問題一覧
1
When the red cells of an individual fail to react with anti-U, they usually fail to react with: anti-M anti-Le anti-S anti-Py
anti-S
2
Which of the following red cell antigens are found on glycophorin-A? M,N Le^a, Le^b S,s P1P1, Pk
M,N
3
Paroxysmal cold hemoglobinuria (PCH) is associated with antibody specificity toward which of the following? a Kell system antigens b Duffy system antigens c P antigen d l antigen
c P antigen
4
Which of the following is a characteristic of anti-i? a associated with warm autoimmune hemolytic anemia b found in the serum of patients with infectious mononucleosis c detected at lower temperatures in the serum of normal individuals d found only in the serum of group O individuals
b found in the serum of patients with infectious mononucleosis
5
In a case of cold autoimmune hemolytic anemia, the patient’s serum would most likely react 4+ at immediate spin with: group A cells, B cells and O cells, but not his own cells cord cells but not his own or other adult cells all cells of a group O cell panel and his own cells only penicillin-treated panel cells, not his own cells
all cells of a group O cell panel and his own cells
6
Cold agglutinin syndrome is associated with an antibody specificity toward which of the following? a Fy:3 b P c I d Rh:1
c I
7
Which of the following is a characteristic of anti-i? often associated with hemolytic disease of the newborn reacts best at room temperature or 4°C reacts best at 37°C is usually IgG
reacts best at room temperature or 4°C
8
The Kell (K1) antigen is: a absent from the red cells of neonates b strongly immunogenic c destroyed by enzymes d has a frequency of 50% in the random population
b strongly immunogenic
9
In chronic granulomatous disease (CGD), granulocyte function is impaired. An association exists between this clinical condition and a depression of which of the following antigens? Rh P Kell Duffy
Kell
10
The antibodies of the Kidd blood group system: react best by the indirect antiglobulin test are predominantly IgM often cause allergic transfusion reactions do not generally react with antigen-positive, enzyme-treated RBCs
react best by the indirect antiglobulin test
11
Proteolytic enzyme treatment of red cells usually destroys which antigen? a Jk^a b E c Fy^a d k
c Fy^a
12
Anti-Fy^a is: usually a cold-reactive agglutinin more reactive when tested with enzyme-treated red blood cells capable of causing hemolytic transfusion reactions often an autoagglutinin
capable of causing hemolytic transfusion reactions
13
Resistance to malaria is best associated with which of the following blood groups? a Rh b I/i c P d Duffy
d Duffy
14
What percent of group O donors would be compatible with a serum sample that contained anti-X and anti-Y if X antigen is present on red cells of 5 of 20 donors, and Y antigen is present on red cells of 1 of 10 donors? a 2.5 b 68 c 25.0 d 68.0
d 68.0
15
How many Caucasians in a population of 100,000 will have the following combination of phenotypes? a 1 b 14 c 144 d 1,438
d 1,438
16
What is the approximate probability of finding compatible blood among random Rh-positive units for a patient who has anti-c and anti-K? (Consider that 20% of Rh-positive donors lack c and 90% lack K) 1% 10% 18% 45%
18%
17
A 25-year-old Caucasian woman, gravida 3, para 2, required 2 units of Red Blood Cells. The antibody screen was positive and the results of the antibody panel are shown below:
d
18
Aman suffering from gastrointestinal bleeding has received 20 units of Red Blood Cells in the last 24 hours and is still oozing post-operatively. The following results were obtained: What blood product should be administered? a Fresh Frozen Plasma b Red Blood Cells c Factor VIII Concentrate d Platelets
a Fresh Frozen Plasma
19
Transfusion of which of the following is needed to help correct hypofibrinogenemia due to DIC? Whole Blood Fresh Frozen Plasma Cryoprecipitated AHF Platelets
Cryoprecipitated AHF
20
blood component used in the treatment of hemophilia A is: Factor VIII Concentrate Fresh Frozen Plasma Platelets Whole Blood
Factor VIII Concentrate
21
Which of the following blood components is most appropriate to transfuse to an 8-year-old male hemophiliac who is about to undergo minor surgery? Cryoprecipitated AHF Red Blood Cells Platelets Factor VIII Concentrate
