Leaky Gut (Intestinal permeability):
This finding supports the view that Intestinal Permeability increases during the course of protozoan infections which cause damage to the intestinal wall while non-pathogenic protozoan infections have no effect on IP. The increase in IP in patients with B. hominis brings forth the idea that B. hominis can be a pathogenic protozoan.
Protozoon infections and intestinal permeability.
Dagci H, et al. Acta Trop 2002 Jan;81(1):1-5
Iron deficiency and B.hominis:
Iron deficiency anaemia (IDA) is a frequent health problem. Gut parasites such as N. americanus and A. duodenale are known to cause blood loss, but the role of Blastocystis hominis is uncertain. In this study, 212 patients (193 female, 19 male, mean age 41 SD 15 years) with IDA were enrolled and 90 persons without IDA (78 female, 12 male, mean age 45 SD 17 years). Microscopic examination of stools for B. hominis using the native lugol method was done three times on each subject. If any specimen contained five or more cysts per x400 field, the person was considered positive. B. hominis was found in 48 of 212 subjects with IDA (22.6%) and in 5 of 90 (5.6%) subjects without IDA. This difference is highly statistically significant (p<0.001). Few subjects had other gut parasites and there was no statistical difference in their frequencies between IDA and non-IDA subjects. Blastocystis hominis may play a role in the development of IDA either on its own or in conjunction with some other agent.
IS BLASTOCYSTIS HOMINIS A NEW ETIOLOGICAL FACTOR OR A COINCIDENCE IN IRON DEFICIENCY ANEMIA? Yavasoglu I et al. Adnan Menderes University Medical Faculty, Division of Hematology, Aydin, Turkey.
Blastocystis hominis found in stool specimens has been the most frequently identified parasite among foreign workers from Southeast Asia in Taiwan since 1992. The prevalence of B. hominis was 14.1% in this study. In their quarantine physical examinations, 121 male Thai workers were examined hematologically and screened for stool parasites using the merthiolate-iodine-formaldehyde concentration method. Hematological values were compared in workers with and without a B. hominis infection. Multiple regressions were used to adjust for age. Those infected with any parasite other than B. hominis were excluded from further analysis. The workers infected with B. hominis had a lower leukocyte count (6.5-0.4x103/wl) than those who were not (7.4-0.2x103/wl). This was mainly caused by a reduced neutrophil count (3.2-0.4 vs 4.2-0.2x103/wl). Hemoglobin (13.9-0.3 vs 14.5-0.1 g/dl) and hematocrit (41.4-0.6 vs 42.9-0.2%) were also reduced in B. hominis-positive workers.
Hematological effects of Blastocystis hominis infection in male foreign workers in Taiwan
H. S. Cheng, Y. L. Guo, J. W. Shin
Parasitology Research., Volume 90, Number 1 / May, 2003
B.hominis — growth in children:
"According to this study there is a correlation between the presence of B. hominis and lower anthropometric indexes in children."
The effect of Blastocystis hominis on the growth status of children.
Ertug S et al. Med Sci Monit. 2006 Dec 18;13(1):CR40-43
D.fragilis: Intestinal damage:
Preliminary observations indicate that the amebas do attach to the cecal mucosa and cause damage to the underlying cells.
The Neglected Ameba: Dientamoeba fragilis
Kean & Malloch, Am.J.of Dig. Dis., Vol 11, No. 9., 1966
The intestinal permeability was found to have increased in patients with protozoan infections compared with control patients (7.20+/-5.52 vs. 4.47+/-0.65%, P=0.0017). The IP values were 9.91+/-10.05% in Giardia intestinalis group, 6.81+/-2.25% in Blastocystis hominis group, 5.78+/-2.84% in Entamoeba coli group. In comparison with the control group, the IP was significantly higher in G. intestinalis and B. hominis patients (P=0.0025, P=0.00037, respectively), but not in E. coli patients. In conclusion, the IP increases in patients with G. intestinalis and B. hominis but not with E. coli infection. This finding supports the view that IP increases during the course of protozoan infections which cause damage to the intestinal wall while non-pathogenic protozoan infections have no effect on IP. The increase in IP in patients with B. hominis brings forth the idea that B. hominis can be a pathogenic protozoan.
Protozoon infections and intestinal permeability.
Dagci H, et al. Acta Trop 2002 Jan;81(1):1-5
The present study investigated the pathogenesis of Blastocystis hominis by intramuscular injection of the organism into experimental mice. A total of 27 naïve BALB/c mice aged 6-8 weeks were injected in the leg muscle with axenic culture isolate B of B. hominis. Histological examination at different times revealed that B. hominis could produce a severe inflammatory reaction and myonecrosis. Most changes were observed at 6 h after injection and for up to 2-3 days. By 2 weeks the muscle had regained normal histology. There was infiltration of polymorphonuclear leukocytes (PML) into the injection site, indicating that B. hominis had a strong chemoattractant activity for PML.
