Rectal swabs and stool samples identified an enteropathogen in more than half of children who presented with isolated vomiting, and nearly one-third of the pathogens were noroviruses, according to the results of a study published in Clinical Infectious Diseases. Diagnostic tools for acute gastroenteritis in children are geared toward the presence of diarrhea, so data are lacking on causative agents contributing to acute gastroenteritis with isolated vomiting.
Investigators analyzed data from the Alberta Provincial Pediatric EnTeric Infection TEam (APPETITE) study of children 18 years of age and younger who presented to the emergency department (ED) with presumed acute gastroenteritis between December 2014 and August 2018. Patients with 3 or more episodes of vomiting and/or diarrhea in a 24-hour period and who experienced less than 7 days of symptoms were included in the study. Asymptomatic children who presented to the ED for noninfectious reasons were also recruited as a control group. Study personnel blinded to clinical information collected 2 rectal swabs and a stool sample from the group with acute gastroenteritis; only stool specimens were obtained from the control group. Study personnel contacted caregivers 14 days later to complete a survey on patient symptoms and any additional clinical care received.
Of the 2695 participants with acute gastroenteritis, 295 (10%) had isolated diarrhea, 1321 (49%) had vomiting and diarrhea, and 1079 (40%) had isolated vomiting. The median age of children with isolated vomiting was 2 years (IQR 0.9-4.6 years), which was older than children with isolated diarrhea and both vomiting and diarrhea (P <.001). Children with isolated vomiting were least likely to submit stool specimens (64.9%), and children with isolated diarrhea were most likely to submit stool specimens (75.3%).
An enteropathogen was detected most often in patients with vomiting and diarrhea (80.8%), and the most common pathogen detected was a virus (76.5%). There was no significant difference in enteropathogen detection between patients with isolated diarrhea and isolated vomiting (95% CI, -3.4 to 9.3). A pathogen was identified in 129 of 652 (19.8%) stool specimens in the control group; non-enteric adenovirus was the pathogen most frequently identified.
A virus was implicated in 51.7% of the children with isolated, most commonly a norovirus (29.8%). Adenovirus was the most common pathogen found in children with isolated diarrhea (22.4%). Children with isolated vomiting were least likely to have a bacterial pathogen (5.7%), and 50% of bacterial pathogens in these children aged 2 years and older were Clostridioides difficile. Bacterial pathogens were most commonly found in children with isolated diarrhea (16.9%).
Of 942 patients who initially presented with isolated vomiting and completed the 14-day follow-up, 44.5% eventually developed diarrhea. At the 14-day follow-up, patients with isolated vomiting at were least likely to remain positive for an enteropathogen (249/523, 47.6%) compared with 77.3% (1369/1770) of children with vomiting and diarrhea at 14 days following presentation to the ED.
Children with isolated vomiting were most likely to have a non-gastrointestinal chronic medical illness (11.6%) and least likely to have a fever prior to the ED visit (35.5%). Children with isolated vomiting were also more likely to undergo radiographic examination, ultrasound examination, and urine tests. Patients with isolated vomiting were most likely to have alternate etiologies for their symptoms, with urinary tract infection reported as the most common alternate diagnosis (66/98 [67.4%]).
Limitations of the study included not testing all children thoroughly for alternate diagnoses, and data were abstracted from discharge diagnoses from the treating ED physician. Some children may have had a different explanation for their illness that occurred after the 14-day follow-up period.
“Rectal swabs and access to sensitive rapid molecular tests are valuable additions to the diagnostic approach to children with isolated vomiting,” the study authors wrote, adding that these diagnostic tools can “lead to earlier identification of children’s bacterial enteric pathogens, while reducing the frequency of misdiagnoses and use of other tests and procedures.”
Freedman SB, Xie J, Lee BE, et al. Microbial etiologies and clinical characteristics of children seeking emergency department care due to vomiting in the absence of diarrhea. Clin Infect Dis. Published online May 16, 2021. doi:10.1093/cid/ciab451