Establishment of Animal Infection Model of Spirometra Mansoni and Identification of Spirometra Mansoni by Enzyme-Linked Immunosorbent Assay.

Objective: Spirometra mansoni is a crucial zoonotic parasite. Its larvae are more harmful than adult worms due to their ability to migrate through the host's tissues and organs. Therefore, it is necessary to establish an animal model of spargana for observing pathological changes and exploring diagnostic techniques. Methods: In this study, we infected Kunming mice and cats without any pathogens by feeding sparganum (with the scolex and neck) in order to understand the infection cycle of S. mansoni and explore the preservation host of sparganosis. The infection of S. mansoni was determined by fecal detection and enzyme-linked immunosorbent assay (ELISA). Results: In the model of cats, the eggs of S. mansoni were found in the feces ten days after the infection. The serum-specific IgG antibodies against S. mansoni were positive in experimental groups (mice and cats), and after sixty days, the S. mansoni worms isolated from experimental groups were collected. Conclusion: In conclusion, the experimental results show that mice and cats can be stably infected with S. mansoni through feeding sparganum (with the scolex and neck). The infection method of this study has the potential to establish a practical model for investigating the diagnostic process of S. mansoni, laying the groundwork for application and development. ELISA was used to diagnose mice and cats infected with sparganosis mansoni, providing a case for non-invasive identification of animal sparganosis.

Important nutrient sources and carbohydrate metabolism patterns in the growth and development of spargana.

BACKGROUND: Sparganosis is a worldwide food-borne parasitic disease caused by spargana infection, which infects the muscle of frogs and snakes as well as many tissues and organs in humans. There are currently no viable treatments for sparganosis. Understanding spargana's nutrition source and carbohydrate metabolism may be crucial for identifying its energy supply and establishing methods of treatment for sparganosis. METHODS: Using an amino acid analyzer and nutrient concentration detection kits, we assessed nutrient concentrations in the muscles of Fejervarya limnocharis and Pelophylax plancyi infected or not infected with spargana. Quantitative polymerase chain reaction (PCR) was used to quantify the major enzymes involved in five glucose metabolism pathways of spargana developing in vivo. We also used quantitative PCR to assess key enzymes and transcriptome sequencing to explore the regulation of carbohydrate metabolic pathways in vitro in response to different 24-h food treatments. RESULTS: Infected muscle tissues had considerably higher concentrations of glucogenic and/or ketogenic amino acids, glucose, and glycogen than non-infected muscle tissues. We discovered that the number of differentially expressed genes in Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis was larger in low-glucose than in other dietary groups. We examined differences in the expression of genes producing amino acid transporters, glucose transporters, and cathepsins in spargana grown in various nutritional environments. In the normal saline group, only the major enzymes in the tricarboxylic acid cycle (TCA), glycogenesis, and glycogenolysis pathways were expressed. The L-glutamine group had the greatest transcriptional levels of critical rate-limiting enzymes of gluconeogenesis and glycogenesis. Furthermore, the low-glucose group had the highest transcriptional levels of critical rate-limiting enzymes involved in the TCA, glycolytic, and glycogenolysis pathways. Surprisingly, when compared to the in vitro culturing groups, spargana developing in vivo exhibited higher expression of these critical rate-limiting enzymes in these pathways, with the exception of the pentose phosphate pathway. CONCLUSIONS: Spargana have a variety of nutritional sources, and there is a close relationship between nutrients and the carbohydrate metabolism pathways. It takes a multi-site approach to block nutrient absorption and carbohydrate metabolism pathways to provide energy to kill them.

Cestodiasis in 2 Puerto Rican crested anoles.

Two adult male Puerto Rican crested anoles (Anolis cristatellus cristatellus) housed in a research facility were presented with debilitation and were euthanized. On autopsy, anole 1 had a large cystic white structure in the left pelvic limb, which protruded through the ruptured epidermis, and a large, poorly demarcated swelling in the right caudal abdomen. Anole 2 had masses in the mid-dorsum, caudal dorsum, left pelvic limb, and tail. These masses contained variably sized cestode larvae, which ruptured into the coelomic cavity. Evaluation of the larvae revealed a thickened and wrinkled anterior end, with a cleft-like invagination, consistent with either a plerocercoid sparganum or a tetrathyridium. Histologically, several cestode larvae were contained in the body wall of both anoles. These were up to 650 µm in diameter, with a thin tegument and a spongy parenchyma. The spongy parenchyma contained numerous, up to 30 µm diameter, sharply demarcated, basophilic-to-black structures (calcareous corpuscles). There was pneumonia and hepatitis in anole 2, suggestive of potential secondary infection subsequent to immunosuppression. Molecular amplification of the cytochrome C oxidase subunit 1 revealed 100% homology for the COX1 gene of the diphyllobothriid tapeworm Spirometra erinaceieuropaei, also known as Spirometra mansoni.