Factor VIII Concentrate
22
A unit of Fresh Frozen Plasma was inadvertently thawed and then immediately refrigerated at 4°C on Monday morning. On Tuesday evening this unit may still be transfused as a replacement for: a_ all coagulation factors b Factor V ec Factor VIII d Factor IX
d Factor IX
23
A newborn demonstrates petechiae, ecchymosis and mucosal bleeding. The preferred blood component for this infant would be: a Red Blood Cells b Fresh Frozen Plasma c Platelets d Cryoprecipitated AHF
c Platelets
24
Which of the following would be the best source of Platelets for transfusion in the case of alloimmune neonatal thrombocytopenia? a father b mother c pooled platelet-rich plasma d polycythemic donor
b mother
25
An obstetrical patient has had 3 previous pregnancies. Her first baby was healthy, the second was jaundiced at birth and required an exchange transfusion, while the third was stillborn. Which of the following is the most likely cause? a ABO incompatibility b immune deficiency disease c congenital spherocytic anemia d Rh incompatibility
d Rh incompatibility
26
A specimen of cord blood is submitted to the transfusion service for routine testing. The following results are obtained: It is known that the father is group B, with the genotype of cde/cde. Of the following 4 antibodies, which 1 is the most likely cause of the positive direct antiglobulin test? a anti-A b anti-D ¢ anti-c d anti-C
¢ anti-c
27
ABO-hemolytic disease of the newborn: a usually requires an exchange transfusion b most often occurs in first born children c frequently results in stillbirth d is usually seen only in the newborn of group O mothers
d is usually seen only in the newborn of group O mothers
28
Which of the following antigens is most likely to be involved in hemolytic disease of the newborn? a Le^a b P1 c M d Kell
d Kell
29
ABO hemolytic disease of the fetus and newborn (HDFN) differs from Rh HDFN in that: a Rh HDFN is clinically more severe than ABO HDFN b the direct antiglobulin test is weaker in Rh HDFN than ABO c RhHODEN occurs in the first pregnancy d_ the mother’s antibody screen is positive in ABO HDN
a Rh HDFN is clinically more severe than ABO HDFN
30
The following results were obtained: Which of the following is the most probable explanation for these results? a ABO hemolytic disease of the fetus and newborn b Rh hemolytic disease of the fetus and newborn; infant has received intrauterine transfusions c Rhhemolytic disease of the fetus and newborn, infant has a false-negative Rh typing d large fetomaternal hemorrhage
c Rhhemolytic disease of the fetus and newborn, infant has a false-negative Rh typing
31
A group A, Rh-positive infant of a group O, Rh-positive mother has a weakly positive direct antiglobulin test and a moderately elevated bilirubin 12 hours after birth. The most likely cause is: a ABO incompatibility b Rh incompatibility c blood group incompatibility due to an antibody to a low frequency antigen d neonatal jaundice not associated with blood group
a ABO incompatibility
32
In suspected cases of hemolytic disease of the newborn, what significant information can be obtained from the baby’s blood smear? a estimation of WBC, RBC, and platelet counts b marked increase in immature neutrophils (shift to the left) c a differential to estimate the absolute number of lymphocytes present d_ determination of the presence of spherocytes
d_ determination of the presence of spherocytes
33
The Liley method of predicting the severity of hemolytic disease of the newborn is based on the amniotic fluid: a_ bilirubin concentration by standard methods b change in optical density measured at 450 nm ¢ Rh determination d ratio of lecithin to sphingomyelin
b change in optical density measured at 450 nm
34
These laboratory results were obtained on maternal and cord blood samples: mother: A- baby: AB+, DAT: 3+ cord hemoglobin: 10 g/dL (100 g/L) Does the baby have HDN? a no, as indicated by the cord hemoglobin b yes, although the cord hemoglobin is normal, the DAT indicates HDN ¢ yes, the DAT and cord hemoglobin level both support HDN d_ no, a diagnosis of HDN cannot be established without cord bilirubin levels
¢ yes, the DAT and cord hemoglobin level both support HDN
35
