Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

SBB ASCP > BOC BB QUESTIONS > Flashcards

BOC BB QUESTIONS Flashcards

1
Q

The minimum hemoglobin concentration in a fingerstick from a male blood donor is:

  1. 0 g/dL (120 g/L)
  2. 5 g/dL (125 g/L)
  3. 5 g/dL (135 g/L)
  4. 0 g/dL (150 g/L)
A

All donors, regardless of sex, requrire a minimum hemoglobin of 12.5 g/dL (125 g/L). The value must not be performed on an earlobe stick.

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

A cause for permanent deferral of blood donation is:

  • Diabetes
  • Residence in an endemic malarial region
  • History of jaundice of uncertain cause
  • History of therapeutic rabies vaccine
A

Jaundice is a sign of liver impairment, which might be due to HBV or HCV. Infection with HBV and HCV is a cause for indefinite deferral.

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

Which of the following prospective donors would be accepted for donation?

32-year-old woman who received a transfusion in a complicated delivery 5 months previously

19-year-old sailor who has been stateside for 9 months and stopped taking his anti-malarial medication 9 months previously

22-year-old college student who has a temperature of 99.2F (37.3C) and states that he feels well, but is nervous about donating

45-year-old woman who has just recovered from a bladder infection and is still taking antibiotics

A

The receipt of blood products is a 6 month deferral, the deferral for travel to areas endemic for malaria is 12 months regardless of antimalarial prophylaxis, and a person taking antibiotics may have bacteremia. The requirement for temperature is not over 37.5C or 99.5F.

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

Which one of the following constitutes permanent rejection status of a donor?

A tattoo 5 months previously

Recent close contact with a patient with viral hepatitis

2 units of blood transfused 4 months previously

Confirmed positive test for HBsAg 10 years previously

A

A positive test for HbsAg at anytime is an indefinite deferral.

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

According to AABB standards, which of the following donors may be accepted as a blood donor?

Traveled to an area endemic for malaria 9 months previously

Spontaneous abortion at 2 months of pregancy, 3 months previously

Resides with a known hepatitis patient

Received a blood transfusion 22 weeks previously

A

A woman who had a spontaneous abortion at 2 months of pregancy, 3 months previously would be acceptable. A donor is acceptable if she has not been pregnant in the previous 6 weeks.

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

Below are the results of the history obtained from a prospective female blood donor:

Age: 16

Temperature: 99.0F (37.2C)

Hct: 36%

History: Tetanus toxoid 1 week previously

How many of the above results excludes this donor from giving a routine blood transfusion?

a. None
b. 1
c. 2
d. 3

A

The Hct must be >38%. A donor may be 16 unless state law differs. Temperature must not exceed 99.5F/37.5C, blood pressure must be be <180mm Hg systolic <100 mm Hg diastolic, pulse 50-100 unless an athlete (which can be lower). Toxoids and vaccines from synthetic or killed sources have no deferral.

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

For apheresis donors who donate platelets more frequently than every 4 weeks, a platelet count must be performed prior to the procedure and be at least:

150 x 103/μL (150 x 109/L)

200 x 103/μL (200 x 109/L)

250 x 103/μL (250 x 109/L)

300 x 103/μL (300 x 109/L)

A

The minimum platelet count required for frequent repeat donors is 150x103/μL (150 x 109/L). A platelet count is not required prior to the first donation of if the interval between donations is at least 4 weeks.

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

Prior to blood donation, the intended venipuncture site must be cleaned with a scrub solution containing:

Hypochlorite

Isopropyl alcohol

10% acetone

PVP iodine complex

A

The scrub must use iodine, eg, PVP iodine complex. Donors who are sensitive to iodine can have the area cleaned with a preparation of 2% chlorhexidine and 70% isopropyl alcohol.

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

All donor blood testing must include:

Complete Rh phenotyping

anti-CMV testing

Direct antiglobulin test

Serological test for syphilis

A

Testing for syphilis was the first mandated donor screening test for infectious disease and is still part of donor screening.

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

During the preparation of Platelet Concentrates from Whole Blood, the blood should be:

Cooled towards 6C

Cooled towards 20-24C

Warmed to 37C

Heated to 57C

A

Platelets are prepared and stored at 20-24C for optimum function.

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

The most common cause of posttransfusion hepatitis can be detected in donors by testing for:

anti-HCV

HBsAg

anti-HAV IgM

anti-HBe

A

The most common posttransfusion hepatitis is hepatitis B. The estimated risk of transmission is 1:220,000 units transfused. The risk of hepatitis C transmission is 1:1,800,000 units. Hepatitis B surface antigen (HBsAg) is a required donor test for detection of acute or chronic HBV infection.

