Acute Gastroenteritis- Author: Dr. Brian Geyer
* Do both vomiting and diarrhea have to be present? No
1996 AAP guidelines, 2016 ACG guidelines, and 2017 IDSA guidelines all note diarrhea illness but may be vomiting predominant.
* Studies use more vague definitions like:
> 1 episode of vomiting and/or > 3 episodes of diarrhea in 24 hours without known chronic cause like inflammatory bowel disease.
Diarrhea is at least 3 unformed stools per day.
Acute episode 29 days
* Patients in the ED may present with only some of these symptoms depending their time in course of illness.
* There is abundant literature on pediatric AGE but sparse research on AGE in adults. Therefore, many recommendations are extrapolated from the pediatric literature.
* 70% of US cases are estimated to be caused by viruses, norovirus being most common.
o 26% norovirus
o 18% rotavirus
* Among bacterial causes:
o 5.3% Salmonella, most common
o 5.3% Clostridium
o 3% Campylobacter
o 3% parasitic infections
* Large portion, 51%, have no cause identified. (In ED patients)
* Interestingly, 79% of cases never have a cause identified (not ED specific)
* In ED patients, only 25% ever have a cause identified, this increases to 49% when a stool sample is obtained. (not ED specific)
* Food poisoning is responsible for 5% of AGE but results in 30% of deaths. Most commonly:
Salmonella, Clostridium perfringens, and Campylobacter
Majority of foodborne illness is still viral, mostly norovirus
* E Coli is normal in the gut, but two most common causes are:
Shiga toxin Ecoli (STEC) AKA enterohemorrhagic Ecoli (EHEC) - causes Hemolytic Uremic Syndrome in 5-10%
Entertoxigenic Ecoli (ETEC) - causes traveler's diarrhea
Both cause self-limited illness.
* Appendicitis: In the peds literature, misdiagnosis of appendicitis as AGE leads to 47% absolute increased risk of perforation. Suggestive findings include:
Migration of pain to RLQ
RLQ tenderness on exam (initial or repeat)
Absence of diarrhea
Pain not improved with episodes of diarrhea
Negative factors include multiple ill family members, recent international travel,