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The minimum hemoglobin concentration in a fingerstick from a male blood donor is:
a. 12.0 g/dL (120 g/L)
b. 12.5 g/dL (125 g/L)
c. 13.5 g/dL (135 g/L)
d. 15.0 g/dL (150 g/L)
b. All donors, regardless of sex, require a minimum hemoglobin of 12.5 g/dL (125 g/L). The value must not be performed on an earlobe stick.
A cause for permanent deferral of blood donation is:
a. diabetes
b. residence in an endemic malaria region
c. history of jaundice of uncertain cause
d. history of therapeutic rabies vaccine
c. 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.
Which of the following prospective donors would be accepted for donation?
a. 32-year-old woman who received a transfusion in a complicated delivery 5 months previously
b. 19-year-old sailor who has been stateside for 9 months and stopped taking his anti-malarial medication 9 months previously
c. 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
d. 45-year-old woman who has just recovered from a bladder infection and is still taking antibiotics
c. 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 37.5°C or 99.5°F.
Which one of the following constitutes permanent rejection status of a donor?
a. a tattoo 5 months previously
b. recent close contact with a patient with viral hepatitis
c. 2 units of blood transfused 4 months previously
d. confirmed positive test for HBsAg 10 years previously
d. A positive test for HbsAg at any time is an indefinite deferral.
According to AABB standards, which of the following donors may be accepted as a blood donor?
a. traveled to an area endemic for malaria 9 months previously
b. spontaneous abortion at 2 months of pregnancy, 3 months previously
c. resides with a known hepatitis patient
d. received a blood transfusion 22 weeks previously
b. A woman who had a spontaneous abortion at 2 months of pregnancy, 3 months previously would be acceptable. A donor is acceptable if she has not been pregnant in the previous 6 weeks.
Below are the results of the history obtained from a prospective female blood donor:
Age: 16
Temperature: 99.0"F (37.2°C)
Hct: 36%
History: tetanus toxoid immunization 1 week previously
How many of the above results excludes this donor from giving blood for a routine transfusion?
a. none
b. 1
c. 2
d. 3
b. The Hct must be >38%, A donor may be l6 unless state law differs. Temperature must not exceed 99.5°C/37.5°C, blood pressure must be <180 mmHg systolic and <100 mmHg diastolic, pulse 50-100 unless an athlete (which can be lower). Toxoids and vaccines from synthetic or killed sources have no deferral.
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:
a. 150 x 10^3 / µL (150 x 10^9 / L)
b. 200 x 10^3/ µL (200 x 10^9/ L)
c. 250 x 10^3 / µL (250 x 10^9 / L)
d. 300 x 10^3 / µL (300 x 10^9 / L)
a. The minimum platelet count required for frequent repeat donors is 150 x 10^3/µL (150 x 10^9/L). A platelet count is not required prior to the first donation or if the interval between donations is at least 4 weeks.
Prior to blood donation, the intended venipuncture site must be cleaned with a scrub' solution containing:
a. hypochlorite
b. isopropyl alcohol
c. 10% acetone
d. PVP iodine complex
d. 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.
All donor blood testing must include:
a. complete Rh phenotyping
b. anti-CMV testing
c. direct antiglobulin test
d. serological test for syphilis
d. Testing for syphilis was the first mandated donor screening test for infectious disease and is still part of donor screening.
During the preparation of Platelet Concentrates from Whole Blood, the blood should be:
a. cooled towards 6°C
b. cooled towards 20°-24°C
c. warmed to 37°C
d. heated to 57°C
b. Platelets are prepared and stored at
20°-24°C for optimum function.
The most common cause of post-transfusion hepatitis can be detected in donors by testing for:
a. anti-HCV
b. HBsAg
c. anti-HAV IgM
d. anti-HBe
b. The most common post-transfusion 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.
The Western blot is a confirmatory test for the presence of:
a. CMV antibody
b. anti-HIV-1
c. HBsAg
d. serum protein abnormalities
b. Western blot uses purified HIV proteins to confirm reactivity in samples whose screening test for anti-HIV is positive.