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

The Western blot is a confirmatory test for the presence of:

CMV antibody

Anti-HIV-1

HBsAg

Serum protein abnormalities

A

Western blot uses purified HIV proteins to confirm reactivity in samples whose screening test for anti-HIV is positive.

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

The test that is currently used to detect donors who are infected with the AIDS virus is:

anti-HBc

anti-HIV 1,2

HBsAg

ALT

A

The causative agent for AIDs is the human immunodeficiency virus types 1 and 2.

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

A commonly used screening method for anti-HIV-1 detection is:

Latex agglutination

Radioimmunoassay (RIA)

Thin-layer-chromatography (TLC)

enzyme -labeled immunosorbent assay (ELISA)

A

The enzyme-labeled immunosorbent assay (ELISA) method is a very sensitive method employed to screen donors for markers of transfusion-transmitted viruses.

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

Rejuvenation of a unit of Red Blood Cells is a method used to:

  • Remove antibody attached to RBC’s
  • Inactive viruses and bacteria
  • Restore 2,3 DPG and ATP to normal levels
  • Filter blood clots and other debris
A

Rejuvenation of RBCs uses additives to restore or enhance 2,3-DPG and ATP levels.

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

unit of packed cells is split into 2 aliquots under closed sterile conditions at 8am. The expiration time for each aliquot is now:

  • 4pm on the same day
  • 8pm on the same day
  • 8am the next morning
  • The original date of the unsplit unit.
A

Sterile docking devices allow entry into donor units without affecting the expiration date of the product.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

A unit of Red Blood Cells expiring in 35 days is split into 5 small aliquots using a sterile pediatric quad set and a sterile connecting device. Each aliquot must be labeled as expiring in:

  • 6 hours
  • 12 hours
  • 5 days
  • 35 days
A

Sterile docking devices allow entry into donor units without affecting the expiration date of the product.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

When platelets are stored on a rotator set on a open bench top, the ambient air temperature must be recorded:

  • Once a day
  • Twice a day
  • Every 4 hours
  • Every hour
A

If storage devices do not have automated temperature recording, temperature must be manually monitored every 4 hours.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Which of the following in the correct storage temperature for the component listed?

  • Cryoprecipitated AHF, 4C
  • Fresh Frozen Plasma (FFP), -20C
  • Red Blood Cells, Frozen, -40C
  • Platelets, 37C
A

Fresh Frozen Plasma is stored at -18C or below for 12 months.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

A unit of Red Blood Cells is issued at 9:00am. At 9:10am the unit is returned to the Blood Bank. The container has not been entered, but the unit has not been refrigerated during this time span. The best course of action for the technologist is to:

  • Culture the unit for bacterial contamination
  • Discard the unit if not used within 24 hours
  • Store the unit at room temperature
  • Record the return and place the unit back into inventory
A

Blood may be returned to the blood bank after issue provided that 1) the container has not been entered, 2) at least 1 sealed segment is attached to the container, 3) visual inspection of the unit is satisfactory and documented, and 4) the unit has been maintained at the appropriate storage or transport temperature. Studies have shown that refrigerated components retain an acceptable temperature of <10C for up to 30 minutes after removal from the refrigerator.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

The optimum storage temperature for Red Blood Cells, Frozen is:

  • -80C
  • -20C
  • -12C
  • 4C
A

Red Blood Cells, Frozen with 40% glycerol are stored at -65C or lower.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

The optimum storage temperature for Red Blood Cells is:

  • -80C
  • -20C
  • -12C
  • 4C
A

Red Blood Cells are stored at 1-6C

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

If the seal is entered on a unit of Red Blood Cells stored at 1C to 6C, what is the maximum allowable storage period, in hours?

  • 6
  • 24
  • 48
  • 72
A

If the seal is broken during processing, components are considered to be prepared in an open system, rather than a closed system. The expiration time for Red Blood Cells in an open system is 24 hours.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

The optimum storage temperature for cryoprecipitated AHF is:

  • -20C
  • -12C
  • 4C
  • 22C
A

Cryoprecipitated AHF is stored at -18C or lower

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Cryoprecipitated AHF must be transfused within what period of time following thawing and pooling?

  • 4 hours
  • 8 hours
  • 12 hours
  • 24 hours
A

Cryoprecipitate must be transfused with 4 hours of pooling.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Platelets prepared in a polyolefin type container, stored at 22-24C in 50 mL of plasma, and gently agitated can be used for up to:

  • 24 hours
  • 48 hours
  • 3 days
  • 5 days
A

Whole blood-derived platelets are stored at 20-24C with continuous gentle agitation. Platelets prepared by the PRP method may be stored for up to 5 days.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

The optimum storage temperature for platelets is:

  • -20C
  • -12C
  • 4C
  • 22C
A

The required temperature for storage of platelets is 20-24C

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

According to AABB standards, Fresh Frozen Plasma must be infused within what period of time following thawing?

