129
What is:
Immediate Spin 0, 37 degrees 0, AHG 2+
IgG present
130
What is:
Immediate Spin 0, 37 degrees 0, AHG 0, Check Cells 2+
No IgM or IgG
