Parasitology Research

, 104:341 | Cite as

Association of Blastocystis subtype 3 and 1 with patients from an Oregon community presenting with chronic gastrointestinal illness

  • Morris S. JonesEmail author
  • Christopher M. Whipps
  • Robert D. Ganac
  • N. Ryan Hudson
  • Kenneth Boroom
Original Paper


Chronic gastrointestinal illness of unknown etiology is a significant problem in the United States. Using a real-time LightCycler PCR assay we detected Blastocystis in nine patients from a metropolitan area of Corvallis, Oregon who presented with diarrhea, abdominal pain, fatigue, joint pain, skin rash and psychiatric co-morbidity. Phylogenetic analysis identified six infections with Blastocystis sp. subtype 3, and one with subtype 1, using the standard Stensvold nomenclature. Most patients with subtype 3 had previously tested negative with conventional parasitological diagnostics, had been symptomatic for over 4 years, and reported antibiotic failure.


Irritable Bowel Syndrome Skin Rash Tinidazole Nitazoxanide Blastocystis Infection 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



We would like to thank Dr. Greg Hiser for many discussions about the clinical symptoms and real-time PCR.

The work reported herein was funded and performed under United States Air Force Surgeon General-approved Clinical Investigation No. FDG20070010N. This study was also funded by the Blastocystis Research Foundation. The experiments comply with the current laws of the country in which they were performed.

The views expressed in this material are those of the authors, and do not reflect the official policy or position of the U.S. Government, the Department of Defense, or the Department of the Air Force.


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Copyright information

© US Government 2008

Authors and Affiliations

  • Morris S. Jones
    • 1
    Email author
  • Christopher M. Whipps
    • 2
  • Robert D. Ganac
    • 1
  • N. Ryan Hudson
    • 1
  • Kenneth Boroom
    • 3
  1. 1.Clinical Investigation FacilityDavid Grant USAF Medical CenterFairfieldUSA
  2. 2.Department of MicrobiologyOregon State UniversityCorvallisUSA
  3. 3.Blastocystis Research FoundationCorvallisUSA

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