Human infection with the pancreas fluke, Eurytrema pancreaticum

Characterization of the Complete Mitochondrial Genome and Phylogenetic Analyses of Eurytrema coelomaticum (Trematoda: Dicrocoeliidae)

Eurytrema coelomaticum, a pancreatic fluke, is recognized as a causative agent of substantial economic losses in ruminants. This infection, commonly referred to as eurytrematosis, is a significant concern due to its detrimental impact on livestock production. However, there is a paucity of knowledge regarding the mitochondrial genome of E. coelomaticum. In this study, we performed the initial sequencing of the complete mitochondrial genome of E. coelomaticum. Our findings unveiled that the mitochondrial genome of E. coelomaticum spans a length of 15,831 bp and consists of 12 protein-coding genes, 22 tRNA genes, two rRNA genes, and two noncoding regions. The A+T content constituted 62.49% of the genome. Moreover, all 12 protein-coding genes of E. coelomaticum exhibit the same arrangement as those of E. pancreaticum and other published species belonging to the family Dicrocoeliidae. The presence of a short string of additional amino acids (approximately 20~23 aa) at the N-terminal of the cox1 protein in both E. coelomaticum and E. pancreaticum mitochondrial genomes has contributed to the elongation of the cox1 gene in genus Eurytrema, surpassing that of all previously sequenced Dicrocoeliidae. The phylogenetic analysis displayed a close relationship between E. coelomaticum and E. pancreaticum, along with a genus-level association between Eurytrema and Lyperosomum. These findings underscore the importance of mitochondrial genomic data for comparative studies of Dicrocoeliidae and even Digenea, offering valuable DNA markers for future investigations in the systematic, epidemiological, and population genetic studies of this parasite and other digenean trematodes.

Pathological findings of bovine pancreatic lesions induced by Eurytrema pancreticum in Aceh cattle, Sumatra

Great losses of cattle and other ruminants due to Eurytrema pancreaticum have been recorded in Indonesia and other countries in Southeast Asia. The objective of this study was to examine histological alterations after E. pancreaticum infection in cattle. This study analysed the pathological changes of pancreas in 153 cattle sampled randomly at slaughterhouses in Banda Aceh, Indonesia. Samples were obtained during one year as part of routine meat inspection. The samples of cattle pancreas were obtained from slaughterhouse in Banda Aceh and examined for eurytrematosis. The number of infected pancreases was 64 out of 153 (41.8%). The pancreases indicated some alterations including macroscopic colour changes of the pancreatic capsular surface, followed by the production of mucus on the surface. Some adult flukes were found in the capsular surface of the pancreas together with fluke eggs. The dissected pancreases were prepared for histopathological study for each segment, and then observed under microscope. The implications of findings from histopathologic analyses of the pancreas are discussed.

Discovery of Eurytrema Eggs in Sediment from a Colonial Period Latrine in Taiwan

In this study we take a closer look at the diseases that afflicted Japanese police officers who were stationed in a remote mountainous region of Taiwan from 1921 to 1944. Samples were taken from the latrine at the Huabanuo police outpost, and analyzed for the eggs of intestinal parasites, using microscopy and ELISA. The eggs of Eurytrema sp., (possibly E. pancreaticum), whipworm and roundworm were shown to be present. True infection with Eurytrema would indicate that the policemen ate uncooked grasshoppers and crickets infected with the parasite. However, false parasitism might also occur if the policemen ate the uncooked intestines of infected cattle, and the Eurytrema eggs passed through the human intestines. These findings provide an insight into the diet and health of the Japanese colonists in Taiwan nearly a century ago.

A case of human pancreatic eurytremiasis

This study provides the first comprehensive imaging report of human pancreatic eurytremiasis. A 43-year-old man with obstructive jaundice and a pancreatic tumor was referred for diagnosis and treatment. Serum aspartate aminotransferase, alanine aminotransferase, and gamma-glutamyl transpeptidase were elevated. Computed tomography (CT) revealed a multilocular cystic lesion with delayed enhanced area in the pancreas head. On magnetic resonance imaging, the tumor was hyperintense on diffusion-weighted image, and the apparent diffusion coefficient value of the tumor was lower than that of the normal pancreatic parenchyma. Positron emission tomography with 2-deoxy-2-[fluorine-18]fluoro-D-glucose integrated with computed tomography (¹⁸F-FDG PET/CT) revealed abnormally increased uptake of ¹⁸F-FDG in the tumor. A subtotal stomach-preserving pancreaticoduodenectomy was performed on the preoperative diagnosis of pancreatic carcinoma accompanied by branch duct-type intraductal papillary mucinous neoplasm. Multifocal granulomatous lesions with necrotic areas including many parasite eggs were seen on the histology. The final diagnosis was pancreatic eurytremiasis.

