title: Gorillas are a host for Dientamoeba fragilis: an update on the life cycle and host distribution.
abstract: Dientamoeba fragilis is a gastrointestinal protozoan that has a worldwide distribution and is emergeing as a common cause of diarrhea. As D. fragilis has a propensity to cause chronic illness with symptoms similar to irritable bowel syndrome (IBS) it is not surprising that some patients with D. fragilis are misdiagnosed as having IBS. In contrast to most other pathogenic protozoa very little is known about its life cycle, epidemiology and mode of transmission. What role animal reservoirs play in the transmission of this parasite is unknown. Consequently we undertook a prospective study to determine the host distribution of D. fragilis. Over a 2-year-period, 608 faecal samples from a wide range of animal and bird species, including pigs and other food species, were screened using permanent stained smears for the presence of D. fragilis. Trophozoites of D. fragilis were only detected in Western lowland gorillas (3/10) (Gorilla g. gorilla) and confirmed by PCR targeting the SSU rRNA gene. The limited host range detected suggests human infection may not involve transmission from other animal species. In addition, we provide an update on the limited knowledge about the life cycle of this parasite and its host distribution.
authors.affiliation: St Vincent's Hospital, Division of Microbiology, SydPath, Darlinghurst, NSW, Australia. dstark@stvincents.com.au
authors.forename: Damien
authors.initials: D
authors.lastname: Stark
authors.forename: Owen
authors.initials: O
authors.lastname: Phillips
authors.forename: Donna
authors.initials: D
authors.lastname: Peckett
authors.forename: Ursula
authors.initials: U
authors.lastname: Munro
authors.forename: Deborah
authors.initials: D
authors.lastname: Marriott
authors.forename: John
authors.initials: J
authors.lastname: Harkness
authors.forename: John
authors.initials: J
authors.lastname: Ellis
mesh_terms: D000818:Animals; D018420:Ape Diseases / Q000453:epidemiology / Q000469:parasitology* / Q000635:transmission; D016054:DNA, Protozoan / Q000032:analysis; D003937:Diagnosis, Differential; D004029:Dientamoeba / Q000302:isolation & purification*; D004030:Dientamoebiasis / Q000453:epidemiology / Q000469:parasitology / Q000635:transmission / Q000662:veterinary*; D004197:Disease Reservoirs / Q000662:veterinary; D005243:Feces / Q000469:parasitology; D006071:Gorilla gorilla / Q000469:parasitology*; D006790:Host-Parasite Interactions; D006801:Humans; D007411:Intestinal Diseases, Parasitic / Q000175:diagnosis / Q000469:parasitology / Q000662:veterinary; D043183:Irritable Bowel Syndrome / Q000175:diagnosis; D008018:Life Cycle Stages; D016133:Polymerase Chain Reaction / Q000379:methods / Q000662:veterinary; D011446:Prospective Studies; D013045:Species Specificity
chemical_list: D016054:DNA, Protozoan