The test that is currently used to detect donors who are infected with the AIDS virus is:
a. anti-HBc
b. anti-HIV 1,2
c. HBsAg
d. ALT
b. The causative agent for AIDS is the human immunodeficiency virus types 1 and 2.
A commonly used screening method for anti-HIV-1 detection is:
a. latex agglutination
b. radioimmunoassay (RIA)
c. thin-layer-chromatography (TLC)
d. enzyme-labeled immunosorbent assay (ELISA)
d. The enzyme-labeled immunosorbent assay (ELISA) method is a very sensitive method employed to screen donors for markers of transfusion-transmitted viruses.
Rejuvenation of a unit of Red Blood Cells is a method used to:
a. remove antibody attached to RBCs
b. inactivate viruses and bacteria
c. restore 2,3-DPG and ATP to normal levels
d. filter blood clots and other debris
c. Rejuvenation of RBCs uses additives to restore or enhance 2,3-DPG and ATP levels.
A unit of packed cells is split into 2 aliquots under closed sterile conditions at 8 AM. The expiration time for each aliquot is now:
a. 4 PM on the same day
b. 8 PM on the same day
c. 8 AM the next morning
d. The original date of the unsplit unit
d. Sterile docking devices allow entry into donor units without affecting the expiration date of the product.
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:
a. 6 hours
b. 12 hours
c. 5 days
d. 35 days
d. Sterile docking devices allow entry into donor units without affecting the expiration date of the product.
When platelets are stored on a rotator set on an open bench top, the ambient air temperature must be recorded:
a. once a day
b. twice a day
c. every 4 hours
d. every hour
c. If storage devices do not have automated temperature recording, temperature must be
manually monitored every 4 hours.
Which of the following is the correct storage temperature for the component listed?
a. Cryoprecipitated AHF, 4"C
b. Fresh Frozen Plasma (FFP), -20"C
c. Red Blood Cells, Frozen, -40"C
d. Platelets, 37°C
b. Fresh Frozen Plasma is stored at -18°C or below for 12 months.
A unit of Red Blood Cells is issued at 9:00 AM. At 9:10 AM 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:
a. culture the unit for bacterial contamination
b. discard the unit if not used within 24 hours
c. store the unit at room temperature
d. record the return and place the unit back into inventory
d. 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 < l0°C for up to 30 minutes after removal from the refrigerator.
The optimum storage temperature for Red Blood Cells, Frozen is:
a. -80°C
b. -20°C
c. -12°C
d. 4°C
a. Red Blood Cells, Frozen with 40% glycerol are stored at -65°C or lower.
The optimum storage temperature for Red Blood Cells is:
a. -80°C
b. -20°C
c. -12°C
d. 4°C
d. Red Blood Cells are stored at 1°-6°C.
If the seal is entered on a unit of Red Blood Cells stored at 1°C to 6°C what is the maximum allowable storage period, in hours?
a. 6
b. 24
c. 48
d. 72
b. 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.
The optimum storage temperature for cryoprecipitated AHF is:
a. -20°C
b. -12°C
c. 4°C
d. 22°C
a. Cryoprecipitated AHF is stored at -18"C or lower.
Cryoprecipitated AHF must be transfused within what period of time following thawing and pooling?
a. 4 hours
b. 8 hours
c. 12 hours
d. 24 hours
a. Cryoprecipitate must be transfused within 4 hours of pooling.
The optimum storage temperature for platelets is:
a. -20°C
b. -12°C
c. 4°C
d. 22°C
d. The required temperature for storage of platelets is 20°-24°C.
Platelets prepared in a polyolefin type container, stored at 22°-24°C in 50 ml of plasma, and gently agitated can be used for up to:
a. 24 hours
b. 48 hours
c. 3 days
d. 5 days
d. Whole Blood-derived platelets are stored at 20°-24°C with continuous gentle agitation. Platelets prepared by the PRP method may be stored for up to 5 days.
