[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.

Surgical treatment of a patient with live intracranial sparganosis for 17 years.

BACKGROUND: The incidence of sparganosis, especially intracranial live sparganosis is very low in China. Due to the lack of typical clinical manifestations, it is difficult to make a clear preoperative diagnosis of the disease, which often leads to delays the disease and serious consequences. CASE PRESENTATION: A 23-year-old man presented with a 17-year history of intermittent seizures and right extremity numbness and weakness. Magnetic resonance imaging (MRI) showed patchy, nodular and line-like enhancement. Enzyme-linked immunosorbent assay (ELISA) detected positive antibodies to Spirometra mansoni in peripheral blood and cerebrospinal fluid (CSF). In addition, during the operation, an ivory-colored live sparganosis was removed under the precise positioning of neuronavigation, and the patient was diagnosed with cerebral sparganosis. The patient began praziquantel and sodium valproate treatment after the operation, and was followed up for 3 months. There was no recurrence of epilepsy, and the weakness and numbness of the right limb improved. CONCLUSION: Nonspecific clinical manifestations often make the diagnosis of cerebral sparganosis difficult, and a comprehensive diagnosis should be made based on epidemiological history, clinical manifestations, ELISA results and imaging findings. Surgery is the preferred method for the treatment of cerebral sparganosis, and more satisfactory results can be achieved under the precise positioning of neuronavigation.

First Clinical Cases of Spirometrosis in Two Cats in Korea.

This study reports the first two clinical cases of spirometrosis caused by Spirometra sp. in cats in Korea. In these two cases, the cats vomited, and long proglottids of tapeworm were recovered. The sick cats presented with anorexia and lethargy. However, they unexpectedly showed no diarrhea, which is the main symptom of spirometrosis. Based on a fecal floatation test as well as morphological and molecular analyses, the parasite was diagnosed as Spirometra sp. The 2 cases were treated with praziquantel. This study suggests regular monitoring of health and deworming in companion animals, even when animals are well cared for, with regular preventive medication. Additionally, spirometrosis should be considered in the differential diagnosis in cases of gastrointestinal symptoms in Spirometra endemic areas.

Recurrent eosinophilic pleuritis caused by sparganum infection: A case report and review of the literature.

RATIONALE: Sparganosis is an infectious disease caused by a larval tapeworm of the genus Spirometra, which commonly invades subcutaneous tissues. Pulmonary and pleural involvement due to sparganum has been rarely reported previously. PATIENT CONCERNS: We herein described a case of recurrent eosinophilic pleuritis in a 24-year-old woman. She was admitted with persistent cough and shortness of breath for more than 1 month. Initial chest computed tomography scan suggested right pleural effusion and diffuse pleural thickening. Slightly elevated eosinophil counts were found in both the peripheral blood and pleural fluid. She underwent right pleurectomy but histological examination failed to obtain an etiological diagnosis. Moreover, eosinophilic pleural effusion re-appeared in the contralateral thoracic cavity one month later. After re-admission, we reviewed her medical history meticulously and found she had a history of ingesting raw snake gallbladders before hospitalization. The final diagnosis was confirmed by the markedly positive reaction against sparganum antigen in both serum and pleural fluid sample. DIAGNOSIS: Eosinophilic pleuritis caused by sparganum infection. INTERVENTIONS: After the diagnosis, the patient was treated with praziquantel at 75 mg/kg/d for 3 days. OUTCOMES: Pleural effusion absorbed completely and eosinophil count in peripheral blood returned to normal range. No evidence of recurrent pleural effusion had been observed in over one year of follow-up. LESSONS: Clinicians need to be aware the possibility of sparganum infection in cases of eosinophilic pleuritis. The specific enzyme-linked immunosorbent assay remains a useful method in acquiring a rapid diagnosis, especially when histological examination is unable to detect the larvae in the thoracic cavity.

Cerebral sparganosis presenting with atypical postcontrast magnetic resonance imaging findings: a case report and literature review.

