Parasite Infection, B12 Deficiency and Gut Symptoms – A Case Study

blastocystis hominis gut testing option byron bay herbalist australian naturopath

Blastocystis hominis is a common parasite here in the Byron Bay region and Australia in general. As a protozoan parasite infection it is often transmitted through contaminated water (think unfilter rainwater for anyone living out of towns and cities). This article will cover one particular case of Blastocystis infection coupled with low B12 status and high homocysteine levels.

Further reading

The patient presented with mild stomach complaints including flatulence, bloating and heaviness in the stomach after eating as well as on and off mild fatigue. He had a history of travel in South America, Thailand and Bali.

Standard testing revealed a number of interesting things that helped to explain his symptoms including:

  • Blastocystis parasite infection
  • High normal MCV – mean corpuscular volume
  • High normal MCH – mean corpuscular haemoglobin
  • Normal serum B12
  • Low holotranscobalamin – active B12
  • High homocysteine
  • Normal haemoglobin

Digging Into The Findings

Parasite Infections Found

Here we can see a number of important points. First and foremost a parasite infection has been found. Even though Blastocystis spp. is a difficult parasite infection to treat I would still consider this a win.

Let me explain.

Many people present with similar gut issues and are diagnosed with irritable bowel syndrome. Then they go on with their life trying to manage their symptoms with different diets, supplements and herbal medicine.

blastocystis infection natural treatment herbal treatment how to naturally treat blastocystis

In a past article we reviewed a paper
in which the patient, diagnosed with IBS, suffered from chronic gut issues for 27 years. Finally a small intestinal bacteria breath test was ordered and came back positive. Did the patient have IBS or simply SIBO posing as IBS?There has been a push to find the link between IBS and gut infections including Blastocystis infection (1) and SIBO (2) for quite some time. As irritable bowel syndrome is considered a diagnosis of exclusion I think it is incredibly important to exclude all other possibilities before diagnosing IBS. See here for everything I’ve published on IBS

Does the Blastocystis parasite infection Explain The Lab Findings

Let’s start with the standard blood work and move on from there

Mean Corpuscular (Cell) Volume

Mean corpuscular volume, or MCV, is a marker found on a standard full blood examination. Often functional medicine practitioners like to jump into the more complex (and expensive) labs. I’m certainly not against this when it’s warranted, but the standard (and vastly less expensive) blood work markers can hint at where we need to look next. MCV is one of many great examples of this point. It represents the size of your red blood cells. When it is out of the reference range on the low side it indicates microcytic (small) red blood cells and generally points to iron deficiency anaemia. On the high side we are seeing macrocytic cells, too large, indicating a lack of the required nutrients to make a cell the proper size. Here we start to suspect either B12 or B9 deficiency (3).

In our case we see a normal marker of MCV but it is edging on the high normal side. Most doctors would look at that as normal and without any other information it would be. Looking at it from a functional or nutritional lens we start to suspect some possible issues on the horizon. Still we need to look a bit deeper before we jump to conclusions.

Mean Corpuscular (Cell) Haemoglobin

This measures the average weight of haemoglobin in each red blood cell. Here we can see a very high normal. Again still within the reference ranges, and even in the optimal ranges but getting pretty close to out of the lab ranges. High measurements (as in out of the lab reference range) of this most likely indicate B12 and B9 deficiencies (4). Again here we can’t jump to any conclusions, but it is starting to paint a picture.

mean corpuscular volume mean haemoglobin volume B12 deficiency megaloblastic anaemia

Normal Serum B12 Findings

Here is where it gets interesting. The serum B12 marker was within the normal reference ranges. Does this mean that the other markers were off? Doubtful.

Serum B12 is not the most accurate of markers when assessing the B12 status. That is where some more specialised testing is required to rule in or rule out B12 deficiencies. As both B12 and B9 are essential for making and maturing different blood cells it is important to know what their levels actually are. Here we can look active B12, known as holotranscobalamin, the active form of B12. Homocysteine levels can help paint the picture as well as methylmalonic acid (5).

