Unit 3 Review Flashcards
1
Q
If a prospective blood donor has participated in a pheresis donation (platelets, plasma, granulocytes), atleast how much time must pass before he or she can donate whole blood?
A
48 hours
2
Q
A whole blood donor who has taken Tegison should be:
A
Permanently deferred
3
Q
What is the deferral period for a donor who has received a live attenuated vaccine for rubella?
A
4 weeks
4
Q
A women received a transfusion of packed RBCs while delivering her baby. Six months later she wanted to donate a unit of blood back to the American Red Cross. If the woman meets all the other criteria for donation, is she allowed to donate at this time?
A
No, she needs to wait 6 more months
5
Q
A patient who recently stopped taking clopidogrel (plavix) needs to donate platelets. How long must the patient defer donation after completing the medication?
A
14 days
6
Q
What is the minimum hemoglobin level for a potential allogeneic donor?
A
12.5 g/dL
7
Q
What is the minimum hemoglobin level for a potential autologous donor?
A
11 g/dL
8
Q
Which of the following is the only pheresis procedure that requires administration of a growth factor to the donor?
A
Leukopheresis
9
Q
A blood donor with a history of hepatitis B should be excluded:
A
Permanently
10
Q
An autologous unit should be donated what time period prior to the patients surgery/need?
A
72 hours
11
Q
The following blood donors regularly give blood. Which donor may donate on September 11th?
A
A 28 year old man who had plateletphersis on August 24th
12
Q
How many times can a person meeting all the optimal criteria donate an apheresis unit of platelets per year?
A
24 times
13
Q
A world traveler came in to do a directed donation for his sister when he found out she needed surgery for her hip? After spending 5 weeks in Europe, he traveled extensively throughout Africa. How should his case be handled?
A
He would not be able to donate, because all directed donors must meet the same criteria as allogenic donors
14
Q
Autologous blood donations may occur as:
A
- all of the above
- preoperative collection
- intraoperative collection
- postoperative collection
15
Q
Who is NOT included in the documentation process in the decision to use preoperative analogous blood?
A
Blood bank staff
16
Q
What is the last time a patient can donate for an autologous unit before surgery?
A
3 days before the scheduled surgery
17
Q
Which of the following tests is optional for the collection facility for an autologous donation?
A
Antibody screen
18
Q
Which of the following tests is not optimal for the transfusing facility for an autologous donation?
A
Group and type
19
Q
There is a decreased risk of each these when using autologous donations except:
A
Bacterial contamination
20
Q
For which of the following cases would intraoperative autologous collection NOT be contraindicated?
A
Cardiac surgery where there is no risk of contamination with clotting agents
21
Q
Blood product collections and component manufacturing, but not donor selection, is regulated by the:
A
CBER
22
Q
Which of the following accredits blood banks?
A
CAP
23
Q
A blood transfusion service is scheduled for an inspection. Which of the following agencies may be conducting the inspection?
A
- Any of these
- AABB
- CAP
- FDA
24
Q
Which of the following statement is true regarding directed donations?
A
Directed donations may need irradiation to prevent GVHD
25
Which of the following serologic tests is required for directed donations?
* All of these
- HepB
- HIV
- FTA
26
Donor arm preparation must be repeated if which of the following occurs?
* All of these occurrences
- the donor bends the arm
- the prepared site is touched with the fingers
- a nonsterile object comes in contact with the prepared site
27
When should mixing of the blood bag be performed?
Periodically during collection
28
How are pilot tubes for donor serologic testing collected?
- blood is collected from tubing connected to a needle in the donor’s arm
29
Nausea, twitching, and muscle spasm during blood donations are categorized as:
Mild reactions
30
Which of the following may be a sign of a potential fainting event?
*All of these
- sweating
- dizziness
- Pallor
31
A donor has fainted during blood collection. Which of the following is not an appropriate action?
Place warm compresses on the donors forehead
32
In addition to signs during a mild reaction to blood donation, a moderate reaction includes which of the following?
