Neurocysticercosis

Neurocysticercosis-Induced Monoparesis: A Case Report of a Rare Neurological Manifestation

Neurocysticercosis (NCC), a disease caused by the larval form of the pork tapeworm Taenia solium, is a common cause of acquired epilepsy globally, especially in areas with poor sanitation. While seizures and headaches are common manifestations, cases of NCC leading to monoparesis are exceedingly rare. Here, we describe a distinctive case of a 42-year-old male who developed sudden weakness and spasms in his left hand without prior injury or other systemic symptoms. Magnetic resonance imaging (MRI) of the brain revealed a single cystic lesion in the right frontoparietal lobe indicative of NCC, which was the cause of his pure motor monoparesis (PMM), without any sensory loss. Treatment with dexamethasone and albendazole substantially improved his motor abilities, highlighting the necessity of considering NCC in differential diagnoses for monoparesis, particularly in endemic areas. This case adds a unique perspective to the clinical spectrum of NCC, highlighting the critical role of prompt and accurate diagnosis followed by appropriate treatment in achieving favorable outcomes.

Racemose neurocysticercosis: a case series

Neurocysticercosis (NCC) is a common parasitic condition of the central nervous system in certain parts of the world. The racemose variety of NCC is distinct from the commonly seen parenchymal form. It frequently infiltrates the basal cisterns and Sylvian fissures. Imaging plays a vital role in the diagnosis; however, as their signal intensity is similar to cerebrospinal fluid and due to the absence of enhancement in most cases, imaging diagnosis is often difficult on the conventional MRI sequences. Here, we present five cases of racemose NCC to emphasize the importance of a heavily T2-weighted sequence (Fast Imaging Employing Steady-state Acquisition) sequence in the diagnosing this entity.

Clinical Characteristics of Neurocysticercosis in a Peruvian Population-Based Epilepsy Cohort: A Descriptive Cross-Sectional Study of Baseline Clinical Intake

(1) Background: This study presents the baseline characteristics of a community-level population of people with epilepsy (n = 1975) living in an area endemic for Taenia solium, the pathogen responsible for neurocysticercosis (NCC). (2) Methods: Participants were sequentially enrolled in a clinical cohort from 2007 to 2020 in Tumbes, Peru. All participants provided demographic and clinical history and received clinical evaluations. Diagnostics, including neuroimaging, cysticercosis serologies, and EEG, were obtained where possible. The data presented are from the cross-sectional baseline assessment of cohort participants. (3) Results: Approximately 38% of participants met the criteria for NCC. Those with NCC were more likely to have adult-onset epilepsy, as well as a longer duration of epilepsy, as compared to their counterparts without NCC. Overall, the data indicate a large treatment gap, with only approximately a quarter of the baseline population with prescriptions for anti-seizure medications. (4) Conclusions: These data reveal a high proportion of NCC among people living with epilepsy in these communities, with limited health care resources. At baseline, 74% of the population were not receiving anti-seizure treatments. Further analyses of these data will clarify the natural history of the disease for this population.

Microsurgical and endoscopic-assisted supraorbital keyhole approach for intra-suprasellar cysticercosis

Background

Treatment for intra/suprasellar cysticercosis can be challenging and may result in visual disturbances if not managed properly. Despite its limited knowledge, an effective surgical option exists to treat this condition. This article presents three cases of sellar cysticercosis, comprising one female and two male patients, managed with microsurgical supraorbital keyhole approach (mSKA) and endoscopic-assisted supraorbital keyhole approach (eaSKA).

Case Description

The first patient is a 35-year-old man with no prior medical history who suffered from memory deficits and visual disturbances due to a sellar cyst pushing the orbitofrontal gyrus treated with mSKA. The second case involved a 52-year-old man who experienced visual deficits caused by a rostral sellar cyst with posterior displacement of the pituitary gland treated with eaSKA. The third case was a 46-year-old woman who experienced decreased visual acuity and memory loss due to multifocal neurocysticercosis (NCC) with sellarsuprasellar cyst extension treated with mSKA. All case diagnoses were confirmed by neuropathology department.

Conclusion

The authors confidently suggest that the SKA is an effective surgical option and could be considered for removing sellar cystic lesions with suprasellar extension. With endoscopic assistance, it improves adequate neurovascular structure visualization.

