Parasitology Research

, Volume 96, Issue 4, pp 273–275 | Cite as

Blastocystis hominis and the evaluation of efficacy of metronidazole and trimethoprim/sulfamethoxazole

  • Davood. Dorostkar MoghaddamEmail author
  • E. Ghadirian
  • M. Azami
Original Paper


Blastocystis hominis is commonly found in the intestinal tract of humans. Although the pathogenicity of this unicellular parasite is controversial, anti-protozoan agents are usually administered to infected individuals. At present, the first choice of chemotherapeutic agent is Metronidazole as described in the literature. In this study, we evaluated the effects of metronidazole and Trimethoprim/Sulfamethoxazole (TMP/SMX) on persons infected with B.hominis. A total of 104 subjects infected with B. hominis were admitted to the laboratory from 2002 to 2003. All individuals were non-immunocompromised and subjects were monitored for 1 year after treatment. All stool samples were microscopically examined after staining with iodine and by culturing in an egg slant medium. Of the 104 infected individuals (52±16 years of age, M:F=60:44) with B. hominis infection, 28 were discharging large numbers of parasites before treatment. Of 28 severely infected individuals, 12 were treated with metronidazole/250–750 mg at a regimen of 3x/day/10 days and 4 of the 12 were eradicated. Nine individuals were treated with TMP/SMX/1tab at a regimen of 3x/day/10 days and 2 of the 9 were eradicated. For severe B. hominis infections, it appears that metronidazole and TMP/SMX are effective in some individuals, but not all.


Irritable Bowel Syndrome Metronidazole Infected Individual Stool Sample Pentamidine 
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Copyright information

© Springer-Verlag 2005

Authors and Affiliations

  • Davood. Dorostkar Moghaddam
    • 1
    Email author
  • E. Ghadirian
    • 2
  • M. Azami
    • 1
  1. 1.Department of Parasitology and Mycology, School of MedicineIsfahan University of Medical SciencesIsfahanIran
  2. 2.Shahid Mohammad Montazeri HospitalIsfahan University of Medical SciencesIsfahanIran

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