K. T. Moe et al. Cytopathic effect of Blastocystis hominis after intramuscular inoculation into laboratory mice. Parasitology Research. Volume 84, Number 6 / May, 1998; pages 450-454.
Impaired concentratation, depression, panic attacks, and other psychological disturbances are frequently reported to me by people infected with Bllastocystis hominis and/or Dientamoeba fragilis:
"My experiences have been similar to yours with Blastocystis hominis. At present I am able to work only half time. Perhaps more troubling than the fatigue is the brain fog. Ever since Peace Corps India 35 years ago, I have suffered recurrent bouts of various parasites, often in combination! I have never been tested for Dientamoeba fragilis. In fact, I only know about it from your website. "
Jan 02 - Specialised testing revealed an infection with B.hominis and D.fragilis.
"I felt vague, forgot words, felt extremely tired, weak and sick. Wierd head sensations were always present - felt foggy and unfocussed."
2001 - Recovered from B.hominis.
"My experiences have been similar to yours with Blastocystis hominis et al. At present I am able to work only half time. Perhaps more troubling than the fatigue is the brain fog.". Jan 02 - Diagnosed with B.hominis.
This 1992 study indicates that psychological symptoms are high in people with "unexplained gastrointestinal symptoms". When the study was published the majority of physicians considered Dientamoeba fragilis and Blastocystis hominis harmless. Because of this widely held view most people suffering symptoms described in this study did not have access to the specialised stool collection and testing methods essential to diagnose D.fragilis and B.hominis.
"When compared with those reporting no gastrointestinal symptoms, subjects who report at least one of these symptoms were significantly more likely to have also experienced lifetime episodes of major depression (7.5% vs 2.9%), panic disorder (2.5% vs 0.7%), or agoraphobia (10.0% vs 3.6%). Subjects with two gastrointestinal symptoms had even higher lifetime rates of depression (13.4%), panic (5.2%), or agoraphobia (17.8%). Lifetime rates of affective and anxiety disorders in the general population are higher in subjects with gastrointestinal symptoms compared with subjects without gastrointestinal symptoms. An even higher prevalence of affective and anxiety disorders is found in patients with medically unexplained gastrointestinal symptoms in tertiary-care clinics.
Comorbidity of gastrointestinal complaints, depression,
and anxiety in the Epidemiologic Catchment Area (ECA) Study. Walker EA, et al.
Am J Med 1992 Jan 24;92(1A):26S-30S.
When the parasite is eliminated the symptoms resolve:
"What I am most pleased about is that I have clarity of of mind and reduced gut pain. I am feeling optomistic, these past few days I haven't experienced brian fog or dizziness or long periods where I haven't been able to concentrate."
More examples here.
Vitamin & mineral deficiencies:
Studies show that magnesium levels are reduced in B.hominis patients. Low magnesium can lead to osteoporosis:
Magnesium levels were found to be clearly decreased (in B.hominis patients), whereas no change was observed in zinc levels in the patients with Blastocystis compared to controls.
Serum zinc and magnesium levels in patients with blastocystosis.
Kilic E , Yazar S , Saraymen R .
Biol Trace Elem Res. 2004 Apr;98(1):21-6.
Low dietary magnesium (Mg) may be a risk factor for osteoporosis
Dietary magnesium reduction to 25% of nutrient requirement disrupts bone and mineral metabolism in the rat. Rude, RK et al. Bone. 2005 Aug;37(2):211-9.
Relatively few animal studies have assessed the skeletal and hormonal impact of long-term low Mg intake; however, these studies have demonstrated that Mg deficiency results in bone loss.
Magnesium deficiency and osteoporosis: animal and human observations.
Rude RK , Gruber HE .
J Nutr Biochem. 2004 Dec;15(12):710-6.
More information about magnesium deficiency on Medline Plus.
The response of our patient to metronidazole therapy raises the possibility that other ulcerative colitis patients might benefit from this treatment and so postpone or avoid the need for major surgery. We would suggest the examination of stool specimens, looking specifically for this organism be performed routinely in ulcerative colitis patients with refractory symptoms.
Blastocystis hominis complicating ulcerative colitis. J.of the Royal Soc. of Med (Vol 84 Oct. 91)
A patient with persistent diarrhea was found to have biopsy-proved colitis with large numbers of the protozoan Blastocystis hominis present in stool. Extensive evaluation failed to reveal any other potential etiologic agent of acute colitis. Following treatment with a course of metronidazole, the patient became asymptomatic, B hominis was no longer present in stool, and results of a repeated biopsy were normal. These observations are consistent with the role of B hominis as a gastrointestinal pathogen.