  • 24 hours
  • 36 hours
  • 48 hours
  • 72 hours
A

Per AABB standards, thawed FFP should be stored at 1-6C for no more than 24 hours

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

Cryoprecipitated AHF, if maintained in the frozen state at -18C or below, has a shelf life of:

  • 42 days
  • 6 months
  • 12 months
  • 36 months
A

Cryoprecipitate has a shelf life of 12 months in the frozen state

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

Once thawed, Fresh Frozen Plasma must be transfused within:

  • 4 hours
  • 8 hours
  • 12 hours
  • 24 hours
A

Once thawed, FFP is stored at 1-6C for up to 24 hours.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

An important determination of platelet viability following storage is:

  • Plasma potassium concentration
  • Plasma pH
  • Prothrombin time
  • Activated partial thromboplastin time
A

The pH of platelets should be maintained at 6.2 or above throughout the storage period

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

In the liquid state, plasma must be stored at:

  • 1-6C
  • 22C
  • 37C
  • 56C
A

The required temperature for storage of thawed plasma is 1-6C.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

During storage, the concentration of 2,3-DPG deceases in a unit of:

  • Platelets
  • Fresh Frozen Plasma
  • Red Blood Cells
  • Cryoprecipitated AHF
A

2,3 DPG declines during storage of Red Blood Cells, causing a “shift to the left” in the oxygen dissociation curve and an impaired ability to deliver oxygen to the tissues.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

Cryoprecipitated AHF:

  • Is indicated for fibrinogen deficiencies
  • Should be stored at 4C prior to administration
  • Will not transmit hepatitis B virus
  • Is indicated for the treatment of hemophilia B
A

Cryoprecipitate is used primarily for fibrinogen replacement. It is stored at room temperature (20-24C) after thawing and must be infused within 6 hours. If pooled with other cryo units, it must be infused within 4 hours.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

Which apheresis platelets product should be irradiated?

  • Autologous unit collected prior to surgery
  • Random stock unit going to a patient with DIC
  • A directed donation given by a mother for her son
  • A directed donation given by an unrelated family friend
A

Blood products from blood relatives containing viable lymphocytes must be irradiated to inhibit the proliferation of T cells and subsequent GVHD.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

Irradiation of a unit of Red Blood Cells is done to prevent the replication of donor:

  • Granulocytes
  • Lymphocytes
  • Red cells
  • Platelets
A

Irradiation inhibits proliferation of T lymphocytes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

Plastic bag overwraps are recommended when thawing units of FFP in 37C water baths because they prevent:

  • The FFP bag from cracking when it contacts the warm water
  • Water from slowly dialyzing across the bag membrane
  • The entry ports from becoming contaminated with water
  • The label from peeling off as the water circulates in the bath
A

FFP thawed in a water bath should be protected so that entry ports are not contaminated with water. One may use a plastic overwrap or keep ports above water level.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

Which of the following blood components must be prepared within 8 hours after phlebotomy?

  • Red Blood Cells
  • Fresh Frozen Plasma
  • Red Blood Cells, frozen
  • Cryoprecipitated AHF
A

Fresh Frozen Plasma (FFP) must be separated and frozen within 8 hours of Whole Blood collection.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

Cryoprecipitated AHF contains how many units of Factor VIII?

  • 40
  • 80
  • 130
  • 250
A

Cryoprecipitate contains at least 80 units of AHF

40
Q

Which of the following blood components contains the most Factor VIII concentration relative to volume?

  • Single donor plasma
  • Cryoprecipitated AHF
  • Fresh Frozen Plasma
  • Platelets
A

Cryoprecipitated AHF contains at least 80 IU of Factor VIII concentrated in about 10 mL of plasma.

41
Q

The most effective component to treat a patient with fibrinogen deficiency is:

  • Fresh Frozen Plasma
  • Platelets
  • Fresh Whole Blood
  • Cryoprecipitated AHF
A

Cryoprecipitate is indicated as a source of fibrinogen for hypofibrinogenemia. It contains a minimum of 150 mg of fibrinogen concentrated in a small volume of plasma.

