Blastocystis hominis
From DrugPedia: A Wikipedia for Drug discovery
Blastocystis hominis
Blastocystis is a genus of single-celled protozoan parasites belonging to a group of organisms known as the Stramenopiles (also called Heterokonts) that includes algae, diatoms, and water molds. Blastocystis comprises several species, living in the gastrointestinal tracts of species as diverse as humans, farm animals, birds, rodents, reptiles, amphibians, fish, and cockroaches. The species residing in humans is known as Blastocystis hominis. Blastocystis hominis has a widespread geographic distribution and is common in countries of all income levels. Its status as a true pathogen is controversial – while it has been found in patients with gastrointestinal symptoms it is not proven to be the cause, and many carriers are asymptomatic. Research on Blastocystis hominis is limited, with large gaps remaining in our understanding of its life cycle, transmission mechanisms, incubation period, epidemiology, and treatment options.
| Kingdom | Chromalveolata |
|---|---|
| Phylum | Heterokontophyta |
| Class | Blastocystae |
| Order | Blastocystida |
| Family | Blastocystidae |
| Genus | Blastocystis |
| Species | B. hominis |
| Binomial | Blastocystis hominis |
[edit] Transmission
The precise transmission mechanisms of Blastocystis remain murky. Fecal-oral tansmission is the most accepted pathway, and recent studies have shown that transmission involves only the cyst form of the parasite. The extent to which human-human, human-animal, and animal-human transmission occurs is still unknown. Genomic studies provide evidence for all three routes, though experimental studies have yet to provide conclusive proof for the existence of either.
[edit] Pathogenic Activity
It is found in the stools of healthy people as well as in the stool of those who have diarrhea, abdominal pain or other gastrointestinal problems. However, it's not clear whether Blastocystis hominis actually causes an infection or if it simply resides in the digestive tract without causing harm.
