serological cases: what keeps us up at night stephanie goe, mt (aab-p) june 6, 2013
TRANSCRIPT
Serological Cases: What keeps us up at NightStephanie Goe, MT (AAB-P)
June 6, 2013
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Solving Problem Workups
• Unusual and rare antibodies present complex and challenging serological workups for the blood banker. This can be due to lack of experience, exposure and appropriate reagents.
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Dilemma.. “How do you know what you don’t know”
• How does one identify an antibody they have never seen ???
• Some antibodies react similarly. However, they can be completely benign, capable of producing a mild transfusion reaction or death.
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Goals
• The objectives of this case study are:
1. Presentation of a workup involving a clinically significant high incidence antibody Patient Information Serological techniques used for identification Challenges of finding compatible units
2. Compare and contrast a clinically significant and nonsignificant antibody
3. Discuss and show that “Antibodies don’t react by the book”
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Case Study
• Patient Information– 54 year old Caucasian female– Diagnosis: acute kidney injury, rhabdomylosis, multiple
traumas– Pregnancy and transfusion history unknown– Referring hospital transfused 6 rbcs as follows: * 2 rbcs on 2/26/13- DAT negative; no antibodies identified * 2 rbcs on 2/28/13 * 2 rbs on 03/15/2013- DAT negative; anti-c,-E, cold autoantibody
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What now? Specimen sent to IRL
• We rec’d both pre and post transfusion samples 10 days after patient initially presented to referring hospital
• All samples had substantial hemolysis ranging from 600 to 3000 mg % free hemoglobin
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Hmmm…How to proceed?
• Pretransfusion sample:* ABO/Rh: O Positive
* DAT: Negative with polyspecific AHG * Used to phenotype for common antigens *Patient phenotype:
C+,E-,c-,e+,M+,N+,S-,s+,K+,k+,Fy(a-b+),Jk(a+b+)
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Initial Testing
• Post Transfusion Specimen: * ABO/Rh: O Positive * DAT: w+ with polyspecific AHG & complement * Specimen grossly hemolyzed
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Initial Testing
Initial selected cell panel run in PEG which included a phenotypically similar cell.
IS results all 3+ except for the autocontrol
Reactions at IgG ranged from w+ to 1+
Panel tested in LISS yielded similar results
Initial Panels
LISS
PEGRh system Kell Duffy Kidd MNSs IS 3
7o
C
IgG
IgG
D C c E e K k Fya Fyb Jka Jkb M N S s
1 + + 0 0 + + + 0 + + 0 + + + + 3+ 2+ 1+ 3+
2 + + 0 0 + 0 + + 0 0 + 0 + + 0 3+ 2+ 1+ 3+
3 + + 0 0 + 0 + 0 + + 0 + 0 0 + 3+ 2+ 1+ 3+
4 + + 0 0 + + + 0 + + 0 0 + 0 + P.S. 3+ 2+ 1+ 3+
AC 0 0 0 0✓
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Now what?
• Similar strong IS reactivity with IgG carryover in panel cells
• Phenotypically similar cell reactive• Hx of cold autoantibody; however,
negative autocontrol! • Cold screen performed
Cold Screen Results
4C 37C
SC1 4+ 3+
SC2 4+ 3+
AC 0 0
I Neg 4+ 3+
I Neg 4+ 3+
Information Gained
• A cold reacting antibody present. However, not a cold autoantibody. Autocontrol is negative.
Panel with 0.01M DTT Treated Serum
LISSTest
Rh system Kell Duffy Kidd MNSs IS
37o
C
IgG
D C c E e K k Fya Fyb Jka Jkb M N S s
1 + + 0 0 + + + 0 + + 0 + + + + 0 0 1+
2 + + 0 0 + 0 + + 0 0 + 0 + + 0 0 0 1+
3 + + 0 0 + 0 + 0 + + 0 + 0 0 + 0 0 1+
4 + + 0 0 + + + 0 + + 0 0 + 0 + P.S. 0 0 1+
AC 0 0 0✓
Panel with Control Serum
LISSTest
Rh system Kell Duffy Kidd MNSs IS 37o
C
IgG
D C c E e K k Fya Fyb Jka Jkb M N S s
1 + + 0 0 + + + 0 + + 0 + + + + 3+ 2+ 2+
2 + + 0 0 + 0 + + 0 0 + 0 + + 0 3+ 2+ 2+
3 + + 0 0 + 0 + 0 + + 0 + 0 0 + 3+ 2+ 2+
4 + + 0 0 + + + 0 + + 0 0 + 0 + P.S. 3+ 2+ 2+
AC 0 0 0✓
Panel with 0.2M DTT Treated Cells
LISSTest
Rh system Kell Duffy Kidd MNSs IS 37o
C
IgG
D C c E e K k Fya Fyb Jka Jkb M N S s
1 + + 0 0 + + + 0 + + 0 + + + + 1+ 1+ 1+
2 + + 0 0 + 0 + + 0 0 + 0 + + 0 1+ 1+ w+
3 + + 0 0 + 0 + 0 + + 0 + 0 0 + 1+ 1+ 1+
4 + + 0 0 + + + 0 + + 0 0 + 0 + P.S. 1+ 1+ 1+
AC 0 0 0✓
Recap
• IgM reactivity abolished with 0.01M DTT treated serum (IgG component still present)
• Diminished reactivity with 0.2M DTT treated cells • Reactive phenotypically similar cell
• Negative autocontrol ………Possible high??