Molecular identification of sparganum of Spirometra mansoni isolated from the abdominal cavity of a domestic cat in Vietnam.

Cats normally play a role of the definitive host in which the plerocercoid (sparganum), the second larval form of Spirometra spp., develops into an adult in the intestines. However, some cases of cats with visceral or subcutaneous sparganosis were sporadically reported worldwide. We herein documented the discovery of a sparganum in abdominal cavity of a domestic cat during a surgery of dystocia. The larva was molecularly identified as Spirometra mansoni, belonging to Type I, that was recently misidentified to be S. erinaceieuropaei in several Asian countries. This is the first report for sparganum of S. mansoni in the cat. The future study is necessary to provide further insights into the species of Spirometra causing sparganosis and spirometrosis in humans and other animals.

Hand palm sparganosis: morphologically and genetically confirmed Spirometra erinaceieuropaei in a fourteen-year-old girl, Egypt.

Two spargana of 5 and 7 cm long were removed from the right-hand palm of 14-year-old girl at the General Hospital, Qalyubia, Egypt. Sparganum is the 2nd larval stage (pleurocercoid) of Diphyllobothrid cestode species develops in the vertebrate second intermediate host through ingestion of the crustacean first intermediate host.Dogs and cats are the final hosts get infected through predation of the second vertebrate host.Human attracts infection through drinking water contaminated with the infected crustacean host or consumption of the flesh of of vertebrate hosts such as frogs and reptilian species. The surgically removed specimens were parsitologically identified as a non-proliferative metacestodes of a spirometran species that then on molecular analysis proved to be Spirometra erinaceieuropaei. The present report has allocated Egypt on the world sparganosis map.Molecular characterization of 28 S rRNA of S. erinaceieuropae and correlation to other Spirometra spp. from the Nile countries, particularly Ethiopia and Lake Victoria countries where the Nile waters originate, and from China were dealt with. Drinking of contaminated fresh water is the only proposed mode of infection in Egypt.

[Establishment of an animal model of Sparganum mansoni infection and study on therapeutic methods II Establishment of a mouse model of sparganosis mansoni via oral administration of procercoids].

OBJECTIVE: To establish an animal model of sparganosis mansoni through oral administration of Cyclops infected with procercoids. METHODS: Domestic cats were infected with Sparganum mansoni under laboratory conditions, and fresh cat stool samples were collected, washed in dechlorinated water, and filtered. Spirometra mansoni eggs were collected and prepared into suspensions. Twenty C57BL/6j mice were randomly divided into the experimental group (n = 15) and the control group (n = 5). Wild Cyclops were infected with Spirometra mansoni coracidia to allow 3 to 5 procercoids in each Cyclop. Then, each mouse in the experimental group was given 15 Cyclops infected with procercoids by gavage, while mice in the control group were orally administered with the same volume of dechlorinated water. All mice were sacrificed after 5 months, and dissected, and suspicious Sparganum mansoni worms were collected. The serum specific IgG antibody against Sparganum mansoni was measured in mice using enzyme-linked immunosorbent assay (ELISA). Genomic DNA was isolated from suspicious Sparganum mansoni worms, and the specific Sparganum mansoni cytochrome oxidase I (COI) gene was amplified using PCR assay. RESULTS: Among the 15 mice in the experimental group, six were positive for the serum specific IgG antibody against Sparganum mansoni, and milky white worms were found and collected from the subcutaneous regions of 4 out of 6 mice. Only one worm was detected in each mouse, and the worm morphology was similar to Sparganum mansoni. Capillary electrophoresis of the PCR amplification products of COI gene presented a specific band with 151 bp in size, and sequencing analysis revealed 100% homology with Sparganum mansoni. CONCLUSIONS: A mouse model of sparganosis mansoni is successfully created through oral administration of Cyclops infected with Spirometra mansoni procercoids.

