Trichomonas gypaetinii n. sp., a new trichomonad from the upper gastrointestinal tract of scavenging birds of prey.

In the context of an epidemiological study carried out by several wildlife recovery centers in Spain, trichomonads resembling Trichomonas gallinae were found in the oropharyngeal cavity of 2 Egyptian vultures (Neophron percnopterus) and 14 cinereous vultures (Aegypius monachus) which did not show any symptoms of trichomonosis. In order to characterize them, these isolates along with seven other T. gallinae isolates obtained from different hosts and from different geographical origin were analyzed. Genetic analyses were performed by sequencing the small subunit ribosomal RNA (SSU-rRNA) and the internal transcribed spacers (ITS1 and ITS2) and the 5.8S rRNA regions. The morphological study of the isolates in both light and scanning electron microscopy was also performed. The sequences obtained in the genetic analysis coincide with previously published sequences of an isolate named as Trichomonas sp., obtained from a bearded vulture (Gypaetus barbatus), and showed clear differences to the T. gallinae sequences (97 and 90-91% homology, respectively, for SSU-rRNA and ITS regions) and display higher similarity with Trichomonas vaginalis and Trichomonas stableri than with T. gallinae. Multivariate statistical analysis of the morphometric study also reveals significant differences between the trichomonads of vultures and the isolates of T. gallinae. The isolates from vultures presented smaller values for each variable except for the length of axostyle projection, which was higher. These results together with the different nature of their hosts suggest the possibility of a new species of trichomonad which we hereby name Trichomonas gypaetinii, whose main host are birds of the subfamily Gypaetinae.

Compounds of the upper gastrointestinal tract induce rapid and efficient excystation of Entamoeba invadens.

The infective stage of Entamoeba parasites is an encysted form. This stage can be readily generated in vitro, which has allowed identification of stimuli that trigger the differentiation of the parasite trophozoite stage into the cyst stage. Studies of the second differentiation event, emergence of the parasite from the cyst upon infection of a host, have been hampered by the lack of an efficient means to excyst the parasite and complete the life cycle in vitro. We have determined that a combination of exposures to water, bicarbonate and bile induces rapid excystment of Entamoeba invadens cysts. The high efficiency of this method has allowed the visualization of the dynamics of the process by electron and confocal microscopy, and should permit the analysis of stage-specific gene expression and high-throughput screening of inhibitory compounds.

[The mucosal changes and influencing factors in upper gastrointestinal anisakiasis: analysis of 141 cases].

BACKGROUND/AIMS: Anisakiasis is a well known parasitosis resulted from eating raw seafoods and there were many reports of cases. However, its endoscopic and clinical characteristics have not been reviewed well. The aim of this study was to clarify the gastric mucosal changes and influencing factors of upper gastrointestinal (UGI) anisakiasis. METHODS: We analyzed retrospectively the endoscopic and clinical characteristics of 141 cases with UGI anisakiasis diagnosed during UGI endoscopy, based on the review of medical records. The patients' data were collected consecutively from October 1999 through September 2006. RESULTS: In the 141 patients with UGI anisakiasis, the peak age was the 40s (44.7%). The female to male ratio was 1.82:1. The most prevailed season was winter (41.1%). The most frequent symptom was acute epigastric pain and 76.6% of the patients developed symptoms within 12 hours after the ingestion of raw seafoods. The greater curvature of body was the most preferred site of anisakid larvae. The median time from meal to symptom onset was shortest in esophageal location and longest in fundus location (3 vs. 18.7 hours). The various mucosal changes were observed and the most frequent mucosal change was edema (90.8%). Submucosal tumor was also found in 31.9% of the patients. The severity of mucosal change was related inversely with the time interval from meal to endoscopy (p=0.048). CONCLUSIONS: Anisakiasis presented various mucosal changes depending on the time interval from ingestion of raw seafood to endoscopy. Delayed endoscopy may lead chronic mucosal change and cause difficulty in the detection of anisakiasis. Therefore, the prompt endoscopic examination is required for the patients presenting acute gastrointestinal symptoms after taking raw fish.

The Mucosal Changes and Influencing Factors in Upper Gastrointestinal Anisakiasis: Analysis of 141 Cases / 대한소화기학회지

BACKGROUND/AIMS: Anisakiasis is a well known parasitosis resulted from eating raw seafoods and there were many reports of cases. However, its endoscopic and clinical characteristics have not been reviewed well. The aim of this study was to clarify the gastric mucosal changes and influencing factors of upper gastrointestinal (UGI) anisakiasis. METHODS: We analyzed retrospectively the endoscopic and clinical characteristics of 141 cases with UGI anisakiasis diagnosed during UGI endoscopy, based on the review of medical records. The patients' data were collected consecutively from October 1999 through September 2006. RESULTS: In the 141 patients with UGI anisakiasis, the peak age was the 40s (44.7%). The female to male ratio was 1.82:1. The most prevailed season was winter (41.1%). The most frequent symptom was acute epigastric pain and 76.6% of the patients developed symptoms within 12 hours after the ingestion of raw seafoods. The greater curvature of body was the most preferred site of anisakid larvae. The median time from meal to symptom onset was shortest in esophageal location and longest in fundus location (3 vs. 18.7 hours). The various mucosal changes were observed and the most frequent mucosal change was edema (90.8%). Submucosal tumor was also found in 31.9% of the patients. The severity of mucosal change was related inversely with the time interval from meal to endoscopy (p=0.048). CONCLUSIONS: Anisakiasis presented various mucosal changes depending on the time interval from ingestion of raw seafood to endoscopy. Delayed endoscopy may lead chronic mucosal change and cause difficulty in the detection of anisakiasis. Therefore, the prompt endoscopic examination is required for the patients presenting acute gastrointestinal symptoms after taking raw fish.