The main purpose of performing antibody titers on serum from prenatal immunized women is to: a determine the identity of the antibody b identify candidates for amniocentesis or percutaneous umbilical blood sampling c decide if the baby needs an intrauterine transfusion d_ determine if early induction of labor is indicated
b identify candidates for amniocentesis or percutaneous umbilical blood sampling
36
Which unit should be selected for exchange transfusion if the newborn is group A, Rh-positive and the mother is group A, Rh-positive with anti-c? a A, CDe/CDe b A, cDE/cDE c O,cde/cde d A, cde/cde
a A, CDe/CDe
37
A mother is group A, with anti-D in her serum. What would be the preferred blood product if an intrauterine transfusion is indicated? a O, Rh-negative Red Blood Cells b O, Rh-negative Red Blood Cells, Irradiated c A, Rh-negative Red Blood Cells d A, Rh-negative Red Blood Cells, Irradiated
b O, Rh-negative Red Blood Cells, Irradiated
38
Laboratory studies of maternal and cord blood yield the following results: Maternal blood Cord blood O, Rh-negative B, Rh-positive anti-E in serum DAT = 2+ anti-E in eluate If exchange transfusion is necessary, the best choice of blood is: a _ B, Rh-negative, E+ b_ B, Rh-positive, E+ c_ O, Rh-negative, Ed O, Rh-positive, E
d O, Rh-positive, E
39
A blood specimen from a pregnant woman is found to be group B, Rh-negative and the serum contains anti-D with a titer of 512. What would be the most appropriate type of blood to have available for a possible exchange transfusion for her infant? O, Rh-negative O, Rh-pasitive B, Rh-negative B, Rh-positive
O, Rh-negative
40
Blood selected for exchange transfusion must: a_ lack red blood cell antigens corresponding to maternal antibodies b be <3 days old c be the same Rh type as the baby d be ABO compatible with the father
a_ lack red blood cell antigens corresponding to maternal antibodies
41
When the main objective of an exchange transfusion is to remove the infant’s antibody-sensitized red blood cells and to control hyperbilirubinemia, the blood product of choice is ABO compatible: Fresh Whole Blood Red Blood Cells (RBC) washed RBC suspended in Fresh Frozen Plasma heparinized Red Blood Cells
RBC suspended in Fresh Frozen Plasma
42
To prevent graft-vs-host disease, Red Blood Cells prepared for infants who have received intrauterine transfusions should be: a saline-washed b irradiated c frozen and deglycerolized d group- and Rh-compatible with the mother
b irradiated
43
Which of the following is the preferred specimen for the initial compatibility testing in exchange transfusion therapy? a maternal serum b eluate prepared from infant’s red blood cells ¢ paternal serum d infant’s postexchange serum
a maternal serum
44
Rh-Immune Globulin is requested for an Rh-negative mother who has the following results: What is the most likely explanation? a mother is a genetic weak D b mother had a fetomaternal hemorrhage of D+ cells ¢« mother’s red cells are coated weakly with IgG d anti-D reagent is contaminated with an atypical antibody
b mother had a fetomaternal hemorrhage of D+ cells
45
The following results are seen on a maternal postpartum sample: The most appropriate course of action is to: a report the mother as Rh-negative b report the mother as Rh-positive ¢ perform an elution on mother’s RBCs d investigate for a fetomaternal hemorrhage
d investigate for a fetomaternal hemorrhage
46
What is the most appropriate interpretation for the laboratory data given below when an Rh-negative woman has an Rh-positive child? Rosette fetal screen using enzyme-treated D+ cells mother’s sample: 1 rosette/3 fields positive control: 5 rosettes/3 fields negative control: no rosettes observed Mother is not a candidate for Rhlg mother needs 1 vial of Rhlg mother needs 2 vials of Rhlg the fetal-maternal hemorrhage needs to be quantitated
Mother is not a candidate for Rhlg
47
Refer to the following information: What is the best interpretation for the laboratory data given above? a mother is Rh-positive b mother is weak D+ ¢ mother has had a fetal-maternal hemorrhage d mother has a positive DAT
¢ mother has had a fetal-maternal hemorrhage
48
a weakly reactive anti-D is detected in a postpartum specimen from an Rh-negative woman. During her prenatal period, all antibody screening tests were negative. These findings indicate: a_ that she is a candidate for Rh immune globulin b that she is not a candidate for Rh immune globulin c a need for further investigation to determine candidacy for Rh immune globulin d_ the presence of Rh-positive cells in her circulation