42
Q

A blood component prepared by thawing Fresh Frozen Plasma at refrigerator temperature and removing the fluid portion is:

  • Plasma Protein Fraction
  • Cryoprecipitate AHF
  • Factor IX Complex
  • FP24
A

Cryoprecipitate is the fraction of plasma proteins that precipitate when FFP is slowly thawed at 1-6C

43
Q

Upon inspection, a unit of platelets is noted to have visible clots, but appears normal. The technologist should:

  • Issue without concern
  • Filter to remove the clots
  • Centrifuge to express off the clots
  • Quarantine for gram stain and culture
A

Clots in the unit may indicate contamination

44
Q

According to AABB standards, at least 90% of all apheresis platelets units tested shall contain a minimum of how many platelets?

  • 5.5 x 1010
  • 6.5 x 1010
  • 3.0 x 1011
  • 5.0 x 1011
A

Per AABB standards, at least 90% of platelet pheresis units sampled must contain at least 3.0 x 1011 platelets

45
Q

According to AABB standards, Platelets prepared from Whole Blood shall have at least:

  • 5.5 x1010 platelets per unit in at least 90% of the units tested
  • 6.5 x 1011 platelets per unit in 90% of the units tested
  • 7.5 x 1010 platelets per unit in 100% of the units tested
  • 8.5 x 1010 platelets per unit in 95% of units tested
A

Per AABB standards, at least 90% of the platelet units prepared from Whole Blood that are sampled must contain at least 5.5 x 1010 platelets.

46
Q

Which of the following is proper procedure for preparation of Platelets from Whole Blood?

  • Light spin followed by a hard spin
  • Light spin followed by 2 hard spins
  • 2 light spins
  • Hard spin followed by a light spin
A

Whole blood-derived Platelets are prepared by a light spin to separate the Red Blood Cells from the platelet-rich plasma (PRP), followed by a heavy spin of the PRP to concentrate the platelets

47
Q

According to AABB standards, what is the minimum pH required for platelets at the end of the storage period?

  • 6.0
  • 6.2
  • 6.8
  • 7.0
A

Per AABB standards, at least 90% of platelet units sampled must have a pH of at least 6.2 at the end of the allowable storage.

48
Q

According to AABB standards, Platelets must be:

  • Gently agitated if stored at room temperature
  • Separated within 12 hours of Whole Blood collection
  • Suspended in sufficient plasma to maintain a pH of 5.0 or lower
  • Prepared only from Whole Blood units that have been stored at 4C for 6 hours
A

Per AABB standards, store Platelets at 20-24C with continuous agitation. Platelets must be separated from Whole Blood units and maintained at a temperature of at least 20C. The pH must be at least 6.2 at the end of the storage time.

49
Q

A unit of whole blood-derived (random donor) Platelets should contain at least:

  • 1.0 x 1010 platelets
  • 5.0 x 1010 platelets
  • 5.5 x 1011 platelets
  • 90% of the platelets from the original unit of Whole Blood
A

Whole blood-derived (random donor) Platelets should contain at least 5.5 x 1010 platelets, be stored with continuous agitation at 20-24C, and have a pH of 6.2 or higher when tested at the end of the storage period.

50
Q

Platelets prepared by apheresis should contain at least:

  • 1.0 x 1010 platelets
  • 3.0 x 1010 platelets
  • 3.0 x 1011 platelets
  • 5.0 x 1011 platelets
A

Apheresis (single donor) Platelets should contain at least 3.0 x 1011 platelets, be stored with continuous agitation at 20-24C, and have a pH of 6.2 or higher when tested at the end of the storage period

51
Q

Leukocyte-reduced red blood cells are ordered for a newly diagnosed bone marrow candidate. What is the best way to prepare this product?

  • Crossmatch only CMV-seronegative units
  • Irradiate the unit with 1,500 rads
  • Wash the unit with saline prior to infusion
  • Transfuse through a Log3 leukocyte-removing filter
A

Newly diagnosed bone marrow candidates are at great risk for severe sequelae of CMV infections. Infections can best be reduced by using leukocyte-reduction filters. CMV-seronegative units are rarely used since leukocyte reducing via filtration is so effective. Washing does not remove as many leukocytes as filtering.

52
Q

Of the following blood components, which one should be used to prevent HLA alloimmunization of the recipient?

  • Red Blood Cells
  • Granulocytes
  • Irradiated Red Blood Cells
  • Leukocyte-Reduced Red Blood Cells
A

Leukoreduction of blood products reduces donor leukocytes to less than 5 x 106 and decreases the risk of HLA alloimmunization.

