Finding the Phenotype of a Recently Transfused Warm ... · August 18, 2017 [email protected] ....
Transcript of Finding the Phenotype of a Recently Transfused Warm ... · August 18, 2017 [email protected] ....
Finding the Phenotype of a
Recently Transfused Warm
Autoantibody Patient
Kathy Evans MS, MT(ASCP)BB
Blood Bank Master Tech at UKHC Good Samaritan Hospital
August 18, 2017
Background
• Indiana Blood Center IRL, Indianapolis, IN
• UK HealthCare Good Samaritan Hospital, Lexington, KY
Objectives
• Identify the key differences between a typical patient and
a patient that presents with a warm autoantibody in the
Blood Bank.
• Describe the additional testing required to complete a
warm autoantibody.
• Discuss the practical use for molecular testing for recently
transfused patients with a warm autoantibody.
Single Alloantibody
BLOOD TYPE
Anti-A Anti-B Anti-A,B Anti-D Ctrl A1 C B C Interp
4+ 0 4+ 4+ 0 0 4+ A positive
IAT SCREEN
Cell Antigens Gel
D C E c e K k Fya Fyb Jka Jkb M N S s
I + + 0 0 + 0 + + + 0 + + + 0 + 0
II + 0 + + 0 0 + + 0 + 0 0 + 0 + 3+
III 0 0 0 + + + + 0 + + + + 0 + 0 0
INTERPRETATION: IAT Positive
Case Patient: Atypical, Andy
IAT PANEL
Cell Antigens Testing
D C E c e K k Fya Fyb Jka Jkb M N S s Gel
1 + + 0 0 + 0 + 0 + + 0 + + 0 + 0
2 + + 0 0 + 0 + + + + 0 0 + 0 + 0
3 + 0 + + 0 0 + + + + + + 0 0 + 4+
4 + 0 0 + + 0 + 0 0 + 0 + + 0 + 0
5 0 + 0 + + 0 + 0 + + 0 + + 0 + 0
6 0 0 + + + 0 + 0 0 + 0 + + 0 + 3+
7 0 0 0 + + + + 0 + 0 + + 0 + + 0
8 0 0 0 + + 0 + + 0 + + + + 0 + 0
9 0 0 0 + + 0 + + 0 + + + + 0 + 0
10 0 0 0 + + 0 + + 0 0 + 0 + + 0 0
AC 0
INTERPRETATION: Anti-E
Additional testing
• Panel with Autocontrol
• Direct Antiglobulin Test
• Elution
• IgG removal
• Cell separation*
• Extended red cell phenotype
• Auto-adsorption or Allo-adsorption*
• Auto-checks
Looks like a Warm
Autoantibody
Case Patient: Transfused, Teddy
BLOOD TYPE
Anti-A Anti-B Anti-A,B Anti-D Ctrl A1 C B C Interp
4+mf 0 4+mf 4+ 0 0 4+ A positive
IAT SCREEN
Cell Antigens Gel
D C E c e K k Fya Fyb Jka Jkb M N S s
I + + 0 0 + 0 + + + 0 + + + 0 + 4+
II + 0 + + 0 0 + + 0 + 0 0 + 0 + 4+
III 0 0 0 + + + + 0 + + + + 0 + 0 4+
INTERPRETATION: IAT Positive
DAT SCREEN
Poly IgG IgG IgG Ctrl C3 C3
ctrl
Interp
3+mf 3+mf 0 0 0 positive
Rh Phenotype
C E c e Ctrl
2+mf 1+mf 4+ 4+ 0
Looks like a Warm
Autoantibody
Case Patient: Transfused, Teddy
IAT PANEL
Cell Antigens Testing
D C E c e K k Fya Fyb Jka Jkb M N S s Gel PEG LISS
1 + + 0 0 + 0 + 0 + + 0 + + 0 + 4+ 4+ 3+
2 + + 0 0 + 0 + + + + 0 0 + 0 + 4+ 4+ 3+
3 + 0 + + 0 0 + + + + + + 0 0 + 4+ 4+ 3+
4 + 0 0 + + 0 + 0 0 + 0 + + 0 + 4+ 4+ 3+
5 0 + 0 + + 0 + 0 + + 0 + + 0 + 4+ 4+ 3+
6 0 0 + + + 0 + 0 0 + 0 + + 0 + 4+ 4+ 3+
7 0 0 0 + + + + 0 + 0 + + 0 + + 4+ 4+ 3+
8 0 0 0 + + 0 + + 0 + + + + 0 + 4+ 4+ 3+
9 0 0 0 + + 0 + + 0 + + + + 0 + 4+ 4+ 3+
10 0 0 0 + + 0 + + 0 0 + 0 + + 0 4+ 4+ 3+
AC 4+ 4+ 3+
Elution
Patient’s Red Cells Eluate
IgG IgG
IgG
IgG IgG
Case Patient: Transfused, Teddy
Acid wash
ELUTION
Cell Antigens Testing
D C E c e K k Fya Fyb Jka Jkb M N S s ELU LW
SC I + + 0 0 + 0 + + + 0 + 0 + + 0 4+ 0
SC2 + 0 + + 0 + + 0 + + 0 0 + 0 + 4+ 0
SC3 0 0 0 + + 0 + + 0 + + + 0 0 + 4+ 0
IgG Coated Red Cells
• When your red cells are coated with IgG
• EGA (EDTA glycine acid)
• CDP (Choloroquin diphosphate)
Y Ls
IgG
IgG
Ls Ls
Ls
Ls Ls
Patient coated red cells Patient treated red cells IgG removed
Recently transfused
• Why is “recently transfused” important to know?
