BLOOD BANKING

92問 • 1年前

問題一覧

What type of serological testing does the blood bank technologist perform when determining the blood group of a patient? A. Genotyping B. Phenotyping C. Both genotyping and phenotyping D. Polymerase chain reaction

B. Phenotyping

If anti-K reacts 3+ with a donor cell with a genotype KK and 2+ with a Kk cell, the antibody is demonstrating: A. Dosage B. Linkage disequilibrium C. Homozygosity D. Heterozygosity

A. Dosage

Carla expresses the blood group antigens Fya, Fyb, and Xga. James shows expressions of none of these antigens. What factor(s) may account for the absence of these antigens in James? A. Gender B. Race C. Gender and race D. Medication

C. Gender and race

Which of the following describes the expression of most blood group antigens? A. Dominant B. Recessive C. Codominant D. Corecessive

C. Codominant

Which of the following enhancement mediums decreases the zeta potential, allowing antibody and antigen to come closer together? A. LISS B. Polyethylene glycol C. Polybrene D. ZZAP

A. LISS

Which antibodies to a component of complement are contained in the rabbit polyspecific antihuman globulin reagent for detection of in vivo sensitization? A. Anti-IgG and anti-C3a B. Anti-IgG and anti-C3d C. Anti-IgG and anti-IgM D. All of these options

B. Anti-IgG and anti-C3d

Which of the following distinguishes A1 from A2 blood groups? A. A2 antigen will not react with anti-A, A1 will react strongly (4+) B. An A2 person may form anti-A1; an A1 person will not form anti-A1 C. An A1 person may form anti-A2, an A2 person will not form anti-A1 D. A2 antigen will not react with anti-A from a nonimmunized donor; A1 will react with any anti-A

B. An A2 person may form anti-A1; an A1 person will not form anti-A1

A patient’s serum is incompatible with O cells. The patient RBCs give a negative reaction to anti-H lectin. What is the most likely cause of these results? A. The patient may be a subgroup of A B. The patient may have an immunodeficiency C. The patient may be a Bombay D. The patient may have developed alloantibodies

C. The patient may be a Bombay

Acquired B antigens have been found in: A. Bombay individuals B. Group O persons C. All blood groups D. Group A persons

D. Group A persons

What antibodies are formed by a Bombay individual? A. Anti-A and anti-B B. Anti-H C. Anti-A,B D. Anti-A, B, and H

D. Anti-A, B, and H

Blood is crossmatched on an A positive person with a negative antibody screen. The patient received a transfusion of A positive RBCs 3 years ago. The donors chosen for crossmatch were A positive. The crossmatch was run on the Ortho Provue and yielded 3+ incompatibility. How can these results be explained? A. The patient has an antibody to a low-frequency antigen B. The patient has an antibody to a high-frequency antigen C. The patient is an A2 with anti-A1 D. The patient is an A1 with anti-A2

C. The patient is an A2 with anti-A1

A patient’s red cells forward as group O, serum agglutinates B cells (4+) only. Your next step would be: A. Extend reverse typing for 15 minutes B. Perform an antibody screen including a room temperature incubation C. Incubate washed red cells with anti-A1 and antiA,B for 30 minutes at room temperature D. Test patient’s red cells with Dolichos biflorus

C. Incubate washed red cells with anti-A1 and antiA,B for 30 minutes at room temperature

Which typing results are most likely to occur when a patient has an acquired B antigen? A. Anti-A 4+, anti-B-3+, A1 cells neg, B cells neg B. Anti-A 3+, anti-B neg, A1 cells neg, B cells neg C. Anti-A 4+, anti-B 1+, A1 cells neg, B cells 4+ D. Anti-A 4+, anti-B 4+, A1 cells 2+, B cells neg

C. Anti-A 4+, anti-B 1+, A1 cells neg, B cells 4+

What type RBCs can be transfused to an A2 person with anti-A1? A. A only B. A or O C. B D. AB

B. A or O

What should be done if all forward and reverse ABO results as well as the autocontrol are positive? A. Wash the cells with warm saline, autoadsorb the serum at 4°C B. Retype the sample using a different lot number of reagents C. Use polyclonal typing reagents D. Report the sample as group AB

