Difficulty in diagnosing a case with apparent sequel cerebral sparganosis

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.

Molecular Characterization of Spirometra erinaceieuropaei from Jungle Cat (Felis chaus) in North of Iran

PURPOSE

The aim of this study is to conduct a molecular characterization of Spirometra tapeworm from jungle cat (Felis chaus) in Guilan Province, north of Iran using DNA sequence analysis of the mitochondrial cytochrome c oxidase subunit 1 (Cox1) and 12S rDNA sequences.

METHODS

Morphological features of the adult tapeworm of Spirometra were evaluated using specific staining and light microscopy. The molecular characterization was performed using partial Cox1 and 12S rDNA regions. Genetic diversity was calculated and phylogenetic trees of the obtained sequences were constructed.

RESULTS

Morphological features were compatible with previous description of adult Spirometra erinaceieuropaei. The Cox1 sequence of the specimen showed 100% similarity with S. erinaceieuropaei sequences in GenBank from Korea, China and Iran. Also, the 12S rDNA sequence revealed 99.7% similarity with S. erinaceieuropaei isolates from China and Japan. Intra-species variation within isolates of S. erinaceieuropaei was 0-1.4% and 0-4.6% for Cox1 and 12S rDNA genes, respectively.

CONCLUSION

This is the first report of molecular characterization of S. erinaceieuropaei in jungle cat, F. chaus in Iran. Jungle cat probably plays a major role as reservoir host in maintaining of this parasite in this area with favorable climate condition. Needs for further assessment on the role of appropriate hosts, especially intermediate/paratenic hosts as well as the potential risk of human infectivity with sparganosis is emphasized.

Proteomic and Immunological Identification of Diagnostic Antigens from Spirometra erinaceieuropaei Plerocercoid

Human sparganosis is a food-borne parasitic disease caused by the plerocercoids of Spirometra species. Clinical diagnosis of sparganosis is crucial for effective treatment, thus it is important to identify sensitive and specific antigens of plerocercoids. The aim of the current study was to identify and characterize the immunogenic proteins of Spirometra erinaceieuropaei plerocercoids that were recognized by patient sera. Crude soluble extract of the plerocercoids were separated using 2-dimensional gel electrophoresis coupled with immunoblot and mass spectrometry analysis. Based on immunoblotting patterns and mass spectrometry results, 8 antigenic proteins were identified from the plerocercoid. Among the proteins, cysteine protease protein might be developed as an antigen for diagnosis of sparganosis.

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.

Genetic Identification of Spirometra erinaceieuropaei Spargana in Liaoning and Hubei Provinces, PR China

Spargana were collected from human and frogs in Liaoning and Hubei Provinces, China. PCR amplification and direct sequencing of A cox1 fragment was PCR-amplified from genomic DNA extracted from 7 specimens (5 from humans and 2 from frogs). The cox1 fragment (390 bp) showed 97–100% similarity to the reference sequence of S. erinaceieuropaei and 88–89% to the reference sequence of S. decipiens. There were 1–12 bases different between these worms, but no obvious genetic variation (0–3.3%) to the references. There was little difference of cox1 gene between sparganum samples of humans and frogs (1–3%). This study is the first report on S. erinaceieuropaei spargana from humans in Liaoning and Hubei Provinces.

Characterization of Spirometra erinaceieuropaei Plerocercoid Cysteine Protease and Potential Application for Serodiagnosis of Sparganosis

Background

Sparganosis is a neglected but important food-borne parasitic zoonosis. Clinical diagnosis of sparganosis is difficult because there are no specific manifestations. ELISA using plerocercoid crude or excretory–secretory (ES) antigens has high sensitivity but has cross-reactions with other helminthiases. The aim of this study was to characterize Spirometra erinaceieuropaei cysteine protease (SeCP) and to evaluate its potential application for serodiagnosis of sparganosis.

Methodology/Principal Findings

The full length SeCP gene was cloned, and recombinant SeCP (rSeCP) was expressed and purified. Western blotting showed that rSeCP was recognized by the serum of sparganum-infected mice, and anti-rSeCP serum recognized the native SeCP protein of plerocercoid crude or ES antigens. Expression of SeCP was observed at plerocercoid stages but not at the adult and egg stages. Immunolocalization identified SeCP in plerocercoid tegument and parenchymal tissue. The rSeCP had CP activity, and the optimum pH and temperature were 5.5 and 37°C, respectively. Enzymatic activity was significantly inhibited by E-64. rSeCP functions to degrade different proteins and the function was inhibited by anti-rSeCP serum and E-64. Immunization of mice with rSeCP induced Th2-predominant immune responses and anti-rSeCP antibodies had the potential capabilities to kill plerocercoids in an ADCC assay. The sensitivity of rSeCP-ELISA and ES antigen ELISA was 100% when performed on sera of patients with sparganosis. The specificity of rSeCP-ELISA and ES antigen ELISA was 98.22% (166/169) and 87.57% (148/169), respectively (P<0.05).

