1. Major Blood Groups
ABO

2. Although there are over 600 known red blood cell antigens organized into 22 blood group systems, routine blood typing is usually concerned with only two systems: the ABO and Rh blood group systems. Antibody screening helps to identify antibodies against several other groups of red blood cell antigens.
Some of the other groups are the Duffy, Kell, Kidd, MNS, and P systems

3. * * 2 011 YT Cartwright 010 DI Diego 3 009 JK Kidd 6 008 FY Duffy 007
BLOOD GROUP SYSTEMS
CONVENTIONAL NAME 
  ISBT SYMBOL 
  ISBT NUMBER 
ANTIGENS  * 2
011 YT
   Cartwright
010 DI
   Diego 3
009 JK
   Kidd 6
008 FY
   Duffy
007 LE
   Lewis 21
006
KEL
   Kell 18
005 LU
   Lutheran 47
004 RH
   Rh 1
003 P1
   P 37
002
MNS
   MNSs 4
001
ABO
   ABO *

4. - - 2 5 10 7 1 9 3 026 JMH JMH 025 RAPH Raph 024 OK Ok 023 IN Indian
BLOOD GROUP SYSTEMS
  ANTIGENS 
  ISBT NUMBER 
  ISBT SYMBOL 
CONVENTIONAL NAME 
- - 2 5 10 7 1 9 3
026
JMH
   JMH
025
RAPH
   Raph
024 OK
   Ok
023 IN
   Indian
022 KN
   Knops
021
CROMER
   Cromer
020 GE
   Gerbich
019 XK
   Kx
018 H
   Hh
017
CH/RG
   Chido/Rogers
016 LW
   Landsteiner-Wiener
015 CO
   Colton
014 DO
   Dombrock
013 SC
   Scianna
012
XG0
   Xg

6. ABO blood group antigens present on red blood cells
and IgM antibodies present in the serum

7. Why do we have Anti-A or Anti-B Antibodies???
Viruses transmitted from the respiratory tracts of humans to other humans drag along various antigens including ABO blood group antigens.
Prime the newborn’s immune system.
Reduces transmissibility of viruses within a population.

8. Population Distribution of
Major Blood Groups
O Rh pos 38%
O Rh neg 7%
A Rh pos 34%
A Rh neg 6%
B Rh pos 9%
B Rh neg 2%
AB Rh pos 3%
AB Rh neg %

9. Red blood cell compatibility table  
AB+
AB- B+ B- A+ A- O+ O-
Donor
Recipient

10. Plasma compatibility table
Recipient
Donor O A B AB AB    A       B       O            

11. No naturally occurring antibodies Immune response requires
Other Blood Groups
No naturally occurring antibodies
Immune response requires
previous exposure
Weaker titers of univalent antibodies

12. Compatibility testing is done to avoid
Why do we care?
Compatibility testing is done to avoid
a hemolytic transfusion reaction
If the Host or Recipient recognizes
the donor RBC surface antigens as foreign,
the host will mount an immune response
to the donor RBC’s

13. The most significant is the
Major Blood Groups
Rhesus
47 Antigens make up the
Rhesus Blood Group
The most significant is the
D antigen

14. There is no naturally occurring Anti D Antibodies
Production of Anti D in the
RH negative recipient
requires previous exposure
to the D antigen
(in utero or by transfusion)

15. If red cells are administered to an ABO- or D-incompatible recipient,
the recipient will mount an
antibody response to the foreign
RBC surface antigens
IgM is polyvalent
and fixes complement

16. Intravascular Clumping of Donor RBC’s

17. Clumps and extruded RBC stroma result in organ dysfunction
and possible death
Incidence 1:38,000 – 1:70,000
Mortality 1:30

18. Intravascular hemolysis of donor RBC’s

19. Donor RBC’s coated with host antibodies Susceptible to attack by
Stiffer RBC membrane
Susceptible to attack by
splenic macrophages

20. intravascular clumping
But no
intravascular clumping

21. Bits of Donor RBC membrane lost traversing splenic sinusoids
(extravascular hemolysis)
Spherocytes
Decreased RBC survival
Delayed anemia
Priming for worse reaction

22. What is compatibility testing?
Also called pretransfusion testing
Purpose:
To select blood components that will not cause harm to the recipient and will have acceptable survival when transfused
If properly performed, compatibility tests will confirm ABO compatibility between the component and the recipient and will detect the most clinically significant unexpected antibodies

23. Patient Identification
Must confirm recipient’s ID from bracelet ON the patient
Full patient name and hospital number
Name of physician

24. COMPATIBILITY TESTING
Processing the specimen:
ABO Group determined (forward and reverse)
D typing determined
Antibody screen will be performed
ABO/Rh identical or compatible blood will be made available

25. Sample Identification
The sample should also have the full patient name, hospital number, and physician
Date and time of collection, phlebotomist’s initials
All of this should be on the request form and the sample

26. Specimen Tubes
Pink Top - EDTA
Red Top – no additives

27. Serological Testing 3 tests: ABO/Rh Antibody detection/identification
Crossmatch

28. ABO/Rh Typing In the ABO typing, the forward and reverse MUST match
In the Rh typing, the control must be negative
Both of these will indicate what type of blood should be given

29. ABO TYPING
Front or forward type using monoclonal anti-A and anti-B (commercial)
The sample is diluted to Hct 0.08, the commercial antibodies added & the test tube is centrifuged
The RBC’s are then examined for clumping (gross observation, gel suspension)