Helminths of veterinary and zoonotic importance in Nigerian ruminants: a 46-year meta-analysis (1970-2016) of their prevalence and distribution

BACKGROUND

The livestock industry plays a vital role in the economy of Nigeria. It serves as a major source of income and livelihood for majority of Nigerians who are rural settlers and contributes about 5.2% to the National Gross Domestic Product (GDP). Helminths however, cause economic losses due to reductions in milk production, weight gain, fertility and carcass quality. Zoonotic helminths of livestock origin cause health problems in humans.

METHODS

Using the Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) guidelines, the prevalence and distribution of helminths of veterinary and zoonotic importance in Nigerian ruminants were determined in a meta-analysis of data published between 1970 and 2016. Data were stratified based on regions, hosts, study periods, sample sizes and study types while helminths were phylogenetically grouped into cestodes, nematodes and trematodes.

RESULTS

Data from 44 studies reported across 19 Nigerian states revealed an overall pooled prevalence estimate (PPE) of 7.48% (95% CI: 7.38-7.57) for helminths of veterinary and zoonotic importance from a total of 320 208 ruminants. We observed a significant variation (P < 0.001) between the PPEs range of 1.90% (95% CI: 1.78-2.02) and 60.98% (95% CI: 58.37-63.55) reported across different strata. High heterogeneity (99.78, 95% CI: 7.38-7.57) was observed. Strongyloides papillosus was the most prevalent (Prev: 32.02%, 95% CI: 31.01-33.11), while, Fasciola gigantica had the widest geographical distribution.

CONCLUSIONS

Helminths of veterinary and zoonotic importance are prevalent in ruminants and well distributed across Nigeria. Our findings show that helminths of ruminants may also be possible causes of morbidity in humans and economic losses in the livestock industry in Nigeria. High heterogeneity was observed within studies and the different strata. Good agricultural practices on farms, standard veterinary meat inspection and adequate hygiene and sanitation in abattoirs, farms and livestock markets need to be implemented in Nigeria in order to reduce the economic, public health and veterinary threats due to these helminths.

Helminths of zoonotic importance in slaughtered food animals in Nigeria: a systematic review and meta-analysis

Knowledge of endemic helminths in a resource-limited country such as Nigeria is essential for their diagnosis, treatment and cost-effective control. In the present study, the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analysis) guideline was employed to determine the prevalence and geographical distribution of zoonotic helminths in food animals slaughtered in Nigerian abattoirs between 1970 and 2016. Pooled prevalence estimate (PPE) was determined by the random-effects model while heterogeneity was evaluated using the Cochran's Q-test. Results from 42 eligible studies reported across 19 Nigerian states revealed 85,466 cases of zoonotic helminths from 3,771,832 slaughtered food animals. Overall PPE was 2.27% (95% confidence interval (CI): 2.25, 2.28). PPEs for sub-groups ranged between 0.51% (95% CI: 0.46, 0.56) and 18.05% (95% CI: 17.12, 19.01) across regions, hosts, study periods and diagnostic methods. Ascaris suum had the highest pooled prevalence of 25.46% (95% CI: 24.04, 26.92). Overall prevalence estimates for cestodes, nematodes and trematodes were 0.60% (95% CI: 0.59, 0.61), 21.51% (95% CI: 20.73, 22.30) and 1.86% (95% CI: 1.84, 1.87), respectively. A high degree of heterogeneity 99.97% (95% CI: 2.25, 2.28, P: 0.000) was observed. Zoonotic helminths were prevalent in slaughtered food animals, with higher prevalence estimates in the north-central region, pigs and during the last decade reviewed. Ascaris suum was the most prevalent helminth, while Fasciola gigantica had the widest geographical distribution. It is envisaged that the present information will help in the formulation of disease-control policies, encourage on-farm good agricultural practices, and adequate hygiene and sanitation in abattoirs and meat-processing plants, with the aim of protecting public health.

