Blastocystis hominis and travelers
Muhammad R Sohail1, Philip R Fischer
1Division of Infectious Diseases, Department of Medicine, Mayo Clinic College of Medicine, 200 First Street SW, Rochester, MN 55905, USA.
Travel Medicine and Infectious Disease
|February 13, 2007
Summary
Blastocystis hominis (B. hominis) is a common intestinal protozoan found in travelers returning from tropical regions. Diagnosis involves stool examination, and treatment decisions for B. hominis infection require careful consideration of symptoms and potential co-infections.
Area of Science:
- Medical Parasitology
- Infectious Diseases
- Travel Medicine
Background:
- Blastocystis hominis (B. hominis) is a ubiquitous unicellular protozoan parasite with a global distribution.
- Infections are more prevalent in developing nations and among travelers returning from tropical areas.
- Clinical manifestations associated with B. hominis include gastrointestinal symptoms like nausea, abdominal pain, and diarrhea.
Purpose of the Study:
- To review the diagnosis, clinical significance, and management of Blastocystis hominis infections in travelers.
- To address the diagnostic challenges and treatment controversies surrounding B. hominis.
Main Methods:
- Diagnosis is primarily achieved through permanently stained smears of unconcentrated stool specimens.
- Clinical evaluation of symptomatic travelers is crucial to identify potential co-pathogens.
- Treatment options, when indicated, commonly include metronidazole or trimethoprim-sulfamethoxazole (TMP-SMX).
Main Results:
- The presence of B. hominis in symptomatic travelers warrants investigation for other co-existing infections.
- The pathogenicity of B. hominis remains debated, complicating treatment decisions.
- Preventive measures emphasize food and water safety due to the fecal-oral transmission route.
Conclusions:
- Clinicians must consider B. hominis in the differential diagnosis of gastrointestinal illness in returned travelers.
- A thorough workup for other pathogens is recommended when B. hominis is detected in symptomatic individuals.
- Public health strategies should focus on educating travelers about safe food and water practices to prevent fecal-oral transmission.
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