A. Wash the cells with warm saline, autoadsorb the serum at 4°C

What should be done if all forward and reverse ABO results are negative? A. Perform additional testing such as typing with antiA1 lectin and anti-A,B B. Incubate at 22°C or 4°C to enhance weak expression C. Repeat the test with new reagents D. Run an antibody identification panel

B. Incubate at 22°C or 4°C to enhance weak expression

N-acetyl-D-galactosamine is the immunodominant carbohydrate that reacts with: A. Arachis hypogaea B. Salvia sclarea C. Dolichos biflorus D. Ulex europeaus

C. Dolichos biflorus

A stem cell transplant patient was retyped when she was transferred from another hospital. What is the most likely cause of the following results? A. Viral infection B. Alloantibodies C. Immunodeficiency D. Autoimmune hemolytic anemia

C. Immunodeficiency

What reaction would be the same for an A1 and an A2 person? A. Positive reaction with anti-A1 lectin B. Positive reaction with A1 cells C. Equal reaction with anti-H D. Positive reaction with anti-A,B

D. Positive reaction with anti-A,B

A female patient at 28 weeks’ gestation yields the following results: Which of the following could be causing the ABO discrepancy? A. Hypogammaglobulinemia B. Alloantibody in patient serum C. Acquired B D. Weak subgroup

B. Alloantibody in patient serum

Which condition would most likely be responsible for the following typing results? A. Immunodeficiency B. Masking of antigens by the presence of massive amounts of antibody C. Weak or excessive antigen(s) D. Impossible to determine

C. Weak or excessive antigen(s)

Which of the following results is most likely discrepant? A. Negative B cells B. Positive reaction with anti-B C. Negative A1 cells D. No problem with this typing

C. Negative A1 cells

A 61-year-old male with a history of multiple myeloma had a stem cell transplant 3 years ago. The donor was O positive and the recipient was B positive. He is admitted to a community hospital for fatigue and nausea. Typing results reveal the following: Anti-A = 0 Anti-B =0 Anti-A,B = 0 Anti-D = 4+ A1 cells = 4+ B cells = 0 How would you report this type? A. O positive B. B positive C. A positive D. Undetermined

D. Undetermined

A complete Rh typing for antigens C, c, D, E, and e revealed negative results for C, D, and E. How is the individual designated? A. Rh positive B. Rh negative C. Positive for c and e D. Impossible to determine

B. Rh negative

How is an individual with genotype Dce/dce classified? A. Rh positive B. Rh negative C. Rhnull D. Total Rh

A. Rh positive

Which genotype usually shows the strongest reaction with anti-D? A. DCE/DCE B. Dce/dCe C. D–/D– D. -CE/-ce

C. D–/D–

Which donor unit is selected for a recipient with anti-c? A. r´r B. R0R1 C. R2r´ D. r´ry

D. r´ry

Why is testing for Rh antigens and antibodies different from ABO testing? A. ABO reactions are primarily due to IgM antibodies and usually occur at room temperature; Rh antibodies are IgG and agglutination usually requires a 37°C incubation and enhancement media B. ABO antigens are attached to receptors on the outside of the red cell and do not require an special enhancement for testing; Rh antigens are loosely attached to the red cell membrane and require enhancement for detection

A. ABO reactions are primarily due to IgM antibodies and usually occur at room temperature; Rh antibodies are IgG and agglutination usually requires a 37°C incubation and enhancement media

What is one possible genotype for a patient who develops anti-C antibody? A. R1r B. R1R1 C. r´r D. rr

D. rr

A patient developed a combination of Rh antibodies: anti-C, anti-E, and anti-D. Can compatible blood be found for this patient? A. It is almost impossible to find blood lacking the C, E, and D antigens B. rr blood could be used without causing a problem C. R0R0 may be used because it lacks all three antigens D. Although rare, ryr blood may be obtained from close relatives of the patient

B. rr blood could be used without causing a problem

Testing reveals a weak D that reacts 1+ after indirect antiglobulin testing (IAT). How is this result classified? A. Rh-positive B. Rh-negative, Du positive C. Rh-negative D. Rh-positive, Du positive

A. Rh-positive

A patient tests positive for weak D but also appears to have anti-D in his serum. What may be the problem? A. Mixup of samples or testing error B. Most weak D individuals make anti-D C. The problem could be due to a disease state D. A D mosaic may make antibodies to missing antigen parts

