Infectious diarrhea is very common; its severity ranges from uncomplicated, self-limiting courses to potentially life-threatening disease. A rapid diagnostic workup providing detailed information on the suspected pathogen should be performed only in patients at risk, analyzing one single stool sample for Salmonella, Shigella, Campylobacter, and Norovirus. In the presence of risk factors, such as a history of antibiotic exposure within the last 3 months, testing for Clostridium difficile should be performed. Immunocompetent patients do not require specific antibiotic therapy. Exceptions exist in patients with severe comorbidities, immunodeficiency, fever/SIRS, and in patients with Shigella or C. difficile infection. Empirical antibiotic treatment should be considered in patients with fever and/or bloody diarrhea and in patients at risk. In patients with traveler's diarrhea, microbiological diagnosis is required only in patients with fever, bloody diarrhea, prolonged course of disease (more than 5 days), severe clinical course with hypotension or dehydration, and during outbreaks. In these patients one single fecal sample should be collected for stool cultures of Campylobacter, Shigella, and Salmonella, as well as microscopic examination for amoebiasis and Giardiasis. The main therapeutic measure for infectious diarrhea is sufficient oral rehydration. As in community-acquired diarrhea, azithromycin or ciprofloxacin are recommended-taking into account local antimicrobial resistance in the country of travel and possible side effects.
Keywords: Campylobacter; Clostridium difficile; Diarrhea, nosocomial; Infectious diarrheal disease; Shigella.