Loss of consciousness
33
Convulsions may occur during blood donation as a result of:
*Any of these
- cerebral ischemia
- epilepsy
- marked hyperventilation
34
Ensuring the presence of an adequate airway is most important in which type of blood donation reaction?
Severe reactions
35
Which statement concerning a hematoma is true?
A hemotoma is a localized collection of blood under the skin
36
Treating an occurrence of hematoma development during blood donation involves:
Removing the tourniquet and needle from donors arm
37
A 4-week deferral is required of donors exposed to which of these organisms?
Zika
38
An 8-week deferral is required of donors exposed to which of these organisms?
Ebola
39
A donor exposed to which of these organisms may be able to donate in as soon as 2 weeks?
Babesia
40
In order for a donor to be infected with West Nile Virus he/she must be bitten by a mosquito that has first bitten which reservoir host?
Birds
41
Which is the most economical way to test for West Nile Virus?
MP-NAT with follow up by ID-NAT on positives
42
A donor who was repeatedly reactive with anti-HBc may be considered for re-entry if after 8 weeks if which of these tests are negative?
* All of these
- HBsAg
- anti-HBc
- HBV NAT
43
Prions are:
Spongiform organisms that resist deactivation
44
Donors must be screened for which virus that causes a neurological disorder for myelopathy?
HTLV
45
Donors must be screened for which virus that causes a neurological disorder of myelopathy?
HTLV
46
How long is the donation deferral for persons who visit malaria-endemic countries?
3 years
47
Which of these countries is NOT a malaria-endemic country?
Austria
48
A U.S. military officer was deployed to Belgium from 1982 to 1985. How long is his deferment from blood donations once returning to the U.S?
Indefinitely
49
A 25 year old patient who had travelled to Ireland in the last year has been experiencing neurological abnormalties since returning to the U.S. several months ago. Which of the following is most likely?
- variant Creutzfeldt-Jakob disease with an accumulation of prion proteins
50
A 75 year old patient who had recently undergone a cornea transplant 6 months ago is suddenly experiencing neurological abnormalities. Which of the following is most likely?
Creutzfeldt-Jakob disease with no accumulation of prion proteins
51
A person infected with HIV-1 is diagnosed with AIDS-related condition (ARC). What antibodies will be present in the patients serum at this stage?
Anti-p24 and anti-gp41
52
The cytomegalovirus and Epstein-Barr virus belong to which family viruses?
Herpesviridae
53
American Association of Blood Bank (AABB) Standards mandate the donor of blood or a component given to a recipient who develops clinical or laboratory evidence of transfusion-associated hepatitis (TAH), HIV infection, or HTLV-I/II infection must be permanently deferred if the unit was:
The only unit transfused
54
The hepatitis C virus is thought to be included in which family?
Flaviviridae
55
HIV belongs to which family
Retroviridae
56
Why is transmission of cytomegalovirus (CMV) through blood components not a significant risk to most recipients?
most recipients are CMV-positive
57
How is the hepatitis A virus usually spread?
Oral-fecal route
58
A blood donors serological tests were reactive for HIV-1/2 antibodies. The test was repeated, and both were reactive. A Western blot confirmatory test was done and was negative. What is the protocol for this donor?
Unit is discarded
59
This disease can be transmitted through blood transfusion and is characterized by sponge-like lesions of the brain:
Creutzfeldt-Jakob disease
60
According to the Centers for Disease (CDC), and HIV-position person is considered to have AIDS according to what criterion?
Fewer than 200 CD4+ T cells per uL
61
Which two infections agents share the same vector?
Babesia and Borrelia
62
HBsAg is what part of the hepatitis B virus?
Coat protein
63
Which of the following parasites has not been associated with transmission via blood transfusion?
None of the above
64
In the HIV-I virus _______ is a core protein
P24
65
What is the causative agent for Rocky Mountain spotted fever?
Rickettsia Rickettsii
66
The hepatitis B virus belongs to which family?
Hepadnaviridae
67
Which test can reveal an asymptomatic patient with TAH?
ALT
68
What is treatment is recommended for chronic liver disease due to hepatitis C virus infection?