Low Holotranscobalamin

Holotranscobalamin, aka active vitamin B12, is the fraction of B12 that is attached to the protein transcobalamin. In this form it can be delivered to cells throughout the body, hence the name ‘active’. One interesting study looked at levels of holotranscobalamin compared to serum B12, methylmalonic acid and homocysteine. They concluded that holotranscobalamin was a good first pass when looking to include or exclude vitamin B12 deficiencies but noted that certain biomarkers, like creatinine, had to be taken into account (6). In this case study we can see levels of holotranscobalamin below the reference range, indicating B12 deficiency.

vitamin B12 deficiency blastocystis hominis

High Homocysteine

Looking now to homocysteine we can see high levels. This is an interesting marker. Again homocysteine helps to paint the picture. Unfortunately it doesn’t tell us anything concrete or specific.

high homocysteine vitamin B12 deficiency vegetarian vegan

Haemoglobin Levels

To wrap up the blood work assessment we can see normal levels of haemoglobin (Hb on the lab below) and normal levels of red blood cells (RCC on the lab below). This indicates that B12 deficient anaemia, also known as megaloblastic anaemia, is most likely not occurring (yet)  

mean corpuscular volume mean haemoglobin volume B12 deficiency megaloblastic anaemia

Discussing The Findings

There are so many different things to address here. Why proper testing is crucial, the importance of functional reference ranges (without being overly zealous) and the possible impact that Blastocystis infections may have on digestion and absorption of different nutrients.

Standard of care blood tests can tell us so much about how the body is functioning. Many Functional Medicine advocates recommend in-depth and expensive testing to get to the bottom of the health problem. Personally I have no real objection to this if it is within reason and indicated. That said, I do feel the basic blood tests can really help to paint a picture of health and disease and guide the health care provider when considering what other tests may be needed. Looking at our case study we see a late 20’s male, fit and healthy with a high quality diet (although starting to minimise his meat intake) and mild gastrointestinal complaints. His blood work, while generally normal, showed low active B12 and high homocysteine and a positive for the parasite Blastocystis hominis.

There are three overarching treatment considerations here. Number one would be to bring the patient’s B12 markers back into a healthy range by supplementation. As his folate markers were good this should bring his homocysteine levels back into a healthy range. If it doesn’t then it is important to find and address why his homocysteine levels are higher than they should be.

The second consideration is getting to the bottom of why his vitamin B12 markers are low.

Blastocystis hominis is a prevalent gastrointestinal parasite. Conventional thinking hasn’t established it as pathogenic but a personal history with this particular bug and the dozens of different cases I’ve encountered here in Byron Bay lead me to see it as a problem in many people. Whether or not Blastocystis hominis is impacting the patient’s digestion and absorption of vitamin B12, a herbal antimicrobial treatment seems indicated. It is not uncommon for iron deficiency and/or B12 to accompany Blastocystis hominis infections but it hasn’t been established yet whether Blastocystis itself causes these deficiencies or if it is a preexisting deficiency (7).

Note – This is an important update in my thinking on parasite infections including Blastocystis infections. At the moment I have changed my thinking around treatment approaches. For the past few years I approached these gut infections with zero tolerance, as in you aren’t done treating until you have cleared the infection. After years of herbal antimicrobials I finally managed to clear the bug. Now I can see that may have been too hard a line to walk. Currently I approach it just a bit differently, mainly based on patient symptoms. If the herbal antimicrobials, probiotics and prebiotics have helped and you are symptom free I would consider the treatment plan finished. If your symptoms flare up again (maybe after going off track with your healthy diet for awhile) then herbal antimicrobials may be necessary again. Constantly bombing the gut with antimicrobial compounds is, in my opinion, a recipe for disaster and in many cases doesn’t clear the parasite infection. Don’t ignore your symptoms. In this case a herbal antimicrobial approach for 45 days, some probiotics and B12 supplementation may be just what is needed, whether we clear the Blastocystis infection or not.

Other factors that may or may not be playing a role

  • The patient has been experimenting on and off with a vegetarian diet.
  • He may be suffering from low stomach acid production which is necessary for B12 digestion and absorption (8) – Here we would want to look at other important markers like zinc

This is not an article trashing vegetarian or vegan diets but I do think it is important to mention the possible nutrient deficiencies seen in diets that lack animal products, particularly vitamin B12. Now this doesn’t mean you need to eat animal products to get B12 but it would be wise to supplement if you aren’t already doing so.

