Clinical Assessment for Viral Gastroenteritis

Key Historical Features That Point to Viral Gastroenteritis

The Centers for Disease Control and Prevention recommends asking about sudden onset of symptoms, presence of diarrhea within 24 hours, low-grade fever, absence of bilious or bloody vomiting, and whether other family members or classmates are ill to determine if vomiting in a 9-year-old is viral gastroenteritis 1, 2
Sudden onset of vomiting is characteristic, typically beginning abruptly rather than gradually worsening 1
Incubation period of 24-48 hours for Norwalk-like viruses or 1-3 days for rotavirus 1, 3
Duration of illness typically 12-60 hours for Norwalk virus or 3-8 days for rotavirus, with complete resolution expected within days 1, 4
Diarrhea developing 24-48 hours after vomiting starts, which is watery and never bloody 1, 3, 2
Low-grade fever, if present at all, with high fever >39°C being less common and occurring in only one-third of viral cases 3
Nausea and abdominal cramping are common symptoms, occurring in 79% and 71% of viral outbreaks respectively 1
Headache, myalgias, and sometimes sore throat are also common symptoms, occurring in 50%, 26%, and 18% of cases respectively 1

The American Academy of Pediatrics suggests asking if other children at school or family members are sick with similar symptoms, as viral gastroenteritis often appears in epidemics or clusters 1, 2
Recent exposure to day care centers or group settings increases likelihood of viral transmission 3
Time of year, with rotavirus peaking November through May and Norwalk-like viruses occurring year-round, can be a clue to the diagnosis 3

The American College of Radiology recommends assessing skin turgor, mucous membrane moisture, mental status, capillary refill, and vital signs to categorize dehydration as mild, moderate, or severe 2, 6
Vomiting in viral gastroenteritis is typically brief, lasting <24 hours in most children 3

The Infectious Diseases Society of America states that stool microbiological tests are not routinely needed when viral gastroenteritis is the likely diagnosis based on clinical presentation and mild illness, but mild leukocytosis can occur with viral gastroenteritis and does not necessarily indicate bacterial infection 2
Bloody diarrhea or white blood cells on stool examination warrant stool cultures to rule out bacterial pathogens 7, 6

The Journal of the American College of Radiology advises against assuming viral gastroenteritis without considering bilious vomiting, which requires immediate imaging to rule out malrotation with volvulus 5
The American Academy of Pediatrics recommends beginning oral rehydration solution immediately and not delaying rehydration while pursuing diagnostic testing if viral gastroenteritis is suspected 2, 7
The Centers for Disease Control and Prevention recommends not prescribing antibiotics for presumed viral gastroenteritis, as they provide no benefit and may cause harm 2, 7