Conclusions

The rSeCP had the CP enzymatic activity and SeCP seems to be important for the survival of plerocercoids in host. The rSeCP is a potential diagnostic antigen for sparganosis.

Sparganosis is a neglected tropical disease; its diagnosis is difficult and it is often misdiagnosed. ELISA using the crude or ES antigens of plerocercoids cross reacts with other helminthiases. Cysteine protease is a type of hydrolase and plays important roles in the development and survival of parasites; it has been used for diagnostic markers and vaccine targets for some parasitic diseases. In this study, a 36 kDa Spirometra erinaceieuropaei cysteine protease (SeCP) was expressed and purified. The results showed that SeCP was a plerocercoid stage-specific protein located in the teguments and parenchymal tissue. The rSeCP had cysteine protease activity and functioned to degrade host proteins. Vaccination of mice with rSeCP induced high levels of IgG1 and anti-rSeCP antibodies with the ability to kill plerocercoids in an ADCC assay. The rSeCP had a high sensitivity and specificity for detecting anti-plerocercoid antibodies, and could be used as a potential antigen for serodiagnosis of sparganosis.

Pulmonary sparganosis mansoni: a case report from a non-endemic region

Sparganosis mansoni is a parasitic disease caused by the larva of Spirometra mansoni. It occurs worldwide, but only a few patients show pulmonary involvement. Here, we present a case of pulmonary sparganosis mansoni in a non-endemic region. A 32-year-old Chinese woman presented with intermittent bloody phlegm, peripheral blood eosinophilia, and migratory patch shadows in both lungs. She had been misdiagnosed with eosinophilic pneumonia. She had a history of eating raw frogs, and the sparganum mansoni antibody was positive in both her blood and bronchoalveolar lavage fluid. Several sparganum mansoni were found in a frog sample that the patient provided. Consequently, she was diagnosed with pulmonary sparganosis mansoni. After two oral courses of praziquantel were administered, her symptoms and radiological lesions improved significantly. To our knowledge, this is the first case of pulmonary sparganosis mansoni occuring in Shanghai. Oral praziquantel is effective for the treatment of sparganosis mansoni, although its course of therapy may need to be repeated.

Analysis of structures, functions, and epitopes of cysteine protease from Spirometra erinaceieuropaei Spargana

Spirometra erinaceieuropaei cysteine protease (SeCP) in sparganum ES proteins recognized by early infection sera was identified by MALDI-TOF/TOF-MS. The aim of this study was to predict the structures and functions of SeCP protein by using the full length cDNA sequence of SeCP gene with online sites and software programs. The SeCP gene sequence was of 1 053 bp length with a 1011 bp biggest ORF encoding 336-amino acid protein with a complete cathepsin propeptide inhibitor domain and a peptidase C1A conserved domain. The predicted molecular weight and isoelectric point of SeCP were 37.87 kDa and 6.47, respectively. The SeCP has a signal peptide site and no transmembrane domain, located outside the membrane. The secondary structure of SeCP contained 8 α -helixes, 7 β -strands, and 20 coils. The SeCP had 15 potential antigenic epitopes and 19 HLA-I restricted epitopes. Based on the phylogenetic analysis of SeCP, S. erinaceieuropaei has the closest evolutionary status with S. mansonoides. SeCP was a kind of proteolytic enzyme with a variety of biological functions and its antigenic epitopes could provide important insights on the diagnostic antigens and target molecular of antisparganum drugs.

Migration: a notable feature of cerebral sparganosis on follow-up MR imaging

BACKGROUND AND PURPOSE

Cerebral sparganosis is a rare parasitic infection caused by sparganum, which can migrate in the brain. The purpose of this study was to demonstrate the migration of cerebral sparganosis and describe its patterns on MR imaging.

MATERIALS AND METHODS

MR images of 14 patients with cerebral sparganosis treated from 2005 to 2011 were retrospectively reviewed. Diagnosis was made on the basis of a constellation of clinical history, laboratory tests, imaging findings, and histopathology. At least 3 MR imaging studies were performed for each patient during the follow-up period ranging from 12 to 38 months. Time interval, sites, enhanced pattern, and presumed routes of migration were evaluated.

RESULTS

Both the initial lesions and migrated ones exhibited the "tunnel" sign and multiloculated rim enhancement. Migration was detected between 4 and 18 months after the baseline MR imaging in 14 lesions (in 14 patients), while 3 of 14 lesions showed a second migration between 22 and 38 months. Nearly all migrations were limited to the same hemisphere except for 2 contralateral migrations through the thalamus. Most of the migrations were in close proximity (within the same lobe, to the adjacent lobe, from the basal ganglia to the cortex, from the cerebellum to the pons and interthalamus) except 1 from the basal ganglia to the cerebellum. A signal change along the presumed route of migration was seen in 3 patients.