30. Anti A
Anti B
Anti A
Anti B A B
Anti A
Anti B
Anti A
Anti B AB O

31. ABO TYPING Back or reverse type with A and B cells
Commercially available A and B cells are added to two tubes of plasma
AB B A O A B A B A B A B

32. How do we know whether or not the host (or recipient) has antibodies to minor blood group antigens?
Add commercial RBC’s with known important minor antigens on their surface to host (or recipient) plasma and centrifuge. Then incubate at body temperature for minutes
Then add rabbit antiglobulin

33. Antibody screen
Also called the indirect Coombs test or the indirect antiglobulin test
The antibody screen will detect the presence of any unexpected antibodies in patient serum
If antibodies are detected, identification should be performed using panel cells (with an autocontrol) IS
37° (LISS)
AHG

34. If recipient antibodies have coated commercial RBC surfaces

35. Rabbit antiglobulin will bind to the
Antibodies and the RBC’s will clump

36. ANTIBODY SCREENING
Detection of unexpected clinically significant antibodies against the minor blood group system antigens
Positive in between 0 - 8% of samples depending on the population

37. Possibly significant minor blood groups2
011 YT
   Cartwright
010 DI
   Diego 3
009 JK
   Kidd 6
008 FY
   Duffy
007 LE
   Lewis 21
006
KEL
   Kell 18
005 LU
   Lutheran 47
004 RH
   Rh 1
003 P1
   P 37
002
MNS
   MNSs    *

38. SCREENING TEST RESULTS
A negative antibody screen allows blood to be dispensed using an immediate spin X-match or an electronic X-match, either of which confirms ABO compatibility
A positive antibody screen requires a full antiglobulin phase X-match

39. Crossmatching Purpose: Prevent transfusion reactions
Increase in vivo survival of red cells
Double checks for ABO errors
Another method of detecting antibodies

40. Crossmatches According to the AABB Standards:
The crossmatch “shall use methods that demonstrate ABO incompatibility and clinically significant antibodies to red cell antigens and shall include an antiglobulin phase”

41. Crossmatch No agglutination ~ compatible Agglutination ~ incompatible
Donor RBCs (washed)
Patient serum

42. The procedure
Donor cells are taken from segments that are attached to the unit itself
Segments are a sampling of the blood and eliminate having to open the actual unit

43. Crossmatch Procedure if antibodies are NOT detected:
Only immediate spin (IS) is performed using patient serum and donor blood suspension
This fulfills the AABB standard for ABO incompatibility
This is an INCOMPLETE CROSSMATCH
If antibodies ARE detected:
Antigen negative units found and X-matched
All phases are tested: IS, 37°, AHG
This is a COMPLETE CROSSMATCH

44. Crossmatches… Will Will Not Verify donor cell ABO compatibility
Detect most antibodies against donor cells
Will Not
Guarantee normal survival of RBCs
Prevent patient from developing an antibody
Detect all antibodies
Prevent delayed transfusion reactions

45. Approaches Requiring Less Than a Complete Crossmatch

46. Type and Screen
Determines the ABO-Rh of the patient and the presence of the most commonly found unexpected antibodies(elimination of the crossmatch ).

47. Type and Screen
If an emergency transfusion is required after type and screen alone, an immediate-phase crossmatch is performed.
Blood given in this manner is more than 99% effective in preventing incompatible transfusion reactions due to unexpected antibodies.

48. Is the Crossmatch Really Needed?
If the correct ABO and Rh blood type is given, the possibility of transfusing incompatible blood is less than 1 chance in 1000.
ABO-Rh typing alone results in a 99.8% chance of a compatible transfusion,
The addition of an antibody screen increases the safety to 99.94%, and
A crossmatch increases this to 99.95%.

49. Physician responsibility in ordering uncrossmatched blood
In an emergency (ER or OR), there may not be enough time to test the recipient’s sample
It is your judgment that the risk of the patient dying from from anemia is greater than the risk of transfusing the patient without pre-transfusion testing

50. What can be given in an emergency?
Type-Specific, Partially Crossmatched Blood
An ABO-Rh typing and an immediate-phase crossmatch
An abbreviated format
Macroscopic agglutination.
This takes 1 to 5 minutes

51. What can be given in an emergency?
Type-Specific, Uncrossmatched Blood
The ABO-Rh type
Most ABO type-specific transfusions are successful.
Caution should be used for patients who have previously received transfusions or have had pregnancies.

52. What can be given in an emergency?
Type O Rh-Negative (Universal Donor), Uncrossmatched Blood
Type O blood lacks the A and B antigens
Type O Rh-negative, uncrossmatched packed RBCs should be used in preference to type O Rh-negative whole blood.
More than two units of type O Rh-negative, uncrossmatched whole blood, the patient probably cannot be switched to his or her blood type .

53. Specific Recommended Protocol
Infuse crystalloids or colloids.
Draw a blood sample for typing and crossmatching.
If crossmatched blood is not ready to give, use type-specific or type O Rh-negative cells or type O Rh-positive cells for males or postmenopausal females without a history of transfusions.

54. Summary
The crossmatch “shall use methods that demonstrate ABO incompatibility and clinically significant antibodies to red cell antigens
If an emergency transfusion is required after type and screen alone, an immediate-phase crossmatch is performed before transfusion (an abbreviated format )
If crossmatched blood is not ready to give, use type-specific or type O Rh-negative cells