1. Iranian Blood Transfusion Organization Immunohematology Reference Laboratory ABO&Rh(D) Discrepancies Between Forward and Reverse Grouping Solving Blood Bank Puzzles Case Studies
Mostafa Moghaddam MS, MT ( ASCP ) BB Head of Immunohematology Reference Laboratory

2. Based on serologic specificity of the causative IgG antibody ,HDFN is classified in to three categories:
Rh(D) hemolytic disease , due to anti-D alone or more rarely in combination with anti-C or anti-E . THIS IS THE MOST SEVERE TYPE and may result in fetal death. with anti-D, the second infant will be severely affected, and future pregnancies will usually result in stillbirth due to the increasing pathogenicity of the antibody.
“ Other HDFN” due to antibodies against other antigen in the Rh system, such as anti-c, anti-E, or anti-e , or the antigens in other blood group system, such as anti-K , anti-Fya and many others .Baby is usually mildly affected but sever HDFN has also been documented.
ABO HDFN ,due usually to anti-A,B in a group O woman , but rarely to anti-A or anti-B. THIS IS THE MOST COMMON FORM, BUT ALSO THE MILDEST.

3. Antibody Screening Test
Situation :
1- referred by F.A hospital
2- infant’s ABO blood group does not match with dad and mom’s ABO blood type
ABO&Rh(D)
Interpretation
Phenotype
Auto Control Test
Antibody Screening Test
Rh(D)
Reverse Grouping
Forward Grouping
Patient
Case E
DAT
Rh(D)Control
Anti-D
(IgM) B
Cell
A2 Cell
A1 Cell
Anti-
A,B
Anti-A A B+ 0
Negative 4+ NT
Mom O+
Dad A+ +
Infant
NT: Not Tested
Answer:
probably : blood specimens were switched & mislabeled
2- wrong infant was drawn
3 - infant was switched
4- need further investigation???!!!

4. Antibody Screening Test
Situation :
1- referred by M.K hospital
2- infant has a mismatched ABO type compare to her mom and dad’s ABO type
ABO&Rh(D)
Interpretation
Auto Control Test
Antibody Screening Test
Rh(D)
Reverse Grouping
Forward Grouping
Patient
Case
DAT
Rh(D)Control
Anti-D
(IgM) B
Cell
A2 Cell
A1 Cell
Anti- A,B
Anti- B
Anti-A
AB+ 0
Negative 4+ NT
Mom O+
Dad
Infant
NT: Not Tested
Answer:
probably :
infant was switched (human error) No
any history of blood transfusion ? No
mom is a CIS AB Maybe
any history of IVF ? No

5. Answer: probably : mom had a BMT in her childhood
Situation :
ABO&Rh(D)
Interpretation
Auto Control Test
Antibody Screening Test
Rh(D)
Reverse Grouping
Forward Grouping
Patient
Case
DAT
Rh(D)Control
Anti-D
(IgM) B
Cell
A2 Cell
A1 Cell
Anti- A,B
Anti- B
Anti-A
AB+ 0
Negative 4+ NT
Mom O+
Dad
Infant
NT: Not Tested
Answer:
probably :
mom had a BMT in her childhood

6. Antibody Screening Test
Situation :
referred by G hospital , 40years old mom Gravida : 3 para:3
Rh(D) mismatched with previous results
previously received RhIG
mom complains that she is Rh(D) negative and her husband is also Rh(D) negative !!!??
night shift reported mom’s Rh(D) as negative and her baby Rh(D) as positive but day shift reported mom as Rh(D)positive !!!
ABO&Rh(D)
Interpretation
Auto Control Test
Antibody Screening Test
Rh(D)
Reverse Grouping
Forward Grouping
Patient
Case
DAT
Rh(D)Control
Anti-D
(IgM/IgG) B
Cell
A2 Cell
A1 Cell
Anti-
A,B
Anti-A C
A negative
(night) 0
Negative 4+ NT
Mom
A positive (day) 3+
Dad
A positive
Infant
NT: Not Tested
Answer:
mom has a weak-Rh(D) reacting at AHG phase
Does she need to receive RhIG

8. Antibody Screening Test
Situation :
1- 28 years old female patient was referred by M.Y. hospital
2- blood bank was not able to determine patient ABO
ABO&Rh(D)
Interpretation
Auto Control Test
Antibody Screening Test
Rh(D)
Reverse Grouping
Forward Grouping
Incubation time
Case
DAT
Rh(D)Control
Anti-D
(IgM)
BCell
A2 Cell
A1 Cell
Anti-H
Anti-A,B
Anti-B
Anti-A1
Anti-A I
Unresolved positive
0 
Negative
Positive 4+ NT 3+ 1+ IS
A2B
C 15’°4
NT: Not Tested
IS: Immediate Spin
Your suggestions for ABO & Rh( D ) discrepancy?

9. Antibody Screening Test
Situation :
1- 28 years old female patient was referred by M.Y. hospital
2- blood bank was not able to determine patient ABO
ABO&Rh(D)
Interpretation
Auto Control Test
Antibody Screening Test
Rh(D)
Reverse Grouping
Forward Grouping
Incubation time
Case
DAT
Rh(D)Control
Anti-D
(IgM)
BCell
A2 Cell
A1 Cell
Anti-H
Anti-A,B
Anti-B
Anti-A1
Anti-A I
Unresolved positive
0 
Negative
Positive 4+ NT 3+ 1+ IS
A2B
C 15’°4
NT: Not Tested
IS: Immediate Spin
Answer:
Patient is a subgroup of A2B
Strong anti-A1 was observed in patient plasma
Transfusion recommendation?

10. Answer: 1- your thoughts
Situation :
1- referred by E bn S. hospital
2- infant’s ABO blood group does not match with mom and dad’s ABO blood type!!!
ABO&Rh(D)
Interpretation
Auto Control Test
Antibody Screening Test
Rh(D)
Reverse Grouping
Forward Grouping
Patient
Case
DAT
Rh(D)Control
Anti-D
(IgM) B
Cell A1
Anti-
A,B
Anti-A K
O positive 0
Negative 4+
Mom
A positive
Dad
AB positive NT 3+
Infant
NT: Not Tested
Answer:
1- your thoughts

11. Question: 1- Does an ABO discrepancy exist?
Situation :
A 27-year-old multiparous mom gave birth to a full- term girl
Baby's direct antiglobulin test was positive due to mom’s previous sensitization to anti-c
Blood bank further discovered an unexpected discrepancies in mom’s ABO blood grouping
ABO&Rh(D)
Interpretation
Auto Control Test
Antibody Screening Test
Rh(D)
Reverse Grouping
Forward Grouping
Patient
Case
DAT
Rh(D)Control
Anti-D
(IgM) B
Cell A1
Anti-
A,B
Anti-A J ? 0
Positive 4+ 2+
Mom
O positive
Negative
Dad NT
Infant
NT: Not Tested
Question:
1- Does an ABO discrepancy exist?