Recurrent syncopal episodes in a pregnant patient with neurocysticercosis

Neurocysticercosis (NCC) is the most common parasitic infection of the nervous system and acquired epilepsy in low-resource settings due to the pork tapeworm, Taenia solium. Humans contract the intestinal infection of the adult tapeworm (taeniasis) through the fecal-oral route after consuming undercooked food, particularly pork or water, contaminated with tapeworm eggs. When the larvae invades the central nervous system (CNS), the infection causes NCC, which often manifests as late-onset seizures, chronic headaches, and intracranial hypertension. We describe a 31-year-old Hispanic multigravida woman from Guatemala, at 33 weeks of gestation, who presented with multiple syncopal and hypotensive episodes prompting a Computed tomography (CT) image of the head revealing multiple small cerebral calcifications indicating NCC. In this article, we highlight the significance of early symptom recognition and diagnostic workup for NCC in areas with diverse immigrant populations. We also discuss the epidemiology, clinical manifestations, and current treatment modalities available for NCC.

Neurocysticercosis-related Seizures: Imaging Biomarkers

Neurocysticercosis (NCC)-a parasitic CNS infection endemic to developing nations-has been called the leading global cause of acquired epilepsy yet remains understudied. It is currently unknown why a large proportion of patients develop recurrent seizures, often following the presentation of acute seizures. Furthermore, the presentation of NCC is heterogenous and the features that predispose to the development of an epileptogenic state remain uncertain. Perilesional factors (such as oedema and gliosis) have been implicated in NCC-related ictogenesis, but the effects of cystic factors, including lesion load and location, seem not to play a role in the development of habitual epilepsy. In addition, the cytotoxic consequences of the cyst's degenerative stages are varied and the majority of research, relying on retrospective data, lacks the necessary specificity to distinguish between acute symptomatic and unprovoked seizures. Previous research has established that epileptogenesis can be the consequence of abnormal network connectivity, and some imaging studies have suggested that a causative link may exist between NCC and aberrant network organisation. In wider epilepsy research, network approaches have been widely adopted; studies benefiting predominantly from the rich, multimodal data provided by advanced MRI methods are at the forefront of the field. Quantitative MRI approaches have the potential to elucidate the lesser-understood epileptogenic mechanisms of NCC. This review will summarise the current understanding of the relationship between NCC and epilepsy, with a focus on MRI methodologies. In addition, network neuroscience approaches with putative value will be highlighted, drawing from current imaging trends in epilepsy research.

Knowledge and practices about taeniasis/cysticercosis complex within the framework of the national plan for its elimination in Colombia, 2019

The taeniasis/cysticercosis complex (TCC) belongs to the group of neglected infectious diseases with a multifactorial transmission that includes hosts such as humans and pigs of the parasitic tapeworm (Taenia solium) and environmental factors. This study represents the first phase of the National and Cross-sectoral Plan for TCC Elimination.

OBJECTIVES

To obtain data about knowledge and practices in relation to the TCC from knowledge, attitudes, and practices (KAP) surveys applied in two pilot localities for building a baseline of the potential risk factors related to identification, prevention, and control of TCC in Colombia.

METHODS

A descriptive cross-sectional survey from October to November in 2019 was carried out using a structured questionnaire and random sampling by single-stage conglomerates in the municipalities of Mahates, Bolívar (n=152) (Atlantic Region) and Mercaderes, Cauca (n=152) (Andean Region).

RESULTS

Respondents in Mahates showed moderate knowledge about TCC compared to those in Mercaderes, however, risky practices were identified in both places (consumption of pork with cysts and defecation in places other than the bathroom or latrine). Deficiency in infrastructure and failure in basic services were observed as potential risk factors for TCC transmission in both municipalities.

CONCLUSION

Based on the framework of the National and Cross-sectoral Plan for TCC Elimination, adequate knowledge on identification, prevention, and control of the disease must be reinforced; cultural and ecological differences should be considered when designing communication and knowledge transmission tools. We consider that major investment should be made in improving basic services and creating sustainable modernized pig farming in Mahates and Mercaderes.

Neurocysticercosis in non-endemic regions: The experience of Qatar

Objective

To describe the occurrence and features of Neurocystircercosis (NCC) in Qatar.

Background

Qatar has a mixed population of natives and expats. NCC is not endemic to the region, but clinical practice suggests its occurrence in large numbers.

Design/ methods

A database was created to summarize information retrospectively collected on patients with NCC seen through the national health system (HMC) between 2013 and 2018. We identified demographic and disease related variables (clinical manifestations, investigative findings, treatment and outcome) for all patients.