One interesting study looked at the differences in B12 status between omnivores, lacto-vegetarians and vegans. Using the more sensitive marker, holotranscobalamin, they found low vitamin B12 status in people not supplementing with vitamins in 11% of omnivores, 77% of lacto-vegetarians, and 92% of vegans. They found a similar pattern of elevated homocysteine in the groups as well.

The authors concluded with an important point on B12 deficiency. ‘The depletion process may take years to become clinically evident. Early diagnosis of vitamin B12 deficiency is crucial, owing to the latent nature of this disorder and the resulting possible irreversible neurological damage’

What To Address & When

There are other issues that may be at play in this particular case so it is important to have a treatment plan that helps remedy the patient’s primary complaint of gastrointestinal upset, replenish any vitamin or mineral deficiencies presented in the lab findings and look for the root cause. In terms of his primary complaint of flatulence, bloating and heaviness in the stomach there are a number of helpful herbal medicines that are indicated.

Carminative herbs help to relieve flatulence and bloating and can act as a smooth muscle tonic, relaxing or tonifying if needed. Popular carminatives that are widely used include

  • Fennel seeds
  • Peppermint (avoid this one if you have GERD/GORD)
  • Angelica
  • Chamomile

A herbalist would look at the heaviness after meals as a big sign of poor digestive function. Here herbal medicine really shines. Bitter herbs help to stimulate digestion. They ramp up digestive juices, stimulate the release of digestive enzymes from the pancreas and can facilitate the manufacture of bile in the liver and it’s release from the gallbladder. I have noticed that this symphony of digestion can become thrown off track quite easily for a number of reasons. In this case the disrupted gut flora may be the root cause. Bitter herbal medicines that stand out in this particular case include

  • Gentian – the queen of bitters
  • Myrrh – has antimicrobial actions as well
  • Dandelion root – stimulates the release of bile from the gallbladder as well
  • Barberry – also stimulates bile production in the liver and is antimicrobial too
  • Globe artichoke – stimulates bile in the liver and protects and repairs the liver

B12 injections were recommended by the patient’s primary practitioner. A wise move. Monitoring his status is important.

Finally addressing his parasite infection is important as this may be the root cause of his symptoms and B12 deficiency. Blastocystis hominis can be reasonably hard to treat. I have seen a few dozen cases, here in Byron Bay, that have not responded to frontline antibiotic therapy at all. Herbal medicines can be effective, but as in my case, may take a number of rounds to completely clear the infection.

A summary of herbal medicines that help with Blastocystis infections include

  • Goldenseal
  • Barberry
  • Coptis chinensis
  • Wormwood
  • Black Walnut
  • Garlic
  • Cat’s Claw

Now over to you. Have you experienced any of the symptoms in this particular case? If so share what helped and what didn’t in the comments below.

References and Resources

  1. New Insights into Blastocystis spp.: A Potential Link with Irritable Bowel Syndrome
  2. Irritable bowel syndrome and small intestinal bacterial overgrowth: meaningful association or unnecessary hype.
  3. Blood results in clinical practice
  4. Blood chemistry and CBC analysis
  5. Megaloblastic Anemia and Other Causes of Macrocytosis
  6. Holotranscobalamin – a first choice assay for diagnosing early vitamin B12 deficiency?
  7. Integrative Management of Blastocystis Hominis Enteritis
  8. Vitamin B12 in Health and Disease
  9. Vitamin B-12 status, particularly holotranscobalamin II and methylmalonic acid concentrations, and hyperhomocysteinemia in vegetarians
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  1. I have all the symptoms for irritable bowl, plus ulcers ? soooo much bloating! I’ve also had the helicobactor Pylori bug in the past! I’m really questioning my gut even more now after your post. Fascinating read, that really spoke to me in many ways. So well written too ????