Presumptive evidence for Blastocystis hominis as a cause of colitis.
Arch Intern Med 1988 May;148(5):1064
Clinical reports have suggested that Dientamoeba fragilis may be a cause of acute and chronic colitis in children and adults. The mechanism by which this parasite process produces colitis has not been determined. The clinical findings of this report suggest that D.fragilis causes colitis through an invasive ulcerating process.
Shein R. Gelb.A. Colitis due to dientamoeba fragilis. Am. J Gastroenterol. 1983; 78(10): 634-6
D Fragilis is thought to inhabit the mucosal crypts of the large intestine. Although it is considered to be non-invasive one case of colitis attributed to this organism has been reported .
Dientamoeba fragiis: a bowel pathogen? Robert Oxner et al. New Zealand Medical Journal. 11 Feb. 87
Dientamoeba fragilis is a rare cause of chronic infectious diarrhoea and colitis in children. Eosinophilic colitis documented by colonoscopy, was due to D. fragilis. Conclusion: D. fragilis should be included in the differential diagnosis of chronic diarrhoea and eosinophilic colitis.
Dientamoeba fragilis masquerading as allergic colitis. Cuffari C, Oligny L, Seidman EG Department of Pediatrics, Hopital Sainte-Justine, Universite de Montreal, Canada J Pediatr Gastroenterol Nutr 1998 Jan;26(1):16-20 . Eur J Pediatr 1997 Jul;156(7):583
We report a case of hemorrhagic proctosigmoiditis believed to be caused by B. hominis infection. This case provides further evidence to support the pathogenicity of B. hominis and that this organism should be considered a possible additional cause of hemorrhagic colitis in both immunocompetent and immunocompromised persons.
Hemorrhagic Proctosigmoiditis and Blastocystis hominis Infection [Letter] Carrascosa et al. Annals of Internal Medicine Volume 124(2) 15 January 1996 pp 278-279
Here B.hominis was diagnosed but, as is often the case, this sixteen year old's infection was not treated:
"Your site was very helpful to us for another reason however. Our 16 year old son who was perfectly well went to camp about a year ago and returned with bloody mucusy diarrhea. He eventually lost 30 pounds and had a lengthy hospitalization. WE TRULY BELIEVED IT WAS A PARASITIC SITUATION DUE TO ITS ABSOLUTE ABRUPT ONSET. Doctors were quick to diagnose Ulcerative colitis at great expense.". Jan 02
Parasites and arthritis:
A 46-year-old female patient developed a chronic diarrhea and oligoarthritis some days after returning from a trip to Senegal. Arthritis was refractory against treatment with NSAID and corticosteroids. Finally, a 3-week course of treatment with metronidazole resulted in a complete remission of arthritis, gastrointestinal symptoms, and inflammation signs (ESR, CRP). The course in our case, as well as the detection of Blastocysts hominis in synovial fluid in another case, implicate an infectious rather than a reactive etiology of arthritis.
Blastocystis hominis as a rare arthritogenic pathogen. Kruger K, et al. Z Rheumatol 1994 Mar-Apr;53(2):83-5
A patient with rheumatoid arthritis taking prednisone developed Blastocystis hominis acute diarrhea, which was associated with increased inflammation and effusion of the left knee. B hominis organisms were found in synovial fluid from the left knee. The patient responded dramatically to metronidazole treatment. B hominis may become disseminated in immunosuppressed patients with diarrhea and may cause infective arthritis.
Infective arthritis due to Blastocystis hominis.
Lee MG, Rawlins SC, Didier M, DeCeulaer K., Ann Rheum Dis 1990 Mar;49(3):192-3
Other published cases of arthritis:
Reactive arthritis from Blastocystis hominis. Arthritis Rheum 1991 Feb;34(2):251-3, Lakhanpal S, Cohen SB, Fleischmann RM.
It might be speculated that B.hominis downregulates the host immune responses in the early phase of the infection, in order to improve its survival. This seems to be a common evasion mechanism of parasites, as it has also been demonstrated for Toxoplasma gondii (Denney et al. 1999). Further it may also be expected that this effect of B.hominis could indirectly facilitate the progress of infection by other opportunistic pathogens. The results presented here indicate that B.hominis is able to induce and modulate the production of inflammatory cytokines in intestinal epithelial cells.
Blastocystis hominis modulates immune responses and cytokine release in colonic epithelial cells. H.Y. Long et al (Parasitology Res (2001) 87: 1029-1030)
Intestinal inflammation and Blastocystis hominis also described in:
The Occurrence of Blastocystis hominis in Intestinal Inflammation
(J. Am. Med. Assoc 1923 81:522-523)
The pathology of B. hominis infections has been studied in gnotobiotic guinea pigs in which inflammation of the intestinal mucosa and invasion of the superficial layers were seen. Only limited studies of human pathology are available. Those who have studied mucosal histopathology report inflammation and cellular changes that resolve after treatment.