D. A D mosaic may make antibodies to missing antigen parts

Which offspring is not possible from a mother who is R1R2 and a father who is R1r? A. DcE/DcE B. Dce/DCe C. DcE/DCe

A. DcE/DcE

Why is testing a pregnant woman for weak D not required? A. An Rh-negative fetus may yield false positive results in a fetal maternal bleed B. An Rh-positive fetus may yield false positive results in a fetal maternal bleed C. D antigen strength decreases during pregnancy D. D antigen strength increases during pregnancy

B. An Rh-positive fetus may yield false positive results in a fetal maternal bleed

What techniques are necessary for weak D testing? A. Saline + 22°C incubation B. Albumin or LISS + 37°C incubation C. Saline + 37°C incubation D. 37°C incubation + IAT

D. 37°C incubation + IAT

What antibodies could an R1R1 make if exposed to R2R2 blood? A. Anti-e and anti-C B. Anti-E and anti-c C. Anti-E and anti-C D. Anti-e and anti-c

B. Anti-E and anti-c

A patient types as AB and appears to be Rh positive on slide typing. What additional tests should be performed for tube typing? A. Rh negative control B. Direct antiglobulin test (DAT) C. Low-protein Rh antisera D. No additional testing is needed

A. Rh negative control

. A physician orders 2 units of leukocyte-reduced red blood cells. The patient is a 55-year-old male with anemia. He types as an AB negative, and his antibody screen is negative. There is only 1 unit of AB negative in inventory. What is the next blood type that should be given? A. AB positive (patient is male) B. A negative C. B negative D. O negative

B. A negative

Which technology may report an Rh-weak D positive as Rh negative? A. Gel System B. Solid Phase C. Tube Testing D. None of these options

A. Gel System

A technologist is having great difficulty resolving an antibody mixture. One of the antibodies is anti- Lea . This antibody is not clinically significant in this situation, but it needs to be removed to reveal the possible presence of an underlying antibody of clinical significance. What can be done? A. Perform an enzyme panel B. Neutralize the serum with saliva C. Neutralize the serum with hydatid cyst fluid D. Use DTT (dithiothreitol) to treat the panel cells

B. Neutralize the serum with saliva

A patient has the Lewis phenotype Le(a−b−). An antibody panel reveals the presence of anti-Lea. Another patient with the phenotype Le(a−b+) has a positive antibody screen; however, a panel reveals no conclusive antibody. Should anti-Lea be considered as a possibility for the patient with the Le(a−b+) phenotype? A. Anti-Lea should be considered as a possible antibody B. Anti-Lea may be a possible antibody, but further studies are needed C. Anti-Lea is not a likely antibody because even Leb individuals secrete some Lea D. Anti-Lea may be found in saliva but not detectable in serum

C. Anti-Lea is not a likely antibody because even Leb individuals secrete some Lea

What type of blood should be given to an individual who has an anti-Leb that reacts 1+ at the IAT phase? A. Blood that is negative for the Leb antigen B. Blood that is negative for both the Lea and Leb antigens C. Blood that is positive for the Leb antigen D. Lewis antibodies are not clinically significant, so any type of blood may be given

A. Blood that is negative for the Leb antigen

Which of the following statements is true concerning the MN genotype? A. Antigens are destroyed using bleach-treated cells B. Dosage effect may be seen for both M and N antigens C. Both M and N antigens are impossible to detect because of cross-interference D. MN is a rare phenotype seldom found in routine antigen typing

B. Dosage effect may be seen for both M and N antigens

Anti-M is sometimes found with reactivity detected at the immediate spin (IS) phase that persists in strength to the IAT phase. What is the main testing problem with a strong anti-M? A. Anti-M may not allow detection of a clinically significant antibody B. Compatible blood may not be found for the patient with a strongly reacting anti-M C. The anti-M cannot be removed from the serum D. The anti-M may react with the patient’s own cells, causing a positive autocontrol

A. Anti-M may not allow detection of a clinically significant antibody

How can interfering anti-P1 antibody be removed from a mixture of antibodies? A. Neutralization with saliva B. Agglutination with human milk C. Combination with urine D. Neutralization with hydatid cyst fluid

