MZUZU UNIVERSITY
FACULTY OF HEALTH SCIENCES
DEPARTMENT OF BIOMEDICAL SCIENCES
BACHELOR OF SCIENCE IN BIOMEDICAL SCIENCES
END OF SEMESTER EXAMINATION
BLOOD TRANSFUSION - BMS 4801
DATE : Monday, June 30, 2014
TIME : 3 Hours
INSTRUCTIONS
This paper comprises 3 sections
Section A:
Multiple Choice, True or False questions and matching (answer all questions)
Section B:
Short Essays (answer any four questions; all questions carry equal marks)
Section C:
Long Essays (answer one question; all questions carry equal marks)
- There is no negative marking
- Use the answer sheet provided when answering multiple choice questions
- Do not use one sheet of paper for more than one short essay or long essay
question. Start a new question on a new sheet of paper.
- Use your examination numbers only. Do not write your names on the answer
sheets
- Ensure that your handwriting is legible.
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SECTION A: (60 marks)
Answer ALL questions in this section
Make one choice and write it in on the answer sheets provided
Time allocated: 1.5 hours
1. Blood collected in CPD can only be stored for
(a) 28 days (b) 21 days (c) 35 days (d) 42 days
2. This is not responsible for causing a false negative result in the indirect
antiglobulin test
a) Inadequate washing of the red cells
b) inadequate incubation time
c) Presence of particulate matter such as dust
d) All of the above
3. Fresh frozen plasma can be stored at
(a) 4 degrees celcious for 48 hours
(b) 22 degrees celcious for 6 months
(c) -40 degrees celcious for 3 years
(d) -30 degrees celcious for 1 year
4. The Betke-Keihauer Test slide at the time of reading will show dark cells
(stained) and unstained ‘ghost cells’. What are these ghost cells?
a) Fetal cells
b) Maternal cells
c) heamolysed cells
d) Sensitised cells
5. The length of the window period is not affected by
(a) the nature of the micro-organism
(b) the size of the host
(c) the quantity of the micro-organisms infused into the host
(d) the test kits used
6. Blood collected in 500 IU heparin must be used within
(a) 6 hours (b) 12 hours (c) 24 hours (d) 48 hours
7. Platelets are stored at high temperatures
(a) to activate them for use
(b) to prevent them from becoming infected.
(c) if stored at lower temperatures they die
(d) none of the above.
8. Compatibility testing will
(a) detect most irregular antibodies on the donor’s red cells which are reactive
with the patient’s serum
(b) prove that the donor’s plasma was free from irregular antibodies
(c) detect most ABO typing errors
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(d) ensure complete safety of the transfusion
9. Febrile non-heamolytic reactions are caused by a reaction of:
(a) Patient antibodies against proteins in donor blood
(b) Donor antibodies against patient proteins
(c) Patient white cell antibodies against donor white cells
(d) Donor white cell antibodies against patient white cells
10 The finding below that would not be expected in an IgG mediated
delayed transfusion reaction is
(a) fever (b) anaemia (c) jaundice (d) intravascular haemolysis
11 All immunoglobulins have the same basic structure, which consists of
a) 4 heavy chains
b) 4 light chains
c) 4 heavy chains and 4 light chains
d) 2 heavy chains and 2 light chains
12 Regarding blood groups
(a) MNS blood group system is associated with a degree of immunity to
malaria
(b) None of the antigens are destroyed by enzyme
(c) Blood group B is produced by the addition of galactose to a terminal
galactose of the H substance
(d) 50% of the population of Malawi are secretors of ABO substances
13. When issuing cryoprecipitate
(a) product of the same blood group as the patient should be given
(b) Group O cryoprecipiate should be used as a universal donor
(c) Always perform an emergency cross-match
(d) All of the above
14 The ABO gene is on chromosome
(a) 1 (b) 22 (c) 9 (d) 10
15 Delayed haemolytic reactions
a) are typically caused by ABO incompatibility
b) can be prevented by carrying out an IAT cross-match technique.
c) the involved antibody is identified by carrying out an antibody screen.
d) cannot be caused by Rh antibodies.
16. Haemolysis during typing or cross matching procedures can be
suspected by:
a) The greenish colour of the supernatant
b) Unexplained loss of many red cells
c) Microscopic means
d) Loss of supernatant
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17 To which blood type can persons with blood group AB donate their blood
(a) type A
(b) type B
(c) type AB
(d) all of the above
18 Reverse typing is not necessary with cord blood because
(a) New borns have no titres of isoantibodies
(b) cord blood does not have satisfactory serum
(c) of contamination from mother’s blood
(d) all of the above
19. Direct antiglobulin test is used to detect
(a) in vitro reaction of antigen-antibody
(b) in vitro sensitization of antibodies
(c) in vivo reaction of antigen-antibody
(d) all of the above
20 For routine cross matching, the antiglobulin test tube method requires
(a) 60 minutes incubation at 37º c
(b) 30 minutes incubation at 37º c
(c) 15 minutes incubation at 37º c
(d) 15 minutes incubation at 57º c
21 Which blood group was not discovered by Karl Landsteiner
(a) A
(b) B
(c) AB
(d) O
22 The dose for platelet concentrates is
(a) 1 unit per 20kg body weight
(b) 1 unit per 10kg body weight
(c) 20ml/kg body weight
(d) 10ml/kg body weight
23 Which statement is true about ABO antibodies
(a) They are predominantly immune IgG antibodies
(b) They react strongly at 4 degrees celcious
(c) They usually give weak reactions
(d) They are available on red cells only
24 Which Rh antigen is never expressed and as such has no
corresponding anti-sera
(a) Rhc
(b) Rhe
(c) Rhd
(d) None of the above
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25 Regarding weak D:
(a) weak D positives are homozygous for the D gene.