• Cell Separation Techniques:
Retic harvest
Hypotonic cell wash
Impact of Cell Separation
on Phenotype testing:
6mm
Rh Phenotype
C E c e Ctrl
2+mf 1+mf 4+ 4+ 0
Rh Phenotype
C E c e Ctrl
0 0 4+ 4+ 0
Extended phenotype testing
Case Patient: Transfused, Teddy
IgG REMOVAL
Patient 0
Control Donor 0
BLOOD TYPE
Anti-A Anti-B Anti-A,B Anti-D Ctrl A1 C B C Interp
4+ 0 4+ 4+ 0 0 4+ A positive
DAT SCREEN
Poly IgG IgG IgG Ctrl C3 C3
ctrl
Interp
3+ 3+ 0 0 0 positive
Rh Phenotype
C E c e Ctrl
0 0 4+ 4+ 0
Extended Phenotype
K k Fya Fyb Jka Jkb S s M N Lea Leb
0 NA 0 0 0 3+ 0 4+ NA NA NA NA
Auto-Adsorption
• ZZAP treated patient cells
• Patient’s plasma
• Depending on strength of reactions, could be up to 4 serial
adsorptions (45 minutes each)
Patient
Patient
A B
C
Bound and unbound IgG
Alloantibody if present
Allo-Adsorption
• ZZAP treated known cells (R1R1, R2R2, rr)
• Patient’s plasma
• Depending on strength of reactions, could be up to 4 serial
adsorptions each (45 minutes each)
Patient
rr
R2R2
R1R1
A C B
Auto-IgG and Allo-IgG
Transfused WAA Allo-adsorption
ALLO-ADSORPTION PANEL (x4)
Cell Antigens Testing
D C E c e K k Fya Fyb Jka Jkb M N S s R1
LISS
R2
LISS
rr
LISS
1 + + 0 0 + 0 + 0 + + 0 + + 0 + 0 0 0
2 + + 0 0 + 0 + + + + 0 0 + 0 + 0 0 0
3 + 0 + + 0 0 + + + + + + 0 0 + 0 0 0
4 + 0 0 + + 0 + 0 0 + 0 + + 0 + 0 0 0
5 0 + 0 + + 0 + 0 + + 0 + + 0 + 0 0 0
6 0 0 + + + 0 + 0 0 + 0 + + 0 + 0 0 0
7 0 0 0 + + + + 0 + 0 + + 0 + + 3+ 3+ 3+
8 0 0 0 + + 0 + + 0 + + + + 0 + 0 0 0
9 0 0 0 + + 0 + + 0 + + + + 0 + 0 0 0
10 0 0 0 + + 0 + + 0 0 + 0 + + 0 3+ 3+ 3+
PT* 0 0 0
INTERPRETATION: Warm Autoantibody
Case Patient: Transfused, Teddy
Auto-Checks
Case Patient: Transfused, Teddy
IgG IgG
Treated cells
AUTO CHECKS (after cell separation)
DAT IgG PEG-AHG LISS-AHG Gel Eluate
0 3+ 3+ 4+ 3+
Transfused WAA Common
Issues
• Quantity
Not a Sufficient Quantity of patient red
cells
• Quality
-Ability to provide red cell separation
based on when the last transfusion
occurred
-The patient is not producing retics
-IgG coating red cells too heavy to be
removed
Advantages to Molecular
• Can provide extended antigen typing otherwise difficult to conclude with serological testing
• Not effected by recent transfusions
• Future alloantibodies generally limited to absent antigens
• Provide information about “self-antibodies”
• Serologic typing discrepancy or ambiguity
Patient Population
• Anemias (sickle cell, thalassemia), autoantibodies, anti-
CD38, complex multiple unidentified or high frequency
antigen alloantibodies, antibodies with no or little typing
sera available such as Do, Js, Kp, V
Conclusions:
• The key differences between a typical patient and a patient that presents with a warm autoantibody in the Blood Bank are; panreactivity seen in the antibody screen and panel, a positive autocontrol, and a positive DAT.
• Additional testing required to complete a warm autoantibody include; direct antiglobulin testing, elution, IgG removal, extended phenyotyping, cell separation, and adsorptions.
• Antigen typing by Molecular method on recently transfused patients with a warm autoantibody can provide conclusive extended antigen typing dependent of transfusion status and bound IgG on the patient’s red cells. This will aid in future transfusions for these patients.
References
• Technical Manual AABB Bethesda Maryland
• The Blood Group Antigen Facts Book Marion E Reid &
Christine Lomas-Francis
• Modern Blood Banking and Transfusion Practices Denise
M Harmening
• Beadchip Molecular Immunohematology JoAnne M
Moulds