Current status and its epidemiological consideration of Fasciola and Eurytrema infections in beef cattle of Japan

To elucidate current status of fasciolosis and eurytremosis in beef cattle of Japan, inspection data of Tokyo Metropolitan Shibaura Slaughterhouse where beef cattle were shipped from all over Japan were analyzed, and questionnaire to farmers was conducted to assess the relationship between recognition of the disease occurrence in one’s own farm and attention to the diseases. The occurrence of fasciolosis and eurytremosis in beef cattle gradually decreased from 18.6% to 0.06% and from 0.58% to 0.02% during the period of 1964 to 2010, respectively. When the current data from 2009 to 2012 were analyzed, the occurrence of fasciolosis was recognized in cattle produced and fattened all over Japan, indicating the disease was prevalent nationwide. While, 97.5% of Eurytrema infection were detected in cattle produced in Okinawa, Shimane and Kagoshima, indicating the disease was endemic in these regions. Higher occurrence (>0.7%) of fasciolosis was observed in minor breeds, such as Japanese Shorthorn. Japanese Black showed 0.09% and 0.05% of occurrence for fasciolosis and eurytremosis, respectively, but F1 crossbred with Japanese Black showed lower occurrence (0.007% and 0.002%, respectively). No tendency of occurrence in the age of cattle at slaughter was recognized, indicating the infections may have occurred at the growing and early fattening stage of cattle. The questionnaire survey revealed that farmers experiencing fasciolosis had more knowledge about the disease, however, factors, such as testing parasite infections and use of anti-Fasciola dewormers, were not affected by the recognition of occurrence.

De novo assembly and characterization of the transcriptome of the pancreatic fluke Eurytrema pancreaticum (trematoda: Dicrocoeliidae) using Illumina paired-end sequencing

Eurytrema pancreaticum is one of the most common trematodes living in the pancreatic and bile ducts of ruminants and also occasionally infects humans, causing eurytremiasis. In spite of its economic and medical importance, very little is known about the genomic resources of this parasite. Herein, we performed de novo sequencing, assembly and characterization of the transcriptome of adult E. pancreaticum. Approximately 36.4 million high-quality clean reads were obtained, and the length of the transcript contigs ranged from 66 to 19,968 nt with mean length of 479 nt and N50 length of 1094 nt, and then 23,573 unigenes were assembled. Of these unigenes, 15,353 (65.1%) were annotated by blast searches against the NCBI non-redundant protein database. Among these, 15,267 (64.8%), 2732 (11.6%) and 10,354 (43.9%) of the unigenes had significant similarity with proteins in the NR, NT and Swiss-Prot databases, respectively. 5510 (23.4%) and 4567 (19.4%) unigenes were assigned to GO and COG, respectively. 8886 (37.7%) unigenes were identified and mapped onto 254 pathways in the KEGG Pathway database. Furthermore, we found that 105 (1.18%) unigenes were related to pancreatic secretion and 61 (0.7%) to pancreatic cancer. The present study represents the first transcriptome of any members of the family Dicrocoeliidae, which has little genomic information available in the public databases. The novel transcriptome of E. pancreaticum should provide a useful resource for designing new strategies against pancreatic flukes and other trematodes of human and animal health significance.

Molecular characterization of Eurytrema coelomaticum in cattle from Paraná, Brazil

This study investigated the occurrence of Eurytrema spp. in cattle by analysis of the partial 18S rRNA gene sequence. Trematodes from 44 bovine pancreas were collected and classified based on typical morphological features. PCR assay and sequence analyses of amplified products confirmed that the trematodes classified as Eurytrema coelomaticum were phylogenetically distinct from those identified as E. pancreaticum. The results of this study represent the first molecular characterization of E. coelomaticum within the Americas, and provide an efficient method to differentiate digenean trematodes of domestic animals.

Trematodes recovered in the small intestine of stray cats in the Republic of Korea

In 2005, we reported the infection status of 438 stray cats with various species of intestinal helminths, including nematodes (4 species), trematodes (23 species), and cestodes (5 species) in the Republic of Korea. However, morphologic details of each helminth species have not been provided. In the present study, we intended to describe morphologic details of 13 trematode species which were either new fauna of cats (10 species) or new fauna of not only cats but also all animal hosts (3 species). The worms were fixed in 10% neutral buffered formalin under a cover slip pressure, stained with Semichon's acetocarmine, and then observed using a light microscope equipped with a micrometer. The 13 subjected species included members of the Heterophyidae (Stellantchasmus falcatus, Stictodora fuscata, Stictodora lari, Centrocestus armatus, Procerovum varium, and Cryptocotyle concava), Echinostomatidae (Echinostoma hortense, Echinostoma revolutum, Echinochasmus japonicus, and Stephanoprora sp.), Diplostomidae (Neodiplostomum seoulense), Plagiorchiidae (Plagiorchis muris), and Dicrocoeliidae (Eurytrema pancreaticum). By the present study, Cryptocotyle sp. and Neodiplostomum sp. recored in our previous study were identified as C. concava and N. seoulense, respectively. Three species, P. varium, C. concava, and Stephanoprora sp., are new trematode fauna in Korea.