Alpha interferon
69
Which test for HIV infection depends on amplification of HIV integrated in the DNA of infected cells?
PCR
Polymerase chain reaction
70
What is the incubation period of hepatitis A virus in transfusion-associated hepatitis?
40-60 days
71
The hepatitis A virus belongs to which family of viruses?
Picornarviridae
72
Persons infected with the hepatitis C may develop what disease?
*All of the above
- chronic liver disease
- cirrhosis
- Hepatocellular carcinoma
73
Which of the following findings is not part of the typical pattern of hepatitis A infection?
Elevated ALT
74
The most sensitive test for the detection of HIV infection is the:
Polymerase chain reaction (PCR)
75
Which of the following findings is not part of the typical pattern of hepatitis A infection?
Elevated ALT
76
The most sensitive test for the detection of HIV infection is the:
Polymerase chain reaction (PCR)
77
Why are donors deferred for 6 months following receipt of blood products?
To permit adequate screening for transfusion-acquired viral infections
78
Which of the following statements regarding the Western Blot confirmation test for HIV infection is false?
Interpretation of test depends on upon degree of immunofluorescence
79
What marker usually is not detected when the hepatitis B-infected patient enters the convalescent phase?
HBeAg
80
Which of the following is indicated when a recipient of blood or blood components develops a viral disease?
Donor look back
81
Which of the following patients would at a greater risk for CMV infection?
An allogenic bone marrow transplant recipient
82
How can hepatitis A infection be prevented?
Superinfection by hepatitis D virus (HDV)
83
Which cell is invaded by the HIV viruses?
Lymphocyte
84
What is the course of hepatitis B immune globulin (HBIG)?
Persons with a high titer of anti-HBs
85
The “look-back” process includes notifying donors of abnormality with:
*All of the above
- predonation evaluation
- laboratory testing
- recipient follow-up
86
Which of the following in not included in the signs of symptoms of TAH?
Splenomegaly
87
In an individual infected with hepatitis B virus, which of the following is detected first?
HBsAg
88
Which statement regarding HDV is true?
HDV can occur simultaneously with hepatitis B virus
89
Pathogen inactivation intervention includes all of the except:
Millipore filtration
90
A single donor tested positive for HIV-1 via enzyme immunoassay screening techniques. The blood was retested and found to be nonreactive. What is the status of the donor whole blood unit?
Blood and components are okay for use
91
Which test is now used in the processing of all source plasmas for pathogen inactivation verification?
NAT
92
Lipid-enveloped viruses are inactivated by use of:
Detergents
93
The current risk of enveloped virus transmission is very low because of:
* A combination of all of the above
- heat treatment
- detergent treatment
- nanofiltration methods
94
Pathogen inactivation using psoralen activated by ultraviolet light is most effective in:
Platelet concentrates
95
Pathogen reduction systems may not be effective against which agents?
Prions
96
True or false? A person with acute hepatitis B infection is immune to infection from other hepatitis viruses
False
97
A whole blood donation contains a volume of 350 mL Which of the following is true regarding this unit?
FFP cannot be made from this unit
98
A unit of RBCs has an expiration date of 11/15/12. A patient currently on a fludarabine regimen requires irradiated packed RBCs. The unit is irradiated for this patient on 11/02/12. What is the correct expiration date postirradiation?
11/15/12
99
Packed RBCs must have a final hematocrit of less than or equal to:
80%
100
Leukoreduced packed RBCs must have an absolute WBC count of less than and contain at least what percent of original RBC mass?
5 x 10^8/80
101
All of the following statements are characteristic of a penetration cryoprotective agent except:
Osmotic fever prevents migration of water outside of the cell, preventing dehydration
102
What is the minimal pH required for platelets?
6.2
103
Cryoprecipitate is indicated for all of the following disorders except:
Hemophilia B
104
What does of RhIG would be appropriate for a D-negative woman who has had a miscarriage at 11 weeks gestation?
50 ug
105
A patient has a baseline platelet count of 30,000/uL. Upon receiving a platelet pool of 4 random platelets, what would you expect the post-transfusion platelet count to be?