BACKGROUND: Sparganosis, a rare and severe parasitic infection caused by the larvae of Spirometra species or simply sparganum, generally involves subcutaneous tissue or muscle. But occasionally, sparganum can also invade the human brain, resulting in cerebral sparganosis. CASE PRESENTATION: A 33-year-old woman presented with a 10-day history of headache. Postcontrast magnetic resonance imaging (MRI) revealed an irregular lesion with enhancement and the tunnel-shaped focus extending to the contralateral hemiphere. Cerebrospinal fluid (CSF) analysis disclosed pleocytosis (166 cells/µL) and an elevated protein concentration (0.742 g/L). Enzyme-linked immunosorbent assay (ELISA) revealed positive sparganum-specific antibody in both blood and CSF. Finally, the diagnosis of cerebral sparganosis was comfirmed. She received praziquantel treatment and got a favorable outcome during six-month follow-up. CONCLUSIONS: Irregular enhancement and the tunnel sign that extends to the contralateral hemisphere on postconstrast MRI are unusual presentations of cerebral sparganosis. ELISA for sparganum-specific antibody can help confirm the diagnosis. Although surgery is the preferred treatment for cerebral sparganosis, praziquantel might also achieve satisfying outcomes.

A case report: 1-year follow-up of cerebral sparganosis mansoni with a stroke-like onset.

BACKGROUND: Sparganosis mansoni is a parasitic disease caused by infection with the larvae of Spirometra spp. tapeworms. Its clinical manifestations and severity depend on the migration and the location of the parasites. The proportion of cerebral sparganosis in all Spirometra mansoni infections is 13.5% in Thailand and 12.4% in China. In the clinical setting, cerebral sparganosis is often misdiagnosed due to atypical characteristics, irregular intracranial location, and atypical epidemiology. CASE PRESENTATION: The patient in the case study suffered from an acute paroxysmal attack of lateral numbness, accompanied with focal epilepsy. He was admitted to the neurology department as a stroke patient but was later diagnosed with cerebral sparganosis mansoni following lab and radiology investigations. He was fully recovered and free of Spirometra mansoni one year after initial consultation following several courses of oral praziquantel. The current report focuses on the diagnosis, treatment and follow up of this patient. CONCLUSIONS: A case of cerebral sparganosis mansoni with a stroke-like onsetsuggests that in the clinical diagnosis, neurologists should pay attention to brain lesions and look out for the possibility of neuroparasitic infections when dealing with patients with stroke-like onset accompanied by epilepsy. Detections of relevant antibodies in blood and cerebrospinal fluid may be necessary. The combination of the epidemiological history, clinical manifestations, detection of parasite antibody, head radiology, pathological biopsy, and identification of parasites will help us in diagnosis and differential diagnosis.

First report of sparganosis manifested by pleuritis and decreased peripheral blood eosinophils in Jiangsu province, China.

Sparganosis is a parasitic infection caused by the metacestode stage of Spirometra mansoni and some other related diphyllobothriidean cestodes. Although various internal organs were involved in sparganum infection, pulmonary and pleural involvement is rarely reported. We herein report an uncommon form of sparganosis manifested by pleuritis and decreased peripheral blood eosinophils. Sparganum worms were found in the pleural effusion accidentally and confirmed by pathological diagnosis. After being treated with praziquantel for 10 days, the patient's symptoms, laboratory examinations, and imaging findings were improved gradually.

Follow-up study of high-dose praziquantel therapy for cerebral sparganosis.