c a need for further investigation to determine candidacy for Rh immune globulin
49
Th e results of a Kleihauer-Betke stain indicate a fetomaternal hemorrhage of 35 mL of whole blood. How many vials of Rh immune globulin would be required? a 1 b 2 c 3 d 4
b 2
50
fetomaternal hemorrhage of 35 mL of fetal Rh-positive packed RBCs has been detected in an Rh-negative woman. How many vials of Rh immune globulin should be given? 0 1 2 3
3
51
Criteria determining Rh immune globulin eligibility include: mother is Rh-positive infant is Rh-negative mother has not been previously immunized to the D antigen infant has a positive direct antiglobulin test
mother has not been previously immunized to the D antigen
52
hile performing routine postpartum testing for an Rh immune globulin (RhIG) candidate, a weakly positive antibody screening test was found. Anti-D was identified. This antibody is most likely the result of: a massive fetomaternal hemorrhage occurring at the time of this delivery b antenatal administration of Rh immune globulin at 28 weeks gestation ¢ contamination of the blood sample with Wharton jelly d_ mother having a positive direct antiglobulin test
b antenatal administration of Rh immune globulin at 28 weeks gestation
53
Rh immune globulin administration would not be indicated in an Rh-negative woman who has a(n): first trimester abortion husband who is Rh-positive anti-D titer of 1:4,096 positive direct antiglobulin test
anti-D titer of 1:4,096
54
A Kleihauer-Betke stain of a postpartum blood film revealed 0.3% fetal cells. What is the estimated volume (mL) of the fetomaternal hemorrhage expressed as whole blood? 5 15 25 35
25
55
Based upon Kleihauer-Betke test results, which of the following formulas is used to determine the volume of fetomaternal hemorrhage expressed in mL of whole blood? % of fetal cells present x 30 % of fetal cells present x 50 % of maternal cells present x 30 % of maternal cells present x 50
% of fetal cells present x 50
56
An acid elution stain was made using a 1-hour post-delivery maternal blood sample. Out of 2,000 cells that were counted, 30 of them appeared to contain fetal hemoglobin. It is the policy of the medical center to add 1 vial of Rh immune globulin to the calculated dose when the estimated volume of the hemorrhage exceeds 20 mL of whole blood. Calculate the number of vials of Rh immune globulin that would be indicated under these circumstances. a 2 b 3 c 4 d 5
c 4
57
The rosette test will detect a fetomaternal hemorrhage (FMH) as small as: a 10mL b 15mL c 20mL d 30 mL
a 10mL
58
A10 mL fetal maternal hemorrhage in an Rh-negative woman who delivered an Rh-positive baby MLS ony means that the: mother’s antibody screen will be positive for anti-D rosette test will be positive mother is not a candidate for Rh immune globulin mother should receive 2 doses of Rh immune globulin
rosette test will be positive
59
Mixed leukocyte culture (MLC) is a biclogical assay for detecting which of the following? HLA-A antigens HLA-B antigens HLA-D antigens immunoglobulins
HLA-D antigens
60
A 40-year-old man with autoimmune hemolytic anemia due to anti-E has a hemoglobin level of 10.8 g/dL (108 g/L). This patient will most likely be treated with: a Whole Blood b Red Blood Cells c Fresh Frozen Plasma d no transfusion
d no transfusion
61
patient in the immediate post bone marrow transplant period has a hematocrit of 21%. The red cell product of choice for this patient would be: packed saline washed microaggregate filtered irradiated
irradiated
62
HLA antigen typing is important in screening for: ABO incompatibility a kidney donor Rh incompatibility a blood donor
a kidney donor
63
DR antigens in the HLA system are: expressed on platelets expressed on granulocytes significant in organ transplantation not detectable in the lymphocytotoxicity test
expressed on platelets
64
Anti-E is identified in a panel at the antiglobulin phase. When check cells are added to the tubes, no agglutination is seen. The most appropriate course of action would be to: quality control the AHG reagent and check cells and repeat the panel open a new vial of check cells for subsequent testing that day open a new vial of AHG for subsequent testing that day record the check cell reactions and report the antibody panel result