Blastocystis hominis--past and future.
Zierdt CH. Clin Microbiol Rev 1991 Jan;4(1):61-79
"I've had numerous hospital procedures to be told that there appears an inflamed area of my bowel, but nothing could be detected. Instead I was diagnosed with a stress disorder and given tranquillisers for two years. During this time I had chronic fatigue, headaches, sore throats, chronic bowel pain and wind...yet the doctors prescribe me with more stress related chemicals." S pecialised stool testing revealed an infection with D.fragilis.
Feb 01. USA.
Blocked bowel & Blastocystis hominis - coincidence?
"...the little guy had a blocked bowel that went undiagnosed for two days. He didn't present with the usual symptoms. Now his mom is wondering if he had the infection prior to the bowel problem. As I have read through some of the stories it sounds a lot like the trouble he has had for the last year. Anyway ... By the time he got to the hospital (by ambulance), he was in rough shape. They operated on him and fixed the problem. No testing at that point assuming that his only problem was the bowel thing. He comes home on Friday. On Monday he is back in the hospital with diarrhea. At that point he is tested and the parasite (Blastocystis hominis) is detected . " (USA. 2003)
" I ended up in the hospital with a bowel blockage and when test results came back one of them detected the parasite blastocystis hominis "
(USA. Dec 2001)
After months of"nausea, fullness, bloating, intermittent diarrhea and constipation" a US woman was diagnosed with B.hominis. She was lucky to be diagnosed at all. A few weeks later another single, unfixed sample was negative. See the LabTesting for information about why specialised stool collection and testing methods are so essential to diagnosing B.hominis and D.fragilis. Because her second sample was negative she was not treated and she was diagnosed with Irritable Bowel Syndrome:
"I ended up in the hospital with a bowel blockage. My doctor put me on Dicetel for IBS and that made be far sicker than I was before I went on it. I had uncontrollable diarrhea, and the bloating was very uncomfortable. I now suffer from constipation, bloating and a feeling of fullness all the time, as well as some heartburn."
Allergic Skin Diseases:
Urticaria (hives) is a skin condition characterised by localised by swelling and raised red welts.
Angio-oedema is excessive swelling around the eyes or lips.
It is of interest to note that, like in the case presented here, the successful eradication of Blastocystis producing amoeboid forms during the cultivation period resulted in complete resolution of urticarial lesions (1, 7, 8, 15). This is the first report of acute urticaria associated with Blastocystis sp. subtype 3 amoeboid forms seen in culture. It appears helpful examining amoeboid forms of Blastocystis sp. in parasite cultures from unresponsive patients who have acute urticaria of unknown aetiology and minor gastrointestinal symptoms, in order to administer appropriate anti-parasite treatment. titular-bracket
Acute Urticaria Associated with Amoeboid Forms of Blastocystis sp. Subtype 3
Alexandra Katsarou-Katsari et al
Department of Dermatology, University of Athens
The prevalence of intestinal protozoans and helminths in stool samples of individuals with allergic cutaneous symptoms was evaluated to study a possible link between parasites and allergy. Altogether, 218 patients who had chronic urticaria, atopic dermatitis, or pruritus of unknown origin were included in the study. Standard laboratory tests for the detection of allergic etiology were performed for all patients. The presence of intestinal parasites was investigated using microscopy, immunofluorescence, and immunoenzymatic assays. Overall, protozoans and helminths were recovered from the stools of 48 subjects (P = 0.004), 18 of whom were affected with intestinal symptoms (P = 0.023). The presence of Giardia lamblia in the stools was significantly associated with allergic cutaneous manifestations (P = 0.030). In addition, patients with allergy were significantly more likely to have 5 Blastocystis hominis organisms per field (P = 0.046). There was a set of patients with allergic cutaneous diseases in whom the presence of intestinal parasites may not be incidental.
Prevalence of intestinal parasites among individuals with allergic skin diseaes.
Andrea Giacometti et al.
Institute of Infectious Diseases and Public Health, University of Ancona.
Journal of Parasitology. Article: pp.490-492
Urticaria and angioedema are easily recognized disorders, but in at least 70 percent of individuals, chronic episodes of urticaria are of unknown causes. We present 10 cases of chronic urticaria associated parasitation by Blastocystis hominis. This parasite has not been previously related with urticaria.
Urticaria by Blastocystis hominis. Armentia A, et al. Allergol Immunopathol (Madr) 1993 Jul-Aug;21(4):149-51
Remission of delayed pressure urticaria after eradication of Blastocystis hominis.
Acta Derm Venereol. Cassano N , Scoppio BM , Loviglio MC , Vena GA 2005;85(4):357-8.