BACKGROUND: Cerebral sparganosis is the most serious complication of human sparganosis. Currently, there is no standard for the treatment of inoperable patients. Conventional-dose praziquantel therapy is the most reported treatment. However, the therapeutic outcomes are not very effective. High-dose praziquantel therapy is a useful therapeutic choice for many parasitic diseases that is well tolerated by patients, but it has not been sufficiently evaluated for cerebral sparganosis. This study aims to observe the prognoses following high-dose praziquantel therapy in inoperable patients and the roles of MRI and peripheral eosinophil absolute counts during follow-up. METHODOLOGY: Baseline and follow-up epidemiological, clinical, radiological and therapeutic data related to 10 inoperable patients with cerebral sparganosis that were treated with repeated courses of high-dose praziquantel therapy, with each course consisting of 25 mg/kg thrice daily for 10 days were assessed, followed by analyses of the prognoses, MRI findings and peripheral eosinophil absolute counts. PRINCIPAL FINDINGS: Baseline clinical data: the clinical symptoms recorded included seizures, hemiparesis, headache, vomiting and altered mental status. Peripheral blood eosinophilia was found in 3 patients. The baseline radiological findings were as follows. Motile lesions were observed in 10 patients, including aggregated ring-like enhancements, tunnel signs, serpiginous and irregular enhancements. Nine of the 10 patients had varying degrees of white matter degeneration, cortical atrophy and ipsilateral ventricle dilation. The follow-up clinical data were as follows. Clinical symptom relief was found in 8 patients, symptoms were eliminated in 1 patient, and symptoms showed no change from baseline in 1 patient. Peripheral blood eosinophilia was found in 2 patients. The follow-up radiological findings were as follows. Motile lesions that were transformed into stable, chronic lesions were found in 8 patients, and motile lesions that were eliminated completely were found in 2 patients. CONCLUSIONS: High-dose praziquantel therapy for cerebral sparganosis is effective. The radiological outcomes of motile lesions are an important indicator during the treatment process, especially during follow-ups after clinical symptoms have improved. Peripheral eosinophil absolute counts cannot be used as an effective prognostic indicator.

[Establishment of an animal model of Sparganum mansoni infection and study on therapeutic methods â Establishment of an animal model of Sparganum mansoni infection in mice and changes of serum specific antibody levels post-infection].

OBJECTIVE: To establish an animal model of Sparganum mansoni (plerocercoid larva of S. mansoni) infection in mice and observe the changes of blood routine examinations and serum anti-sparganum antibody levels after the infection. METHODS: The spargana tapeworms were collected from frogs, and 25 Kunming mice were orally infected with the Sparganum tapeworms (3 tapeworms/mouse). Two days before the infection and 2, 7, 14, 21, 28, 35, 42 days and 49 days after the infection, the peripheral blood samples of mice were collected for the blood routine examinations and the detections of anti-S. mansoni IgG antibody with ELISA. Forty-nine days after the infection, all the mice were sacrificed to find out the Sparganum tapeworms in the bodies of mice. RESULTS: The count of the total white blood cells was significantly elevated on the second day of the mice infected with Sparganum. The serum anti-Sparganum antibody was detected on the 14th day of the infection in some mice, and on the 21st day of the infection, the serum anti-Sparganum antibody was detected in all the mice. After the mice were sacrificed, the Sparganum tapeworms were found out in many tissues and organs, and especially in the subcutaneous tissues and muscle. CONCLUSIONS: The establishment of animal model of Sparganum infection is successful in mice with the oral method, and white blood cells and serum specific IgG antibody detection can be used as auxiliary diagnosis methods of S. mansoni infection.

Efficacy comparison between long-term high-dose praziquantel and surgical therapy for cerebral sparganosis: A multicenter retrospective cohort study.

BACKGROUND: Sparganosis is a parasitic infection caused by the plerocercoid larvae of Spirometra mansoni in East and Southeast Asia. The plerocercoid larvae sometimes invade the encephalon, resulting in severe cerebral sparganosis. Surgical removal of the larvae is considered a standard therapy for cerebral sparganosis. In contrast, the efficacy and safety of long-term, high-dose praziquantel treatment for cerebral sparganosis have not been explored. METHODOLOGY/PRINCIPAL FINDINGS: In this multicenter retrospective study, we assessed the records of 96 patients with cerebral sparganosis who consulted at three medical centers from 2013 to 2017. Forty-two patients underwent surgical lesion removal, and the other 54 patients received long-term, high-dose praziquantel (50 mg/kg/day for 10 days, repeated at monthly intervals). The primary outcome was the complete disappearance of active lesions on cerebral magnetic resonance imaging. The secondary outcomes included the modified Rankin scale score at 90 days, incidence of seizure, eosinophil count, and serological Spirometra. mansoni antibody titer. The efficacy of praziquantel treatment was similar to that of surgical lesion removal for cerebral sparganosis with respect to both the primary outcome and secondary outcomes. Although binary logistic regression models also supported the primary outcome after adjustment for age, sex, lesion location, and loss to follow-up, some unavoidable confounders might have biased the statistical power. No significant clinical complications or laboratory side effects occurred in the praziquantel group with the exception of a relatively benign allergic reaction. CONCLUSIONS/SIGNIFICANCE: In this small-sample, nonrandomized, retrospective exploratory study, some patients with cerebral sparganosis were responsive to long-term, high-dose praziquantel with an efficacy similar to that of surgical lesion removal. These findings increase the treatment flexibility for this serious infection.