According to AABB standards, Fresh Frozen Plasma must be infused within what period of time following thawing?
a. 24 hours
b. 36 hours
c. 48 hours
d. 72 hours
a. Per AABB standards, thawed FFP should be stored at 1°-6°C for no more than 24 hours.
Cryoprecipitated AHF, if maintained in the frozen state at -18"C or below, has a shelf life of:
a. 42 days
b. 6 months
c. 12 months
d. 36 months
c. Cryoprecipitate has a shelf life of 12 months in the frozen state.
Once thawed, Fresh Frozen Plasma must be transfused within:
a. 4 hours
b. 8 hours
c. 12 hours
d. 24 hours
d. Once thawed, FFP is stored at 1°-6°C for up to 24 hours.
An important determinant of platelet viability following storage is:
a. plasma potassium concentration
b. plasma pH
c. prothrombin time
d. activated partial thromboplastin time
b. The pH of platelets should be maintained at 6.2 or above throughout the storage period.
In the liquid state, plasma must be stored at:
a. 1°C - 6°C
b. 22°C
c. 37°C
d. 56°C
a. The required temperature for storage of
thawed plasma is 1°C - 6°C.
During storage, the concentration of 2,3-diphosphoglycerate (2,3-DPG) decreases in a unit of:
a. Platelets
b. Fresh Frozen Plasma
c. Red Blood Cells
d. Cryoprecipitated AHF
c. 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.
Cryoprecipitated AHF:
a. is indicated for fibrinogen deficiencies
b. should be stored at 4•c prior to administration
c. will not transmit hepatitis B virus
d. is indicated for the treatment of hemophilia B
a. Cryoprecipitate is used primarily for fibrinogen replacement. It is stored at room temperature (20"-24"C) after thawing and must be infused within 6 hours. If pooled with other cryo units, it must be infused within 4 hours.
Which apheresis platelets product should be irradiated?
a. autologous unit collected prior to surgery
b. random stock unit going to a patient with DIC
c. a directed donation given by a mother for her son
d. a directed donation given by an unrelated family friend
c. Blood products from blood relatives containing viable lymphocytes must be irradiated to inhibit the proliferation of T-cells and subsequent GVHD.
Irradiation of a unit of Red Blood Cells is done to prevent the replication of donor:
a. granulocytes
b. lymphocytes
c. red cells
d. platelets
b. Irradiation inhibits proliferation of T lymphocytes.
Plastic bag overwraps are recommended when thawing units of FFP in 37°C water baths because they prevent:
a. the FFP bag from cracking when it contacts the warm water
b. water from slowly dialyzing across the bag membrane
c. the entry ports from becoming contaminated with water
d. the label from peeling off as the water circulates in the bath
c. FFP thawed in a water bath should be protected so that entry ports are not contaminated with water. One can may use a plastic overwrap or keep ports above the water level.
Which of the following blood components must be prepared within 8 hours after phlebotomy?
a. Red Blood Cells
b. Fresh Frozen Plasma
c. Red Blood Cells, Frozen
d. Cryoprecipitated AHF
b. Fresh Frozen Plasma (FFP) must be separated and frozen within 8 hours of Whole Blood collection.
Cryoprecipitated AHF contains how many units of Factor VIII?
a. 40
b. 80
c. 130
d. 250
b. Cryoprecipitate contains at least 80 units of AHF.
Which of the following blood components contains the most Factor VIII concentration relative to volume?
a. Single-Donor Plasma
b. Cryoprecipitated AHF
c. Fresh Frozen Plasma
d. Platelets
b. Cryoprecipitated AHF contains at least 80 IU of Factor VIII concentrated in about 10 mL of plasma.
The most effective component to treat a patient with fibrinogen deficiency is:
a. Fresh Frozen Plasma
b. Platelets
c. Fresh Whole Blood
d. Cryoprecipitated AHF
d. 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.
A blood component prepared by thawing Fresh Frozen Plasma at refrigerator temperature and removing the fluid portion is:
a. Plasma Protein Fraction
b. Cryoprecipitated AH F
c. Factor IX Complex
d. FP24
b. Cryoprecipitate is the fraction of plasma proteins that precipitate when FFP is slowly thawed at 1°-6-C.
