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Date of last update: 10/15/2017.

Forum Name: Gastroenterology Topics

Question: Treatment options for Blastocystis?

 marplz - Fri Aug 13, 2010 7:19 am


After going through a bit of an ordeal of intermittent diarrhea with huge abdominal bloat, a lot of upper abdominal pain and badly odorous gas, I was diagnosed with an intestinal infection with Dientamoeba Fragilis and Blastocystis about a year ago. In spite of extensive diagnostics, no other pathogens or conditions could be identified. Specifically, Helicobacter was excluded by biopsies of stomach and duodenum, and no other infections were discovered in several series of stool examinations for parasitic ova, bacteria and other pathogens. Tumors were excluded by 24-hour urine test and abdominal CT and ultrasound. Blood and urine samples were studied and nothing significant found.

Hence an attempt was made to eradicate the amoeba and Blastocystis with Metronidazole and TMP-SMX. The treatment had unpleasant side effects as expected, and my condition was much improved after treatment. The intermittent diarrhea was over, and I recovered from the side effects quickly. Bowel motions normalized slowly over the course of a couple of months. Then I got intermittent diarrhea and abdominal pain again, but nowhere near as intense as before the treatment. We took stool samples again, result: NO Dientamoeba, but Blastocystis was still (or again?) there. This was over half a year ago. We have since repeatedly tried to eradicate the Blastocystis, all to no avail. Treatment so far has included the following drugs: Metronidazole & TMP-SMX together; Metronidazole alone; Nitazoxanide alone (3-day course); Metronidazole & Paromomycin together. After each treatment, the Blastocystis has always shown up in stool samples again, and we have never seen the amoeba again since the first treatment. Light intermittent diarrhea and upper abdominal pain, together with moderate flatulences (more than normal though) continue to plague me.

(Yes, I do appreciate that the pathogenic character of Blastocystis is disputed. However, lacking identification of any other cause of illness, and knowing that I am generally fit and healthy, it appears reasonable to attempt treating against the Blastocystis. After all, the pathogenicity of Dientamoeba is also disputed by many, yet my condition approved hugely after treatment... and the amoeba appear to have been removed effectively!)

Now here is the question: what is the recommended treatment against Blastocystis? It appears that there are a dozen different kinds of Blastocystis, but from the microscopy done at the lab, one doesn't find out which one it is... and they may not all respond to the same drugs. Plus, they have this fairly complex lifecycle with a cyst stage etc. which may make it hard to get rid of them. Any recommendations on how the get rid of the Blastocystis would be highly appreciated.

Thanks, regards.
 Dr.M.jagesh kamath - Sun Sep 05, 2010 10:42 am

User avatar Hello, The question posed by the following article is self-explanatory."Blastocystis hominis: Pathogen or Fellow Traveler?" Am. J. Trop. Med. Hyg., 35(5), 1986, pp. 1023-1026.As to whether the parasite is just associated with symptomatic disease caused by other organisms has been the question.The authors in the above communication conclude thus."We believe that when an apparently symptomatic B. hominis infection responds to therapy, the improvement probably represents elimination of some other undetected organism causing the infection".Some of those who had persisting symptoms ultimately were diagnosed as irritable bowel syndrome.Hope this gives some insight to your condition.
Best wishes.

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