When I first set out to uncover the root cause of my Hashimoto’s, I took an inventory of all of my symptoms to find an underlying connection. In creating my own personal health timeline, I was able to see how the symptoms I was experiencing developed over the years, and found a common thread that kept leading me back to gut infections.
Over the last several years of working with people with Hashimoto’s, I’ve found that many of those with chronic hives often have the gut protozoan parasite Blastocystis hominis, and that eradicating the protozoa can resolve hives, irritable bowel syndrome (IBS), and even Hashimoto’s. Scientists in Bosnia first published this connection in 2015, though I’ve seen it clinically since 2013.
Many improvements in symptoms and a reduction in antibodies can happen after addressing a Blastocystis hominis infection, and I’d like to share just how you can do that.
In this article, I’ll cover:
- The symptoms of a “Blasto” infection
- The connection between Blastocystis and hives
- How Blastocystis can cause IBS and gut issues
- Treatments to address the infection
- Common co-occurring infections
My Personal Health Timeline
My own health troubles started during my freshman year in undergrad, after catching “mono” — a common viral infection that is caused by the Epstein-Barr virus. Prior to this infection, I was a bright-eyed, bushy-tailed, and energetic young woman.
The summer before I started college, I would wake up at 5:30 or 6 am each morning so that I could go to the gym, before starting work at 8 or 9 am in the pharmacy. I loved my job as a pharmacy technician, learning about the body and medications, and couldn’t wait to start my studies to become a pharmacist! I worked full time in the pharmacy, and spent each evening studying for the pharmacy technician certification. I was proud to be the youngest person in Illinois to become a certified pharmacy technician, even before starting college. I loved learning and being out in the world!
But all of that changed during my second semester in college. I became chronically exhausted. I often slept through my morning classes, and sometimes slept through lunch and dinner. I once even slept through a midterm exam! I found myself with a strange brain fog that made studying, and even socializing, a huge effort.
Needless to say, I didn’t do too well in college that semester. I came home the following summer feeling defeated. My parents were also really concerned, as I was a shell of my former self. I slept until 2 pm each day, was moody, and lost so much weight; people suspected that I had an eating disorder.
After much rest, I got somewhat better at the end of the summer, and went back to college. I focused all of my limited energy on my studies, and was eventually able to improve my GPA to be accepted into a competitive Doctor of Pharmacy program. While I never returned to my previous levels of energy, I learned how to be more efficient, how to compensate, and how to make sacrifices, which allowed me to succeed in all of my classes.
A few years later, while in my first year of pharmacy school, I developed irritable bowel syndrome. A few years after that, I experienced anxiety attacks, acid reflux, allergies, and hives. A year or so later, I began to experience brain fog, hair loss, and joint pain. The fatigue persisted. A year later, I was diagnosed with Hashimoto’s.
Once I had the diagnosis, I began to spend a lot of time researching, as well as self-reflecting and self-experimenting, in order to overcome Hashimoto’s. My symptoms and research kept leading me back to the gut…
I learned that I not only had food sensitivities and a lack of beneficial bacteria, but I also had gut infections: small intestinal bacterial overgrowth, H. pylori, yeast overgrowth, and Blastocystis hominis.
It was at this point that I began to realize the role that infections can play in Hashimoto’s, and dove deeper into uncovering these root causes that can affect so many of us.
What is Blastocystis Hominis?
Blastocystis hominis, or “Blasto,” is a microscopic single-cell organism (protozoan) that commonly lives in the digestive tract. It is most commonly contracted through contaminated food or water sources. While there are many protozoans that normally live in your gastrointestinal tract and are harmless or even helpful, others can cause disease.
Symptoms of Blastocystis hominis can include bloating, diarrhea, nausea, flatulence, variable bowel habits, abdominal pain, hives, and fatigue. Additionally, this pathogen is notorious for causing multiple food sensitivities. A true food sensitivity, like celiac disease, usually results in a resolution of symptoms once food is removed, but Blastocystis hominis-infected people will have multiple food sensitivities and will keep getting more.