Upon inspection, a unit of platelets is noted to have visible clots, but otherwise appears normal. The technologist should:
a. issue without concern
b. filter to remove the clots
c. centrifuge to express off the clots
d. quarantine for Gram stain and culture
d. Clots in the unit may indicate contamination.
According to AABB Standards, at least 90% of all Apheresis Platelets units tested shall contain a minimum of how many platelets?
a. 5.5 X 10^10
b. 6.5 X 10^10
c. 3.0 X 10^11
d. 5.0 x l0^11
c. Per AABB standards, at least 90% of platelet pheresis units sampled must contain at least 3.0 x 10^11 platelets.
According to AABB Standards, Platelets prepared from Whole Blood shall have at least:
a. 5.5 x 10^10 platelets per unit in at least 90% of the units tested
b. 6.5 x 11^10 platelets per unit in 90% of the units tested
c. 7.5 x 10^10 platelets per unit in 100% of the units tested
d. 8.5 x 10^10 platelets per unit in 95% of the 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 10^10 platelets.
Which of the following is proper procedure for preparation of Platelets from Whole Blood?
a. light spin followed by a hard spin
b. light spin followed by 2 hard spins
c. 2 light spins
d. 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.
According to AABB standards, what is the minimum pH required for Platelets at the end of the storage period?
a. 6.0
b. 6.2
c. 6.8
d. 7.0
b. 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.
According to AABB standards, Platelets must be:
a. gently agitated if stored at room temperature
b. separated within 12 hours of Whole Blood collection
c. suspended in sufficient plasma to maintain a pH of 5.0 or lower
d. prepared only from Whole Blood units that have been stored at 4°C for 6 hours
a. Per AABB standards, store Platelets at 20-24°C with continuous agitation. Platelets must be separated from Whole Blood units and maintained at a temperature of at least 20°C. The pH must be at least 6.2 at the end of the storage time.
A unit of Whole Blood-derived (random donor) Platelets should contain at least:
a. 1.0 x 10^10 platelets
b. 5.5 x 10^10 platelets
c. 5.5 x 10^11 platelets
d. 90% of the platelets from the original unit of Whole Blood
b. Whole blood-derived (random donor) Platelets should contain at least 5.5 x 10 10 platelets, be stored with continuous agitation at 20-24°C, and have a pH of 6.2 or higher when tested at the end of the storage period.
Platelets prepared by apheresis should contain at least:
a. 1 x 10^10 platelets
b. 3 x 10^10 platelets
c. 3 x 10^11 platelets
d. 5 x 10^11 platelets
c. Apheresis (single donor) Platelets should contain at least 3.0 x 10^11 platelets, be stored with continuous agitation at 20°-24°C, and have a pH of 6.2 or higher when tested at the end of the storage period.
Leukocyte-Reduced Red Blood Cells are ordered for a newly diagnosed bone marrow candidate. What is the best way to prepare this product?
a. crossmatch only CMV-seronegative units
b. irradiate the unit with 1,500 rads
c. wash the unit with saline prior to infusion
d. transfuse through a Log^3 leukocyte-removing filter
d. Newly diagnosed bone marrow candidates are at great risk for severe sequelae of CMV infections. Infection 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.
Of the following blood components, which one should be used to prevent HLA alloimmunization of the recipient?
a. Red Blood Cells
b. Granulocytes
c. Irradiated Red Blood Cells
d. Leukocyte-Reduced Red Blood Cells
d. Leukoreduction of blood products reduces donor leukocytes to less than 5 x 10^6 and decreases the risk of HLA alloirnrnunization.
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:
a. apheresis
b. autologous
c. homologous
d. fractionation
a. The apheresis process is to remove whole blood, the desired component removed, and the remaining portion of blood returned to the donor/patient
To qualify as a donor for autologous transfusion a patient's hemoglobin should be at least:
a. 8 g/dL (80 g/L)
b. 11 g/dL (110 g/L)
c. 13 g/dL (130 g/L)
d. 15 g/dL (150 g/L)
b. Autologous donors have less stringent criteria than allogeneic donors. Donations must be collected at least 72 hours prior to surgery.
