Blastocystis hominis (B. hominis) is a unicellular protozoan found in the large intestine of humans. B. hominis is the most prevalent single-celled eukaryotic organism found in humans. It is a causative pathogen in irritable bowel disorders and the toxins released by B. hominis can contribute to fibromyalgia. This presence of B. hominis-specific immunoglobulins in the serum samples suggests that the immune action against this parasite is not limited to the intestinal level. Antibodies to the pathogen can be found in both symptomatic and asymptomatic individuals, therefore, it is still unclear whether B. hominis is a truly pathogenic organism, or a commensal, or perhaps, is capable of being a pathogen in specific circumstances.
Blastocystis hominis
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