quality control the AHG reagent and check cells and repeat the panel
65
A serological centrifuge is recalibrated for ABO testing after major repairs. Given the data above, the centrifuge time for this machine should be: a 15 seconds b 20 seconds c 25 seconds d 30 seconds
b 20 seconds
66
Which of the following represents an acceptably identified patient for sample collection and transfusion? a a handwritten band with patient’s name and hospital identification number is affixed to the patient's leg b_ the addressographed hospital band is taped to the patient’s bed ¢ anunbanded patient responds positively when his name is called d_ the chart transported with the patient contains his armband not yet attached
a a handwritten band with patient’s name and hospital identification number is affixed to the patient's leg
67
Samples from the same patient were received on 2 consecutive days. Test results are summarized below: How should the request for crossmatch be handled? a crossmatch A, Rh-positive units with sample from day 1 b crossmatch B, Rh-positive units with sample from day 2 ¢ crossmatch AB, Rh-positive units with both samples d collect anew sample and repeat the tests
d collect anew sample and repeat the tests
68
The following test results are noted for a unit of blood labeled group A, Rh-negative: Cells tested with: anti-A anti-B anti-D 4+ 0 3+ What should be done next? a transfuse as a group A, Rh-negative b transfuse as a group A, Rh-positive ¢ notify the collecting facility d discard the unit
¢ notify the collecting facility
69
What information is essential on patient blood sample labels drawn for compatibility testing? a_ biohazard sticker for AIDS patients b patient’s room number ¢ unique patient medical number d_ phiebotomist initials
¢ unique patient medical number
70
Granulocytes for transfusion should: a_ be administered through a microaggregate filter b be ABO compatible with the recipient’s serum c be infused within 72 hours of collection d never be transfused to patients with a history of febrile transfusion reactions
b be ABO compatible with the recipient’s serum
71
A neonate will be transfused for the first time with group O Red Blood Cells. Which of the following is appropriate compatibility testing? crossmatch with mother’s serum crossmatch with baby’s serum no crossmatch is necessary if initial plasma screening is negative no screening or crossmatching is necessary for neonates
no crossmatch is necessary if initial plasma screening is negative
72
A group B, Rh-negative patient has a positive DAT. Which of the following situations would occur? a_ all major crossmatches would be incompatible b the weak D test and control would be positive c_ the antibody screening test would be positive d_ the forward and reverse ABO groupings would not agree
b the weak D test and control would be positive
73
‘The following reactions were obtained: Cells tested with: Serum tested with: anti-A anti-B anti-A,B A1 cells B cells 4+ 3+ 4+ 1+ 4+ The technologist washed the patient’s cells with saline, and repeated the forward typing. A saline replacement technique was used with the reverse typing. The following results were obtained: Cells tested with: Serum tested with: anti-A anti-B anti-A,B A1 cells Bcells 4+ 0 4+ 0 A+ The results are consistent with: a acquired immunodeficiency disease b Bruton agammaglobulinemia c multiple myeloma d acquired “B” antigen
c multiple myeloma
74
What is the most likely cause of the following ABO discrepancy? Patient's cells vs: Patient’s serum vs: anti-A anti- B A1 cells B cells 0 0 0 0 recent transfusion with group O blood antigen depression due to leukemia false-negative cell typing due to rouleaux obtained from a heel stick of a 2-month old baby
obtained from a heel stick of a 2-month old baby
75
Which of the following patient data best reflects the discrepancy seen when a person’s red cells demonstrate the acquired-B phenotype? Forward grouping Reverse grouping patient A B O patient B AB A patient C O B patient D B AB a A b B c C d D
b B
76