(b) Weak D positives are heterozygous for the D gene.
(c) Weak D positive individuals are weak and frail.
(d) None of the above
26 Which gene combination has the RhC antigen.
(a) Rr (b) RR (c) r’r’ (d)r’’r’’
27 In the preservative solution SAGM, the S stands for
(a) Saline
(b) Sodium
(c) Selenium
(d) None of the above
28. About the RhD antigen
(a) It produces naturally occurring IgM antibodies
(b) It is common in Caucasian populations at about 15%
(c) It is least common in black populations at about 1%
(d) It is the third most antigenic after the ABO antigens and the Rhc
29 The most frequent cause for ABO transfusion reaction is:
(a) clerical error
(b) previous transfusions
(c) previous pregnancy
(e) All of the above
30 The minimum required titres of a strong reacting anti-A when reacted with
A and AB cells are:
(a) 1/240 with A cells and 1/60 with AB
(b) 1/128 with A cells and 1/64 with AB cells
(c) 1/64 with A cells and 1/128 with AB cells
(d) None of the above
31 Grouping sera for use on a tile should give strong reactions within
(a) 5 minutes
(b) 10 minutes
(c) 1 minute
(d) I hour
32 The first blood bank was established in 1932 in the
(a) United States of America
(b) England
(c) Russia
(d) Austria
33 Monoclonal antibodies used for blood typing are prepared from:
(a) sensitized human subjects
(b) cell lines in vitro
(c) both A and B
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(d) Only from sensitized RhD negative women
34 Whole blood is stored at 2-6 degrees celcious
(a) To reduce the red cell metabolic rate
(b) To prevent the cells from freezing
(c) To prevent proliferation of microbes
(d) All of the above
35 The dose when transfusing plasma is
(a) 1 unit per adult person
(b) 15-20mls/kg body weight in children only
(c) 15-20ml/kg body weight for everyone
(d) 6 units per adult person
36 Regarding transmission of transfusion transmissible infections
(a) Cytomegaloviruses can be transmitted through blood transfusion
(b) Due to lack of cells, platelet concentrates do not transmit HIV
(c) Hepatitis B is not transmitted through some blood products such as
cryoprecipitate
(d) Epstein Bar Virus is not transmitted through blood transfusion
37 Antigen collections are said to be high frequency when they occur in
which percentage of the population
(a) More than 75%
(b) More than 90%
(c) More than 99%
(d) More than 50%
38 Which human blood group system corresponds to the rhesus monkey
blood group system?
(a) Rh blood group system
(b) The LW blood group system
(c) The Lewis blood group system
(d) The Lutheran blood group system
39 The indirect antiglobulin test (IAT) is used when
(a) investigating haemolytic disease of the newborn
(b) investigating autoantibodies
(c) Detecting and identifying RBC allo-antibodies
(d) None of the above
State whether the statements below are true or false
40 Fresh frozen plasma is used to treat thrombotic thrombocytopaenic purpura.
41 The locus for the Rh gene is on chromosome 1
42 Displayed blood bank refrigerator temperature is the only temperature read
and recorded when monitoring storage temperature for whole blood
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43 Antibodies are produced against every foreign antigen introduced into the
body.
44 Each IgM antibody has 8 binding sites.
45 Specificity for an antisera means ability to give unequivocal positive reactions.
46 High molecular weight colloids can cause rouleaux formation during cross-
matching
47 Laboratory made 0.85% saline must be used within 2 weeks of preparation.
48 Ionic strength of the suspending medium does not affect the primary stage of
agglutination
49 Simply defined, quality means ‘fit for the purpose’
50 Rh antigens are not destroyed by enzyme
51 Match the items on the left with the associated items on the right. The
items on the right may be used once or more or none at all. (10 marks)
A Precipitates when thawed at 4oC -CDE/cDe
B Du testing not required -Universal blood donor
C Blood group AB -Duffy blood group
D Not transmitted by blood banked for 72 hours -Form of treatment for HDN
E Is not transmitted through blood transfusion -cdE/cde
F r’’r -patients
G RzRo -Factor viii
H Plasmapheresis -Syphilis
I Exchange transfusion -CDE/CDe
J Confers immunity to malaria -blood donors
-gonorrhoea
-universal plasma donor
-Only plasma is removed from
the donor
SECTION B: SHORT ESSAYS
Answer any FOUR questions in this section.
Time allocated 1 hour
1 (a) Explain why haemolytic disease of the new born does not usually
occur with the first pregnancy (8 marks)
(b) What is the principle of the Kleihauer Test (2 marks)
2 Write short notes on recruiting voluntary non-remunerated blood donors
(10 marks)
3 Choose any three non-infectious transfusion reactions and describe their
postulated pathophysiology (10 marks)
4 Write short notes on quality assurance (10 marks)
5 Describe the procedure for performing the indirect antiglobulin test
(10 marks)
6 Describe the factors that affect red cell agglutination. (10 marks)
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SECTION C: LONG ESSAYS
Answer ONE question from this section
Time allocated: 30 minutes
1 Explain in detail the strategies that must be implemented to ensure blood
safety in any given country. (20 marks)
2 A group of students are involved in a hot argument about the various types of
blood donors. Some argue that all blood donors are the same as they all
donate blood for transfusion, others argue that some types of blood donors
are less desirable than others. They then approach you as a biomedical
scientist to resolve the argument. What will be your response and why?
(20 marks)
3 Describe the various possible sources of errors in the laboratory and in the
ward that can lead to a patient receiving a wrong blood product. (20 marks)