50,000/uL
106
What is the expiration time for platelet concentrates that have been pooled?
4 hours
107
Which of the following are approved preservative solutions for blood storage at 1-6C for 21 days?
*All of the above
- ACD
- CPD
- CP2D
108
Methods of preparations of platelet concentrates from single units of whole blood must produce a product that yields a minimum of:
5.5 x 10^10 platelets per unit in 75% of units tested
109
Normally what percentage of 35 days old RBCs should be circulating 24 hours after transfusion?
70%
110
Which of the following statements explains why bacterial contamination of blood is rarely a problem?
* All of the above
111
What is the ratio of anticoagulant to whole blood in a unit of whole blood?
14 mL of anticoagulant-preservative for every 100 mL of whole blood collected
112
A unit of whole blood must be stored at what temperature?
1-6C
113
What is the shelf life of whole blood collected in acid-citrate-dextrose?
21 days
114
What is the shelf life of whole blood collected in citrate-phosphate-double dextrose?
21 days
115
What is shelf life of whole blood collected in citrate-phosphate-dextrose-adenine?
35 days
116
How are RBCs separated from whole blood?
* All of these
- apheresis
- centrifugation
- sedimentation
117
Within what time after collection of whole blood must RBCs be separated from whole blood in order for platelet and plasma components to be prepared?
8-24 hours
118
A unit of packed RBCs must be stored at what temperature?
1-6C
119
What is the shelf life of packed RBCs collected in acid-citrate-dextrose?
21 days
120
What are platelets obtained from apheresis donations called?s
Single-donor-platelets (SDPs)
121
Manufacturing RDPs is accomplished by using all of the following methods except:
Apheresis collection
122
A unit of packed platelets must be stored at what temperature?
20-24C
123
Units of platelets are stored under which of these conditions?
Constant agitation
124
What is the shelf-life of platelets if the unit is tested for bacterial contamination just prior to issuing?
7 days
125
What is the shelf-life of frozen RBCs?
10 years
126
Which of the following is/are an example of a penetrating cryoprotective agent?
Dimethylsulfoxide
127
A unit of cryopreserved RBCs must be stored below what temperature?
-65C
128
What is the expiration date of a deglycerolized unit of RBCs?
24 hours
129
Which statement about frozen plasma is correct?
The expiration of frozen plasma stored at -65C is 7 years
130
Frozen plasma is thawed at what temperature?
30-37C
131
Which statement about liquid plasma is correct?
*all of these are correct
- liquid plasma is a product from whole blood donations
- the expiration of liquid plasma 5 days after its whole blood shelf-life
- liquid plasma is stored at 1-6C
132
Liquid plasma is prepared from a unit of whole blood collected in CPDA-1 on July 28th. Water is the expiration date of this plasma?
- September 7th
133
A unit of granulocyte should contain at least what concentration of granulocytes?
1 x 10^10
134
A unit of granulocytes prepared on April 13th at 10:00 am and is irradiated at 2 PM the same day. What is the expiration date?
April 14th - 10:00 AM
135
Plasma factor concentrates are separated into various proteins by manipulating which variable?
* all of the above
- pH
- alcohol content
- temperature
136
Viruses are inactivated in units of plasma factor concentrate by all of these methods except:
Freezing
137
Which factor concentrate has almost completely replaced on cryotoprecipitate as the product of choice to treat patients with hemophilia A?
FVIII
138
Xenograhic forms of factor VIII are made from which source of plasma?
Porcine plasma
139
Which of the following is NOT considered in the preparation of Rho immunoglobulin?
Donors are Rh-(D) positive
140
Which of the following does NOT describe the preparation of NSA?
Plasma is fractioned using a warm alcohol process
141
Which of the following does NOT describe the preparation of immune serum globulin?
The solution of immune serum globulin is dehydrated state and must be reconstituted with saline
142
What is the half-life of immune serum globulin?
18-32 days
143
How is preparation of PPF different than that of NSA?