Which of the following is characteristic of Tn polyagglutinable red cells? if group O, they may appear to have acquired a group A antigen they show strong reactions when the cells are enzyme-treated they react with Arachis hypogaea lectin the polyagglutination is a transient condition
if group O, they may appear to have acquired a group A antigen
77
Mixed field agglutination encountered in ABO grouping with no history of transfusion would most likely be due to: a Bombay phenotype (Oh) b T activation c A3 red cells d_ positive indirect antiglobulin test
c A3 red cells
78
Which of the following is a characteristic of polyagglutinable red cells? can be classified by reactivity with Ulex europaeus are agglutinated by most adult sera are always an acquired condition autocontrol is always positive
are agglutinated by most adult sera
79
Consider the following ABO typing results: What is the most likely cause of this discrepancy? a Aj with anti-A; b cold alloantibody ¢ cold autoantibody d acquired-A phenomenon
¢ cold autoantibody
80
Consider the following ABO typing results: What should be done next? a test serum against a panel of group O cells b neutralization c perform serum type at 37°C d elution
c perform serum type at 37°C
81
The following results were obtained on a patient’s blood sample during routine ABO and Rh testing: Cell testing: Serum testing: anti-A: 0 A1 cells: 4+ anti-B: 4+ B cells: 2+ anti-D: 0) autocontrol: 0 Select the course of action to resolve this problem: a draw a new blood sample from the patient and repeat all test procedures b test the patient’s serum with Ap cells and the patient’s red cells with anti-A, lectin ¢ repeat the ABO antigen grouping using 3x washed saline-suspended cells d perform antibody screening procedure at immediate spin using group O cells
d perform antibody screening procedure at immediate spin using group O cells
82
Which of the following explains an ABO discrepancy caused by problems with the patient’s red blood cells? a an unexpected antibody b rouleaux c agammaglobulinemia d Tn activation
d Tn activation
83
‘The test for weak D is performed by incubating patient’s red cells with: a_ several different dilutions of anti-D serum b anti-D serum followed by washing and antiglobulin serum c anti-Du serum d antiglobulin serum
b anti-D serum followed by washing and antiglobulin serum
84
Refer to the following data: Forward group: Reverse group: anti-A anti-B anti-A, lectin 4+ 0 4+ Which of the following antibody screen results would you expect with the ABO discrepancy seen above? a negative b positive with all screen cells at the 37°C phase c positive with all screen cells at the RT phase; autocontrol is negative d positive with all screen cells and the autocontrol cells at the RT phase
c positive with all screen cells at the RT phase; autocontrol is negative
85
The following results were obtained when testing a sample from a 20-year-old, first-time blood donor: Forward group: Reverse group: anti-A anti-B A1 cells B cells 0) 0 0 3+ What is the most likely cause of this ABO discrepancy? a_ loss of antigen due to disease b acquired B c phenotype Oh “Bombay” d weak subgroup of A
weak subgroup of A
86
A mother is Rh-negative and the father Rh-positive. Their baby is Rh-negative. It may be concluded that: the father is homozygous for D the mother is heterozygous for D the father is heterozygous for D at least 1 of the 3 Rh typings must be incorrect
the father is heterozygous for D
87
Some blood group antibodies characteristically hemolyze appropriate red cells in the presence of: a complement b anticoagulants c preservatives d penicillin
a complement
88
Review the following schematic diagram: PATIENT SERUM + REAGENT GROUP “O” CELLS INCUBATE —> READ FOR AGGLUTINATION WASH — ADD AHG — AGGLUTINATION OBSERVED ‘The next step would be to: a add “check cells” as a confirmatory measure b identify the cause of the agglutination c perform an elution technique d_ perform a direct antiglobulin test
b identify the cause of the agglutination
89
The following results were obtained in pretransfusion testing: 37°C 1AT screening cell | 0 3+ screening cell Il 0 3+ autocontrol 0 3+ The most probable cause of these results is: a rouleaux b a warm autoantibody c acold autoantibody d multiple alloantibodies
b a warm autoantibody
90