What is/are the minimum pretransfusion testing requirement(s) for autologous donations collected and transfused by the same facility?
a. ABO and Rh typing only
b. ABO/Rh type, antibody screen
c. ABO/Rh type, antibody screen, crossmatch
d. no pre-transfusion 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.
In a quality assurance program, Cryoprecipitated AHF must contain a minimum of how many international units of Factor VIII?
a. 60
b. 70
c. 80
d. 90
c. FDA requires 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 Pactor VIII, corrective action must be taken.
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 9 mL, what is the Factor
VIII content of the bag in IU?
a. 9
b. 18
c. 27
d. 81
d. 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.
The linked HLA genes on each chromosome constitute a(n):
a. allele
b. trait
c. phenotype
d. haplotype
d. The entire set of HLA antigens located on one chromosome is a haplotype.
An individual's red blood cells give the following reactions with Rh antisera:
anti-D: 4+
anti-C: 3+
anti-E: 0
anti-c: 3+
anti-e: 3+
Rh control: 0
The individual's most probable genotype is:
a. DCe/DeE
b. DcE/dce
c. Dce/dce
d. DCe/dce
d. 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 (RH Ce). The RHD gene is more likely inherited with Ce than ce, so the person's most probable genotype is DCe/dce. This genotype is found in 31% of the white and 15% of the black populations.
A blood donor has the genotype: hh, AB. What is his red blood cell phenotype?
a. A
b. B
c. O
d. AB
c. The A and B structures can not be developed since there is no H precursor substance due to the lack of the H gene in the blood donor.
An individual has been sensitized to the k antigen and has produced anti-k. What is her most probable Kell system genotype?
a. KK
b. Kk
c. kk
d. K
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.
Given the =following typing results, what is this donor's racial ethnicity?
Le(a-b-); Fy(a-b-); Js(a+b+)
a. African American
b. Asian American
c. Native American
d. Caucasian
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-).
A mother has the red cell phenotype D+C+E-c-e+ with 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?
a. r'r'
b. r'r
c. R1R1
d. 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 r'r'.
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:
a. anti-c
b. anti-d
c. anti-e
d. 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 thee antigen. The first antibody most likely to develop would be anti-c.
Most blood group systems are inherited as:
a. sex-linked dominant
b. sex-linked recessive
c. autosomal recessive
d. autosomal codominant
d. Blood group genes are autosomal, they are not carried on the sex gene. Whenever the gene is inherited, the antigen is expressed on the red blood cells, which is known as codominant.
The mating of an Xg(a+) man and an Xg(a-) woman will only produce:
a. Xg(a-) sons and Xg(a-) daughters
b. Xg(a+) sons and Xg(a+) daughters
c. Xg(a-) sons and Xg(a+) daughters
d. Xg(a+) sons and Xg(a-) daughters
c. 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.
The red cells of a nonsecretor (se/se) will most likely type as:
a. Le(a-b-)
b. Le(a+b+)
c. Le(a+b-)
d. Le(a-b+)
c. 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 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 Secretor 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-).
Which of the following phenotypes will react with anti-f?
a. rr
b. R1R1
c. R2R2
d. R1R2
a. Anti-f will react with react with cells that carry c and e on the same Rh polypeptide. No other listed genotypes produce an Rh polypeptide that carries both c and e.
Anti-N is identified in a patient's serum. If random crossmatches are performed on 10 donor units, how many would be expected to be compatible?
a. 0
b. 3
c. 7
d. 10
b. The N antigen is lacking in 30% of the Caucasian population.
A woman types as 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?
a. rr
b. r''r
c. R1r
d. R2r
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
Which of the following red cell typings are most commonly found in the African American donor population?
a. Lu(a-b-)
b. Jk(a-b-)
c. Fy(a-b-)
d. K-k-
c. 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.
