MLS Blood Banking & Transfusion Medicine 1 — Questions and Answers
Question 1: Which blood type is considered the universal donor for packed red blood cells?
- A negative
- O negative (Correct answer)
- AB positive
- B negative
Correct answer: O negative
O negative red blood cells lack A, B, and Rh D antigens, making them compatible with recipients of any blood type.
Question 2: A patient with Type A blood has which naturally occurring antibody in their serum?
- Anti-A
- Anti-B (Correct answer)
- Anti-A and Anti-B
- No ABO antibodies
Correct answer: Anti-B
Type A individuals produce Anti-B antibodies per Landsteiner's rule, which states that individuals form antibodies against ABO antigens they do not possess.
Question 3: Which crossmatch method is most sensitive for detecting clinically significant alloantibodies?
- Immediate spin crossmatch
- Electronic crossmatch
- Antiglobulin (indirect) crossmatch (Correct answer)
- Saline agglutination crossmatch
Correct answer: Antiglobulin (indirect) crossmatch
The antiglobulin (indirect) crossmatch detects IgG antibodies and complement that coat red cells without immediate agglutination, identifying clinically significant antibodies capable of causing hemolysis.
Question 4: A positive Direct Antiglobulin Test (DAT) indicates that:
- The patient has unexpected antibodies free in serum
- The patient's red blood cells are coated with IgG or complement in vivo (Correct answer)
- ABO incompatibility exists between donor and recipient
- The patient is Rh D positive
Correct answer: The patient's red blood cells are coated with IgG or complement in vivo
A positive DAT demonstrates that the patient's circulating red blood cells are sensitized (coated) with IgG antibodies or complement components in vivo.
Question 5: At what temperature and conditions must platelets be stored in the blood bank?
- 1–6°C with no agitation
- −18°C or colder
- 20–24°C with continuous gentle agitation (Correct answer)
- 4°C with intermittent agitation
Correct answer: 20–24°C with continuous gentle agitation
Platelets must be stored at 20–24°C with continuous gentle agitation to maintain metabolic activity, pH, and prevent platelet clumping.
Question 6: Which Rh antigen is considered the most clinically significant and immunogenic?
- Rh C
- Rh D (Correct answer)
- Rh E
- Rh c
Correct answer: Rh D
The D antigen is the most immunogenic of the Rh antigens and is the primary antigen responsible for hemolytic disease of the fetus and newborn (HDFN) and hemolytic transfusion reactions.
Question 7: Which blood type is the universal recipient for packed red blood cells?
- O positive
- A positive
- B positive
- AB positive (Correct answer)
Correct answer: AB positive
AB positive individuals have A, B, and D antigens on their red cells and no ABO antibodies in serum, allowing them to receive red cells from any ABO/Rh blood group.
MLS Blood Banking & Transfusion Medicine 1
Which blood type is considered the universal donor for packed red blood cells?