53
Q

A father donating Platelets for his son is connected to a continuous flow machine, which uses the principle of centrifugation to separate Platelets from Whole Blood. As the Platelets are harvested, all other remaining elements are returned to the donor. This method of Platelet collection is known as:

  • Apheresis
  • Autologous
  • Homologous
  • Fractionated
A

The apheresis process is to remove whole blood, the desired component removed, and the remaining portion of blood returned to the donor/patient.

54
Q

To qualify as a donor for autologous transfusion a patient’s hemoglobin should be at least:

  • 8 g/dL (80 g/L)
  • 11 g/dL (110 g/L)
  • 13 g/dL (130 g/L)
  • 15 g/dL (150 g/L)
A

Autologous donors have less stringent criteria than allogeneic donors. Donations must be collected at least 72 hours prior to surgery.

55
Q

What is/are the minimum pretransfusion requirements for autologous donations collected and transfused in the same facility?

  • ABO and Rh typing only
  • ABO/Rh type, antibody screen
  • ABO/Rh type, antibody screen, crossmatch
  • No pretransfusion testing is required for autologous donations
A

Only ABO and Rh is required with the patient’s sample. Each autologous unit must be confirmed for ABO and Rh from an integrally attached segment.

56
Q

In a quality assurance program, Cryoprecipitated AHF must contain a minimum of how many international units of Factor VIII?

  • 60
  • 70
  • 80
  • 90
A

FDA requirements that 4 representative units be tested each month for Factor VIII levels of 80 IU or higher. If the average value is less than 80 IU of Factor VIII, corrective action must be taken.

57
Q

An assay of plasma from a bag of cryoprecipitated AHF yields a concentration of 9 international units (IU) of factor VIII per mL of Cryoprecipitated AHF. If the volume is mL, what is the Factor VIII content of the bag in IU?

  • 9
  • 18
  • 27
  • 81
A

To determine the total IU of Factor VIII per bag of cryoprecipitate, multiple the assayed value/mL by the number of mL in the container. (81)

58
Q

Antigens

Panel Cells

1

2

3

4

5

Test results

I

+

0

0

+

+

+

II

0

0

+

0

+

0

III

0

+

+

+

0

0

IV

0

+

+

0

+

+

V

+

+

+

0

0

+

Auto

0

Given the most probable genotypes of the parents, which of the following statements best describes the most probable Rh genotypes of the 4 children?

  1. 2 are R1r, 2 are R1R1
  2. 3 are R1r, 1 is rr
  3. 1 is R0r, 1 is R1r, 2 are R1R1
  4. 1 is R0r, 1 is R1R1, 2 are R1r
A

The mother has a 50% chance of passing on R1 and 50% chance of passing on r. The father will always pass on R1. Statistically 50% of the children will be R1r and 50% of them will be R1R1.

59
Q

The linked HLA genes on each chromosome constitutes a(n):

  • Allele
  • Trait
  • Phenotype
  • Haplotype
A

The entire set of HLA antigens located on one chromosome is a haplotype

60
Q
  1. An individual’s red blood cells give the following with Rh antisera:

Anti-D

Anti-C

Anti-E

Anti-c

Anti-e

Rh control

4+

3+

0

3+

3+

0

The individual’s most probable genotype is:

  1. DCe/DcE
  2. DcE/dce
  3. Dce/dce
  4. DCe/dce
A

The patient lacks E. Since C and c are alleles, C is inherited from one parent and c from the other. Since the person is homozygous for e, one of the genes needs to code for ce (Rhce) and the other Ce (RhCe). The RHD gene is more likely inherited with Ce than ce, so the person’s most probable genotype is found in 31% of the white and 15% of the black populations.

61
Q

A blood donor has the genotype: hh, AB. What is his red blood cell phenotype?

  • A
  • B
  • O
  • AB
A

The A and B structures can not be developed since there is no H gene in the blood donor

62
Q

An individual has been a sensitized to the k antigen and has produced anti-k. What is her most probable Kell system genotype?

  • KK
  • Kk
  • Kk
  • K0K0
A

This individual cannot have the k antigen on their cells. K0K0 is rare and no Kell system antigens are detected on the red blood cells. Those individuals usually produce antibodies that are reactive with all normal cells. KK is the most probable genotype.

63
Q

Given the following typing results, what is this donor’s racial ethnicity? Le(a-b-); Fy(a-b-);Jsa(a+b+)

  • African American
  • Asian American
  • Native American
  • Caucasin
A

Fy(a-b-) individuals are very rare with all populations other than the individual of african descent. 68% of African Americans are Fy(a-b-)

64
Q

A mother has the red cell phenotype D+,C+,E-,c-,e+ with and anti-c (titer of 32 at AHG) in her serum. The father has the phenotype D+C+E-c+e+. The baby is Rh-negative and not affected with hemolytic disease of the newborn. What is the baby’s most probable Rh genotype?