Epidemiology, Diagnosis, and Prevention of Sparganosis in Asia.

Sparganosis is a zoonotic parasitic disease caused by the larvae (spargana) of the genus Spirometra, which is widely distributed globally and threatens human health. More than 60 species of Spirometra have already been identified, and over 2000 cases have been reported. This review summarizes the prevalence of humans, frogs, snakes, and other animals with spargana. Furthermore, the infection mode, distribution, and site are summarized and analyzed. We also describe the epidemiology, molecular diagnosis, and other aspects which are of considerable significance to preventing sparganum.

Epidemiology and Genetic Diversity of Spirometra Tapeworm Isolates from Snakes in Hunan Province, China.

Sparganosis, caused by the plerocercoid larvae of Spirometra tapeworms, is a public health hazard worldwide. The prevalence and genetics of sparganum from snakes remain unclear. In this study, we investigated the prevalence of sparganum infection in wild snakes in Hunan province and compared the prevalence of Spirometra tapeworms in snakes worldwide. Furthermore, the genetic diversity of collected isolates was analyzed using mitochondrial cytb and cox1 genes. The result shows that the sparganum infection rate in wild snakes (89.50%, 402/449) was higher in Hunan than in other regions. Genetic diversity analysis based on concatenated sequences revealed high genetic diversity but no distinct genetic structure among Spirometra populations. Phylogenetic analysis supported the division of European and Chinese Spirometra isolates and a single species in Chinese Spirometra isolates. The prevalence of Spirometra tapeworms in snakes is serious, and the risk of sparganosis should be further publicized.

Prevalence of sparganum infection in wild frogs in Hainan province of China involves a risk for sparganosis.

BACKGROUND: Sparganosis is a serious parasitic zoonosis triggered by intake of and wound contact with frog flesh or the water infected or contaminated by sparganum. METHODS: The prevalence of Sparganum infection in wild frogs was assessed. A questionnaire survey was also conducted among the residents in Hainan Province to evaluate people's awareness of the medical and epidemiological relevance of sparganosis. RESULTS: A total of 1556 wild frogs were collected to examine Sparganum infection in different organs. A total of 201 (12.92%) were found to be infected with spargana of the genus Spirometra. There were 612 spargana found in those frogs, and the average infection rate was 3.04 per frog. The infection rate in the central region of Hainan Island is higher than that in other regions. Most spargana were found in the hind legs of frog, and the infection rate was not related to the weight of frogs. About 37.05% of the residents on Hainan Island have the knowledge of sparganosis and sparganum infection, and the internet was a major way to learn about sparganosis. The results of logistic regression analysis showed that occupation was identified as a determinant of sparganosis knowledge, and gender, age and residence were the most important risk factors for sparganosis. These results indicated that sparganum infection in wild frogs is common and is a potential threat to the residents on Hainan Island, and unhealthy lifestyle and eating habits may trigger sparganum infections. CONCLUSION: Wild frogs are commonly infected by Sparganum, which is a potential threat to people. To prevent sparganosis in humans, it is necessary to raise public awareness of sparganum infection in frogs and its association with sparganosis, as well as advocate healthy diet concepts and habits, and abandon the capture, sale and purchase of wild frogs to prevent and decrease the incidence of sparganosis.

A Case of Ocular Sparganosis in China: Episode of Migration from Muscle Cone to Subconjunctiva.

To improve our understanding of the migration of sparganum in humans, we report a case of ocular sparganosis having the migratory episode from the muscle cone to the subconjunctiva. A 34-year-old woman was admitted to the Hospital of Anhui Medical University (Hefei, China), in December 2019. She presented with conjunctival hemorrhage and recurrent pain in the left eye. A foreign body was found in the muscle cone of the eye. Two months later, a ribbon-like white material was found under the conjunctiva on slit-lamp examination. A long and slender, actively moving parasite was extracted by surgery. The extracted worm was approximately 8 cm long and 2 mm wide. The worm was whitish, wrinkled, ribbon shaped, and had a slightly enlarged scolex. The worm sample was morphologically identified as a plerocercoid larva (sparganum) of the Spirometra tapeworm. Her conjunctival blood suffusion and eye pain ceased within 1 week after operation. She has been in good health without any symptoms during the 2-year follow-up. A case of ocular sparganosis, in which larval worm migrated from the muscle cone to the subconjunctiva is reported from China.