patient is typed as group O, Rh-positive and crossmatched with 6 units of blood. At the indirect antiglobulin (IAT) phase of testing, both antibody screening cells and 2 crossmatched units are incompatible. What is the most likely cause of the incompatibility? recipient alloantibody recipient autoantibody donors have positive DATs rouleaux
recipient alloantibody
91
Refer to the following data: Which clinical condition is consistent with the lab results shown above? a cold hemagglutinin disease b warm autoimmune hemolytic anemia c penicillin-induced hemolytic anemia d delayed hemolytic transfusion reaction
b warm autoimmune hemolytic anemia
92
A patient received 2 units of Red Blood Cells and had a delayed transfusion reaction. Pretransfusion antibody screening records indicate no agglutination except after the addition of IgG sensitized cells. Repeat testing of the pretransfusion specimen detected an antibody at the antiglobulin phase. What is the most likely explanation for the original results? red cells were overwashed centrifugation time was prolonged patient’s serum was omitted from the original testing antiglobulin reagent was neutralized
patient’s serum was omitted from the original testing
93
At the indirect antiglobulin phase of testing, there is no agglutination between patient serum and screening cells. One of 3 donor units was incompatible. The most probable explanation for these findings is that the: a patient has an antibody directed against a high incidence antigen b patient has an antibody directed against a low incidence antigen c donor has an antibody directed against donor cells d donor has a positive antibody screen
b patient has an antibody directed against a low incidence antigen
94
The major crossmatch will detect a(n): a group A patient mistyped as group O b unexpected red cell antibody in the donor unit c Rh-negative donor unit mislabeled as Rh-positive d recipient antibody directed against antigens on the donor red cells
d recipient antibody directed against antigens on the donor red cells
95
A 42-year-old female is undergoing surgery tomorrow and her physician requests that 4 units of Red Blood Cells be crossmatched. The following results were obtained: What is the most likely cause of the incompatibility of donor 1? a single alloantibody b multiple alloantibodies c Rh incompatibilities d donor 1 has a positive DAT
a single alloantibody
96
Which of the following would most likely be responsible for an incompatible antiglobulin crossmatch? a recipient’s red cells possess a low frequency antigen b anti-K antibody in donor serum ¢ recipient’s red cells are polyagglutinable d donor red cells have a positive direct antiglobulin test
d donor red cells have a positive direct antiglobulin test
97
A reason why a patient’s crossmatch may be incompatible while the antibody screen is negative is: the patient has an antibody against a high-incidence antigen the incompatible donor unit has a positive direct antiglobulin test cold agglutinins are interfering in the crossmatch the patient's serum contains warm autoantibody
the incompatible donor unit has a positive direct antiglobulin test
98
A blood specimen types as A, Rh-positive with a negative antibody screen. 6 units of group A, Rh-positive Red Blood Cells were crossmatched and 1 unit was incompatible in the antiglobulin phase. The same result was obtained when the test was repeated. Which should be done first? a repeat the ABO grouping on the incompatible unit using a more sensitive technique b test a panel of red cells that possesses low-incidence antigens c perform a direct antiglobulin test on the donor unit d_ obtain a new specimen and repeat the crossmatch
c perform a direct antiglobulin test on the donor unit
99
During emergency situations when there is no time to determine ABO group and Rh type on a current sample for transfusion, the patient is known to be A, Rh-negative. The technologist should: refuse to release any blood until the patient’s sample has been typed release A Rh-negative Red Blood Cells release O Rh-negative Red Blood Cells release O Rh-positive Red Blood Cells
release O Rh-negative Red Blood Cells
100
A 29-year-old male is hemorrhaging severely. He is AB, Rh-negative. 6 units of blood are required STAT. Of the following types available in the blood bank, which would be most preferable for crossmatch? a AB, Rh-positive b A, Rh-negative c A, Rh-positive dO, Rh-negative
b A, Rh-negative