Identification and characterization of microRNAs in the pancreatic fluke Eurytrema pancreaticum

Background

Eurytrema pancreaticum is one of the most common flukes, which mainly infects ruminants globally and infects human beings accidentally; causing eurytremiasis that has high veterinary and economic importance. MicroRNAs (miRNAs) are small non-coding RNAs and are now considered as a key mechanism of gene regulation at the post-transcription level.

Methods

We investigated the global miRNA expression profile of E. pancreaticum adults using next-generation sequencing technology combined with real-time quantitative PCR.

Results

By using the genome of the closely-related species Schistosoma japonicum as reference, we obtained 27 miRNA candidates out of 16.45 million raw sequencing reads, with 13 of them found as known miRNAs in S. japonicum and/or S. mansoni, and the remaining 14 miRNAs were considered as novel. Five out of the 13 known miRNAs coming from one family named as sja-miR-2, including family members from miR-2a to miR-2e. Targets of 19 miRNAs were successfully predicated out of the 17401 mRNA and EST non-redundant sequences of S. japonicum. It was found that a significant high number of targets were related to “chch domain-containing protein mitochondrial precursor” (n = 29), “small subunit ribosomal protein s30e” (n = 21), and “insulin-induced gene 1 protein” (n = 9). Besides, “egg protein cp3842” (n = 2), “fumarate hydratase” (n = 2), “ubiquitin-conjugating enzyme” (n = 2), and “sperm-associated antigen 6” (n = 1) were also found as targets of the miRNAs of E. pancreaticum.

Conclusions

The present study represents the first global characterization of E. pancreaticum miRNAs, which provides novel resources for a better understanding of the parasite, which, in turn, has implications for the effective control of the disease it causes.

Wasting and mortality in beef cattle parasitized by Eurytrema coelomaticum in the State of Paraná, southern Brazil

A sporadic wasting syndrome affecting beef cattle herds parasitized by Eurytrema coelomaticum is described in the State of Paraná, southern Brazil. The disease was characterized by progressive weight loss, poor body condition despite plenty of good quality forage available, and death. Annual losses ranged from 1 to 3%. The clinical course of the disease varied from 2 to 10 months after the onset of the first clinical signs. At necropsy, one of the three distinct following patterns of lesions were observed: the pancreas was of normal size and color; small, shrunken, white and markedly and diffusely firm (fibrosis); or slightly enlarged and dark with a shriveled capsular surface. Myriads of leaf-shaped trematodes of the genus Eurytrema were packed inside multiple dilated ducts with thickened, whitish fibrous walls, or the flukes were embedded in the remaining pancreatic parenchyma. Microscopic findings included extensive loss of the pancreatic parenchyma with replacement fibrosis, intralesional flukes and eggs, and ductal hyperplasia. Inflammatory reaction varied from absent to severe with the presence of a granulomatous reaction around the trematode eggs. One affected animal had high plasma amylase concentration (1580U/L) suggesting exocrine pancreatic insufficiency. Glucose blood levels were not significantly increased. We suggest that diffuse and marked fibrosis of the pancreas induced by the presence of large amounts of pancreatic flukes is the cause of the sporadic cases of chronic wasting and death of cattle in this geographic area.

Eurytrema pancreaticum: the in vitro effect of praziquantel and triclabendazole on the adult fluke

The efficacy and tolerance of the 80 microg/ml praziquantel (PZQ) and 40 microg/ml triclabendazole (TCZ) against adult stage Eurytrema pancreaticum in vitro were investigated at 3, 12, and 15 h incubation. Motility of the flukes and histopathological changes were studied. Sudden paralysis and death were observed after exposed to PZQ as early as 3h incubation. In contrast, the TCZ treated flukes showed active mobility at all intervals. By light microscopic examination, severe damages in various organs such as tegument, muscle, and testes were observed early at 12h incubation of these drugs. PZQ caused more severe damage to flukes than TCZ. There were vigorous contraction of musculature, progressive shrinkage of circular and longitudinal muscles, vacuolization and disintegration of the tegument disrupting the worms' outer surface including detachment of spines in the PZQ treatment. The cells in testes were slightly increased in size and followed by degeneration leaving several hollow spaces. The uterus and vitelline glands remained unaffected. The direct observation of the fluke motility and light microscopic study highly suggested that PZQ was more effective than TCZ treatment for the eurytremiasis infection.