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?
a. test all units in current stock
b. test 100 group 0, Rh-negative donors
c. test 100 group-compatible donors
d. rare donor file
d. The frequency of compatible donors for this 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 laboratory may have units in stock or can request blood from other IRLs through the American Rare Donor w.
Which of the following is the best source of HLA-compatible platelets?
a. mother
b father
c. siblings
d. cousins
c. 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.
A patient is group 0, Rh-negative with anti-D and anti-Kin her serum. What percentage of the general Caucasian donor population would be compatible with this patient?
a. 0.5
b. 2.0
c. 3.0
d. 6.0
d. Determination of compatibility can be determined by multiplying the percentage of compatibility of each antigen. 46% of the population is group 0, 15% are D-, and 91% are K-. 0.46 x 0.15 x 0.91 = 0.
The observed phenotypes in a particular population are:
Phenotype Number of Persons
Jk(a+b-) 122
Jk(a+b+) 194
Jk(a-b+) 84
What is the gene frequency of J k1 in this population?
a. 0.31
b. 0.45
c. 0.55
d. 0.60
c. Use the Hardy-Weinberg equation: p2 + 2pq + q' = 1.0 In this example, p2 is the homozygous pofulation, Jk(a+b-). The square root of p' = p, which is the gene frequency of Jka in this population. Out of 400 people, 122, or 30% are homozygous. The square root of 0.30 = is 0.55.
In a random population, 16% of the people are Rh-negative (rr). What percentage of the Rh-positive population is heterozygous for r?
a. 36%
b. 48%
c. 57%
d. 66%
b. The Hardy-Weinberg equation states p + q = 1.0. When the equation is expanded, it is p2 + 2pq + q2 = 1.0.
In relationship testing, a "direct exclusion" is established when a genetic marker is:
a. absent in the child, but present in the mother and alleged father
b. absent in the child, present in the mother and absent in the alleged father
c. present in the child, absent in the mother and present in the alleged father
d. present in the child, but absent in the mother and alleged father
d. 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 a direct exclusion.
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 known as?
a. indirect
b. direct
c. prior probability
d. Hardy-Weinberg
b. 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.
Human blood groups were discovered around 1900 by:
a. Jules Bordet
b. Louis Pasteur
c. Karl Landsteiner
d. PL Mollison
c. The ABO blood group system was discovered by Karl Landsteiner.
Cells of the A3 subgroup will:
a. react with Dolichos biflorus
b. bE- with anti-A
c. give a mixed-field reaction with anti-A,B
d. bE- with anti-H
c. Mixed-field reactivity with anti-A and anti-A,B is a typical finding for A3 subgroups.
The enzyme responsible for conferring H activity on the red cell membrane is alpha-:
a. galactosyl transferase
b. N-acetylgalactosaminyl transferase
c. L-fucosyl transferase
d. N-acetylglucosaminyl transferase
c. Fucose is the immunodominant sugar for H.
Even in the absence of prior transfusion or pregnancy, individuals with the Bombay phenotype (Oh) will always have naturally occurring:
a. anti-Rh
b. anti-K0
c. anti-U
d. anti-H
d. Bombay phenotypes (Oh) lack H antigen on their red cells, and produce naturally occurring anti-H in their serum.
The antibody in the Lutheran system that is best detected at lower temperatures is:
a. anti-Lua
b. anti-Luh
c. anti-Lu3
d. anti-Luab
a. Most examples of anti-Lu agglutinate saline suspended cells. Most examples of anti-Lub are IgG and reacts at 37"C. Anti-Lu3 usually reacts at the AHG phase as does anti-Luab
Which of the following antibodies is neutralizahle by pooled human plasma?
a. anti-Kna
b. anti-Ch
c. anti-Yka
d. anti-Csa
b. 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.
Anti-Sda is strongly suspected if:
a. the patient has been previously transfused
b. the agglutinates are mixed field and refractile
c. the patient is group A or B
d. only a small number of panel cells are reactive
b. 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.