[Construction of a cDNA library for Sparganum mansoni and screening of diagnostic antigen cadidates].

OBJECTIVE: To construct a cDNA library of Sparganum mansoni and immunoscreen antigen candidates for immunodiagnosis of sparganosis mansoni. METHODS: Total RNA was extracted from S. mansoni, and reversely transcribed into cDNA, which was ligated into the phage vector. These recombinant vectors were packaged in vitro to construct the SMART cDNA library of S. mansoni. Then, the cDNA library was immunoscreened with sera from patients with sparganosis mansoni to yield positive clones. The inserted fragments of positive clones were sequenced and subjected to homology analyses, and the structure and functions of the coding proteins were predicted. RESULTS: The SMATR cDNA library of S. mansoni was successfully constructed. The titer of the cDNA library was 6.25 × 106 pfu/mL, with a recombinant efficiency of 100%, and the mean length of the inserted fragments in the library was larger than 1 100 bp. A total of 12 positive clones were obtained by immunoscreening, and were categorized into Sm-I (Sm60-1), Sm-II (Sm58-1), Sm-III (Sm20-1) and Sm-IV (Sm22-3), with 1 134, 1 063, 883 bp and 969 bp long inserted fragments. Their coding proteins were highly homologous with the Spirometra erinaceieuropaei antigenic polypeptide, cytoplasmic antigen, ribosomal protein S4-like protein and unnamed protein product, respectively. CONCLUSIONS: A SMART cDNA library of S. mansoni has been successfully constructed and 4 categories of positive clones have been identified, which provides a basis for further studies on diagnostic antigens for sparganosis mansoni.

A Human Case of Lumbosacral Canal Sparganosis in China.

In this study, we intended to describe a human case of lumbosacral canal sparganosis in People's Republic of China (China). A 56-year-old man was admitted to Xiangya Hospital Central South University in Changsha, Hunan province, China after having an experience of perianal pain for a week. An enhancing mass, a tumor clinically suggested, was showed at the S1-S2 level of the lumbosacral spine by the examination of magnetic resonance imaging (MRI) with gadolinium contrast. The patient was received the laminectomy from S1 to S2, and an ivory-white living worm was detected in inferior margin of L5. In ELISA-test with cerebrospinal fluid (CSF) and serum samples, anti-sparganum antibodies were detected. He had a ingesting history of undercooked frog meat in his youth. By the present study, a human case of spinal sparganosis invaded in lumbosacral canal at the S1-S2 level was diagnosed in China. Although the surgical removal of larvae is known to be the best way of treatment for sparganosis, we administered the high-dosage of praziquantel, albendazole and dexamethasone to prevent the occurrence of another remain worms in this study.

First identification and molecular phylogeny of Sparganum proliferum from endangered felid (Panthera onca) and other wild definitive hosts in one of the regions with highest worldwide biodiversity.

After decades of being neglected, broad tapeworms now attract growing attention thanks to the increasing number of reports from humans but also thanks to many advancements achieved by application of molecular methods in diagnosis and epidemiological studies. Regarding sparganosis, unfortunately general uniformity of most species, their high intraspecific variability and lack of agreement among researchers has led to confusion about the classification of Spirometra/Sparganum species. For the first time we determined adult, eggs and plerocercoid life cycle stages and the molecular phylogeny of Sparganum proliferum obtained from endangered wild felids (Panthera onca, Leopardus pardalis, Leopardus guttulus and Herpailurus yagoauroundi) in one of the largest continuous remnants of worldwide biodiversity, the Atlantic Forest from South America. Our results showed that at least 57% of total species of wild felids in this natural area could act as definitive hosts of Sparganum proliferum. We conclude that the availability of more morphological characteristics are needed in order to secure reliable characterization and diagnosis of sparganosis. The integration of these data with molecular analysis of mitochondrial DNA sequences will be useful for species discrimination.

Larval Gnathostomes and Spargana in Chinese Edible Frogs, Hoplobatrachus rugulosus, from Myanmar: Potential Risk of Human Infection.

