217. Comparison of Three Commercial Multiplex Gastrointestinal Platforms for the Detection of Gastroenteritis Viruses
Session: Poster Abstract Session: Diagnostics: Enteric Infection
Thursday, October 27, 2016
Room: Poster Hall
Background:  Viruses are major etiological agents of childhood gastroenteritis. We evaluated the performance of three commercial multiplex platforms including FilmArray Gastrointestinal Panel (FGP), Luminex xTAG® Gastrointestinal Pathogen Panel (GPP) and TaqMan Array Card (TAC) (developed by E. Houpt, UVa) for the detection of five common causes of viral gastroenteritis.

Methods: 

A blinded panel of 300 archived stool samples was prepared containing rotavirus, norovirus, group F adenovirus, astrovirus, and sapovirus, or none of these viruses. Three laboratories tested this panel by TAC, FGP or GPP (which only detects rotavirus, norovirus and group F adenovirus). Samples positive by RT-q PCR and sequencing were considered true positives and samples testing negative by all methods were considered true negatives.

Results:

Of 207 true positive samples, FGP detected 199 (96.1%) and TAC 174 (84.0%) samples. GPP detected 100 (78.7%) of the 127 samples positive for the three viruses in its platform. Detection rates for rotavirus were highest (100%, 89.5% and 95.8%, for FGP, TAC and GPP, respectively) followed by astrovirus (97.4%, 92.3%, n/a), norovirus (87.8%, 87.8% and 78.0%), sapovirus (97.5%, 75.6%, n/a) and adenovirus (97.3%, 73.6% and 57.8%). The sensitivity of FGP, TAC and GPP was highest for rotavirus (100%, 89.6%, and 95.8%, respectively) and lowest for adenovirus (97.4%, 70.0% and 57.9%). The specificity of the FGP ranged from 99.6% (sapovirus) - 95.6% (rotavirus), whereas TAC specificity ranged from 100% (rotavirus) - 98.9% (astrovirus) and GPP specificity ranged from 100% (rotavirus/ adenovirus) - 99.6% (norovirus). For specimens containing low viral load (Ct values > 31), FGP detected 59/64 (92.1%) samples followed by TAC (35/64 (54.6%)) and GPP (14/37 (37.8%)).

Conclusion: Using a well-characterized stool panel, the FGP demonstrated the best analytical performance followed by TAC for the detection of 5 most important gastroenteritis viruses. Overall, multiplex molecular testing facilitates rapid and simultaneous detection of gastrointestinal pathogens. Further studies are required to understand the clinical relevance of each platform’s results including detection of co-infections, low viral loads, and other pathogens.

Preeti Chhabra, Ph.D.1, Nicole Gregoricus, MSPH1, Geoffrey Weinberg, MD, FIDSA, FPIDS2, Natasha Halasa, MD, MPH, FPIDS3, James D. Chappell, MD, PhD3, Ferdaus Hassan, PhD4, Rangaraj Selvarangan, PhD4, Leanne Ward, M.Sc1, Michael D. Bowen, PhD1, Daniel Payne, PhD, MSPH1 and Jan Vinjé, Ph.D.1, (1)Division of Viral Diseases, Centers for Disease Control and Prevention, Atlanta, GA, (2)Pediatrics, Univ. of Rochester Sch. of Med. and Dent., Rochester, NY, (3)Vanderbilt University Medical Center, Nashville, TN, (4)Children's Mercy Hospital and Clinics, Kansas City, MO

Disclosures:

P. Chhabra, None

N. Gregoricus, None

G. Weinberg, None

N. Halasa, Pfizer: Grant Investigator , Research grant
Biocryst: Grant Investigator , Research support
AstraZeneca: Grant Investigator , Research support
Baxter: Grant Investigator , Research grant

J. D. Chappell, None

F. Hassan, None

R. Selvarangan, None

L. Ward, None

M. D. Bowen, None

D. Payne, None

J. Vinjé, None

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