Download Comparison of Automated ABO/Rh and Antibody Screen Test

Comparison of Automated ABO/Rh and Antibody Screen Test
Performance for Maternal Samples and Blood Donors
Background: A regional
blood donor screening facility
performs ABO/Rh and
antibody screen testing for
cord blood products using
maternal samples on
automated equipment intended
for the screening of routine
blood donations. This study
was designed to compare “No
Typed Determined” (NTD)
rates on the automated pretransfusion analyzers and
antibody screen rates on solid
phase automation for maternal
and routine donors.
Method: An evaluation was
conducted comparing NTD and
antibody screen data for
maternal and routine blood
donations from June 2008 to
March 2009. The data was
generated from various
automated platforms and
gathered from the laboratory
information system. Initial
ABO/Rh testing was performed
with either the PK7300 or
PK7200 instruments. NTDs
were then resolved either on the
solid phase automation or
manual methods. Initial antibody
screen was performed by
automated solid phase. All initial
reactive (IR) antibody screen
samples were then tested by an
automated gel 3-cell method.
Results: The data demonstrate
that maternal samples have a far
greater prevalence of NTDs
(6.99%) and IR antibody screen
test results (2.15%) than routine
blood donors, NTDs (1.72%) and
IR (0.32%). It is important to note
that IR maternal samples repeat
at a higher percentage than
routine donor samples, 94.82%
and 70.31% respectively.
Descriptive statistics were
performed to compare routine
donor vs. maternal sample
performance for ABO/Rh and
antibody screen test results.
Routine donor sample NTD rates
are significantly better than
maternal samples, however
routine donors demonstrate a
higher solid phase antibody
screen false positive rate than
maternal samples.
Conclusion: The differences
between the maternal and
routine testing results are
statistically significant (pvalue < 0.05). The data
indicates that initial ABO/Rh
and antibody screen testing
for maternal samples are
more likely to require
additional testing as
compared to routine blood
donations.
ABORh
Volume
NTDs
%NTD
Antibody
Screen
Volume
Initial
Reactive
%IR
Repeat
Reactive
%RR
%RR to
IR
Maternal
Samples
48,916
3,418
6.99%
Maternal
Samples
51,102
1,101
2.15%
1,044
2.04%
94.82%
Routine
Donor
Samples
1,441,211
24,771
1.72%
Routine
Donor
Samples
1,457,727
4,594
0.32%
3,230
0.22%
70.31%
Poster ID: SP251
J. Jue
L. Vaughn
J. Dunn-William
G. Robertson
S. Caglioti
Blood Systems Laboratories,
Tempe AZ