Chinese edible frogs, Hoplobatrachus rugulosus, were examined to estimate the potential risks of human gnathostomiasis and sparganosis in Myanmar. A total of 20 frogs were purchased in a local market of Yangon and examined with naked eyes and the artificial digestion method after skin peeling in June 2018 and June 2019. Larvae of gnathostomes and Spirometra (=spargana) were detected in 15 (75.0%) and 15 (75.0%) frogs with average intensities of 10.5 and 6.3 larvae per infected frog, respectively. Gnathostome larvae were 2.75-3.80 (av. 3.30) mm long and 0.29-0.36 (0.33) mm wide. They had a characteristic head bulb with 4 rows of hooklets, a muscular long esophagus, and 2 pairs of cervical sac. The mean number of hooklets were 41, 44, 47, and 50 on the 1st, 2nd, 3rd, and 4th row, respectively. Collected spargana were actively moving, particularly with the scolex part, and have ivory-white color and variable in size. Conclusively, it has been first confirmed that Chinese edible frogs, H. rugulosus, are highly infected with larval gnathostomes and spargana in this study. Consuming these frogs is considered a potential risk of human gnathostomiasis and sparganosis in Myanmar.

Human proliferative sparganosis update.

Proliferative sparganosis is one of the most bizarre and mysterious parasitic diseases ever described. The causative parasite is Sparganum proliferum, which is a pseudophyllidean cestode distinct from Spirometra tapeworms. Here we overview this rare but fascinating disease with the all original case reports on human patients published in the last 115 years. Proliferative sparganosis is clearly divided into two disease types, cutaneous and internal proliferative sparganosis. Cutaneous type starts with a skin eruption caused by the dermal invasion of a sparganum. Skin lesion progresses to larger areas of the body if left untreated. Various internal organs and body wall can be eventually affected. The clinical symptoms of patients in this group are very similar to each other. Molecular data suggest that cutaneous proliferative sparganosis is caused by S. proliferum of which genetic variation is limited, regardless of the time or localities of the emergence of patients. Internal proliferative sparganosis, on the other hand, is much more heterogeneous. Some cases show aggressive infection in internal organs, while others show only restricted lesions. Some of the cases that had been cited as proliferative sparganosis in the past literature were removed from the list, because they were judged as cyclophyllidean tapeworm infections. DNA sequencing is mandatory for the definite diagnosis of proliferative sparganosis. The Venezuelan strain of S. proliferum is maintained in experimental mice in Japan, which is fully prepared for the experimental study with advanced technologies in modern molecular biology.

Breast Sparganosis Presenting with a Painless Breast Lump: Report of Two Cases.

Sparganosis is a parasitic infestation caused by sparganum, a plerocercoid tapeworm larva of the genus Spirometra. Since the first case of human sparganosis reported in 1908, sparganosis has been a global disease, and is common in China, Japan, and Southeast Asian countries. Consumption of raw snakes, frogs, fish, or drinking contaminated beverages are sources of human infections. Human sparganosis usually manifests in subcutaneous fat in areas such as the abdomen, genitourinary tract, and limbs. Breast sparganosis cases are rare, representing less than 2% of total cases of human infections. Complete surgical extraction of the sparganum is the treatment of choice. Because of the rarity of the disease, clinical suspicion is vital to reach the diagnosis of breast sparganosis. Here we report 2 rare cases of breast sparganosis presenting with a painless breast lump, both treated with surgical excision and sparganum extraction.

Development of EST-derived microsatellite markers to investigate the population structure of sparganum - the causative agent of zoonotic sparganosis.

The plerocercoid (sparganum) of Spirometra erinaceieuropaei is the main aetiological agent of human sparganosis. To improve the current knowledge on S. erinaceieuropaei evolution, we performed multi-locus microsatellite typing of sparganum isolates from China for the first time. All available expressed sequence tag (EST) sequences for the Spirometra were downloaded from the GenBank. The identification and localization of microsatellites in ESTs was accomplished by MISA. Based on the selected microsatellites, the genetic structure of 64 sparganum isolates collected from 11 geographical locations in southwest China were investigated through principal component analysis, STRUCTURE analysis and neighbour-joining clustering. A total of 522 non-redundant ESTs containing 915 simple sequence repeats were identified from 12 481 ESTs screened. Five primer pairs were finally selected. Using these loci, a total of 12 alleles were detected in 64 sparganum isolates. Little variability was observed within each of geographical population, especially among isolates derived from Kunming of Yunnan (YN-KM) province. Both STRUCTURE analysis and the clustering analysis supported that two genotypes existed among the sparganum isolates from southwest China. In conclusion, five microsatellite markers were successfully developed, and sparganum population was observed to harbour low genetic variation, further investigation with deeper sampling was needed to elucidate the population structure.

