This is the sample examination I made for the senior-most staff and candidates. This is really a projective exercise. How far can you go with this? The candidate must specify what additional information he/she needs to complete the assessment.
Name: Badge #:
Date of Exam:
Answer the following questions:
- What is the ABO blood type in each of the following results:
Anti-A | Anti-B | Anti-A,B | A1 cells | B cells | O Cells | ABS | Type? |
0 | 4+ | 3+ | 0 | 0 | 0 | 0 | |
3+ | 0 | 3+ | 1+ | 4+ | 0 | Neg | |
3+ | 1+ | 3+ | 0 | 3+ | 0 | Neg | |
Weak | 0 | 2+ | 0 | 4+ | 0 | Neg | |
0 | 0 | 0 | 4+ | 4+ | 4+ | Pos, all cells | |
Weak | 0 | 0 | 4+ | 4+ | 4+ | Pos, all cells | |
0 | 4+ | 3+ | 4+ | 2+ | 0 | Pos, SCIII | |
Mf | 0 | 0 | 0 | 4+ | 0 | Neg |
ABS = antibody screen; mf = mixed field reaction
Assume that all reactions are the same by both the tube and gel methods.
In the above table, list any discrepancies in each of the testing panels. Describe what additional tests or information, if any, are required to resolve the type.
- What is ABO and D typing in each of the following results?
Anti-A | Anti-B | Anti-D | D-control | A1 cells | B cells | O cells | ABS |
4+ | 4+ | 4+ | 3+ | 4+ | 4+ | 4+ | Pos All cells |
Anti-A | Anti-B | Anti-D | D-control | A1 cells | B cells | O cells | ABS |
0 | 0 | 4+ | 2+ | 4+ | 4+ | 0 | 0 |
Anti-A | Anti-B | Anti-D | D-control | A1 cells | B cells | O cells | ABS |
0 | 0 | 4+ | 2+ | 4+ | 4+ | 2+ | 2+ |
- Using anti-D antisera, explain the difference in reactivity you expect between R1R1 and R2R2 cells.
- Describe at least two antibody specificities associated with a mixed field reaction.
- Describe the discrepancy noted in the following gel reaction and provide a differential diagnosis for the possible cause(s).

- Describe when to use Diluent 1 versus Diluent 2 with the Diamed gel cards.
- There is a critical staffing shortage so you are working the bench when emergency, class I blood is released (O-positive to a 25 year old male victim of a car accident). You receive the specimen and obtain the following set of results:
Anti-A—0, Anti-B—0, A1 cells—4+, B cells—4+, ABS—3+ in SCI/II/III
What actions will you take now? What blood type will you release for subsequent RBC requests? Be explicit!
- An extended phenotype is ordered and Diamed Profile I-II-III cards are used. The following results are obtained on Profile Card III:
M | N | S | S | Fya | Fyb |
0 | 0 | 0 | 0 | 0 | 0 |
Interpret these results.
- Describe the rationale for the prophylactic use of E-c- cells in a patient only showing anti-E.
- A patient develops pain at the infusion site with back pain while a unit of packed RBCs is being transfused. The following results were obtained in the subsequent workup:
Pretransfusion DAT: negative
Post-transfusion DAT: negative
Hemolysis Check—post-transfusion sample—strongly positive
Hemolysis check—pre-transfusion sample—negative
Clerical Check—OK
Pretransfusion ABO/D: B-positive—reverse typing normal
Post-transfusion ABO/D: B-positive—reverse typing normal
Returned unit ABO/D: B-positive
Repeat crossmatch—compatible
Give possible reasons for these findings. What further investigations would you do?
- Interpret the following panels:
48 year old female with septic arthritis and severe anemia (Hgb 6.9 g/dl) and positive autocontrol 2+ (Polyspecific 2+, IgG 2+, C3d nil) and negative antibody screen:
The eluate panel results follow:

Please give your interpretation of the findings. Be sure to specify other information you may require if any.
71 year old female with aortic stenosis admitted for surgical correction, blood type AB positive, antibody screen 2+ positive in all 3 cells, autocontrol negative, no history of recent transfusions.
Extended phenotype is:
C+E+c-e+K-k+Kpa-Kpb+Fya+Fyb-Jka-Jkb+Lea+Leb-P1+M+N-S+s-Lua-Lub+

Note: Cell #1 reacts 2+ at LISS/Coombs using monospecific IgG IgG/Coombs Card.
60 year old male with paraplegia for surgery, B-positive, auto-control negative, no recent transfusion history:


39 year old, pregnant female—no previous history:


36 year old pregnant female, O-positive:
Interpret the panel. What RBC phenotype would you transfuse?


60 year old male with paraplegia for surgery, B-positive, auto-control negative, no recent transfusion history:

