Blastocystis hominis is a common gut parasite found here in Byron Bay, Australia and throughout the warmer climates of the world in general.
There is still debate on whether it is a problem bug.
If you are reading this then chances are you have found a Blastocystis hominis infection and are wondering what it is and what to do about it.
Read on learn more about this troublesome little gut bug.
What is Blastocystis hominis?
Digging into the research it appears that Blastocystis hominis has been a tough nut to crack.
Originally it was classified as a “harmless intestinal yeast” only to be reclassified as a protozoan when researchers had the ability to sequence the RNA (1).
It is extremely common in the human intestinal tracts and has been debated for over 20 years as to whether it is a normal resident or a problem.
That being said it is associated with many symptoms of illness (2).
Protozoan bugs are eukaryotic organisms making them much more complex compared to prokaryotes (bacteria and archaea.)
The headline for eukaryotic organisms is specialisation. Instead of a much simpler and smaller cell, eukaryotes have specialised internal organelles (3).
How Do You ‘Catch’ Blastocystis? – Routes Of Infection
The route of infection for Blastocystis is via the fecal-oral route.
Be cautious of any and all unfiltered tank water, especially in areas rich in wildlife.
It is quite simple to filter the parasite out so if you are considering living on tank water (as much of rural Australian’s do) then I would recommend a whole-house filter so that your shower, bath and washing up water is all properly filtered.
Personal note: I will always be interested in Blastocystis. In my late 20’s I moving to the Byron Bay area and contracting it from contaminated tank water.
I spent three years battling the bug.
I finally cleared it, but still suffer residual gut issues from the infection.
There have been numerous visits to multiple doctors. The first doctor ran the stool test that came back positive for Blastocystis hominis and then suggested
A) not doing anything as many doctors don’t consider it a parasite
B) Taking an antibiotic that had roughly a 60% chance of success (his words not mine)
C) If all else fails that there a triple therapy that was showing good success formulated by the centre for digestive diseases. Basically carpet bombing your gut from what I could make out.
Symptoms and Health Issues In Blastocystis hominis Infections
The list of symptoms associated with a Blastocystis infection is long including
- abdominal pain
- alternating diarrhoea and constipation…the list goes on (1).
How common is Blastocystis?
A study performed in Turkey in 2015 sheds some light on that question.
The researchers looked at over 50,185 patients that presented to the Parasitology Laboratory at Yuzuncu Yil University. From that sample 0.54% came back positive for Blastocystis hominis.
Of those 0.54% (n = 275) 70.2% presented with symptoms associated with B. hominis (abdominal pain, diarrhea, anorexia etc) (4).
I would agree that there is the possibility that B. hominis is simply a commensal organism (natural/normal resident of the gut) that becomes opportunistic under certain conditions.
Along with the laundry list of possible symptoms (food intolerance is interesting here) there have been comments that B. hominis could be linked to IBS.
A few interesting case studies outline remission in both hashimoto’s disease (autoimmune hypothyroid) as well as ulcerative colitis (a type of inflammatory bowel disease) when Blastocystis hominis was eradicated (5, 6).
These connections less studies but I figured they were worth mentioning.
Testing for Blastocystis – Recommended Gut Testing
You really need to properly test if you suspect a parasite infection. If you don’t test you’ll be shooting in the dark!
There are a number of different stool tests available to screen for parasites.
One tests, offered by many doctors, and covered by medicare is what is called a PCR (polymerase chain reaction) test. It is quite sensitive and can detect fragments of DNA from the top 10 major pathogens (Blastocystis being one of them). It will also screen for a parasite called Dientameoba fragilis which is a common co-infection often found with Blastocystis.
Combining this test with a comprehensive stool analysis (CDSA) will give you more information on other possible infections including bacterial overgrowths and fungal infections.
Image: A PCR stool test ordered from the doctor showing Blastocystis and Dientamoeba infections
Image: The same PCR stool test showing no infections
Conventional Treatment Options For Blastocystis hominis Infections
Conventional medicine first looks to metronidazole (aka flagyl) as the first line of defence against Blastocystis hominis.
Personal note: In my case this was the treatment I was prescribed by my GP. I had spent over 6 months with stomach pain when I ate, diarrhea daily, bloating and flatulence.
I have been resistant to taking antibiotics in my life, attempting to reduce my exposure as much as possible. Taking metronidazole completely floored me.
It was evident that serious upheaval in my gut was happening.
My symptoms never completely cleared but they subsided for a month and then returned to full symptomatic force within two months.
Researching Blastocystis hominis treatment it seems clear that metronidazole is a bit of a fingers crossed kind of treatment.
A placebo control treatment trial (a real gold standard in science) compared metronidazole and a placebo in 76 patients that had only screened for B. hominis (other patients that had multiple co-infections were removed from the trial.)
Of the group that had been given metronidazole, 80% showed clearance of B. hominis from their stool samples.
Sounds great right!
A retest after six months found that only 48% (n = 40) of the group receiving the antibiotic had actually cleared the infection (9).
Anecdotally I have seen this very case of clearance (or clearance of symptoms) for period of time and then a full relapse of symptoms in dozens of people here in Byron Bay area of Australia.
Personally I have experienced this as well. This is why it is so important to re-test after treatment.
Herbal Treatments for Blastocystis hominis Infection
Antibiotics scare me.
The more I learn the more I’d like to avoid them for anything short of absolutely necessary.
The drawbacks of antibiotic use but for the time being the headlines on why to generally avoid them include
- Disrupted gut microbiome
- Evolution of resistant super bugs when they are not 100% effective (remember the recurrence of blasto 6 months later from the study above)
- They are quite taxing on your body (immune system and liver particularly)
Now that’s not to say that herbal antimicrobials don’t tax your system.
Anything that knocks back microbes is going to have some negatives. One point that is essential in my opinion is first building yourself back up before moving into the killing phase. It is common for people to want the silver bullet that they can take and fix their gut.
Often times lifestyle factors are not even considered. There are a few factors that I would seriously consider when considering a strategy to deal with gut infections.
- Remove all offending foods. You want to work on fixing your inflamed and possibly leaky gut before taking antimicrobials.
- Be sure that you are have at least one bowel movement each day. Constipation is a serious concern if you are killing off parasites. You need to be sure that you are eliminating waste from your body!
- Definitely eliminate all alcohol! This is a no brainer, but something that most people ignore. You don’t want to be drinking any alcohol while you are preparing and then going through the killing phase.
- Digestive enzymes and/or hydrochloric acid could be indicated. Gut parasites impair digestive function. Any food that you are not properly breaking down and assimilating becomes taxing on the GI tract. It is a good idea to look into digestive enzymes/HCL to get everything running smoothly. There are some possible contraindications when it comes to HCL so please read this article by Chris Kresser before proceeding
- Repair the gut with supplements and herbs recommended by your practitioner.
Depending on how you feel physically that could do it.
Personally I felt 50% better after removing suspect foods, eliminating alcohol and taking some soothing gut supplements. The main point is that you are focusing on reducing inflammation in your gut by foods that could be irritants, improving digestion and elimination, and working at repairing your gut before you attempt to eliminate the parasites.
Most conventional, and even alternative approaches go straight to the killing phase.
A major issue with this is the stress the antimicrobials (or antibiotics) puts on your body. If you have a leaky, inflamed gut on top of that stress it is a recipe for disaster.
Western herbal medicine has a long history of treating gut infections. Working with a herbalist or naturopath that specialises in digestive health is important.
Herbal medicines that help to treat Blastocystis hominis infections include the following herbs like:
- Berberine rich herbs (Coptis chinensis, Barberry, Oregon Grape Root, Goldenseal)
- Oregano leaf and oil
- Olive leaf extracts
- Wormwoods (including Artemisia annua, Artemisia absinthium)
- Black Walnut
- Pomegranate husk tincture
- Probiotics have shown to be helpful as well. Especially the Saccharomyces cerevisiae var. boulardii CNCM I-745 strain.
For a deeper dive into the herbal antimicrobials that have been successful see – Herbal Treatment For Blastocystis
Those Living With Blastocystis hominis Infections
I have spent the past two years battling Blastocystis hominis.
First I went the conventional route. It helped for a month and then my symptoms came back with a vengeance.
There was no chance of reinfection as I became overly cautious of the possibility and carried my own spring water everywhere.
It took three rounds of herbal antimicrobial herbs, a complete rehaul of my diet and a focus on biofilms to successfully treat Blastocystis hominis.
It was hard.
To everyone out there in the same boat I feel your pain.
This infection (and the handful of co-infections) has completely changed my life. Now I am on the track to completing my Health Science degree in Western Herbal Medicine so that I can help others who are in the same position I was in.
As I am still a student all I can do is share what I have (and am) learning on Blastocystis infections and hope that it helps.
Now I want to hear from you. What experience do you have with Blastocystis or other related gut infections. Leave a comment in the section below.
References and Resources