D. Neutralization with hydatid cyst fluid

A patient is suspected of having paroxysmal cold hemoglobinuria (PCH). Which pattern of reactivity is characteristic of the Donath– Landsteiner antibody, which causes this condition? A. The antibody attaches to RBCs at 4°C and causes hemolysis at 37°C B. The antibody attaches to RBCs at 37°C and causes agglutination at the IAT phase

A. The antibody attaches to RBCs at 4°C and causes hemolysis at 37°C

Which antibody is frequently seen in patients with warm autoimmune hemolytic anemia? A. Anti-Jka B. Anti-e C. Anti-K D. Anti-Fyb

B. Anti-e

An antibody shows strong reactions in all test phases. All screen and panel cells are positive. The serum is then tested with a cord cell and the reaction is negative. What antibody is suspected? A. Anti-I B. Anti-i C. Anti-H D. Anti-p

A. Anti-I

Which group of antibodies is commonly found as cold agglutinins? A. Anti-K, anti-k, anti-Jsb B. Anti-D, anti-e, anti-C C. Anti-M, anti-N D. Anti-Fya, anti-Fyb

C. Anti-M, anti-N

What does the 3+3 rule ascertain? A. An antibody is ruled in B. An antibody is ruled out C. 95% confidence that the correct antibody has been identified D. 95% confidence that the correct antibody has not been identified

C. 95% confidence that the correct antibody has been identified

Which procedure would help to distinguish between an anti-e and anti-Fya in an antibody mixture? A. Lower the pH of test serum B. Run an enzyme panel C. Use a thiol reagent D. Run a LISS panel

B. Run an enzyme panel

Which characteristics are true of all three of the following antibodies: anti-Fya, anti-Jka, and antiK? A. Detected at the IAT phase; may cause hemolytic disease of the newborn and hemolytic transfusion reactions B. Not detected with enzyme-treated cells C. Requires the IAT technique for detection; usually not associated with HDN D. Enhanced reactivity with enzyme-treated cells; may cause severe hemolytic transfusion reactions

A. Detected at the IAT phase; may cause hemolytic disease of the newborn and hemolytic transfusion reactions

A patient is admitted to the hospital. Medical records indicate that the patient has a history of antiJka. When you performed the type and screen, the type was O positive and screen was negative. You should: A. Crossmatch using units negative for Jka antigen B. Crossmatch random units, since the antibody is not demonstrating C. Request a new sample D. Repeat the screen with enzyme-treated screening cells

A. Crossmatch using units negative for Jka antigen

A technologist performs an antibody study and finds 1+ and weak positive reactions for several of the panel cells. The reactions do not fit a pattern. Several selected panels and a patient phenotype do not reveal any additional information. The serum is diluted and retested, but the same reactions persist. What type of antibody may be causing these results? A. Antibody to a high-frequency antigen B. Antibody to a low-frequency antigen C. High titer low avidity (HTLA) D. Anti-HLA

C. High titer low avidity (HTLA)

An antibody is detected in a pregnant woman and is suspected of being the cause of fetal distress. The antibody reacts at the IAT phase but does not react with DTT-treated cells. This antibody causes in vitro hemolysis. What is the most likely antibody specificity? A. Anti-Lea B. Anti-Lua C. Anti-Lub D. Anti-Xga

C. Anti-Lub

What sample is best for detecting complement dependent antibodies? A. Plasma stored at 4°C for no longer than 24 hours B. Serum stored at 4°C for no longer than 48 hours C. Either serum or plasma stored at 20°C–24°C no longer than 6 hours D. Serum heated at 56°C for 30 minutes

B. Serum stored at 4°C for no longer than 48 hours

Which antibody would not be detected by group O screening cells? A. Anti-N B. Anti-A1 C. Anti-Dia D. Anti-k

B. Anti-A1

How would autoantibodies affect compatibility testing? A. No effect B. The DAT would be positive C. ABO, Rh, antibody screen, and crossmatch may show abnormal results D. Results would depend on the specificity of autoantibody

C. ABO, Rh, antibody screen, and crossmatch may show abnormal results

An antibody screen is reactive at IAT phase of testing using a three-cell screen and the autocontrol is negative. What is a possible explanation for these results? A. A cold alloantibody B. High-frequency alloantibody or a mixture of alloantibodies C. A warm autoantibody D. A cold and warm alloantibody