Results

Out of 420 identified NCC patients, 393 (93.6%) were men, and 98.3% were immigrants from NCC endemic countries such as Nepal (63.8%) and India (29.5%). Eighty percent of patients presented with seizures, with the majority (69%) experiencing generalized tonic-clonic seizures. Five percent presented with status epilepticus. Headaches, the second most common complaint, were reported in 18% of subjects. On imaging, 50% had a single lesion while 63% included pathology at the calcified stage. The lesions were parenchymal in 99.5% of cases, predominantly in the frontal lobe (59%). Thirteen percent were diagnosed incidentally on imaging, mainly in the form of isolated calcified non enhancing lesions. Albendazole was received by 55% of patients, and phenytoin was the most prescribed anti-seizure drug (57%). When long term follow up was available, 70% of the patients presenting with seizures were completely seizure free.

Conclusion

NCC is prevalent in Qatar, mainly within the large Southeast Asian immigrant population. NCC is currently a significant contributor to the epilepsy burden in Qatar, often with a good outcome regarding seizure control. NCC with intraparenchymal single lesion shares a large proportion of our cohort.

Endoscope-assisted far lateral craniotomy for resection of posterior fossa neurocysticercosis: illustrative case

BACKGROUND

Neurocysticercosis is a parasitic infection that commonly affects the ventricles, subarachnoid spaces, and spinal cord of the central nervous system. The authors report an unusual manifestation of purely posterior fossa neurocysticercosis treated with endoscope-assisted open craniotomy for resection.

OBSERVATIONS

A 67-year-old male presented with 2 months of progressive dizziness, gait ataxia, headaches, decreased hearing, and memory impairment. Imaging revealed an extra-axial cystic lesion occupying the foramen magnum and left cerebellopontine angle with significant mass effect and evidence of early hydrocephalus. Gross-total resection was accomplished via a left far lateral craniotomy with open endoscopic assistance, and pathological findings were consistent with neurocysticercosis. Postoperatively, he was noted to have a sixth nerve palsy, and adjuvant therapy included albendazole. By 9 months postoperatively, he exhibited complete resolution of an immediate postoperative sixth nerve palsy in addition to all preoperative symptoms. His hydrocephalus resolved and did not require permanent cerebrospinal fluid (CSF) diversion.

LESSONS

When combined with traditional skull base approaches, open endoscopic techniques allow for enhanced visualization and resection of complex lesions otherwise inaccessible under the microscope alone. Recognition and obliteration of central nervous system neurocysticercosis can facilitate excellent neurological recovery without the need for CSF diversion.

Neurocysticercosis presenting as psychosis: A case report and a brief literature review

Patients with neurocysticercosis, a common infection of the central nervous system caused by Taenia solium, have been reported to develop neuropsychiatric complications. We report a unique case of recurrent psychosis caused by neurocysticercosis in a 37-year-old El Salvador immigrant woman and discuss the underlying pathophysiological mechanisms of the complications. We reviewed published case reports of neurocysticercosis that presented with psychotic features and compared their diagnostic evaluation, the underlying pathophysiology of complications and treatment regimen with our case. This review concludes that neurocysticercosis should be considered in the differential diagnosis of patients presenting with psychosis with a history of residence in an endemic area.

Parasitic Infections in Internationally Adopted Children: A Twelve-Year Retrospective Study

Parasitic infections (PIs) are among the most frequent infectious diseases globally. Previous studies reported discrepant results regarding the prevalence of PIs in internationally adopted children (IAC). Data from IAC referred to our paediatric university hospital in 2009–2021 were collected to evaluate the frequency of PIs by the use of stool microscopic examination, antigen assays for Giardia lamblia and Cryptosporidium parvum, and serological tests for Toxocara canis, Strongyloides stercoralis, Schistosoma mansoni, Echinococcus spp., Taenia solium, and Trypanosoma cruzi. Uni- and multivariate logistic regression analyses were performed to evaluate risk factors for PIs and eosinophilia. The proportion of IAC with at least one positive test was 26.83% (640/2385); 2.13% (n = 51) had positive tests for 2 or 3 parasites. A positive assay for helminthic infection was retrieved in 11.07% of children (n = 264), and 17.86% (n = 426) presented with eosinophilia. The most common positive tests were anti-Toxocara canis antibodies (n = 312; 13.8%), followed by positive stool antigen for Giardia lamblia (n = 290; 12.16%), and positive microscopic stool examination for Blastocystis hominis (n = 76; 3.19%). A statistically significant association was found between PIs and region of origin (children from Latin America and Africa were more likely to present PIs than children from Eastern Europe), age 5–14 years, and eosinophilia. No significant association was observed between PIs and gender, vitamin D deficiency, or anemia. In conclusion, PIs are relevant in IAC and an accurate protocol is needed to evaluate IAC once they arrive in their adoptive country.

