Gastrointestinal Pathogen Nucleic Acid Detection Panel Testing for Infectious Diarrhea

an effort to further investigate potential quality improvements in clinical management, use of antibiotics, and in-hospital infection transmission in children with acute diarrhea, Yoo et al. (2021) analyzed use of the BioFire ® FilmArray ® Gastrointestinal Panel (GI Panel) in a prospective study with a matched historical cohort. Participants in the prospective study included children younger than 19 years of age with new onset diarrhea. A 1:1 matched historical cohort of children diagnosed with acute gastroenteritis (AGE) during the 4 years prior to this investigation was analyzed as well. Children in the prospective cohort received stool testing using the GI Panel in addition to conventional methods. A total of 182 individuals with suspected infectious diarrhea were included in the prospective cohort. The median age was 3.8 years and 64.3% were male. Participants in this cohort were divided into two subgroups: community-onset diarrhea (85.7%) and hospital-onset diarrhea (14.3%). The GI Panel had a higher pathogen-positivity rate for community-onset diarrhea (58.3%) compared to both conventional studies (42.3%) and in the historical cohort (31.4%). Reporting time after admission averaged 25 hours for the GI Panel and 72 hours for the historical cohort. In addition, there was a reduction in antibiotic use in the prospective cohort compared to the historical cohort (35.3% vs 71.8%). In the prospective cohort, 126 different pathogens from 91 stool samples were identified by the GI Panel and in the historical cohort, 51 pathogens were identified from 49 stool samples. Of the 26 patients with hospital-onset diarrhea, a single pathogen was detected in 64.3% of the children and two or more pathogens were detected in 35.7%. Test results were used to make clinical decisions regarding isolation/precaution measures in-hospital. However, there were discrepancies between the results able to one or more standard conventional diagnostics in the had control groups with microbiological examination of performed using methods other than that although the FilmArray panel was positive in 39.7% of patients the carriage rates of must be that restricted ordering of molecular panels specific to those patients who might benefit from targeted treatment could provide clinical value by identifying the pathogen and treating appropriately, and future studies should on determining which of the identified pathogens in a test result are responsible for present and whether co-infections a Leli et al. (2020) evaluated and compared the diagnostic yield of the FilmArray gastrointestinal panel to that of routine stool culture for etiological diagnosis of infectious diarrhea. Stool samples (n=183) collected as part of routine care from March 2016 to March 2019 were included in this retrospective analysis. Samples were then cultured and tested by FilmArray and the following results from the comparison of diagnostic accuracy between culture and FilmArray with respect to Campylobacter, Salmonella, Shigella, Yersinia enterocolitica and Shiga-like toxin producing E. coli 0157 were reported: 100% (95% CI: 85-100%) sensitivity; 93.4% (95% CI: 87.9-96.6%) specificity; 74.3% (95% CI: 57.5-86.4%) positive predictive value; 100% (95% CI:96.7-100%) negative predictive value; 2.9% (95% CI: 1.6-5.1) positive likelihood ratio; zero negative likelihood ratio. The FilmArray gastrointestinal panel identified 34.5% more pathogens than traditional culture methods (p=0.001). The authors concluded that FilmArray identified a spectrum of pathogens and had good diagnostic performance when compared to standard culture for the diagnosis of infectious diarrhea. However, the study lacks clinical data and was performed in a single site in a community hospital setting, thus the pathogen detection rate cannot be completely generalized and positive results for c. difficile and viruses were not confirmed with alternative or reference methods. bacteria, 5 viruses and 2 parasites. The detection of enteropathogenic bacteria by multiplex PCR was enhanced by 25%. Enteroaggregative E.coli (n=32), enteropathogenic E. coli (n=26), enterotoxigenic E. coli (n=19), Salmonella enterica/enteroinvasive E. coli/Shigella (n=16 each), Cryptosporidium, sapovirus (n=11 each), Campylobaterjejuni, norovirus (n=10 each), rotavirus (n=9), Giardia (n=8) Shiga-toxin producing E. coli (n=4) in the controls. Patients with the GI panel had 0.18 abdomen and/or pelvic imaging studies per patient compared with 0.39 in the controls. The average length of time from stool culture collection to discharge was 3.4 days in the GI panel group versus 3.9 days in the controls. According to the authors, the GI panel improved patient care by rapidly identifying a broad range of pathogens which may not have otherwise been detected, reducing the need for other diagnostic tests, reducing unnecessary use of antibiotics, and leading to a reduction in hospital length of stay. This study suggests that the use of multiplex molecular panels result in an improvement in patient clinical outcomes in the setting of hospitalized patients with diarrhea.