B. High-frequency alloantibody or a mixture of alloantibodies

Can crossmatching be performed on October 14th using a patient sample drawn on October 12th? A. Yes, a new sample would not be needed B. Yes, but only if the previous sample has no alloantibodies C. No, a new sample is needed because the 2-day limit has expired D. No, a new sample is needed for each testing

A. Yes, a new sample would not be needed

A type and screen was performed on a 32-yearold woman, and the patient was typed as AB negative. There are no AB-negative units in the blood bank. What should be done? A. Order AB-negative units from a blood supplier B. Check inventory of A-, B-, and O-negative units C. Ask the patient to make a preoperative autologous

B. Check inventory of A-, B-, and O-negative units

What type(s) of red cells is (are) acceptable to transfuse to an O-negative patient? A. A negative, B negative, AB negative, or O negative B. O negative C. AB negative D. AB negative, A negative, B negative

B. O negative

A technologist removed 4 units of blood from the blood bank refrigerator and placed them on the counter. A clerk was waiting to take the units for transfusion. As she checked the paperwork, she noticed that one of the units was leaking onto the counter. What should she do? A. Issue the unit if the red cells appear normal B. Reseal the unit C. Discard the unit D. Call the medical director and ask for an opinion

C. Discard the unit

A donor was found to contain anti-K using pilot tubes from the collection procedure. How would this affect the compatibility test? A. The AHG major crossmatch would be positive B. The IS (immediate spin) major crossmatch would be positive C. The recipient’s antibody screen would be positive for anti-K D. Compatibility testing would not be affected

D. Compatibility testing would not be affected

A patient showed positive results with screening cells and 4 donor units. The patient autocontrol was negative. What is the most likely antibody? A. Anti-H B. Anti-S C. Anti-Kpa D. Anti-k

D. Anti-k

Screening cells and major crossmatch are positive on IS only, and the autocontrol is negative. Identify the problem. A. Cold alloantibody B. Cold autoantibody C. Abnormal protein D. Antibody mixture

A. Cold alloantibody

Six units are crossmatched. Five units are compatible, one unit is incompatible, and the recipient’s antibody screen is negative. Identify the problem: A. Patient may have an alloantibody to a high-frequency antigen B. Patient may have an abnormal protein C. Donor unit may have a positive DAT D. Donor may have a high-frequency antigen

C. Donor unit may have a positive DAT

An incompatible donor unit is found to have a positive DAT. What should be done with the donor unit? A. Discard the unit B. Antigen type the unit for high-frequency antigens C. Wash the donor cells and use the washed cells for testing D. Perform a panel on the incompatible unit

A. Discard the unit

Screening cells, major crossmatch, and patient autocontrol are positive in all phases. Identify the problem. A. Specific cold alloantibody B. Specific cold autoantibody C. Abnormal protein or nonspecific autoantibody D. Cold and warm alloantibody mixture

C. Abnormal protein or nonspecific autoantibody

A panel study has revealed the presence of patient alloantibodies. What is the first step in a major crossmatch? A. Perform a DAT on patient cells and donor units B. Antigen type patient cells and any donor cells to be crossmatched C. Adsorb any antibodies from the patient serum D. Obtain a different enhancement medium for testing

B. Antigen type patient cells and any donor cells to be crossmatched

What is the disposition of a donor red blood cell unit that contains an antibody? A. The unit must be discarded B. Only the plasma may be used to make components C. The antibody must be adsorbed from the unit D. The unit may be labeled indicating it contains antibody and released into inventory

D. The unit may be labeled indicating it contains antibody and released into inventory

Given a situation where screening cells, major crossmatch, autocontrol, and DAT (anti-IgG) are all positive, what procedure should be performed next? A. Adsorption using rabbit stroma B. Antigen typing of patient cells C. Elution followed by a cell panel on the eluate D. Selected cell panel

C. Elution followed by a cell panel on the eluate

How long must a recipient sample be kept in the blood bank following compatibility testing? A. 3 days B. 5 days C. 7 days D. 10 days

C. 7 days

What is the crossmatching protocol for platelets and/or plasma? A. Perform a reverse grouping on donor plasma B. No testing is required C. Perform a reverse grouping on recipient plasma D. Platelets must be HLA compatible

B. No testing is required

What are the compatibility requirements for an autologous unit? A. ABO and Rh typing B. Type and screen C. Major crossmatch D. All of these options