Human Sparganosis in Korea.

BACKGROUND: Sparganosis is a larval cestodiasis caused by the plerocercoid of Spirometra spp. Since the first description of human sparganosis in 1924, several hundred cases have been reported in Korea. However, systematic approaches for literature surveys of Korean sparganosis have seldom appeared. METHODS: We searched publicly available databases such as PubMed, Research Information Sharing Service, and Korea Medical Citation Index with relevant Medical Subject Headings. RESULTS: At least 438 Korean sparganosis cases have been described from 1924 to 2015. Preoperative diagnosis has been significantly increased since the 1980s due to popularization of serological and imaging diagnostics. Cases were largely detected from fifth decades in general, but cerebral sparganosis was detected in relatively young age groups (third and fourth decades). Sparganosis was prevalent in men (75.9%). Consumption of frog/snake and drinking unfiltered water were found in 63.4% and 16.9% of patients, respectively. Most frequently affected sites were subcutaneous tissues (49.9%), followed by the central nervous system (36.2%). Involvements of visceral organs (7.6%), ocular regions (3.6%), and muscles (2.7%) were noticed. In women, breast sparganosis constituted a large proportion (34.2%). Sparganosis associated with immunocompromised patients has recently been reported. CONCLUSION: Sparganosis has been continuously reported in Korea during the past 90 years, although its incidence has decreased during the last 20 years. The disease is mostly characterized by subcutaneous nodule, but infection of the worm in vital organs often results in serious illness. Continuous awareness is warranted to monitor sparganosis occurrence and associated clinical consequences.

The first case of genetically confirmed sparganosis (Spirometra erinaceieuropaei) in European reptiles.

Sparganosis is a zoonosis caused by the spargana (larvae) of Spirometra sp. (Diphyllobothriidae). Reptiles are particularly important vectors for the transmission of this parasite in Asia; however, their role in sparganosis spread in European wildlife is unrecognized. We investigated the infection of reptiles with Spirometra sp. in NE Poland, where several mammalian hosts have been identified recently and in the past. Of the 59 dead reptiles, plerocercoids were found in two grass snakes (Natrix natrix) from the Bialowieza Primeval Forest (BPF). The Spirometra erinaceieuropaei species was genetically confirmed using the evolutionary conserved nuclear 18S rRNA gene, and then compared to GenBank deposits. The sequences were identical to previously investigated Spirometra sp. found in Eurasian badger and wild boar from BPF. Our finding is the first genetically confirmed record of Spirometra sp. in reptiles in Europe. Since reptiles are often a component of mammalian diet, they can be a source of Spirometra tapeworm infection in European wildlife; however, further studies are needed to investigate the prevalence of infection in reptiles and other non-mammalian hosts.

Subcutaneous Sparganosis of the Breast.

A 77-year-old African American woman presented to the dermatologist with two pruritic lumps in her right breast. She reported traveling to Mexico on a cruise ship two years prior to the onset of her lesions, but denied a history of previous breast masses or malignancy. Despite former radiographic evaluation by her internist revealing benign growths, and despite dermatologic treatment with intralesional steroid injections, a third new, firm nodule developed in her right breast. One such nodule eventually formed into an ulcer, and a punch biopsy revealed thin-walled vascular channels in loose inflamed stroma, coarse fibrosis, calcareous corpuscles, and an elongated parasite. Further review confirmed the parasite to be Sparganum, which is the larval stage of cestodes in the genus Spirometra. Sparganosis is a rare parasitic infection caused by the plerocercoid larva of the diphyllobothroid tapeworm. Though subcutaneous sparganosis of the breast is exceedingly rare, clinicians should consider this infection in their differential of nodular breast masses.