In 2015, 35 percent of my clients tested positive for Blasto. I have found this parasite in a large subset of my clients with Hashimoto’s, especially in those who develop an Epstein-Barr Virus (EBV) infection in adulthood, then are “never quite the same.” This could be because EBV and other herpes viruses feed on the amino acid arginine, and can thus cause a depletion of this amino acid, which normally suppresses Blastocystis hominis. (As a side note, arginine may also be helpful in energy production, and thus this may be a reason why we see so much fatigue with EBV).
Blastocystis has been found in some asymptomatic carriers, and researchers hypothesize that other factors can influence the pathogenicity of this parasite, such as the immune status of the host, one’s parasite load, the presence of a gut imbalance, or other factors that can influence the behavior of parasites.
Many conventional physicians have regarded this parasite as a commensal (non-harmful) organism (up to 20 percent of “healthy controls” may have Blasto without any symptoms), and will say that there is no need to treat it. However, multiple studies implicating its role in IBS and hives, (two conditions that are very commonly associated with Hashimoto’s), would suggest otherwise.
The Hashimoto’s, Hives, IBS and Blastocystis Connection
Did you know that people with Hashimoto’s are more likely to develop the skin condition chronic spontaneous urticaria (also known as chronic hives), which is manifested by widespread, itchy and swollen skin rashes? These hives can be very distressing, and they can seem to come up randomly. However, they are quite common; in fact, forty-two scientific studies have linked Hashimoto’s with chronic hives! (Some studies also suggest that taking thyroid hormone can clear up these recurring hives).
People with Hashimoto’s are also more likely to develop irritable bowel syndrome (IBS), a chronic condition that affects the large intestine and often shows up before one’s Hashimoto’s diagnosis. This condition can manifest as either diarrhea or constipation, or both, and may also cause excess gas, bloating, abdominal pain, and cramping that is often relieved after passing a bowel movement.
As mentioned previously, a Blasto infection can manifest as symptoms related to the skin (i.e. hives) and gut. Much controversy is out about this protozoan. Some studies, namely from Thailand and Mexico, suggest that this is a commensal (harmless) organism. Thus, doctors may be told that there is no need to treat it. However, studies from Europe, Australia, and the Middle East, have connected this pathogen to not just chronic hives, but also irritable bowel syndrome, both of which are very common manifestations in the early stages of Hashimoto’s. This begs the question… are hives, IBS and Blasto all connected? Let’s take a look at the current research.
Blastocystis, Hashimoto’s and Hives
Blasto may be present in up to 50 percent of people in developing countries. A study of 54 people in Egypt with chronic urticaria (hives) revealed that Blastocystis hominis was found in 61 percent of them, while only eight percent of the healthy controls had the parasite.
Researchers have suggested that the amoeboid form of Blastocystis hominis is more infective that the protozoa form, and that it can adhere better to gut cells. Interestingly, the Egyptian study found this form in 60.6 percent of the Blastocystis infected people with hives, while none of the Blastocystis infected controls had this form.
In a letter to the editors of the British Journal of Dermatology, Dr. Tilo Biedermann from the Ludwig-Maximillians University in Munich, Germany, reported that urticaria and reactions to NSAIDs subsided after treating 10 subjects infected with Blastocystis, with paromomycin 25 mg/kg, for 10 days.
Another drug, called Alinia (nitazoxanide), is an FDA-approved antiprotozoal for treating other parasites, and has been helpful in eradicating Blastocystis hominis. One study showed that it eliminated symptoms in 36 of 42 (86 percent) of patients who were put on a four day treatment of nitazoxanide. This was exciting news, as the parasite has been shown in other studies, to be highly resistant to Flagyl (metronidazole), the usual drug of choice.