A. ABO and Rh typing

A patient types as AB positive. Two units of blood have been ordered by the physician. Currently, the inventory shows no AB units, 10 A-positive units, 1 Anegative unit, 5 B-positive units, and 20 O-positive units. Which should be set up for the major crossmatch? A. A-positive units B. O-positive units C. B-positive units D. Call another blood supplier for type-specific Blood

A. A-positive units

Which of the following comprises an abbreviated crossmatch? A. ABO, Rh, and antibody screen B. ABO, Rh, antibody screen, IS crossmatch C. Type and screen D. ABO, Rh, IS crossmatch

B. ABO, Rh, antibody screen, IS crossmatch

A patient had a transfusion reaction to packed red blood cells. The medical laboratory scientist began the laboratory investigation of the transfusion reaction by assembling pre- and post-transfusion specimens and all paperwork and computer printouts. What should he do next? A. Perform a DAT on the post-transfusion sample B. Check for a clerical error(s) C. Repeat ABO and Rh typing of patient and donor unit D. Perform an antibody screen on the posttransfusion sample

B. Check for a clerical error(s)

What is the pathophysiological cause surrounding anaphylactic and anaphylactoid reactions? A. Antibody in patient serum is detected 3–7 days after transfusion, and is attached to donor red blood cells B. Donor plasma has reagins (IgE or IgA) that combine with allergens in patient plasma C. Patient is deficient in IgE and develops IgE antibodies via sensitization from transfusion or pregnancy D. Patient is deficient in IgA and develops IgA antibodies via sensitization from transfusion or pregnancy

D. Patient is deficient in IgA and develops IgA antibodies via sensitization from transfusion or pregnancy

A patient has a hemolytic reaction to blood transfused 8 days ago. What is the most likely cause? A. Immediate, nonimmunologic probably due to volume overload B. Delayed immunologic, probably due to an antibody such as anti-Jka C. Delayed nonimmunologic, probably due to iron overload D. Immediate, immunologic, probably due to clerical error, ABO incompatibility

B. Delayed immunologic, probably due to an antibody such as anti-Jka

What may be found in the serum of a person who is exhibiting signs of TRALI (transfusion-related acute lung injury)? A. Red blood cell alloantibody B. IgA antibody C. Anti-leukocy

C. Anti-leukocyte antibody

Which type of transfusion reaction occurs in about 1% of all transfusions, results in a temperature rise of 1°C or higher, is associated with blood component transfusion, and is not related to the patient’s medical condition? A. Immediate hemolytic B. Delayed hemolytic C. Febrile nonhemolytic reaction D. Transfusion-related acute lung injury

C. Febrile nonhemolytic reaction

What would be the result of group A blood given to an O patient? A. Nonimmune transfusion reaction B. Immediate hemolytic transfusion reaction C. Delayed hemolytic transfusion reaction D. Febrile nonhemolytic transfusion reaction

B. Immediate hemolytic transfusion reaction

All of the following are part of the preliminary evaluation of a transfusion reaction, except: A. Check pre- and post-transfusion samples for color of serum B. Perform ABO and Rh recheck C. DAT on the post-transfusion sample D. Panel on pre- and post-transfusion samples

D. Panel on pre- and post-transfusion samples

A 68-year-old female diagnosed with neutropenia and inflammation of the left hand was typed as A positive, and received 1 packed red blood cell unit. The antibody screen was negative and crossmatch was compatible. During the transfusion, her pulse was 94, and blood pressure rose from 114/59 to 132/64. Her temperature rose from 37.1°C pretransfusion to 37.8°C 60 minutes after starting transfusion, then to 38.1°C upon completion. A post transfusion specimen yielded plasma that was neither hemolyzed nor icteric, and a negative DAT. Post transfusion urinalysis gave a 1+ blood and protein with 10 RBCs/hpf microscopically. The clerical check was acceptable. What type of reaction most likely occurred as a result of transfusion? A. Allergic B. Circulatory overload C. Febrile nonhemolytic D. Delayed hemolytic