  • r’r’
  • r’r
  • R1R2
  • R1r
A

The baby is Rh-negative and lacks c, since there is no evidence of HDFN. Inheritance of no D and no c is denoted as r’. The baby must have inherited this gene from both parents, and is homozygous.

65
Q

In an emergency situation, Rh-negative red cells are transfused into an Rh-positive person of the genotype CDe/CDe. The first antibody MOST likely to develop is:

  • Anti-c
  • Anti-d
  • Anti-e
  • Anti-E
A

The most common genotype in Rh-negative individuals is rr. Anti-e would not be formed because the recipient’s red cells contain the e antigen. The first antibody most likely to develop would be anti-c

66
Q

Most blood group systems are inherited as:

  • Sex-linked dominant
  • Sex-linked recessive
  • Autosomal recessive
  • Autosomal codominant
A

Most blood group systems are Autosomal codominant

67
Q

The mating of an Xg(a+) man and a Xg(a-) woman will only produce:

  • Xg(a-) sons and Xg(a-) daughters
  • Xg(a+) sons and Xg(a+) daughters
  • Xg(a-) sons and Xg(a+) daughters
  • Xg(a+) sons and Xg(a-) daughters
A

The Xg blood group system is unique in that the gene encodes on the X chromosome. A negative mother would not have the Xg(a) to pass on. A positive father would however, transmit the Xg(a) to all his daughters.

68
Q
  1. Refer to the following data:

Anti-C

Anti-D

Anti-E

Anti-c

Anti-e

+

+

+

+

+

Given the reactions above, which is the most probable genotype?

  1. R1R1
  2. R1r
  3. R0r’’
  4. R1R2
A

All common Rh antigens are present on the red blood cells. R1 (DCe) and R2 (DcE) are frequent genotypes.

69
Q
  1. A patient’s red cell type as follows:

Anti-D

Anti-C

Anti-E

4+

0

0

Which of the following genotype would be consistent with these results?

  1. R0R0
  2. R1r
  3. R1R2
  4. Rzr
A

R0R0 is the only correct choice here. R0 = D+C-E-c+e+.

70
Q

The red cells of a nonsecretor (se/se) will most likely type as:

  • Le(a-b-)
  • Le(a+b+)
  • Le(a+b-)
  • Le(a-b+)
A

The Lewis antigens are developed by gene interaction. Both the Lewis and Secretor gene are required for red cells to type as Le(a-b+). If a person has a Lewis gene, but not a Secretor gene, then the cells type as Le(a+b-). The Le(a-b-) phenotype is derived when the Lewis gene is absent and the Secreter gene may or may not be present. The Le(a+b-) phenotype occurs in 22% or the population, and Le(a-b-)occurs in 6%, so the most likely phenotype of a nonsecretor (se/se) is Le(a+b-).

71
Q

Which of the following Phenotypes will react with anti-f?

  • rr
  • R1R1
  • R2R2
  • R1R2
A

Anti-f will react with cells that carry c and e on the same Rh polypeptide. No other listed genotypes produce and Rh polypeptide that carries both c and e.

72
Q
  1. A patient’s red blood cells gave the following reaction:

Anti-D

Anti-C

Anti-E

Anti-c

Anti-e

Anti-f

+

+

+

+

+

0

The most probable genotype of the patient is:

  1. R1R2
  2. R2r”
  3. Rzr
  4. RzRz
A

Nonreactivity with anti-f indicates that cells so not have an Rh polypeptide that possesses both c and e, which is necessary to type as f+. R1R2 is the most likely genotype.

73
Q

Anti-N is identified in a patient’s serum. If random crossmatches are performed on 10 donor units, how many would be compatible?

  • 0
  • 3
  • 7
  • 10
A

The N antigen is lacking in 30% of the Caucasian population.

74
Q

A woman types Rh-positive. She has an anti-c titer of 32 at AHG. Her baby has a negative DAT and is not affected by hemolytic disease of the newborn. What is the father’s most likely Rh phenotype?

  • rr
  • r”r
  • R1r
  • R2
A

The baby appears to lack c since no HDFN was evident. The mom is most likely R1R1, so had to pass R1 onto the baby. The father must have passed on an Rh gene that also did not produce c. Given the choices, the father has to be R1r.

75
Q

Which of the following red cell typings are most commonly found in the African American donor population?

  • Lu(a-b-)
  • Jk(a-b-)
  • Fy(a-b-)
  • K-k-
A

The Fy(a-b-) phenotype occurs in 68% of the population of african descent, but is extremely rare in the other ethnic backgrounds. Lu(a-b-), Jk(a-b-) and K-k- are very rare in all ethnic backgrounds.

