In this week’s Case Record of the Massachusetts General Hospital, a 30-year-old man was seen in the emergency room because of the acute onset of diarrhea 2 days after his return from a trip to the Caribbean. He was afebrile, and the diarrhea was watery without blood. A diagnostic test was performed.
Diarrhea is a common affliction of international travelers, affecting 10 to 50% of travelers, depending on the duration and type of travel. Diarrhea can be acute or chronic, and invasive (containing blood, mucus, or both) or watery.
• How do patients with invasive enteropathies present?
Patients with acute invasive enteropathies typically present with fever and frequent bowel movements that contain mucus or blood or both; the mucus or blood often contains leukocytes.
• What are the causes of invasive bacterial enteropathies?
Causes of invasive bacterial enteropathies in adults include campylobacteriosis, salmonellosis, shigellosis, enteroinvasive Escherichia coli, and yersiniosis, among others. Vibrio parahaemolyticus, which is most commonly reported in Asia, can cause either bloody or watery diarrhea and is usually associated with the ingestion of seafood.
Morning Report Questions
Q: When is microbiologic evaluation of stool indicated?
A: Microbiologic evaluation of stool is not usually indicated for most travelers with acute watery diarrhea, such as this patient, since the illness is usually self-resolving or can be treated empirically with hydration, agents that control symptoms, or antimicrobial agents. In contrast, microbiologic evaluation of stool is usually indicated for patients with evidence of an invasive enteropathy, those with persistent diarrhea, and those whose illness is part of an outbreak that has potential public health importance and has an uncertain cause.
Q: What is the recommended treatment for travelers’ diarrhea?
A: Azithromycin is an agent of choice for the treatment of persons with cholera and those with travelers’ diarrhea. Many strains of campylobacter are now resistant to fluoroquinolones, and the Haitian strain of cholera has reduced susceptibility to ciprofloxacin, a pattern associated with clinical and microbiologic failure in cholera patients.