What are the causes and treatment options for persistent travelers' diarrhea (gastroenteritis) lasting more than 7 days?

From the Guidelines

If you've been experiencing traveler's diarrhea for more than 7 days, you should seek medical attention as this is considered persistent diarrhea and may require specific treatment. The standard approach typically involves antibiotics such as azithromycin (500mg once daily for 3 days) as the first-line agent, especially in cases of dysentery or acute watery diarrhea with greater than mild fever, due to its efficacy and safety profile 1.

Key Considerations

• Azithromycin has been shown to be superior to levofloxacin in achieving clinical cure in settings with high rates of FQ-resistant Campylobacter spp. 1.
• The use of fluoroquinolones (FQs) is limited due to increasing resistance among common bacterial enteropathogens, including Campylobacter, Enterotoxigenic E. coli, Shigella, and non-typhoidal Salmonella 1.
• Rifaximin, a nonabsorbable antibiotic, has demonstrated comparable efficacy to FQs in non-invasive TD caused by diarrheagenic E. coli, but is less effective for invasive pathogens 1.

Treatment Approach

• While waiting for medical care, continue fluid replacement with oral rehydration solutions, and consider adding loperamide (Imodium) to reduce frequency of bowel movements.
• Prolonged diarrhea can indicate a more serious infection, parasitic disease, or underlying condition, which is why medical evaluation is important.
• Stool testing may be necessary to identify specific pathogens requiring targeted treatment, especially if symptoms persist or worsen over time 1.

Important Notes

• Antibiotic treatment is not without potential adverse consequences, including the risk of acquiring ESBL-PE and altering the individual's microbiota 1.
• Early and effective treatment of TD may mitigate the risk of chronic health consequences, such as IBS, although further research is needed to confirm this benefit 1.

From the FDA Drug Label

The duration of treatment depends upon the severity of infection The usual duration is 7 to 14 days; however, for severe and complicated infections more prolonged therapy may be required. Infectious Diarrhea Mild/Moderate/Severe 500 mg q 12 h 5 to 7 Days

The causes of persistent travelers' diarrhea are not specified in the label. Treatment options for persistent travelers' diarrhea (gastroenteritis) lasting more than 7 days may include prolonged therapy with ciprofloxacin, as the label states that for severe and complicated infections, more prolonged therapy may be required 2. Key considerations for treatment include:

• Severity of infection
• Susceptibility of the causative organism
• Integrity of the patient’s host-defense mechanisms
• Status of renal function and hepatic function The label recommends a dose of 500 mg q 12 h for infectious diarrhea, but the usual duration of treatment is 5 to 7 days.

From the Research

Causes of Persistent Travelers' Diarrhea

• Travelers' diarrhea is usually acquired through ingestion of food and water contaminated by feces 3
• Most cases are due to a bacterial pathogen, commonly Escherichia coli, and occur within the first few days after arrival in a foreign country 3
• Children are at particular risk of developing travelers' diarrhea 3

Treatment Options for Persistent Travelers' Diarrhea

• For mild travelers' diarrhea, the use of antibiotic is not recommended, but the use of bismuth subsalicylate or loperamide may be considered 3
• For moderate travelers' diarrhea, antibiotics such as fluoroquinolones, azithromycin, and rifaximin may be used, and loperamide may be considered as monotherapy or adjunctive therapy 3
• For severe travelers' diarrhea, antibiotics such as azithromycin, fluoroquinolones, and rifaximin should be used 3
• If an agent is not identified or the patient has not responded to specific therapy, empirical treatment with an antimicrobial drug directed toward common bacterial enteropathogens may be employed 4
• Antiprotozoal therapy may be employed empirically if the patient's condition does not respond to initial treatment 4
• Symptomatic treatment and reassurance may be given to patients whose conditions do not respond to empirical therapy and a gastroenterologic workup 4

Management of Persistent Travelers' Diarrhea

• Fluid replacement is the principal therapeutic modality for travelers' diarrhea 5
• Oral rehydration therapy is the mainstay for managing water and electrolyte depletion 6
• Early empiric use of antimicrobial agents including trimethoprim-sulfamethoxazole or quinolone agents offers an excellent means of treating traveler's diarrhea and preventing its potential complications 5
• Travelers who develop dysentery, high fever, or prolonged diarrhea lasting more than 10-14 days should seek medical attention for specific diagnosis and appropriate antimicrobial therapy 5