Dientamoeba fragilis is an infection which occurs very rearly in humans. It is not an ameba but a flagellate. This protozoan parasite produces trophozoites which is a cysts have not been identified. Infection may be either symptomatic or asymptomatic.The trophozoites are generally between 9-15 m in diameter and contain one or two nuclei. The nuclear chromatin is usually fragmented. There is no cyst stage. D. fragilis are best detected in permanent -stained fecal smears. The complete life cycle of this parasite has not yet been determined, but assumptions were made based on clinical data. To date, the cyst stage has not been identified in D. fragilis life cycle, and the trophozoite is the only stage found in stools of infected individuals.

Causes

A small amoeba that is parasitic in the large intestine and is capable of causing low-grade inflammation coupled with mucous diarrhea and gastrointestinal disturbance. Though dientamoeba fragilisthe ability of to cause disease is still questioned by some, the circumstantial evidence incriminating this organism as a pathogen is overwhelming. People who live in institutions that have poor sanitary conditions and travelers who visit developing countries have the highest risk for the infection of dientamoeba.

Infection might be spread by :-

Accidentally swallowing pinworm eggs (which might protect this fragile parasite) or the eggs of other parasite.
Swallowing something, such as water or food, or touching (and bringing your fingers to your mouth) something contaminated with stool from someone infected with D. fragilis.

Symptoms

Due to its frequent concurrence with other parasites, symptoms may not be caused by Dientamoeba alone and further research is needed to determine transmission and the possibility that it may be a commensal.Dientamoeba fragilis signs may refer to those signs only noticable by a doctor :-

Loose stools
Diarrhea
Abdominal cramping
Weight loss
Loss of appetite
Abdominal tenderness
Fatigue

Treatment

For the best treatment doctor will ask you to provide stool samples for testing. Because the parasite is not always found in every stool sample, you might be asked to submit stool samples from more than one day. You might also be tested for pinworm eggs, which are commonly (but not always) found in persons infected with D. fragilis.
Safe and effective drugs are available. The drug of choice is iodoquinol. Paromomycin, tetracycline, (contraindicated in children under age 8, pregnant and lactating women) or metronidazole can also be used.
Metronidazole, Tetracycline and Iodoquinol are all conventional drugs, that may be used in the treatment of Dientamoeba fragilis.