76
Q

Four units of blood are needed for elective surgery. The patient’s serum contains anti-C, anti-e, anti-Fya and anti-Jkb. Which of the following would be the best source of donor blood?

  • Test all units in current stock
  • Test 100 group O, Rh-negative donors
  • Test 100 group compatible donors
  • Rare donor files
A

The frequency of compatible donors the patient can be calculated by multiplying the percentage of the population that is e-C- x Fy(a-) x Jk(b-). The blood supplier’s immunohematology reference lab may have units in stock or can request blood from other IRL’s through the American Rare Donor program.

77
Q
  1. A donor is tested with Rh antisera with the following results:

Anti-D

Anti-C

Anti-E

Anti-c

Anti-e

Rh control

+

+

0

+

+

0

What is his most probable Rh genotype?

  1. R1R1
  2. R1r
  3. R0r
  4. R2r
A

The most likely haplotype is DCe/dce

78
Q
  1. A family has been typed for HLA because 1 of the children needs a stem cell donor. Typing results are listed below:

Father:

A1,3;B8,35

Mother:

A2,23;B12,18

Child #1

A1,2;B8,12

Child #2

A1,23;B8,18

Child #3

A3,23;B18,?

What is the expected B antigen in child #3?

  1. A1
  2. A2
  3. B12
  4. B35
A

From the first 2 children it can be determined the mom has the haplotypes A2B12 and A23B18. The dad has the haplotypes A1B3 nad A3B35. The expected B antigen in child #3 is B35.

79
Q

Which of the following is the best source of HLA-compatible platelets?

  • Mother
  • Father
  • Siblings
  • Cousins
A

If an exact match of HLA-A and HLA-B antigens is necessary, siblings would be the most likely match, since siblings may have received the same haplotypes from the parents.

80
Q

A patient is group O, Rh-negative with an anti-D and anti-K, in her serum. What percentage of the general caucasian donor population would be compatible with this patient?

  • 0.5
  • 2.0
  • 3.0
  • 6.0
A

Determination of compatibility can be determined by multiplying the percentage of compatibility of each antigen. 46% of the population is group O, 15% are D-, and 91% are K-. 0.46*0.15*0.91=0.06

81
Q
  1. The observed phenotype in a particular population are:

Phenotype

Number of Persons

Jk(a+b-)

122

Jka(a+b+)

194

Jka(a-b+)

84

What is gene frequency of Jka in this population?

  1. 0.31
  2. 0.45
  3. 0.55
  4. 0.6
A

Use the Hardy-Weinberg equation: p^2+2pq+q^2=1.0 In this example, p^2 is the homozygous population, Jk(a+b-). The square root of p^2=p, which is the gene frequency of Jka in this population. Out of 400 people, 112 or 30% are homozygous. The square root of 0.30=0.55.

82
Q

In a random population, 16% of the people are Rh-negative (rr). What percentage of the Rh-positive population is heterozygous for r?

  • 36%
  • 48%
  • 57%
  • 66%
A

The Hardy-Weinberg equation states p+q=1.0 When the equation is expanded, it is p2+2pq+q2=1.

83
Q

In relationship testing, a “direct exclusion” is established when a genetic marker is:

  • Absent in the child, but present in the mother and alleged father
  • Absent in the child, present in the mother and absent in the alleged father
  • Present in the child, absent in the mother and present in the alleged father
  • Present in the child, but absent in the mother and the alleged father
A

When a marker is in a child that the mother and alleged father do not have, the alleged father can not be the biological father of the child. This is direct exclusion

84
Q
  1. Relationship testing produces the following red cell phenotyping results:

ABO

Rh

Alleged father:

B

D+C-c+E+e-

Mother:

O

D+C+E-c-e+

Child:

O

D+C+E-c+e+

What conclusions may be made?

  1. There is no exclusion of paternity
  2. Paternity may be excluded on the basis of ABO typing
  3. Paternity may be excluded on the basis of Rh typing
  4. Paternity may be excluded on the basis of both ABO and Rh typing
A

The child’s genotype does not include E. The alleged father is homozygous for E. If he was the father the child would also have E. The father can be excluded from paternity

85
Q

In a relationship testing case, the child has a genetic marker that is absent in the mother and cannot be demonstrated in the alleged father. What type of paternity exclusion is this know as?

  • Indirect
  • Direct
  • Prior probability
  • Hardy-Weinberg
A

Direct exclusion of paternity is established when a genetic marker is present in the child but is absent from the mother and the alleged father.

