Diarrhea, Traveler's

Key Features

Essentials of Diagnosis

• Usually a benign, self-limited disease occurring about a week into travel

• Prophylaxis not recommended unless there is a comorbid disease (inflammatory bowel syndrome, HIV, immunosuppressive medication)

• Single-dose therapy with a fluoroquinolone usually effective if symptoms develop

General Considerations

• Whenever a person travels from one country to another—particularly if the change involves a marked difference in climate, social conditions, or sanitation standards and facilities—diarrhea may develop within 2–10 days

• Bacteria cause 80% of cases

• Contributory causes include

  • Unusual food and drink

  • Change in living habits

  • Occasional viral infections (adenoviruses or rotaviruses)

  • Change in bowel flora

• Traveler's diarrhea is a risk factor for development of irritable bowel syndrome

Etiology

• Most common

  • Enterotoxigenic E coli

  • Shigella

  • Campylobacter

• Less common

  • Aeromonas

  • Salmonella

  • Noncholera vibrios

  • E histolytica

  • G lamblia

  • Adenoviruses

  • Rotavirus

• Chronic watery diarrhea

  • E histolytica

  • G lamblia

  • Tropical sprue (rare)

Clinical Findings

Symptoms and Signs

• There may be up to 10 or more loose stools per day

• Abdominal cramps, nausea, occasionally vomiting

• Fever is rare

• When cause is enterotoxigenic E coli

  • Stools are usually watery

  • Fever is not usually present

• When cause is invasive bacterial pathogens (eg, Shigella, Campylobacter, Salmonella)

  • Stools may be bloody

  • Fever may be present

• Course of illness

  • It usually subsides spontaneously within 1–5 days

  • However, 10% remain symptomatic for a week or longer

  • In 2%, symptoms persist for longer than a month

Diagnosis

Laboratory Tests

• In patients with fever and bloody diarrhea, stool culture is indicated, but in most cases cultures are reserved for those who do not respond to antibiotics

Treatment

Medications

• For most patients, symptomatic therapy with loperamide is all that is required provided there is no systemic illness (fever ≥ 39°C) or dysentery (bloody stools), in which case antimotility agents should be avoided

• Packages of oral rehydration salts to treat dehydration are available over the counter in the United States (Infalyte, Pedialyte, others) and in many foreign countries

• Loperamide (4 mg loading dose, then 2 mg after each loose stool to a maximum of 16 mg/day) with a single oral dose of ciprofloxacin (750 mg), levofloxacin (500 mg), or ofloxacin (200 mg) cures most cases

• If diarrhea is severe, associated with fever or bloody stools, or persists despite single-dose of a fluoroquinolone, then 1000 mg of azithromycin should be given

• Azithromycin is drug of choice for pregnant women and for cases due to invasive bacteria

• Rifaximin, a nonabsorbable rifampin-like drug, is effective at 200 mg orally three times daily or 400 mg orally twice daily for 3 days. Because ...