Etiologic and clinical characterization of community acquired gastroenteritis in adult patients in a Chilean emergency room by the FilmArray GI panel

Infectious diarrhea can be caused by a large number of microorganisms including bacteria virus and parasites. The clinical syndromic approach has been traditionally used to guide therapy. The aim of this study was to characterize the etiology of acute diarrhea by the FilmArray GI panel and to correlate it with its clinical presentation in an adult population presenting to the emergency room in a developing country. Material and Methods: Adult patients attending the ER due to acute diarrhea were selected. All patients included had a FilmArray GI panel performed and the clinical characteristics were recorded. Results: One hundred and ninety-nine patients were included. One hundred and eighteen (59.3%) were females. The mean age was 43 years old. Thirty three percent of the patients presented dysentery, 36.7% fever, 54.8% referred nauseas and 35.7% vomiting. Sixty three percent of the patients presented some degree of dehydration. In total, 221 microorganisms were detected of which 71.5% corresponded to bacteria (158/221), 19.9% to virus (44/221) and 8.6% to parasites (19/221). In 133 (67.0%) of 199 patients at least one microorganism was identified. Infections with more than one microorganism were detected in 27.1% of the patients. Polimicrobial infections were associated with a higher frequency of nausea (50.0% vs 32.0%, p 0.046), abdominal pain (87.0% vs 44.0%, p<0.0001) and travel history (20.0% vs 5.0%, p 0.0102). Bacterial infections occurred without a seasonal distribution with the exception of Salmonella sp whereas viral infections predominated during the autumn-winter months. Diarreicogenic E. coli were present in the context of a co-infection in more than 80.0% of the cases. Discussion: The use of multiplex panels has given us invaluable information regarding the epidemiology of acute diarrhea in adult. It highlighted the importance of polimicrobial infections and the frequency of diarreicogenic E. coli infections. Nevertheless, the lack of severity compared to monomicrobial infections and the usual association with other microorganisms in the latter make their clinical importance debatable.