C. Febrile nonhemolytic

Patient DB received 2 units of group A-positive red cells 2 days ago. Two days later, he developed a fever and appeared jaundiced. His blood type was A positive. A transfusion reaction workup was ordered. There were no clerical errors detected. A posttransfusion specimen was collected and a DAT performed. The DAT was positive with monospecific anti-IgG. The plasma was also hemolyzed. An antibody screen and panel studies revealed the presence of anti-Jkb (postspecimen). The antibody screen on the pretransfusion specimen was negative. Which of the following explain the positive DAT? A. The donor cells had a positive DAT B. The donor cells were polyagglutinable C. The donor cells were likely positive for the Jkb antigen D. The recipient cells were likely positive for the Jkb antigen

C. The donor cells were likely positive for the Jkb antigen

A 92-year-old male diagnosed with anemia and episodes of frequent falling was typed as B negative and transfused 1 unit of packed red blood cells, also B negative. He was not recently transfused, and the antibody screen was negative. During the transfusion, his temperature rose from 36.2°C to 36.4°C, his pulse rose from 96 to 124, respirations from 18 to 20, and BP from 127/81 to 174/83. He was transfused with 205 mL before a reaction was called by the transfusionist. The postspecimen DAT was negative and clerical check acceptable. Urinalysis yielded 1+ blood with 5 RBCs microscopically. Other symptoms included tachycardia and flushing. What reaction had most likely taken place? A. Febrile nonhemolytic B. Acute hemolytic C. Anaphylactic D. Volume overload

D. Volume overload

A 76-year-old female diagnosed with urosepsis was transfused 2 units of packed red blood cells. Her type was AB positive with a negative antibody screen. The units transfused were AB positive. Upon receiving the second unit, the patient became hypoxic with tachypnea. The clerical check was acceptable and DAT negative. She received 269 mL from the second unit before a reaction was called. Her temperature fell from 38°C to 36.4°C, her pulse increased from 72 to 90, and respirations rose from 35 to 41. Her BP was 110/70. The patient expired approximately 12 hours from the time the reaction was called. What type of reaction was most likely present? A. Febrile B. Symptoms not related to transfusion C. Allergic D. TRALI

B. Symptoms not related to transfusion

A 52-year-old male received 2 units of packed red blood cells as an outpatient in the IV therapy unit. He had a 20-year history of head trauma and was quadriplegic. He had recurrent pneumonia and hematuria due to removal of a Foley catheter. His blood type was A positive with a previously identified anti-Fya. There was an ABO discrepancy in that the A1 cells were positive. The technologist attributed the reaction to the Fya antigen being present on the A1 cells. The patient also had a cold autoantibody. Two units of A-positive packed cells were crossmatched that were Fya negative, and were compatible. One unit was transfused at 11:30 a.m. without incident. The second unit was transfused at 2:16 p.m., and stopped at 3:55 p.m. due to reddish brown–tinged urine discovered in his collection bag. A posttransfusion specimen yielded a positive DAT, and plasma that was grossly hemolyzed. A prewarm crossmatch was incompatible in both the pre- and postspecimen. Anti-E and c were present in the postspecimen. What reaction was most likely present? A. Acute hemolytic B. Febrile C. Allergic D. TRALI

A. Acute hemolytic

An 82-year-old male was admitted for renal failure. His type was B positive, and his antibody screen was negative. Two units of red cells were ordered. The first unit was transfused at 1:00 p.m. without incident. The second was started at 4:15 p.m. and stopped at 5:12 p.m., after the nurse observed the patient had expired. Vital signs were taken at 4:30 p.m. with no abnormalities. A transfusion reaction was called and the blood unit, tubing, and paperwork sent to the blood bank. There were no clinical manifestations noted on the paperwork and no posttransfusion specimen was sent to the blood bank. What type of reaction most likely occurred? A. Symptoms not related to transfusion B. Acute hemolytic reaction C. Anaphylactic reaction D. Volume overload

A. Symptoms not related to transfusion

IMPORTANT: 1. The positive and negative control values for an ELISA procedure are below their acceptable ranges. What is the most likely cause? a. Decay of the positive and negative controls b. Incomplete washing following specimen addition c. Overly long incubation times d. Decay of the antibody-enzyme conjugate

d. Decay of the antibody-enzyme conjugate

IMPORTANT: What outcome results from improper washing of a tube or well after adding the enzyme-antibody conjugate in an ELISA system? a. Result will falsely decreased b. Results will be falsely increased c. Result will be unaffected d. Result is impossible to determine

b. Results will be falsely increased

other names parasitology

Yves Laure Pimentel · 70問 · 2年前

other names parasitology