Spinal cysticercosis: a rare cause of myelopathy

Background

Neurocysticercosis is a neuroinfectious disease caused by the larval stage of the tapeworm Taenia solium. Isolated spinal cysticercosis is rare, with limited cases having been reported in the literature. This entity poses great diagnostic and therapeutic challenges.

Methods

This retrospective study included seven patients pathologically diagnosed with spinal cysticercosis. The clinical manifestations, radiological features on magnetic resonance imaging (MRI), treatment, and outcomes were analyzed.

Results

This case series consisted of four male and three female patients, with an average age of 34.9 ± 10.9 years. Clinically, six patients manifested with localization-related myelopathy. There were four solid lesions, one cystic-solid lesion, and three cystic lesions. The solid and cystic-solid lesions showed characteristic MRI features: 1) within the lesion, there was a mural nodule with isointensity on T1WI and iso- to hyperintensity on T2WI; 2) the signals at the periphery of the mural nodule were variable, ranging from hypointense to hyperintense on T2WI; and 3) ring-like or cyst wall enhancement could be present, and dot-like enhancement could be noted in the mural nodule. Complete resection of the responsible lesion was achieved in all patients, and oral albendazole was administered in a patient with one more suspected homologous lesion. After a mean follow-up period of 56.7 ± 35.1 months, the patient’s symptoms mostly regressed.

Conclusion

Spinal cysticercosis is an extremely rare cause of myelopathy. Characteristic MRI features can facilitate preoperative diagnosis. Clinicians should be aware of this entity, and it should be included in the differential diagnosis of myelopathy.

A Case of Sellar/Suprasellar Neurocysticercosis Mimicking a Craniopharyngioma

Neurocysticercosis (NCC) commonly presents with seizures in developing countries such as Nepal. It may also present with raised intracranial pressure due to obstructive hydrocephalus when cyst is located in the fourth ventricle or foramen of Monro. There are four main stages of NCC (1) Vesicular, (2) Colloidal vesicular, (3) Granular nodular, and (4) Nodular calcified. The colloidal vesicular stages can cause arachnoiditis and thus can cause hydrocephalus whereas obstructive hydrocephalus is usually caused by racemose type of NCC. This case was a suprasellar cyst mimicking craniopharyngioma, supported with clinical history of poor visual acuity, endocrine abnormality, suggested radiological findings by computed tomography scan, and magnetic resonance imaging. Suprasellar NCC was confirmed only by intraoperative findings and histopathology report.

Subarachnoid racemose neurocysticercosis with cerebellar involvement: an old friend in an infrequent location?

Taenia solium is the most common parasitic infection of the central nervous system and it can cause parenchymal or extra-parenchymal lesions. Subarachnoid cysticercosis is a type of extra-parenchymal infection in which the prevalence is not known and racemose NC with cerebellar involvement has been rarely reported. The diagnosis is challenging because of its similarity to other infectious diseases or to subarachnoid involvement of systemic malignancies. Treatment usually requires cysticide drugs, however, there are no randomized studies concerning the anti-parasitic treatment in subarachnoid NC. We present a case of racemose NC in the cerebellar hemisphere to draw attention to this pathology, endemic in many parts of the world; and highlight all the current gaps in our understanding of this entity.