      1. Hello, I have that parasite several years ago and I have gastrointestinal problems, chronic fatigue and now I have iron deficiency, if anyone knows of an effective treatment let me know

  2. Hi Todd, nice work that you’re doing! Thank you for sharing your knowledge, this is of great help and understanding to me.
    For a lot of time now I’ve been trying to piece together my own protocol for eradicating my infection with what I think is blasto. The thing is that I am convinced I’d found the remedy for the infection but due to lack of knowledge in how to mould it into a suitable protocol for me (taking in consideration the symptoms and complaints) I didn’t get yet to where I want to be. This because the substance I want(ed) to use is toxic (off course, otherwise it wouldn’t kill the parasite) but could be potentially dangerous for humans as well when taken in certain amounts. It deals with all stages in the life cycle of blasto. Where anti biotics tend to fail, due to being unsuccessful in killing off only the adult life stage of blasto, this substance is capable in ridding them all.
    But myself having trouble with adrenal fatigue/thyroid issues and lots of other thing that developed down the road as cause and affect, my immune system is weakened. Now not long ago I found a dietary supplement that contains the same ingredient that I wanted to use in the first place. It is made for parasitic infections in general and not targeted for a specific parasite species. I do not know what the amount or percentage of this compound is in 1 capsule, but I would hate when the blasto becomes immune to the treatment.
    I started this yesterday so it is too early to say something about the effect of it. But I’ve read here on your page about Coptis Chinensis, is this Berberine? I have a jar with Berberis Aristata tablets here, do you know if that is the same substance as Coptis Chinensis?
    Maybe I can start using it inbetween, on and off.
    I really want this to be over with as it as caused so much for so long now (10+ years)

  3. Hi Todd,
    I have Blastocystis and I am very iron deficient.
    Do you think it’s wise to supplement with iron, and get an iron infusion?
    As I’ve heard the parasite eats iron, and it can make the symptoms worse? Thanks

  4. Great article Todd. I live in the U. S. So nice to see someone go into blastocystis from a natural/alternative health perspective. Mainstream Western simply calls it a commensal and non-pathogenic which over a billion people have, yada, yada…

    I feel blasto must have some specific subtypes that are pathogenic and they have not been properly studied. (Of course this whole issue is clouded with our earth being systemically bombarded and saturated with various co-factor toxins).

    In my case, I have a long history of blasto and endolomax nana, both found 10 years apart through testing with Great Smokey Labs (Genova). I’ve had a rare form of non-iron anemia since then.

    Numerous other complications in my case but no matter, all for the highest good.

    Anyway, long journey, and constant vigilance needed. Blessings on the journey mate.

    1. Hi Michael,

      Thanks for the great comments! I think the story on blastocystis is still being worked out. The subtype angle is still confused with some research showing subtype pathogenicity while others showing it is more strain related than subtype. For the most part I assess the ecosystem and if anything is out of balance we work on correcting that first before going after blastocystis specifically. I think another article is in the near future 🙂

      All the best with your healing journey. As long as you are making steps forward you are winning!



  5. Hello Todd
    Concerning the treatment of difficult parasitic infections like Blasto….Do you have a CONTACT in the U.S. in your field of herbal expertise treating parasite infections/SIBO….My blood lab results show I also have iron issues ( very low #) ?…I know I have parasite issues but am negative about finding the right functional practitioner/diagnosis & treatment….Happy New Year…

    1. find licensed naturopathic doctors in the US, they are trained in botanical medicine and use evidence-based medicine when applying it! Hope it helps you!

  6. Glad I found this read from over here in NZ ! For about 5. Years I had incredible tummy pains , until one day a doctor found I had Blasto. I was given antibiotics and seemed to come right , until 5 years later when I had issues again, but more so with bloating and digestive issues . I’ve been struggling for 4 years , and recently found out I had blasto again (or did it never leave, and instead came back more aggressively?) .

    I was offered antibiotics again , but turned it down as I don’t want to flare up again in another 5 years (+I’ve been given so many antibiotics over these 4 years as doctors never new what was wrong) . I’m starting the Candida diet , and have natural supplements to try and get rid of this parasite! I have added some of your suggestions into my list to try . I have also struggled with low iron (anemic) and low B12 (doctors couldn’t figure out why I had low B12) . Thanks for the info ! 🙂

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