A 2014 study found that almost 25 percent of people with chronic urticaria had Hashimoto’s, and addressing an underactive thyroid with levothyroxine (T4 thyroid medication) could result in a clinical remission of hives. However, I do wonder if the medication is just masking the symptoms of the parasite.
Blastocystis, Hashimoto’s and the Gut
Various studies, using many different methods for parasite identification, have found the prevalence rate of Blastocystis hominis to be between 13 to 73 percent of people with irritable bowel syndrome. As parasite detection methods are not 100 percent reliable (with many false negatives), these rates could be even higher.
Studies have found that Blastocystis species of protozoa do not invade the colonic mucosa, but they do lead to disturbances of the barrier function and increased intestinal permeability. Blastocystis breaks down secretory IgA, the protective barrier and the immune system of its infected host. Thus, Blastocystis has been shown to cause leaky gut, which we know predisposes us to autoimmunity.
The good news is, research has found that eradicating Blastocystis in cases of urticaria and IBS, often leads to the remission of both conditions. Many of my clients have been able to reduce their joint pain, fatigue, and TSH and TPO counts by eliminating Blasto as well.
I was super excited to learn that a new paper has been published in a medical journal, detailing the case of a person who saw a reduction in TSH and thyroid antibodies after the eradication of Blastocystis hominis! In this case, a 49 year-old man who presented with chronic urticaria was found to also have Hashimoto’s, even though he never had clear symptoms. Blastocystis hominis was isolated through a stool examination, and the patient was given a two-weeks treatment with metronidazole, after which the Blastocystis hominis was eradicated and the urticaria disappeared. During the four years of follow-up, the patient presented without any symptoms, thyroid hormones were normalized, and anti-thyroid antibodies declined.
I’ve found that eradicating a Blastocystis infection in a person with Hashimoto’s often leads to a remission of Hashimoto’s, with an improvement in symptoms, a reduction in food sensitivities, and a reduction in thyroid antibodies.
Testing for Blasto
If you suspect you may have a Blasto infection (like 35 percent of my clients do), you may want to consider ordering a non-invasive functional medicine stool test. Tests that check for this infection include:
- GI-MAP – This panel includes bacteria, viruses, opportunistic organisms, normal flora, parasites, and fungi. The DNA/PCR techniques that are employed by this assessment also measure one’s antibiotic resistance genes and virulence factors that contribute to pathogenicity.
- GI Pathogen Screen with H. pylori Antigen – This panel screens for ova, parasites, bacteria, fungi, yeasts, and occult blood. It also checks for antigens to Helicobacter pylori, Entamoeba histolytica, Cryptosporidium parvum, and more.
- GI Effects Comprehensive Profile – This panel from Genova Diagnostics uses DNA analysis to go beyond the standard parameters for identifying gastrointestinal disorders.
- Comprehensive Stool Analysis (Doctor’s Data Kit) – The Comprehensive Stool Analysis evaluates the status of beneficial and imbalanced commensal bacteria, pathogenic bacteria, fungi, and yeast.
According to the Blastocystis Research Foundation, “Some patients can manage symptoms with an extensive exclusion diet, which may include the exclusion of refined sugar, wheat, dairy products, rice, corn, carbonated drinks, tea, coffee, alcohol, and fruit.” Blastocystis can also cause carbohydrate intolerance. (Does this sound familiar? If you’ve read my article on the best diet for Hashimoto’s, you’ll know that many people with Hashimoto’s have managed their symptoms with similar diets.)
While diet can help to manage symptoms, it will not eradicate the pathogen. This parasite needs to be treated with antiprotozoal medications, and/or herbs with antiprotozoal activity and/or the beneficial yeast Saccharomyces boulardii.
I have seen the following protocols for eradicating Blastocystis hominis to work effectively:
- A triple therapy used in Australia combines three medications to eradicate the infection: diloxanide furoate, trimethoprim/sulfamethoxazole and secnidazole*.
