Evaluation of Luminex xTAG Gastrointestinal Pathogen Analyte-Specific Reagents for High-Throughput, Simultaneous Detection of Bacteria, Viruses, and Parasites of Clinical and Public Health Importance

Abstract

Acute diarrheal disease (ADD) can be caused by a range of pathogens, including bacteria, viruses, and parasites. Conventional diagnostic methods, such as culture, microscopy, biochemical assays, and enzyme-linked immunosorbent assays (ELISA), are laborious and time-consuming and lack sensitivity. Combined, the array of tests performed on a single specimen can increase the turnaround time (TAT) significantly. We validated a 19plex laboratory-developed gastrointestinal pathogen panel (GPP) using Luminex xTAG analyte-specific reagents (ASRs) to simultaneously screen directly in fecal specimens for diarrhea-causing pathogens, including bacteria (Campylobacter jejuni, Salmonella spp., Shigella spp., enterotoxigenic Escherichia coli [ETEC], Shiga toxin-producing E. coli [STEC], E. coli O157:H7, Vibrio cholerae, Yersinia enterocolitica, and toxigenic Clostridium difficile), parasites (Giardia lamblia, Cryptosporidium spp., and Entamoeba histolytica), and viruses (norovirus GI and GII, adenovirus 40/41, and rotavirus A). Performance characteristics of GPP ASRs were determined using 48 reference isolates and 254 clinical specimens. Stool specimens from individuals with diarrhea were tested for pathogens using conventional and molecular methods. Using the predictive methods as standards, the sensitivities of the GPP ASRs were 100% for adenovirus 40/41, norovirus, rotavirus A, Vibrio cholerae, Yersinia enterocolitica, Entamoeba histolytica, Cryptosporidium spp., and E. coli O157:H7; 95% for Giardia lamblia; 94% for ETEC and STEC; 93% for Shigella spp.; 92% for Salmonella spp.; 91% for C. difficile A/B toxins; and 90% for Campylobacter jejuni. The overall comparative performance of the GPP ASRs with conventional methods in clinical samples was 94.5% (range, 90% to 97%), with 99% (99.0% to 99.9%) specificity. Implementation of the GPP ASRs enables our public health laboratory to offer highly sensitive and specific screening and identification of the major ADD-causing pathogens.

Comparative Evaluation of Two Commercial Multiplex Panels for Detection of Gastrointestinal Pathogens by Use of Clinical Stool Specimens

“…For example, EAEC is not included on the Luminex assay. The association of pathogens with mixed infection is likely dependent on a variety of factors, including the geographic location and patient population (22,23). For example, a study performed in India showed that Vibrio cholerae and rotavirus were highly associated with coinfections (24).…”

Multicenter Evaluation of Clinical Diagnostic Methods for Detection and Isolation of Campylobacter spp. from Stool

“…Our study also provides real-world data in which informed considerations can be made on whether and how Campylobacter case definitions should be modified in the future. Highly sensitive and more specific nucleic acid amplification assays have more recently been approved by the FDA and may be preferable to stool antigen assays as alternatives to culture for detecting Campylobacter in stool (23)(24)(25)(26).…”

Site-Specific Clinical Evaluation of the Luminex xTAG Gastrointestinal Pathogen Panel for Detection of Infectious Gastroenteritis in Fecal Specimens

“…Recent studies have demonstrated that replacement of conventional methods with the xTAG GPP has improved sensitivity and TAT (12)(13)(14)(15). In an effort to address the workflow, cost benefits, and increased efficiencies of bringing GPP into our laboratories, we compared the costs per specimen, TATs, and hands-on staff times for GI pathogen diagnosis between conventional methods and GPP (Table 4).…”