Enteropathogens in pediatric gastroenteritis: comparison of routine diagnostic and molecular methods

Abstract Objectives Studies of acute gastroenteritis (AGE) are hampered by the lack of routine diagnostic methods with good sensitivity and specificity. Molecular methods are increasingly used for clinical purposes, but the clinical significance of a positive result remains a challenge. In this study we aimed to compare results of routine diagnostic methods and molecular methods in symptomatic children and asymptomatic controls. Methods Patients presenting to the pediatric emergency departments of two university hospitals in Brussels with AGE were recruited prospectively from 05/2015 to 10/2016; asymptomatic controls were recruited from the same hospitals. Stool analyses were performed for all participants for common pathogenic bacteria (culture), virus (immunochromatography) and parasites (microscopy). Stools were also analyzed with the Luminex Gastrointestinal Pathogen Panel, a multiplex-PCR for common enteropathogens. Results Stools from 178 patients and 165 controls were analyzed. An enteropathogen was detected in 62.4% (111/178) of cases when combining the 2 methods (56.2% -100/178- by Luminex, 42.7% -76/178- with routine methods) and 29.1% (48/165) of controls (24.2% -40/165- by Luminex and 10.3% -17/165- by routine methods). Some pathogens were detected more often with Luminex than with routine methods, like Salmonella (16.3% -29/178- with Luminex, 3.9% -7/178- with routine method, p Conclusions Molecular tools seem attractive methods, providing high positivity and a rapid turn-around time for the diagnosis of AGE. However, high rates of positivity in both cases and controls highlight the difficulty in interpreting results. Pathogens missed by Luminex but detected by culture methods raise more questions about the true clinical interest of the technique for our patients.