51
OCTOBER 16-18, 2011 • PORTLAND, OR
P15
Performance Evaluation of FMH QuikQuant
TM
,
a New Assay for Fetomaternal Hemorrhage
(FMH) on Multi-Parametric Flow Cytometers and
Hematology Analyzers
Irina Grigorieva, Teresa Casas, Susan Osier
Northside Hospital, Atlanta, GA, USA
Detection of fetal RBCs is used to estimate a degree
of FMH in suspected placental injury or Rhesus-D
incompatibility. The Kleihauer-Betke (K-B) assay for
FMH is a microscopy-based test built on differential
resistance of fetal hemoglobin to acid elution. Despite
the availability of more precise and reproducible
methods for measurement of FMH, K-B assay is
mostly used in clinical laboratories, performed on 24/7
basis. The Trillium Diagnostic FMH QuikQuant
TM
is an
innovative fow cytometric assay, based on binding
of fuorescently labeled mAB to fetal hemoglobin.
Elimination of repeated centrifugal washes makes
this assay simplifed and rapid relative to existing
methods. Bringing of Propidium Iodide fuorescent
dye for positive identifcation and exclusion of
nucleated cells increases the test precision. This
assay is proposed for use on multi-parametric fow
cytometers and on Cell-Dyn Sapphire Hematology
analyzer, which allows performing the test on 24/7
basis. We evaluated the performance of FMH
QuikQuant
TM
assay on fow cytometer FACSCanto
(BDBioSciences) and hematology analyzer Cell-Dyn
Sapphire (Abbott) in comparison with Caltag Fetal
Hemoglobin
TM
and K-B tests. Assessment of accuracy,
precision, linearity, assay stability and carryover was
performed on clinical specimens submitted for K-B
analysis and spiked samples. Replicate analysis
for fow cytometry method shows CV<5%, for
hematology method CV<10%. Linearity was shown
over the range of 0.05-6%. Correlation between
Caltag and QuikQuant assays on both platforms was
excellent (r
2
=0.9951 for fow cytometer, r
2
=0.9953
for hematology analyzer). We have concluded that
FMH QuikQuant
TM
assay demonstrates excellent
performance on both instruments – fow cytometer
and hematology analyzer.
POSTER ABSTRACTS