CONCLUSIONS

Migration is a notable feature of cerebral sparganosis. Demonstration of migration on MR imaging could be a key diagnostic clue and beneficial for the treatment policy.

Diagnosis and stereotactic aspiration treatment of cerebral sparganosis: summary of 11 cases

Object

Cerebral sparganosis is a rare but underestimated parasitic disease caused by infestation by sparganum. It is difficult to make a confirmed preoperational diagnosis of this disease given the absence of characteristic clinical manifestations. A detailed protocol for the diagnosis and treatment of cerebral sparganosis is still lacking in the literature. In this article the authors set out comprehensive procedures for the diagnosis and treatment of cerebral sparganosis, describing the use of a stereotactic aspiration technique complemented by microsurgery based on experience gained from multiple cases.

Methods

The disease history, clinical manifestations, imaging features, and therapeutic procedures for 11 patients with cerebral sparganosis were retrospectively analyzed. Stereotactic aspiration procedures were performed in all 11 patients and were complemented by microsurgeries in 3 patients. The learning and experience gained from these treatments were summarized, and a comprehensive protocol for the diagnosis and treatment of cerebral sparganosis was reviewed.

Results

Larvae of Spirometra mansoni were taken from all 11 patients: completely removed in 10 cases and partially removed in 1 case (discovered later). After surgery, clinical symptoms in all 11 patients were significantly improved. All epileptic symptoms were successfully cured, although in 1 case occasional seizures still occurred because of the incomplete removal of the larva. Muscle strength in the 4 patients who had hemiparesis prior to surgery recovered to normal. Symptoms in the 1 patient who had presented with partial body sensory disturbance resolved after surgery. There were no complications or deaths.

Conclusions

The authors concluded that an effective preoperative diagnosis of cerebral sparganosis can be made by detailed inquiry into the possible infection history and disease symptoms as well as careful scrutiny of characteristic radiological features and immunological testing results. In stereotactic operations performed to remove the larva, priority should be given to image-guided stereotactic aspiration given that it causes the smallest wounds. In cases in which stereotactic aspiration fails, stereotactic microsurgery should be performed to remove the larva. The surgeon must carefully avoid breaking the larva and leaving behind any larva residue during surgery.

Serodiagnosis of experimental sparganum infections of mice and human sparganosis by ELISA using ES antigens of Spirometra mansoni spargana

We conducted a study of serodiagnosis of experimental sparganum infections of mice and human sparganosis by enzyme-linked immunosorbent assay (ELISA) using excretory-secretory (ES) antigens of Spirometra mansoni spargana and compared the sensitivity and specificity of crude and ES antigens for detecting the specific anti-sparganum IgG antibodies. By crude antigen ELISA and ES antigen ELISA, anti-sparganum IgG was detected in all of 30 serum samples of the infected mice; no cross-reactions were observed in serum samples of the mice infected with Trichinella spiralis, Schistosoma japanicum, Toxoplasma gondii, and normal mice. Anti-sparganum IgG was detected by ES antigen ELISA in sera of mice infected with one, two, four, six, and eight spargana at 3 weeks post-infection (wpi), with a detection rate of 100%, and lasted to 18 wpi when the experiment was ended. The difference in anti-sparganum antibody levels among five groups of the infected mice was statistically significant (F=245.296, p<0.05); the antibody levels were correlated with infecting doses of spargana (r=0.323, p<0.05). The sensitivity of both ELISA in detecting the serum samples of patients with sparganosis was 100% (20/20), but 96.72% (59/61) of specificity of ES antigen ELISA in detecting serum samples of patients with cysticercosis, echinococcosis, paragonimiosis, clonorchiosis, and schistosomiasis, and healthy persons was significantly greater than 72.13% (44/61) of crude antigen ELISA (χ (2) = 14.027, p<0.05). Our finding indicates that ELISA using ES antigens of S. mansoni spargana may be applied to the specific early serodiagnosis of sparganosis.

Helminthic parasites and seizures

A large number of helminthic parasites are known to involve the central nervous system (CNS) and produce neurologic symptoms including seizures and epilepsy. Taenia solium (the pork tapeworm) is perhaps most widely prevalent and well known for its association with seizures and epilepsy. Many of the other helminthic disorders have fairly restricted geographic predilections and their occurrence in much of the remaining world is limited to rare cases among travelers and immigrants. Nonetheless, knowledge about the helminthic disorders, the life cycle of their causative agents, and their clinical manifestations and diagnostic features are important in order to recognize them.