discrimination was performed using routine PCR of the National Reference Centre for respiratory viruses or Enteroviruses and Parechoviruses, Lyon,. France.
Evaluation of Liferiver respiratory viral kit in a hospitalized population TM
Maxime PICHON1,2,3, Alexandre GAYMARD 1,2,3, Marion JEANNOEL1,2,3, Caroline CHARRE1,4, Martine VALETTE1,2, Isabelle SCHUFFENECKER1,5, Florence MORFIN1,2,3, Bruno LINA1,2,3,5
Abstract n° 48
1. 2. 3. 4. 5.
Laboratoire de Virologie, Infectious Agents Institute, Hospices Civils de Lyon, Lyon, France National Reference Centre for Respiratory viruses, Infectious Agents Institute, Hospices Civils de Lyon, Lyon, France Lyon University, Virpath, CIRI, INSERM U1111, CNRS UMR5308, ENS Lyon, Université Claude Bernard Lyon 1, Lyon, France Centre International de Recherche en Infectiologie (CIRI) (Inserm U1111, CNRS UMR 5308), Lyon, France National Reference Centre for Enteroviruses and Parechoviruses, Infectious Agents Institute, Hospices Civils de Lyon, France
BACKGROUND
METHODS Enterovirus (EV) kit
Enterovirus (EV) (n=30)
Human respiratory infections are often associated with dramatic morbidity or mortality and mainly caused by viruses (1). Rapid and accurate diagnosis assays are essentials to identify as soon as possible the pathogens responsible, especially to obtain an early and appropriate therapeutic response (2). Several studies have demonstrated the advantages of multiplex PCR assays used routinely for the respiratory viral infection diagnosis (3).
Human Rhinovirus (HRV) kit Influenza A virus (H1N1) kit
Rhinovirus (RV) (n=30) Respiratory samples extracted
Influenza A virus (IFVA H1N1) (n=30) Influenza A virus (IFVA H3N2) (n=7)
Influenza virus A&B (IFV) kit Influenza B typing (IBV) kit Respiratory Syncytial virus (RSV) typing A&B kit
Influenza B virus (IFVB Yamagata) (n=15) Influenza B virus (IFVB Victoria) (n=15) Respiratory syncytial virus (RSV) (n=30) Respiratory MWS R-GENE®
Negative (n=10)
Figure 1. Pipeline of performance evaluation phase.
IFVB lineage determination and enterovirus/rhinovirus discrimination was performed using routine PCR of the National Reference Centre for respiratory viruses or Enteroviruses and Parechoviruses, Lyon, France. RSV was subtyped by sequencing. Discordances between Respiratory MWS R-Gene kit and tested kits were verified using a third method.
OBJECTIVES
TM Liferiver
Determination of kit’s performances (Se, Sp, PPV and NPV) TM Evaluation of Liferiver kit’s repeatability (CV)
Figure 2. Pipeline for the repeatability evaluation phase. Respiratory samples extracted
Viral load (Ct) determination MWS R-GENE®
Samples selection (1st, 2nd and 3rd quartile)
Ten replicates of each selected samples analyzed on the corresponding kit
For each kit, all analyses were performed during the same run. Standard deviation and coefficient of variation were determined during this phase. A questionnaire was also propose to each of the four experimenters for usability evaluation.
RESULTS ID RV EV RSV H1N1 IBVType IFVA-B
IFV
H1N1
IBV
RV
Viral target RV EV RSV-A RSV-B H1N1 Yam Vic IFVA IFVB
Med. viral load (Ct) Standard deviation CV (%) Med. viral load (Ct) Standard deviation CV (%) Med. viral load (Ct) Standard deviation CV (%)
Se 90,00% 86,67% 100,00% 100,00% 50,00% 100,00% 66,67% 86,67% 96,00%
Sp 100,00% 100,00% 48,00% 100,00% 100,00% 100,00% 100,00% 100,00% 100,00%
PPV 100,00% 100,00% 53,57% 100,00% 100,00% 100,00% 100,00% 100,00% 100,00%
1st Quartile 2nd Quartile 17.66 28.60 0.12 0.14 0.68 0.49 1st Quartile 2nd Quartile 25.16 36.60 0.16 0.85 0.62 2.34 1st Quartile 2nd Quartile 3rd Quartile 26.99 27.68 28.66 0.53 0.53 0.74 1.97 1.92 2.60
1st Quartile 2nd Quartile 3rd Quartile Med. viral load (Ct) 14.91 20.82 23.32 Standard deviation 1.16 0.60 0.86 CV (%) 7.75 2.89 3.68
NPV 76,92% 71,43% 100,00% 100,00% 40,00% 100,00% 83,33% 92,59% 96,15%
Table 1. Panel performance evaluation. Each ID (respiratory kit) was tested on target-positive samples (TPS) and target-negative samples (TNS). TN correspond to negative results using TNS and TP to positive results using TPS. FP correspond to positive results using TNS and FN to negative results using TPS. Se (sensitivity) correspond to TP/(FN+TP). Sp (specificity) correspond to TN/(TN+FN). PPV (positive predictive value) correspond to TP/(TP+FP). NPV (negative predictive value) correspond to TN/(TN+FN). Red, orange or green values correspond to results
