Approach to the Patient with Suspected Enteric Infection

Enteric infections may manifest as gastroenteritis, secretory diarrhea, bloody diarrhea, or enteric fever. The major cause of foodborne gastroenteritis worldwide is norovirus, but a variety of other viruses, enteric bacteria, and parasites can cause clinical disease. The most common cause of traveler’s diarrhea is enterotoxigenic Escherichia coli. Bloody or mucoid stools, fever, and cramping abdominal pain should prompt cultures to identify Shigella, Salmonella, Campylobacter, Shiga toxin-producing E. coli, and Yersinia species. Molecular testing can frequently identify the infectious agent but not its antimicrobial susceptibility. Oral rehydration therapy and antidiarrheal agents are preferred for afebrile patients without bloody stools or severe dehydration, with antibiotic therapy recommended for more severe cases and for traveler’s diarrhea when testing is not practical.