Case report: the first case of human infection by adult of SPIROMETRA ERINACEIEUROPAEI in VIETNAM.

BACKGROUND: Tapeworms of the genus Spirometra include species whose larval stages can infect humans, causing a disease called sparganosis. Cases of human infection with adult worms are very rare and have been reported in Korea and China. Here we report the first case of human infection with an adult of Spirometra erinaceieuropaei in Vietnam. CASE PRESENTATION: A 23-year-old male was admitted to 103 Military Hospital, Hanoi, Vietnam with fever, weight loss and epigastric discomfort. Preliminary diagnosis based on discovery of parasite eggs in his faeces incorrectly determined a fluke as the agent of the infection and praziquantel was prescribed. Two days later he passed out proglottids in his stool. The tapeworm was identified as Spirometra erinaceieuropaei using morphological and molecular tools. CONCLUSION: This is the first case of human infection with adult worm of Spirometra erinaceieuropaei in Vietnam.

A neglected risk for sparganosis: eating live tadpoles in central China.

A 29-year-old farmer from central China was sent into the Emergency Department of the Affiliated Hospital of Zhengzhou University. He had a 15-day history of persistent high fever, abdominal distention and pain. The patient was clinically diagnosed as appendicitis and peritonitis, and treated with antibiotics in a local hospital, did not improve. On exploratory laparotomy, the appendicular perforation and peritonitis were seen; appendicectomy were performed, and antibiotics were given. However, high fever and abdominal pain still persisted; intestinal adhesion and obstruction, ascites appeared. He was given the "critically ill notice". He had eosinophilia (12.95%) and the history of eating live frog tadpoles for treating his cutaneous pruritus 3 days before onset of the disease. Serum anti-sparganum antibodies assayed by ELISA were positive. This patient has hospitalized for one and half months and spend more than US$ 12 000. This patient was primarily diagnosed as visceral sparganosis, and cured with praziquantel.Sparganosis is one neglected but important parasitic zoonosis of poverty. Human infections were mainly acquired by eating raw or uncooked meat of frogs and snakes infected with plerocercoids, using frog or snake flesh as poultices, or drinking raw water contaminated with infected copepods. However, sparganosis caused by ingestion of live tadpoles are emerging in central China. Our surveys showed that 11.93% of tadpoles in Henan province are infected with plerocercoids. Eating live tadpoles is a high risk for sparganum infection. The comprehensive public health education should be carried out for people in endemic areas and the bad habit of eating live tadpoles must be discouraged.

Clinical Features of Pulmonary Sparganosis.

