Journal of Clinical Virology - Volume 82 - Supplement 1 - September 2016

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S24 Abstracts / Journal of Clinical Virology 82S (2016) S1–S142
compared against the overall consensus the reference qPCRmethod
and the dPCR assigned values.
The overall commercial consensus for the HSV1 sample was
3.8 Log10 copies/ml with qPCR 3.7 Log10 copies/ml and a dPCR result
4.1 Log10 copies/ml. The overall commercial consensus for the VZV
sample was 3.7 Log 10 copies/ml with qPCR 3.3 Log10 copies/ml and
a dPCR result 3.2 Log10 copies/ml.
Conclusions: A comparison of the results showthat dPCR results
aligned with the quantitative values determined using commer-
cial assays and the in-house qPCR assay despite an international
standard not being available. Digital PCR is advantageous allowing
quantitation without the need for a calibrated standard the data
presented here indicates that this is a useful method to calibrate
EQAmaterial allowing standardisation of the samples and allowing
comparison of results between laboratories.
Abstract no: 120
Presentation at ESCV 2016: Poster 5
Performance of the Aptima® HBV Quant assay
on the fully automated Panther® system
K. Gao ∗, J. Knight, T. Le, D. Do, A. James, T. Green,
A. Dickinson, M. Nguyen, L. Kangas, J. Tolentino,
A. Worlock, J. Linnen
Hologic Inc., USA
Background: The Aptima HBV Quant Assay is a quantitative
assay on the fully automated Panther system that recently received
CE-ICD approval. The assay uses real-time Transcription-Mediated
Amplification (TMA) technology and targets two regions of the
HBV genome to achieve high sensitivity and accurate quantitation.
This CE-IVD assay is intended for monitoring HBV DNA in plasma
and serum specimens as an aid in the management of patients
with chronic HBV infections undergoing antiviral therapy. Here we
describe validation studies of the assay.
Methods: The 95% Limit of Detection (LoD) of the assay was
determined by Probit analysis using dilutions of the 3rd HBV WHO
International Standard (NIBSC 10/264) and HBV positive specimens
(genotype A to H) inHBV negative human plasma and serum. Lower
Limit of Quantitation (LLOQ) was established for each genotype
by diluting clinical specimens and the 3 rd HBV WHO International
Standard in HBV negative human plasma and serum. Specificity
was determined using 292 fresh and 747 frozen specimens from
normal blood donors (521 plasma specimens and 518 serum spec-
imens). The linear range of the assay was established by dilution of
HBV DNA in plasma and serum at concentrations ranging from 0.86
to 9.26 log IU/mL. Linearity for genotype A to H was established by
dilution of linearized HBV DNA in buffer at concentrations ranging
from 1.44 to 8.44 log IU/mL. Precision was determined using a 28
member panel made by diluting HBV positive clinical specimens
or spiking HBV DNA into negative plasma and serum. A method
comparison was conducted against the Abbott RealTime HBV assay
using 614 clinical specimens from HBV infected patients.
Results: The 95% LoDusing the 3rdWHO standardwas 5.6 IU/mL
for plasma and 4.3 IU/mL for serum. The 95% LODacross 8 genotypes
was determined to be 6.4 IU/mL or lower for plasma and 7.3 IU/mL
or lower for serum. The LLOQ for the assay was 10 IU/mL. Speci-
ficity was 99.9% with 95% confidence intervals of 99.5–100% for
serum and plasma data combined. The assay demonstrated a linear
range of 1–9 log IU/mLwith good linearity across the range of quan-
titation for all genotypes. Precision was less than 0.23 log SD across
the range of the assay for both serum and plasma. Deming regres-
sion of quantitative results in 614 clinical specimens for Aptima
HBV Quant compared to Abbott RealTime HBV resulted in a slope
of 1.05, an intercept of −0.14, and an R2 of 0.99.
Conclusions: The Aptima HBV Quant assay on the fully auto-
mated Panther system is a highly sensitive and specific assay with
a broad dynamic range for quantitative detection of all HBV geno-
types. The assay results are highly correlated to those from Abbott
RealTime HBV assay. The performance of the Aptima HBV Quant
assay makes it an excellent candidate for sensitive monitoring of
HBV DNA in plasma and serum specimens.
Abstract no: 122
Presentation at ESCV 2016: Poster 6
Verification of the Argene ® real time PCR kits
on the new eMAGTM extraction platform
P. Marechal ∗, E. Billet-Hernandez ,
M. Bonabaud , F. Gelas , A. Derome ,
C. Barranger , A. Turc
1 bioMérieux, 138 Rue Louis Pasteur, Parc
Technologique Delta Sud, Verniolle, France
2 bioMérieux,Centre Christophe Mérieux, 5 rue des
Berges, Grenoble, France
NucliSENS® easyMAG® (bioMérieux) is one of the extraction
platforms currently claimed in the instructions of use of ARGENE®
real time PCR assays (bioMérieux). It’s successor bioMerieux’ new
extraction platform, named eMAGTM (*) , provides full automation of
sample extraction starting from primary tubes while keeping well
established NucliSENS® easyMAG® chemistry. Automation of the
extraction (primary sample tubemanagement, automated addition
of internal control, automated addition of silica, eluate transfer)
requires adaptation of the current NucliSENS ® easyMAG® extrac-
tion protocols to “eMAGTM extraction methods”.
Suitability of eMAGTM as nucleic acid extraction platform for
ARGENE ® real time PCR assays will be verified in performance stud-
ies demonstrating equivalency between easyMAG® and eMAGTM.
Flexibility of the laboratory workflow will be ensured by harmo-
nization of extraction methods available to the user on eMAGTM
in order to allow processing of several sample types in the same
extraction run.
The first part of the results from verification studies performed
in order to claim eMAGTM as suitable extraction platform for
different ARGENE® real time PCR assays will be presented. In par-
ticular, a focus will be made on the Legio pneumo/Cc r-gene® assay
(ARGENE® range, bioMérieux), which will be the first CE marked
kit to claim the eMAG nucleic acid extraction.
(*) Not yet commercialized.
Abstract no: 123
Presentation at ESCV 2016: Poster 7
External assay controls – How do you monitor
yours?
G. Prescott ∗, C. Morris, K. Doris, N. Almond
NIBSC, United Kingdom
For both serological and molecular diagnostic laboratories work
is performed within a quality system, typically ISO 15189. As a
result, laboratories are required to use and monitor an external run
control. These controls provide an independent control which is not