- Alinia is another antiprotozoal medication that can be taken for three days on, then two weeks off, repeated twice*. (This ensures that we address more than one “life-cycle” of the parasite, so that we can access it when it’s in its more vulnerable state.)
*Keep in mind that antiprotozoal medications can lead to a yeast overgrowth, and treatment with anti-yeast herbs or a medication like Nystatin may be necessary to rebalance the gut.
Natural Treatment Options
- The beneficial yeast Saccharomyces boulardii, may help eradicate Blastocystis hominis (when two capsules are taken twice per day, for at least 30 days, but ideally for 60 days). In fact, one study found that S. boulardii was just as effective as the antibiotic metronidazole, in the treatment of a group of children who presented with gastrointestinal symptoms (abdominal pain, diarrhea, nausea-vomiting, flatulence) from the confirmed presence of Blasto by stool examination. They were given 250 mg of S. boulardii, twice a day for ten days, then tested periodically until they received a “clinical cure rate” of 94.4 percent after 30 days. This has become my go-to treatment in many cases, as I have seen excellent results from S. boulardii alone, and rarely recommend protozoal medications and aggressive protocols to eradicate Blasto anymore.
- In some cases, combing antiparasitic/anti-yeast herbs, such as oil of oregano and berberine, with S. boulardii, may be needed to treat the infection. I utilize these for a period of 60 days.
The key is to use these treatments long enough, or in a pulsed fashion, to fully eradicate Blasto. Blasto can take on four different forms during its lifecycle, and some of the forms are resistant to treatment. The forms range from the cyst stage (when infection is thought to occur), to vacuolar, amoeboid, and granular stages, until they return to cyst form, often repeating the cycle. The cyst is the most resistant form of Blasto, and is able to survive in harsh conditions because of its thick multilayered cyst wall. Therefore, it’s important to stay on a treatment long enough to eradicate the parasite during one of its other forms in the cycle.
In theory, lipase containing digestive enzymes (such as Veggie Enzymes and Pancreatic Enzymes Plus), taken while one is using other treatments for the Blasto, could help with making the parasite more vulnerable to the treatments by breaking down the cyst wall. I used to recommend lipase-containing enzymes for resistant cases of Blasto, sometimes with Arginine (which can help with eradicating it according to some researchers), along with more aggressive treatment options. As I mentioned earlier, in the last few years, I’ve had such great results with S. boulardii alone (and it’s generally well tolerated and cost-effective), that I usually start there.
Removing food sensitivities will also be very helpful for managing symptoms while recovering from Blasto.
Please be sure to work with your practitioner to determine which treatment option is best for you.
When you work with your functional medicine practitioner, be sure to ask about potential co-occurring infections. Often, Blastocystis co-occurs with H. pylori, another potential root cause and trigger of Hashimoto’s. (You can read more about H. pylori in my article here.) Some professionals will go as far as to treat a person for both infections when one or the other is found.
Some people with Hashimoto’s can completely reverse their condition just by going gluten and dairy free, and some see no improvement at all from doing so. Gluten and dairy are common leaky gut triggers, but there are many others. Testing for gut infections could be an important next step on your road to uncovering your root causes. If this sounds like your story, I urge you to listen to your body — or should I say, gut feeling? 🙂 — and look into other possible root causes — like a Blasto infection.
Addressing infections can make a dramatic difference on your health journey. However, some people may need to dig further and address the other root causes of their remaining symptoms.
I cover steps on how to search for your personal root causes, as well as a Blastocystis hominis protocol, in my book, Hashimoto’s Protocol… so be sure to check it out if you haven’t done so already.
I hope this information helps you on your journey!
P.S. Be sure to sign up for my weekly newsletter to get a free chapter of my first book, recipes, a Thyroid Diet start guide, and notifications about upcoming events. And join me on Facebook to keep in contact with our Hashimoto’s community!
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Note: Originally published in September 2015, this article has been revised and updated for accuracy and thoroughness.