BACKGROUND: Sparganosis is an infectious disease caused by the sparganum of Spirometra species, which seldom invades the respiratory system. The aim was to describe the clinical features and outcomes of pulmonary sparganosis. METHODS: A total of 40 patients with pulmonary sparganosis were reviewed, including 12 cases known from this experience and 28 cases reported in the literature. RESULTS: Among these 40 patients at an average age of 45.4 ± 11.1 years (men 29), 34 (85%) had a history of ingesting raw or undercooked meat (mainly frogs or snakes). The top 3 symptoms were coughing (60.0%), fever (57.5%) and chest pain (42.5%). Peripheral blood eosinophilia was found in 30 cases (75%). Lesions were located in lung parenchyma, airway, pleura and pulmonary vessels of the patients. Thirty-one patients (77.5%) had pleural effusion. The diagnosis was established by antisparganum antibody test in 30 cases (75%) and by pathology in 9 cases (22.5%); 1 case was not mentioned. Among the 35 cases with follow-up information, 2 treated with complete surgical removal and 31 with oral administration of praziquantel had no recurrence; the remaining 2 died without effective treatments. CONCLUSIONS: As an extremely rare and life-threatening parasitic zoonosis, pulmonary sparganosis should be diagnosed by combining the epidemiology, patient history, eosinophilia and the positive antisparganum antibody test result together if no worm was detected. Oral praziquantel is considered to be an effective treatment.

Human sparganosis, a neglected food borne zoonosis.

Human sparganosis is a food borne zoonosis caused by the plerocercoid larvae (spargana) of various diphyllobothroid tapeworms of the genus Spirometra. Human infections are acquired by ingesting the raw or undercooked meat of snakes or frogs, drinking untreated water, or using raw flesh in traditional poultices. More than 1600 cases of sparganosis have been documented worldwide, mostly in east and southeast Asia. Sporadic cases have been reported in South America, Europe, and Africa, and several cases have been described in travellers returning from endemic regions. Epidemiological data suggest that the increased effect of sparganosis on human health is because of greater consumption of raw meat of freshwater frogs and snakes. This Review provides information about the Spirometra parasites and their lifecycles, summarises clinical features, diagnosis, and treatment of human sparganosis, and describes geographical distribution and infection characteristics of Spirometra parasites in host animals.

An Unusual Cause of a Breast Mass in a Patient from China.

Sparganosis is a parasitic infection caused by Spirometra spp. and often presents as a subcutaneous swelling, most commonly noticed in the abdominal wall or extremities. Amphibians such as frogs ingest infected copepods (crustaceans that have ingested coracidia, i.e., Spirometra spp. embryos) and serve as a secondary intermediate host. Complete surgical excision is recommended for definitive diagnosis and treatment. Granulomatous inflammation is the most common histologic finding. Although dissemination can occur, most cases are localized. Serum enzyme-linked immunosorbent assay (ELISA) has been suggested as a potential surveillance tool. Medical therapy with antiparasitic agents, such as praziquantel, is not typically recommended but may be effective at high doses. Preventing recurrence thus depends on adequate surgical removal of the parasite. We report a case of a breast mass caused by sparganosis infection in a Chinese female whose likely exposure was due to frog consumption. The diagnosis was confirmed on surgical excision and no systemic antiparasitic therapy was required.

Eosinophilic pleural effusion due to Spirometra mansoni spargana: a case report and review of the literature.

A 36-year-old female presented with an eosinophilic pleural effusion. The eosinophilic pleural effusion was considered to have been caused by a parasitic infection. Spirometra mansoni spargana was confirmed by semi-rigid thoracoscopy. About 2 months after treatment with praziquantel for 3 days, the pleural effusion had disappeared on the chest roentgenogram.

A waterborn zoonotic helminthiase in an Italian diver: a case report of a cutaneous Sparganum infection and a review of European cases.

Many waterborne helminthes are opportunistic parasites that can travel directly from animals to man and may contain forms capable of penetrating the skin. Among these, Sparganum is the pseudophyllidean tapeworm that belongs to the genus Spirometra, which is responsible for parasitic zoonosis; it is rarely detected in Europe and is caused by the plerocercoid infective larva. Thus far, only six cases of cutaneous and ocular sparganosis have been reported in Europe; two and four cases have occurred in France and Italy, respectively. Herein, we describe a new case of sparganosis in Italy that affected a male diver who presented to the Bambino Gesù Children's Hospital of Rome. The patient's skin biopsy was submitted to the Parasitology department who, in consultation with Pathology, concluded that the morphologic and microscopic findings were those of Sparganum spp. larvae. The patient recovered following a single dose of 600 mg praziquantel.