PPF contains less albumin and more globulins than NSA
144
What is the storage temperature for normal serum albumin ?
2-10C
145
What is the shelf-life for normal serum albumin?
5 years
146
what is the storage temperature for plasma protein fraction?
2-10C
147
What is the shelf-life for plasma protein fraction?
5 years
148
Which of the following does NOT describe the preparation of anti thrombin?
Apheresis of a single donor sensitized donor
149
In which animal has transgenic methods produced rAT in the milk?
Goats
150
Which of the following best describes the principle of the Kleihauer-Betke test??
D-positive indicator cells form rosettes around fetal Rh-positive RBCs
151
What tests are indicated for cord blood specimens if the mother has made anti-K?
ABO, Rh, antibody screen
152
Which of severe outcome can be caused by indirect bilirubin levels greater than 18 mg/dL in the newborn?
Bilirubinemia
153
All of the following are goals of an exchange transfusions except:
To correct anemia
154
Why is suppression of erythropoiesis an an advantage of exchange transfusions?
Decreases the risk of iron overload
155
Why is reverse grouping omitted in neonate ABO grouping?
Maternal antibodies mask the ABO antibodies of the neonate
156
A cord blood specimen from a jaundiced infant should be tested for which of the following?
*All of the above
- ABO
- DAT
- Rh
157
Why is the immediate spin eliminated in the prenatal antibody screen?
To reduce the detection of IgM antibodies
158
Which of the following reagents can be used to determine the immunoglobulin class of anti-M?
Chloroquine
159
All of the following are characteristics of ABO hemolytic disease of the fetus and newborn (HDFN)except;
The antibody is IgM
160
What is the physiological mechanism of Rh-immune globulin?
Attachment of fetal Rh-negative RBCs in maternal circulation, inhibiting production of anti0D
161
Which of the following treatments uses ultraviolet light to treat hyperbilirubinemia after the infant is delivered?
Aminocentesis
162
A 300 ug- dose of Rh-immune globulin contains sufficient anti-D to protect against how much whole blood?
100 mL
163
In HDFN, the IgG antibodies are direct against which antigen on the fetal RBC?
Viral
164
An O-positive mother gave birth to an A-negative baby. After 24 hours the newborns bilirubin level rose to 18 mg/dL. A DAT performed on the cord blood specimen was positive with polyspecific AHG and anti-IgG reagents. It is probable that ________ from maternal circulation is coating the newborns RBCs
Anti-B
165
Which RBC morphology is most characteristic in ABO HDFN and absent in Rh HDFN?
Microspherocytes
166
How is intrauterine transfusion performed?
RBCs are injected into the fetal peritoneal cavity
167
Immunization of the mother can be caused by a little as________ D-positive cavity
1 mL
168
Active immunization induced by Rh(D) antigen can be prevented by the concurrent administration of:
Alpha-1 protease inhibitor
169
Due to a short supply of O-negative packed cells, an Rh- negative patient was transfused with 1 unit of Rh- positive RBCs. Calculate the number of Rh-immune globulin vials needed to protect against 250 mL of Rh-positive packed cells
23
170
In order for the mother to be considered for Rh-immune globulin, her Rh type must be _______, and her newborn must be ________
Du-negative/Du-negative
171
What is the common clinical manifestation of ABO HDFN?
Hyperkalemia
172
Which of the following RBCs is appropriate for neonatal transfusion?
Group AB, CMV-negative
173
The laboratory is presented with a case of HDFN due to ABO incompatibility. The mother is Group O and the infant is group B. The most appropriate type of blood use for an exchange transfusion for this infant is:
B
174
The most important serologic test for the diagnosis of HDFN is the _____ with anti-IgG reagents
Elution
175
Which of the following antibodies path of indirect bilirubin produced as a result of RBC destruction in HDFN?
Anti-D
176
What is the physiological path of indirect bilirubin produced as a result of RBC destruction in HDFN?
