Amoebic Parasites: Blastocystis Hominis, Dientamoeba Fragilis, Entamoeba Histolytica
Rarely tested for in UK hospitals. Not only contracted in poor hygiene countries.
What is Blastocystis Hominis and Dientamoeba Fragilis?
Blastocystis Hominis and Dientamoeba Fragilis are microscopic parasites which are discovered in the stools and can infect the digestive tract. Although 5% of the population have these parasites but are symptom-free, it is diagnosed in up to 20% of people who suffer with irritable bowel and/or chronic fatigue.
Symptoms of Blastocystis Hominis and Dientamoeba Fragilis
Many of those infected are carriers without any symptoms, the parasites simply reside in the digestive tract without causing any harm. However, these parasites can cause symptoms such as diarrhoea/constipation, mushy stools, nausea, abdominal pain, cramps, bloating and flatulence. Other less frequently reported symptoms include fever, bloody stools, vomiting, headache, itching, weight-loss, chronic fatigue, depression, and non-specific gastrointestinal symptoms. Many patients presenting with these symptoms are often for many years, misdiagnosed as suffering with irritable bowel syndrome (IBS).
How do you get Blastocystis Hominis or Dientamoeba Fragilis?
Blastocystis Hominis and Dientamoeba Fragilis are found throughout the world, although more common in less developed countries where hygiene and sanitation is not adequate. Its transmission is usually through the oro-feacal route. The risk of infection may increase through ingesting contaminated food or water and/or exposure to animals.
How can Blastocystis Hominis and Dientamoeba Fragilis be Diagnosed?
The detection of these parasites is difficult because they disintegrate promptly after they leave the intestine. Therefore, it is essential that the stool sample is placed immediately in a special fixative. In the UK there are only a few laboratories equipped to detect them, with more in Europe and the USA. The test is thorough. As these parasites are rather elusive, specialised laboratories recommend that three samples are taken for greater accuracy.
Treatment for Blastocystis Hominis and Dietamoeba Fragilis
A number of common antibiotics available in the UK are used for the treatment of BH, including Flagyl (metronidazole), Erythromycin or Doxycycline but these single drugs have a high failure rate. Some patients have also tried combinations of herbal remedies, including oil of oregano, black walnut, wormwood and so on, which are known to have significant effects on harmful micro-organisms. However, in our experience, the most successful treatment is the one developed by Professor Tom Borody at the Centre of Digestive Disorders (CDD) in Sydney, Australia. This is a combination of three or four medications. We also advise on how to safeguard a healthy gut, while taking the medication and after the treatment and how to deal with any side effects.
Can Blastocystis Hominis and Dientamoeba Fragilis be Cured?
Doctors are always reluctant to talk about “cures”. We recommend that, on completion of the course of treatment, a stool test is repeated. Our audits show that 80% of patients see a clearance of Blastocystis Hominis with the first course of treatment. Dientamoeba Fragilis is easier to eradicate and 90% of patients see a clearance with the first course. For some patients the parasites are resistant and the first course does not totally eradicate them. In this case a second or third course of various combinations of drugs are used. Subsequent treatments usually show a clearance of the parasites and resolution of the symptoms.
According to our audits, after eradication 70% of clients report various degrees of response or clearance of symptoms. 30%, despite the test results showing a clearance of the parasites, experience no changes to their symptoms. People with known food intolerance may underestimate its role in causing chronic abdominal symptoms, so The Burghwood Clinic believe it is important that this problem is also addressed.
How to Prevent Getting Blastocystis Hominis or Dientamoeba Fragilis
- Wash your hands with soap and warm water after using the toilet and before handling food.
- Teach children the importance of washing hands to prevent infection.
- Avoid water or food that may be contaminated.
- Wash and peel all raw vegetables and fruits before eating.
When traveling in countries where the water supply may be unsafe, only drink boiled tap water or canned or bottled carbonated drinks and make sure uncooked foods are washed with boiled tap water.
Why Medicine does not consider these amoebas pathogenic?
Whilst these parasites have been known for over a century, most of the earlier literature has described them as "commensals" i.e. harmless, incidental findings in stool cultures; not all carriers are symptomatic. However, in the last two decades a number of scientific papers published evidence that their eradication is often followed by a significant improvement or clearance of a range of abdominal symptoms, fatigue and other problems not directly related to the intestine.