ABO Discrepancies Disclosure Objectives Importance Recognition ...

4/12/2011
Case Study #3: Patient History
Anti-A Anti-B Anti-A,B Anti-D
D
Control
A 1 cells A 2 cells B cells
• 45 year old man
• Diagnosis: Recurrent GI bleed
• Medications: None
• Transfusion History: 10 in past year; none in last
3 months
• Lab: Hemoglobin: 9.2 g/dL
Patient 4+ w+ 4+ 4+ 0 w+ 2+ 3+
Screening
Cells
DAT
IS
PEG/IAT
I 1+ 0
II 1+ 0
III 1+ 0
Anti-IgG
Anti-
C3dC3b
Saline
Control
Patient 0 0 0
What is the problem?
Forward and Reverse typing
issue
Investigation
Patient age: 45 years old
Diagnosis: Recurrent GI bleed
Medications: None
Resolution:
Additional antibody in front
type and reverse type
Additional antibody in the front and reverse type resolution
Forward type:
Wash red cells extensively and repeat testing
Removes proteins
Reverse type
Saline replacement technique;
Patient cells and serum combined and centrifuged
Allows for antigen/antibody reaction (if present)
Remove serum and replace with equal volume of saline
Mix, centrifuge, and reexamine for agglutination
Both macroscopically and microscopically
Front Type:
Anti-A Anti-B Anti-A,B
Patient 4+ w+ 4+
Patient Cells
washed X6
with Saline
4+ 0 4+
Reverse Type:
A 1 cells A 2 cells B cells
Patient w+ 2+ 3+
Saline
Replacement 0 1+ 3+
Screening IS
PEG/IAT
Cells
(saline
replacement)
I w+ 0
II 0 0
III w+ 0
Forward type resolved:
Patient forward type: A
Reverse type NOT resolved:
cold alloantibody??
Anti-M identified at IS
53
54
Reverse grouping cells need to be antigen typed for the M antigen.
A 1 cells
(original source)
A 2 cells
(original source)
B cells
(original source)
A 2 cells
(second source)
B cells
(second source)
Anti-M
0
2+
1+
0
0
•The original source of A 2 and B
cells are M antigen positive. Since
the patient has anti-M identified at
IS, this antigen is interfering with
the reverse grouping (causing a
discrepancy).
•A second source of A 2 and B cells
were located that are M antigen
negative. These cells will be used
to perform reverse grouping on this
patient.
Anti-A Anti-B Anti-A,B Anti-D
D
Control
A 1 cells A 2 cells B cells
Patient 4+ w+ 4+ 4+ 0 w+ 2+ 3+
Washed X6 with normal saline
(second source,
M antigen negative)
Saline
replacement
4+ 0 4+ 0 0 3+
9