Indirect bilirubin is transported across the placenta and excreted via maternal kidneys
177
All of the following are true regarding antibody titration of maternal IgG antibodies except:
RBCs should consist of the same genotype for each titration
178
The D-positive fetal cells in Rh-HDN are ________
Amorphic
179
Why is the Rh-positive firstborn of an Rh-negative mother unaffected by Rh hemolytic disease of the fetus and newborn (Rh HDFN)?
The plasma volume of the mother is tripled during the first pregnancy which dilutes anti-D
180
Besides the Rh antibodies, what other RBC antibody is common to cause severe HDFN?
Anti-Lea
181
The results of a Kleihauer-Betke stain indicate a fetomaternal bleed of 40 mL of whole blood. How many vials of Rh-immune globulin would be required?
2
182
What effect does ABO incompatibility between mother and fetus have on maternal sensitization to Rh antigen?
The chance of maternal sensitization to Rh antigen is decreased
183
Which of the following assays is used to calculate the amount of fetomaternal hemorrhage in a postpartum specimen?
Rosette test
184
In the event of a clinically significant antibody found in the mother’s serum, which of the following must be preformed to determine its concentration?
Elution
185
What is the cause of HDFN???
Destruction of the fetus’s RBCs by antibody by the mother
186
What immunoglobulin is capable of crossing the placenta?
IgG
187
What life-threatening disorder is characterized by a severe anemia, effusions, and ascites from hepatomegaly and splenomegaly?
Hydrosphere fetalis
188
What physiological phenomenon associates erytrhoblastosis fetalis with HDFN?
Release of nucleated RBCs into circulation of neonate inflicted with HDFN
189
In which type of HDFN is the firstborn affected?
ABO
190
Cannulation of the umbilical vein under ultrasound guidance is known as:
Cordocentesis
191
Why are premature newborns more likely to require exchange transfusions than full-term infants?
Premature newborn livers are loo underdeveloped to conjugate bilirubin
192
Blood transfusions to the fetus and premature infants should be _______ to prevent graft-versus-host disease
Gamma irradiated
193
Which IgG subclass carries more potency in RBCs hemolysis?
IgG3
194
Which of the following mother/infant blood types would be considered at risk for ABO hemolytic disease of fetus and newborn?
Mother is group O; baby is group B
195
When in the antenatal dose of Rh-immune globulin given?
28 weeks
196
Rh-immune globulin should be given within how many hours after delivery?
72
197
Which prenatal serologic tests are recommended during the first trimester?
*all of the above
- ABO
- Rh
- antibody screen
198
Anti-D in the serum of a third trimester pregnant woman with titer of 16 is indicative of:
Active immunization
199
How are units for exchange transfusion prepared?
Group O RBC and group AB plasma
200
Why does the rate of RBC destruction after birth decrease in an infant diagnosed with HDFN?
Maternal antibody is no longer entering infant circulation via the placenta
201
What is done to prevent HDFN caused by maternal anti-Jka antibody formation?
Monitor the mothers antibody level
202
What is the role of the technologist in the diagnosis and clinical management of HDFN?
Serological diagnosis of maternal alloimmunization
203
True or false? Rh-immune globulin is of no benefit after a person has been actively immunized and formed anti-D
True
204
True or False? The antibody titer of maternal antibody is directly proportional to severity of HDFN
False
205
All Rh-negative recipients who are transfused with as little as 1 mL of Rh-positive cells will develop ant-D
False
206
Which of the following can be found in warm autoimmune hemolytic anemia in the presence of hypoplastic marrow?
Reticulocytopenia
207
Most cases of warm autoimmune hemolytic anemia will be DAT-positive with which of the following ?
Both anti- IgG and Anti-C3d
208
Cold autoanti-H is more prevalent in which blood group?
A1B
209
RBCs sensitized in which drug-induced hemolytic anemia mechanism act as “innocent bystanders?”
Immune complex
210
Which drug can cause production of autoantibody?
Methyldopa
211
Which of the following is a proposed theory for methyldropa-induced mechanism of immune hemolytic anemia?