Neurocysticercosis: Current Perspectives on Diagnosis and Management

Porcine cysticercosis, human taeniasis, and (neuro)cysticercosis are endemic in many low- and middle-income countries (LMIC) where they present a significant health burden to affected communities. Neurocysticercosis (NCC) is one of the leading causes of human epilepsy in many hyperendemic regions in Latin America, Asia, and sub-Saharan Africa. The World Health Organization (WHO) reports an estimated 2.5-8.3 million cases of NCC annually with a disability-adjusted life year (DALY) burden of 2.8 million, but as for all neglected tropical diseases (NTDs), these values are likely to be underestimated. Diagnosis of NCC is complex and most accurately diagnosed using clinical neuroimaging that is unavailable in most hyperendemic regions in LMIC. On January 28, 2021, WHO will launch its road map for the NTDs' "Ending the neglect to attain the Sustainable Development Goals: a road map for neglected tropical diseases 2021-2030." Taeniasis/cysticercosis is targeted for control success considered as steady increase in the number of countries with intensified control in hyperendemic areas [increasing from 2 (3%) in 2020 to 4 (6%) in 2023, to 9 (14%) by 2025, and to 17 (27%) by 2030]. Cross-cutting targets that include 100% access to at least basic water supply, sanitation, and hygiene in areas endemic for NTDs and 75% integrated treatment coverage for preventative chemotherapy will additionally impact on the taeniasis/cysticercosis/NCC complex. With no vaccine available for humans, prevention of infection depends on communication to the public of the life cycle of a complex zoonosis to promote behavior change, underpinned by practical control measures including treatment of human taeniasis and (neuro)cysticercosis with albendazole and praziquantel [widely used as part of the mass drug administration (MDA) deworming programs], surgery where appropriate, and effective vaccination and deworming for pigs supported by meat inspection. Here, we review recent advances in tools and implementation for Taenia solium taeniasis/(neuro)cysticercosis (TSTC) control and milestones on the onward path to elimination.

Imaging Mimics of Brain Tumors

Nonneoplastic entities may closely resemble the imaging findings of primary or metastatic intracranial neoplasia, posing diagnostic challenges for the referring provider and radiologist. Prospective identification of brain tumor mimics is an opportunity for the radiologist to add value to patient care by decreasing time to diagnosis and avoiding unnecessary surgical procedures and medical therapies, but requires familiarity with mimic entities and a high degree of suspicion on the part of the interpreting radiologist. This article provides a framework for the radiologist to identify "brain tumor mimics," highlighting imaging and laboratory pearls and pitfalls, and illustrating unique and frequently encountered lesions.

Infectious Myelopathies

PURPOSE OF REVIEW

This article reviews infectious etiologies of spinal cord dysfunction, emphasizing the importance of recognizing common clinicoradiographic syndromes and interpreting them in the context of exposure risk and individual host susceptibilities.

RECENT FINDINGS

This article discusses the shifting spectrum of neurologic infectious diseases, the growing population of patients who are immunocompromised, and the emergence of effective antiretroviral therapies. In addition, it discusses new molecular and serologic tests that have the potential to enhance our ability to rapidly and accurately diagnose infectious diseases of the spine.

SUMMARY

When evaluating patients with suspected infectious myelopathies, it is imperative to narrow the range of pathogens under consideration. The geography, seasonality, and clinicoradiographic presentation and immunocompetence status of the patient define the range of potential pathogens and should guide testing and initial management.

Environmental neurology in the tropics

We address the impact of the tropical environment on the human nervous system using the multifaceted approach characteristic of environmental neurology. First, environmental factors are examined according to their nature (physical, chemical and biological) and in relation to human activity and behavior. Some factors are specific to the tropics (climate and infections), while others are non-specific (chemicals, human communities and their way of life). Second, we examine the major role of human adaptation to the success of Homo sapiens, with emphasis on the linkage between thermoregulation and sleep-wake regulation. Third, we examine the performance of environmental neurology as a clinical discipline in tropical climates, with focus on the diagnostic and therapeutic challenges posed by human African trypanosomiasis. Finally, the prevention, early detection and monitoring of environmental neurological diseases is examined, as well as links with political and economic factors. In conclusion, practitioners of environmental neurology seek a global, multidisciplinary and holistic approach to understanding, preventing and treating neurological disorders within their purview. Environmental neurology integrates an expanded One Health concept by linking health and wellness to the interaction of plants, animals, humans and the ecosystem. Recent epidemics and the current COVID-19 pandemic exemplify the need for worldwide action to protect human health and biodiversity.

Imported cysticercosis in Spain: A retrospective case series from the +REDIVI Collaborative Network

BACKGROUND

Neurocysticercosis (NCC) is the most common parasitic neurological disease worldwide and a major cause of epilepsy. Spain is the country reporting the highest number of NCC imported cases in Europe.

METHODOLOGY

Retrospective case series of NCC patients registered in the +REDIVI Network from October 1, 2009 to July 2018. A specific questionnaire, including clinical and diagnostic characteristics, was created and sent to the collaborator centers.

RESULTS

46 cases were included in the analysis. 55% were male, mean age of 40 years. 95.6% were migrants. The median duration since migration from an endemic area was 10 years. Predominant nationalities were Ecuadorians (50%) and Bolivians (30.4%). Frequent locations were parenchymal (87%), subarachnoid (26.1%) and intraventricular cysts (10.9%). Serological analysis was performed in 91.3%, being 54.8% positive. Most prevalent clinical manifestations were persistent headache (60.9%), epilepsy (43.5%) and visual changes (13%). Patients were mainly treated with albendazole (76.1%), corticosteroids (67.4%), and anticonvulsionants (52.2%). 82.5% had a favorable clinical outcome.

