Identifying Enteropathogens in Children with Acute Gastroenteritis Presenting with Isolated Vomiting–Appetite Study

BACKGROUND: As diarrheal stool samples are the recommended specimen for testing in acute gastroenteritis (AGE), etiological investigations are rarely performed in children presenting with isolated vomiting. This study identifies enteropathogens in children with AGE presenting with isolated vomiting. METHODS: Children <18 years old with ≥3 episodes of vomiting/diarrhea in 24 hours and <7 days of symptoms were recruited in 2 pediatric emergency departments, a public health clinic and via Health Link, a provincial nurse advice phone line. Rectal swabs and stool samples were collected and tested using the Luminex xTAG GPP, an in-house 5-virus RT-qPCR panel and enteric bacterial culture. Vomiting and diarrhea data were collected at enrollment (day 0) and at day 14. RESULTS: Between Dec 9, 2014 and Apr 14, 2016, 2,184 children were enrolled and tested: 784 (36%) presented with isolated vomiting, 250 (11%) with isolated diarrhea (ID), 1,138 (52%) with both vomiting and diarrhea (V&D), 12 had missing data. The detection of enteropathogens was 56% when presenting with isolated vomiting, 55% with ID and 83% with V&D. Of the 784 children with isolated vomiting, 54% (n = 424) had one or more viruses: the most common was norovirus (NoV) (n = 244, 50%), followed by adenovirus (Adv) (91, 19%), rotavirus (Rota) (57, 12%), sapovirus (84, 17%) and astrovirus (10, 2%). Fifty-eight cases had >1 virus; co-infection with NoV and Adv was the most common (n = 23). Ten of these 424 patients also had enteric bacteria (2 Aeromonas, 2 ETEC, 2 Salmonella, 2 Yersinia, 1 Campylobacter, 1 E coli O157) and 8/9 (89%) of these patients reported development of diarrhea at day 14. In comparison, 212/383 (55%) of patients with virus only reported diarrhea at follow up. Enteric bacteria with no virus was detected in 11 patients (3 Aeromonas, 3 Salmonella, 3 STEC, 1 Campylobacter, 1 E coli O157) and 3/10 of these patients reported diarrhea. CONCLUSION: Over 50% of AGE presented with isolated vomiting had enteric virus identified in stool or rectal swabs, representing a significant pathogen-based disease burden not previously included in healthcare planning (e.g., Rota vaccine). NoV was the predominant agent followed by Adv and Rota. Finding enteric bacteria in these cases is novel and requires further study. DISCLOSURES: All authors: No reported disclosures.