The drug affects the synthesis of IgG, exerting a direct effect on T lymphocytes, which results in a loss of suppressor function and subsequent proliferation of autoantibodies by B lymphocytes
212
In warm autoimmune hemolytic anemia, the autoantibody will frequently demonstrate__________ -like specificity
Rh
213
All of the following are clinical manifestations of cold hemoagglutinin disease (CHD) except:
Hepatosplenomegaly
214
A patient with a positive DAT needs go be phenotypes for Jka. what reagent can be used on RBCs to ensure accurate typing?
Chloroquine diphosphate
215
In which of the following is the DAT reactive with anti-C3d only?
Cold hemagglutiinin disease
216
Which of the following characterizes an alloimmune response in immune hemolytic anemia?
The patient produces anti-K to transfused RBCs
217
How can persons with CHD avoid hemolytic episodes?
Move to a warm climate
218
The onset of warm autoimmune hemolytic anemia (WAIHA) may be precipitated by:
* all of the above
- pregnancy
- bacterial infection
- trauma
219
In the digitonin-acid elution procedure, what is the purpose of adding phosphate buffer to the eluate solution?
To restore neutrality to the eluate
220
If a false-positive reaction was suspected with anti-D in the forward grouping due to the presence of a cold autoantibody, which of the following would show reactivity?
* All of above
- Du test
- DAT
- Rh control
221
Which of the following factors distinguishes a cold autoantibody produced in a patient with IM from that produced in a patient with pneumonia?
Anti-i specificity
222
Cold hemagglutinin disease represents what % of autoimmune hemolytic anemia (AIHA) cases?
18
223
In the case of an AB-positive individual, what test must be performed to ensure that a warm-reacting autoantibody is not causing false-positive reactions?
Rh control
224
Which of the following procedures can be used to resolve interference due to anti-I?
Cold autoabsorption and prewarm technique
225
How might a technologist detect a patient with drug-induced hemolytic anemia?
Positive DAT
226
In a patient who has been recently transfused, a positive DAT may be due to:
Alloantibody coating transfused donor cells
227
How is RBC destruction characterized in drug-induced immune HA via immune complex mechanism?
Intravascular hemolysis precipitated by complement activation
228
Anti-K was identified in absorbed serum of a patient with warm autoimmune hemolytic anemia. If a RBC phenotype was performed using an indirect antiglobulin test to ensure the patient was negative for antigen, what would the technologists find?
A positive result due to IgG coating cells
229
What technique can be used to ID an alloantibody in the presence of a cold autoagglutinin?
Prewarming
230
A patient with a warm reacting autoantibody needs 2 units of compatible, packed cells. Medical history reveals a blood transfusion 2 months ago. A homologous absorption is performed using the following RBC phenotype: R2R2, ss, Fy(a-b+), Jk(a+b-), kk. What alloantibody would remain in the serum after absorption?
Anti-S
231
Which of the following describes the drug-absorption (hapten) mechanism?
Drugs bind firmly to proteins of the RBC membrane
232
What is the most common drug associated with the drug-absorption mechanism?
Penicillin
233
What percentage of AIHA cases are caused by warm reacting autoantibodies?
70%
234
Why do clotted specimens yield positive DAT results with anti-C3 is the presence of a benign cold auto agglutinin?
Complement can be activated in Vitro
235
Approximately what percentage of AIHA cases are due to paroxysmal cold hemoglobinuria (PCH)?
1-2%
236
All of the following are classification of immune HA except:
Hyperimmune
237
What is one indication a positive DAT might be due to alloantibody coating donor RBCs?
Microscopic mixed-field appearance
238
What is the primary goal for treatment in patients with warm autoimmune HA?
Treat the underlying disease
239
Autoanti-I was identified in a patient transfused 1 month ago. Which technique is advocated to detect alloantibodies in this patient?
Prewarming
240
A cold antibody titer greater than______ at 4C is characteristic of pathological CHD
1,000
241
Persons diagnosed with pneumonia caused by Mycoplasma pneumonia may produce a cold autoantibody with _______ specificity
Anti-I
242
Which alloantibody is frequently present in the serum of i adults?