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What are Some Candidates?
• Patient is Caucasian• IS reactions• Diminished reactivity with 0.2M DTT
treated cells
Possible PP1Pk, I, H, Vel ?
Panel Reflecting R2R2 2x PEG Adsorbed Sera Results
Rh system Kell Duffy Kidd MNSs R2R2
D C c E e K k Fya Fyb Jka Jkb M N S s
1 + + 0 0 + + + 0 + + 0 + + + + 0✓
2 + + 0 0 + 0 + + 0 0 + 0 + + 0 0✓
3 + + 0 0 + 0 + 0 + + 0 + 0 0 + 0✓
4 + + 0 0 + + + 0 + + 0 0 + 0 + P.S. 0✓
Differential Cells
R1R1
P1+; M+N-S+s-;K-; Fy(a+b-); Jk(a-b+)
R2R2
P1+; M-N+S-s+;K-; Fy(a-b+); Jk(a+b+)
rrP1-; M+N+S-s+;K-; Fy(a-b+); Jk(a+b-)
Additional Phenotyping
• Patient typed with the following antisera:Anti-H -P1 -I -Vel
Pos Pos Pos Neg
Antigen Negative Cells Tested
LISS
PEG
Rh system Kell Duffy Kidd MNSs IS
37o
C
IgG
IgG
D C c E e K k Fya
Fyb
Jka Jkb M N S s Vel
1 + + 0 0 + + + + + + 0 + + + + 0 0 0 0 0✓
2 + + 0 0 + 0 + + 0 0 + 0 + + 0 0 0 0 0 0✓
Prewarm Panel
Prewarm
Rh system Kell Duffy Kidd MNSs
IgG
D C c E e K k Fya Fyb Jka Jkb M N S s
1 + + 0 0 + + + + + + 0 + + + + 2+
2 + + 0 0 + 0 + + 0 0 + 0 + + 0 2+
3 + + 0 0 + 0 + 0 + + 0 + 0 0 + 2+
4 + + 0 0 + + + 0 + + 0 0 + 0 + P.S. 2+
AC 0✓
REStTM Adsorbed Sera 1X
LISS
Rh system Kell Duffy Kidd MNSs IS 37o
C
IgG
D C c E e K k Fya Fyb Jka Jkb M N S s
1 + + 0 0 + + + + + + 0 + + + + 3+ 3+ 3+
2 + + 0 0 + 0 + + 0 0 + 0 + + 0 3+ 3+ 3+
3 + + 0 0 + 0 + 0 + + 0 + 0 0 + 3+ 3+ 3+
4 + + 0 0 + + + 0 + + 0 0 + 0 + P.S. 3+ 3+ 3+
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Anti-Vel
• Antibody to the high incidence antigen that is present
in > 99 % of the population• Can be both IgM and IgG in nature• IgM complement binding anti-Vel can sometimes
present as hemolysins • Anti-Vel can cause severe hemolytic transfusion
reactions• Anecdotal reports of successful Vel+ transfusions.
Not recommended.
A Tale of Two Antibodies…..
• “It was the very best of times. It was the very worst of times” -Charles Dickens
• Let’s compare a similarly reacting nonsignificant antibody to our anti-Vel
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Ex. Nonsignifcant anti-I and cold autoantibody
PEG
Kell Duffy Kidd MNSs IS
IgG
D C c E e K k Fya Fyb Jka Jkb M N S s 3+ 1+1 0 0 + 0 + 0 + 0 + + 0 + + 0 + 3+ 1+2 0 0 + 0 + 0 + 0 0 0 + 0 + 0 + 3+ 1+3 + 0 + 0 + 0 + 0 0 + 0 0 + 0 + 3+ 1+4 0 0 + 0 + 0 + 0 0 + 0 0 + 0 + I- 3+ 0✓
AC 1+ 0✓
Comparisons
Anti-Vel
• IS reactivity• IgM carryover• Negative autocontrol
Anti-I and cold autoantibody• IS Reactivity• IgM carryover• Negative autocontrol at IgG
Contrast
Anti-Vel
• Cord cells reactivity not diminished
• Reactivity not diminished by prewarm technique
Anti-I and Cold autoantibody• Cord cell reactivity
diminished• Reactions eliminated by
prewarm technique
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Cautionary Tale
• Exercise caution using the prewarm technique as significant alloantibodies can be eliminated.
• If you have IS reactions and a negative autocontrol, proceed with caution
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…But it’s Not What the Textbook Said
• Not all antibodies behave in textbook fashion. Our anti-Vel behaved differently in several ways:
• (1) Cord cells did not react weaker• (2) REStTM did not adsorb out the
anti-Vel
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..and Our Patient?
• We believe our patient exhibited an anamnestic response to the initial transfusion and was undergoing a transfusion reaction.
• We initiated an ARDP search and imported 2 rbcs.
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Works Cited
• Lomas-Francis C, Reid M, The Blood Antigens Fact Book 2nd ed. New York City, New York: New York Blood Center; 2004
• Anstee J, Issitt Peter, Applied Blood Group Serology 4th ed. Durham, North Carolina: Montgomery Scientific Publications; 1998