HLA antibodies are:
a. naturally occurring
b. induced by multiple transfusions
c. directed against granulocyte antigens only
d. frequently cause hemolytic transfusion reactions
b. HLA antibodies are formed in response to pregnancy, transfusion 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.
Genes of the major histocompatibility complex (MHC):
a. code for HLA-A, HLA-B, and HLA-C antigens only
b. are linked to genes in the ABO system
c. are the primary genetic sex-determinants
d. contribute to the coordination of cellular and humeral immunity
d. 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.
Isoimmunization to platelet antigen HPA-1a and the placental transfer of maternal antibodies would be expected to cause newborn:
a. erythroblastosis
b. leukocytosis
c. leukopenia
d. thrombocytopenia
d. HPA-1a is a platelet specific antigen, which is the most common cause of neonatal alloimmune thrombocytopenia. Treatment consists of IVIG.
Saliva from which of the following individuals would neutralize an auto anti-H in the serum of a group A, Le(a-b+) patient?
a. group A, Le(a-b-)
b. group A, Le(a+b-)
c. group O, Le(a+b-)
d. group O, Le(a-b+)
d. Group O have the most H substance in their saliva. The person must also be a secreter of ABH substances. Due to gene interaction between the secretor gene and
Lewis gene, people who are Le(a-b+) assures H in their saliva.
Inhibition testing can be used to confirm antibody specificity for which of the following antibodies?
a. anti-Lua
b. anti-M
c. anti-Lea
d. anti-Fya
c. Lewis antigens are found soluble in saliva. If saliva containing Lewis substance is added to a sample with anti-Lea, then neutralization occurs. Le(a+) indicator cells added to the test system would be nonreactive. A proper control system is required whenever neutralization studies are performed.
Which of the following Rh antigens has the highest frequency in Caucasians?
a. D
b. E
c. C
d. e
d. The overall incidence of thee antigen is 98%. The overall incidence of c is 80%, D is 85% and E is 30%.
The phenomenon of an Rh-positive person whose serum contains anti-D is best explained by:
a. gene deletion
b. missing antigen epitopes
c. trans position effect
d. gene inhibition
b. Individuals who are partial D are missing epitopes of the D antigen and can develop antibodies toward the epitopes they lack. Since all normal D antigens have all epitopes, the specificity of the person's antibody is anti-D.
When the red cells of an individual fail to react with anti-U, they usually fail to react with:
a. anti-M
b. anti-Leb
c. anti-S
d. anti-P1
c. The U antigen is a high incidence antigen found on the RBCs of all individuals except 1% of African-Americans, who lack glycoprotein B and usually type S-s-U-.
Which of the following red cell antigens are found on glycophorin-A?
a. M,N
b. Lea, Leb
c. S, s
d. P, P1, pk
a. The M and N antigens are found on glycophorin A.
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. I antigen
c. Autoanti-P, a cold-reactive IgG autoantibody described as a biphasic hemolysin, is associated with paroxysmal cold hemoglobinuria.
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. Patients with infectious monucleusis often demonstrate potent examples of anti-i that are transient in nature.
In a case of cold autoimmune hemolytic anemia, the patient's serum would most likely react 4+ at immediate spin with:
a. group A cells, B cells and O cells, but not his own cells
b. cord cells but not his own or other adult cells
c. all cells of a group O cell panel and his own cells
d. only penicillin-treated panel cells, not his own cells
c. Anti-I is commonly found in all individuals, but when it causes hemolysis, the titer may be high and react at all temperatures. Cold agglutinin syndrome is mainly found in lymphoproliferative diseases.
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. Anti-I is associated with cold agglutinin syndrome.
Which of the following is a characteristic of anti-i?
a. often associated with hemolytic disease of the newborn
b. reacts best at room temperature or 4°C
c. reacts best at 37°C
d. is usually IgG
b. Anti-i is an IgM antibody that reacts with cord cells and i adult cells. It is not associated with hemolytic disease of the newborn since IgM antibodies do not cross the placenta.
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. The Kell antigen is highly immunogenic. It is present on the red cells of up to 9% of adults and neonates, and is not affected by enzymes.