Anti-I
243
A benign cold autoagglutinin may cause interference in antibody screening procedures when:
Polyspecific AHG reagents are used in the test procedure
244
Which of the following is a characteristic RBC morphology seen on a peripheral blood smear from a patient with warm autoimmune HA?
Spherocytes
245
How is the serology workup for an autoantibody produced by a drug-induced hemolytic anemia different from other autoantibody workups?
The antibody will only be reactive with RBCs in the presence of the drug
246
Which of the following describes a cold autologous absorption procedure?
An aliquot of patient cells is incubated with an equal aliquot of patient serum at 4C autoantibody is removed while alloantibody remains in the serum
247
What treatment for warm autoimmune hemolytic anemia aids in the reduction of antibody and removes a potent site of RBC damage and destruction?
Splenectomy
248
Which of the following signifies intravascular hemolysis in AIHA?
Hemoglobinuria
249
A 5-year old boy suffering from the measles complained of back pain, chills, and stomach pain. A visit to the doctor revealed hemoglobinuria, bilirubinemia, and hemoglobinemia. The child’s Hb level had fallen to 6 g/dL. A Donath-Landsteiner test was performed and showed the following: control sample = no hemolysis; test sample = hemolysis. The results are consistent with what disorder?
Paroxysmal cold hemoglobinuria
250
In which case might you see an anti-i?
Mononucleosis
251
Which of the following forward-typing reagents may generate false-positive results in a patient with a warm-reacting autoantibody?
Anti-D
252
What is the recommended treatment for drug-induced hemolytic anemia caused by the immune complex mechanism?
Cessation of drug administration
253
Immune hemolytic anemia is defined as:
A shortened RBC survival mediated through humoral antibody production
254
What reagent cell type is used in the immune complex formation test to detect drug-anti drug interaction?
Group O
255
What is the most frequent antibody specificity in CHD?
Anti-I
256
Chemically modified anti-D reacted negatively in a patient with a warm-reacting autoantibody. A Du test was performed using monospecific IgG, which was positive in Coombs phase. A fetal screen (rosette test) was also performed on this patient and showed no rosettes when viewed microscopically. based on these results, what is the correct Rh type of this patient?
Rh-negative
257
Which of the following is a characteristic of autoantibodies?
Antibody reacts with high-incidence antigens
258
All of the following are characteristics of benign cold autoagglutinin except:
Antibodies have a titer greater than 64 at 4 C
259
Which cells contain the most i antigen?
Cord blood
260
Which theory supports production of autoantibodies?
Loss of T-cell suppressor activity upon self-antigens leads to production of autoantibody
261
How can cold autoantibody interference with ABO grouping be avoided?
Washing cells with normal saline warmed to 37C
262
In cases of warm autoimmune hemolytic anemia, what subclass of IgG is most efficient in binding complement?
IgG3
263
Which of the following regarding the immune complex mechanism is serologic testing is true?
The DAT will be positive with monospecific C3 but negative with IgG
264
Which drug-induced mechanism does not result in a hemolytic episode?
Membrane modification
265
What is the mechanism by which thiol reagents, such as DTT, disperse agglutination caused by cold-reactive autoantibody?
Cleavage of the intersubunit disulfide bonds of pentameric IgM molecules
266
A 28 year old female with cold hemagglutinin disease has a positive DAT. When the DAT is repeated using monospecific reagent, which of the following is most likely to be detected?
IgM
267
The antigen I is often:
Absent on all cord cells
268
An EDTA sample is preferred over a clotted sample for performing DAT testing because:
The EDTA prevents complement binding in-vitro
269
A DAT was performed on a patient suspected of having autoimmune HA. The following results were obtained. PS AHG 3+, Anti-IgG 2+, Anti-C3d-negative. These results mean:
The patients cells are coated with IgG
270
Cold panel results obtained are:
A1 cells: 4+
A2 cells: 4+
O cells: 4+
O cord cells: 0
These results suggest which antibody?
I
271
Approximately what percentage of warm autoimmune HA will produce a positive DAT with both IgG and C3d antibodies?
67%
