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

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S38 Abstracts / Journal of Clinical Virology 82S (2016) S1–S142
Abstract no: 254
Presentation at ESCV 2016: Poster 34
Evaluation of the Aptima HIV-1 Quant Dx assay
on a wide panel of HIV-1 strains
Marie Gueudin ∗, Adeline Baron ,
Elodie Alessandri-Gradt , Véronique Lemée ,
Thomas Mourez , Julia Dina ,
Jean-Christophe Plantier
1 Laboratoire associé au Centre National de
Référence du VIH, CHU de Rouen–GRAM, Equipe
d’Accueil 2656, Faculté de Médecine-Pharmacie,
Université de Rouen Normandie, France
2 CHU de Caen, Department of Virology, Université
Caen Normandie, Medical School, Caen, France
Background: Plasma viral load (pVL) is usually used to monitor
HIV infected patients, to measure viral replication level and viro-
logical response to treatment. Recently, the new system Panther
(Hologic) and the Aptima HIV-1Quant Dx viral load assay have been
commercialized. This new generation of automaton gives faster
results due to random access loading of any sample at any time
and because all steps are performed in the instrument. The assay is
based on amplification of two targets (pol and LTR) using real-time
TMA. Before being widely adopted, the practicability of new com-
mercial systems must be evaluated as well as the performances of
their assays for detecting and quantifying thewide genetic diversity
of HIV-1 strains.
Methods: Aptima HIV-1 Quant Dx on Panther system (Hologic)
was compared to RealTime HIV-1 on m2000SP/m2000RT sys-
tem (Abbott Molecular); the Lower Limit Of Quantification was
30 cp/mL and 40 cp/mL for Aptima and RealTime respectively; both
assays were linear to 10million cp/mL.
90 HIV-1 group M selected plasma samples (15 subtype B, 75
non-B subtype) previously quantified with Real-Time, 201 plasma
prospectively collected, and 72 culture supernatants (49 HIV-1/M,
2 HIV-1/N, 20 HIV-1/O, 1 HIV-1/P) were compared. Data analy-
sis was performed using Bland- Altman graph and Passing Bablok
regression.
Results: Five of the 90 selected plasma were detected with
Aptima (pVL between 43 and 137 cp/ml with Real-Time). Twelve
(1 B and 11 non-B) of the 85 quantified samples by both assays
had higher pVL (+0.51 to +0.9 Log) with Aptima, with a mean of
differences of 0.22 Log.
112 of the 201 prospective plasma were undetectable, 17
detected and 16 quantified by both assays. 41 (20.4%) were detected
with Aptima and undetectable with Real-Time and 9 (4.5%) the
opposite. 3 (1.5%) were quantified with Aptima and detected with
Real-Time (pVL between 40 and 204 cp/ml) and 3 the opposite (pVL
between 45 and 53 cp/ml). All HIV-1 group M supernatants were
quantified; higher values were obtained with Aptima (mean of dif-
ferences = 0.35 Log) and 10 samples had differences between 0.51
and 0.98 Log in favor of Hologic and one (0.51 Log) in favor of Abbott.
Five group O supernatants were detected, but not quantified by
Aptima (pVL between 3.5 and 3.98 Log with Real-Time), two were
underquantified with Real-Time ( −0.53 and −2.88). The 2 groups
N and the group P gave higher values with Aptima (+1.29 to +1.72
Log).
Conclusion: Despite the major underquantification of 5 HIV-1
group O strains, performances of the Aptima assay on a wide panel
of HIV-1 strains are very good with globally a pVL mean higher as
well as more samples detected, than with the Real-Time assay.
Abstract no: 264
Presentation at ESCV 2016: Poster 35
CE-IVD validation of EBV ELITe MGB ® assay in
combination with ELITe InGeniusTM , an
innovative sample-to-result solution for in vitro
diagnostic
A. Bittoto ∗, S. Costa, M. Enrietto, S. Patanè,
F. Gorreta, A. Estampes, C. Olivo, G. Stefanuto,
W. Mahoney
ELITechGroup Molecular Diagnostics, United
Kingdom
Background: The “EBV ELITe MGB® Kit” is a qualitative and
quantitative nucleic acids amplification assay for the detection and
quantificationof Epstein-Barr humanherpetic Virus (EBV). The vali-
dation study was performed, on whole blood and plasma samples,
in combination with ELITe InGeniusTM, the first fully automated
sample-to-result solution introduced with a comprehensive quan-
titative transplant pathogen monitoring menu.
Material/methods: EBV ELITeMGB assay (ELITechGroupMolec-
ular Diagnostics) is a Real-Time PCR assay based on MGB
technology. ELITe InGeniusTM (ELITechGroup Molecular Diagnos-
tics) automatically performs nucleic acid extraction, PCR set-up,
Real-Time PCR amplification and results analysis. The evaluation
of the performances was designed according to European require-
ments for CE-IVD marking. The tests included: (1) verification
studies of the PCR performance to assess efficiency, linearity, preci-
sion, accuracy, repeatability, reproducibility and sensitivity for the
target and internal control, and (2) systemperformance verification
studies using four certified reference material panels (Qnostics Ltd.
and Acrometrix). The conversion factor to International Unit was
calculated using a panel of dilutions of calibrated reference mate-
rial (“1st WHO International Standard for Epstein-Barr Virus (EBV)
for Nucleic Acid Amplification Techniques”, NIBSC code 09/260,
UK). The clinical study included evaluation of diagnostic sensitivity
and specificity that were assessed by testing positive EBV clinical
samples and negative donor samples for each sample matrix.
Results: The PCR analytical sensitivity was verified at
10 copies/reaction. All certified references samples were correctly
detected and correctly quantified in international unit with a titer
within the expected value ±0.5 Log, except one educational sample
close to the lower limit of quantification of the test. The clinical sen-
sitivity was respectively 100% (30/30) and 100% (47/47) for whole
blood and plasma samples. The clinical specificity was respectively
90.6% (29/32) and 98.4% (60/61) for whole blood and plasma sam-
ples. When used in association to ELITe InGenius, EBV ELITe MGB
assay meets all the verification and validation criteria.
Conclusions: The results obtained support the CE-IVD marking
of EBV ELITe MGB kit in combination with the ELITe InGeniusTM
systemfor the detection and the quantification of EBVDNA inwhole
blood and plasma samples and for the diagnosis and monitoring of
EBV infections especially in transplant patients.