86
Q
  1. A patient is typed with the following results:

Patient’s cells with

Patient’s Serum with

anti-A

0

A1 red cells

2+

Anti-B

0

B red cells

4+

Anti-A,B

2+

Ab screen

0

The most probable reason for these findings is the patient group is:

  1. O; confusion due to faulty group O antisera
  2. O; with anti-A1
  3. Ax; With anti-A1
  4. A1; with anti-A
A

Ax cells are more strongly reactive with anti-A,B than with anti-A and the plasma frequently has anti-A1 present.

87
Q

Human blood groups were discovered around 1900 by:

  • Jules Bordet
  • Luis Pasteur
  • Karl Landsteinier
  • PL Mollison
A

The ABO blood group system was discovered by Karl Landstiener

88
Q

Cells of the A3 subgroup will:

  • React with Dolichos Biflorus
  • bE-with Anti-A
  • Give a mixed field reaction with Anti-A,B
  • bE-with anti-H
A

Mixed field reactivity with anti-A and anti-A,B is a typical finding for A3 subgroups

89
Q

The enzyme responsible for conferring H activity on the red cell membrane is alpha-:

  • Galactosyl transferase
  • N-acetygalactosaminyl transferase
  • L-fucosyl transferase
  • N-acetylglucosaminyl transferase
A

Fucose is the immunodominant sugar for H

90
Q

Even in the absence of prior transfusion or pregnancy, individuals with the Bombay phenotype (Oh) will always have naturally occurring:

  • Anti-Rh
  • Anti-Ko
  • Anti-U
  • Anti-H
A

Bombay phenotypes (Oh) lack H antigen on their red cells, and produce naturally occurring anti-H in their serum.

91
Q

The antibody in the Lutheran system that is best detected at lower temperature is:

  • Anti-Lua
  • Anti-Lub
  • Anti-Lu3
  • Anti-Luab
A

Most examples of anti-Lua agglutinate saline suspended cells. Most examples of anti-Lub are IgG and reacts at 37C. Anti-Lu3 usually reacts at the AHG phase as does anti-Luab.

92
Q

Which of the following antibodies is neutralized by pooled human plasma?

  • Anti-Kn
  • Anti-Ch
  • Anti-Yka
  • Anti-Csa
A

Anti-Ch and anti-Rg react at IAT with trace amounts of C4 (a component of complement) present on normal RBCs. The Ch and Rg substance is found soluble in plasma. Neutralization studies with pooled plasma can help confirm the antibody reactivity in a patient’s sample. If test procedures are used to coat cells with C4, a patient with anti-Ch or anti-Rg may agglutinate the cells directly.

93
Q

Anti-Sda is strongly suspected if:

  • The patient has been previously transfused
  • The agglutinates are mixed-field and refractile
  • The patient is group A or B
  • Only a small number of panel cells are reactive
A

Anti-Sda is an antibody to a high-prevalence antigen, which varies in strength from person to person. Most examples of anti-Sda characteristically present as small, mixed-field refractile agglutinates that may have a shiny appearance when observed microscopically after the antiglobulin test.

94
Q

HLA antibodies are:

  • Naturally occurring
  • Induced by multiple transfusions
  • Directed against granulocyte antigens only
  • Frequently cause hemolytic transfusion reactions
A

HLA antibodies are formed in response to pregnancy, transfusions or transplantation and are therefore not naturally occurring. They are associated with febrile nonhemolytic transfusion reactions and TRALI. They are directed against antigens found on granulocytes and other cells such as platelets.

95
Q

Genes of the major histocompatibility complex (MHC):

  • Code for HLA-A, HLA-B, and HLA-C antigens only
  • Are linked to genes in the ABO system
  • Are the primary genetic sex-determinants
  • Contribute to the coordination of cellular and humoral immunity
A

MHC consists of both class I and class II HLA antigens. Discrimination of self from nonself is the primary function of the HLA system and involves many immune responses.

96
Q

Isoimmunization to platelet antigen HPA-1a and the placental transfer of maternal antibodies would be expected to cause newborn:

  • Erythroblastosis
  • Leukocytosis
  • Leukopenia
  • Thrombocytopenia
A

HPA-1a is a platelet specific antigen, which is the most common cause of neonatal alloimmune thrombocytopenia. Treatment consists of IVIG.

97
Q

Saliva from which of the following individuals would neutralize an autoanti-H in the serum of a group A, Le(a-b+) patient?

  • Group A, Le(a-b-)
  • Group A, Le(a+b-)
  • Group O, Le(a+b-)
  • Group O, Le(a-b+)
A

SBB ASCP (8 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions