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06:05
Development of a Negative Selectable Marker for Entamoeba histolytica
Published on: December 13, 2010
Dientamoeba fragilis: the unflagellated human flagellate
1Department of Microbiology and Immunology, College of Medicine, Sultan Qaboos University, Muscat, Sultanate of Oman.
British Journal of Biomedical Science
|May 5, 2000
Summary
Dientamoeba fragilis, a flagellate protozoan, causes gastrointestinal illness in humans. Diagnosis requires stained fecal smears, and symptomatic cases are treatable with specific medications.
Area of Science:
- Microbiology
- Infectious Diseases
- Parasitology
Background:
- Dientamoeba fragilis is a globally distributed pathogenic protozoan parasite.
- Reclassified as a flagellate based on electron microscopy and immunological data, it resembles Histomonas and Trichomonas but lacks a flagellum.
- A resistant cyst stage is not evident, suggesting trophozoites have limited survival outside the host.
Purpose of the Study:
- To review the characteristics, transmission, clinical manifestations, diagnosis, and treatment of Dientamoeba fragilis infections.
Main Methods:
- Review of existing literature on Dientamoeba fragilis.
- Analysis of diagnostic methods, focusing on the necessity of stained fecal smears.
- Evaluation of treatment strategies for symptomatic infections.
Main Results:
- D. fragilis infections can be acute or chronic, affecting both children and adults.
- Common symptoms include abdominal pain, persistent diarrhea, appetite loss, weight loss, and flatulence.
- Co-infection with Enterobius vermicularis suggests pinworm ova may facilitate transmission.
Conclusions:
- Definitive diagnosis relies on observing the characteristic nuclear structure in permanently stained fecal smears.
- Treatment is indicated for symptomatic individuals, with iodoquinol, tetracycline, and metronidazole showing efficacy.
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