Bacterial Gastroenteritis Diagnosis and Clinical Presentation

Definition and Diagnostic Criteria

The World Health Organization defines diarrhea as passage of 3 or more loose or liquid stools per 24 hours, or more frequently than is normal for an individual person 1
Acute gastroenteritis is characterized by acute watery diarrhea (including cholera) or acute bloody diarrhea (including dysentery) that lasts <7 days 1
The term "gastroenteritis" specifically refers to inflammation of the gastrointestinal tract manifesting as diarrhea, with or without accompanying symptoms 1, 2

Enteric fever (typhoid and paratyphoid fever) caused by Salmonella enterica serovar Typhi and Paratyphi can present with fever, headache, lethargy, malaise, and abdominal pain without diarrhea 3
While enteric fever has a gastrointestinal portal of entry, diarrhea is an uncommon feature of this condition 3
This condition is classified separately from bacterial gastroenteritis, as it represents a bacteremic illness rather than a primary gastrointestinal infection 3

Clinical presentations suggestive of infectious diarrhea include visible blood in stool, fever, abdominal pain, and vomiting with diarrhea 4
Stool testing should be performed for bacterial pathogens when diarrhea is accompanied by fever, bloody or mucoid stools, severe abdominal cramping or tenderness, or signs of sepsis 4, 5

Certain conditions may mimic bacterial gastroenteritis but have different diagnostic criteria, such as Clostridium difficile infection, which can present with severe leukocytosis even in the absence of abdominal pain or diarrhea 6
The absence of diarrhea should prompt consideration of alternative diagnoses rather than bacterial gastroenteritis 1, 2
For patients with fever without diarrhea but with relevant travel history or exposures, consider enteric fever rather than bacterial gastroenteritis 3
Blood cultures are recommended for patients with suspected enteric fever or bacteremia, especially in those with systemic manifestations of infection 5