CONCLUSIONS

Most NCC cases were long-standing migrants. Few clinical differences were observed depending on the cysticerci location. The treatment was often not according to current recommendations, and no uniform criteria were followed when it came to the therapeutic regimen. NCC case management in Spain (including clinician awareness and laboratory capacity improvements) needs to be strengthened.

Systematic Review and Meta-Analysis of Management Strategies and Outcomes in Adult Spinal Neurocysticercosis

OBJECTIVE

Spinal involvement in neurocysticercosis is rare and can lead to debilitating injury if not diagnosed and treated early. We aim to provide the reader with a thorough analysis of the best available evidence regarding patient characteristics, optimal treatment modality, and outcomes in cases of spinal neurocysticercosis.

METHODS

A systematic review of the literature using PubMed, Google Scholar, and Web of Science electronic databases was made according to the PRISMA guidelines. An illustrative case of intramedullary-cervical spinal disease is also presented for illustrative purposes.

RESULTS

A total of 46 reports of 103 patients fitting the screening criteria were identified. Isolated spinal involvement was seen in 46.15% of patients. Most infections (76.92%) had an intradural extramedullary localization, with 43.27% of cases involving >1 spinal cord level. The most common presenting symptoms were motor deficits (77.88%), pain syndromes (64.42%), and sensory deficits (53.85%). Combined surgical resection and pharmacologic therapy was the most frequently used treatment modality (49.04%) and had the highest proportion of patients reporting symptomatic improvement at follow-up (78.43%). Combination therapy had a significantly higher rate of neurologic recovery compared with surgery alone (P = 0.004) or medical treatment (P = 0.035).

CONCLUSIONS

Spinal involvement in neurocysticercosis should be considered in patients from or who traveled to endemic areas presenting with ring-enhancing lesions. Combined treatment with surgery followed by cysticidal and steroid medication seems to be superior to surgery or medical treatment in isolation and seems to provide the highest chances of recovery.

A radiological and clinical description of metastatic angiosarcoma simulating a hydatid cyst

Los angiosarcomas son sarcomas malignos que se originan en las células endoteliales vasculares. Su diagnóstico diferencial es muy amplio debido a su parecido con otras enfermedades, como las parasitarias, y usualmente es un diagnóstico por exclusión. La neurocisticercosis y la hidatidosis cerebral son parasitosis intestinales que pueden comprometer el sistema nervioso central y tienen mayor incidencia en los países suramericanos.

El diagnóstico se establece a partir del perfil epidemiológico, el estudio parasitológico, la apariencia radiológica de las lesiones y el estudio de histopatología del espécimen.

Se presenta el caso de una adolescente con factores de riesgo para parasitosis y neuroimágenes sugestivas de hidatidosis cerebral, cuyo diagnóstico definitivo fue angiosarcoma cardiaco metastásico.

Structural Equation Modeling (SEM) of Cysticercosis in School-Aged Children in Tibetan Rural Farming Areas of Western China: Implications for Intervention Planning

Neurocysticercosis (NCC) significantly contributes to morbidity in developing countries. We recently published a study of prevalence and risk factors in school-aged children in three mountainous areas in Sichuan province of western China. Using structural equation modeling (SEM) on data from that study to guide intervention planning, here we examine risk factors grouped into three broad interventional categories: sociodemographics, human behavior, and sources of pork and pig husbandry. Because neuroimaging is not easily available, using SEM allows for the use of multiple observed variables (serological tests and symptoms) to represent probable NCC cases. Data collected from 2608 students was included in this analysis. Within this group, seroprevalence of cysticercosis IgG antibodies was 5.4%. SEM results showed that sociodemographic factors (β = 0.33, p < 0.05), sources of pork and pig husbandry (β = 0.26, p < 0.001), and behavioral factors (β = 0.33, p < 0.05) were all directly related to probable NCC in school-aged children. Sociodemographic factors affected probable NCC indirectly via sources of pork and pig husbandry factors (β = 0.07, p < 0.001) and behavioral variables (β = 0.07, p < 0.001). Both sociodemographic factors (β = 0.07, p < 0.05) and sources of pork and pig husbandry factors (β = 0.10, p < 0.01) affected probable NCC indirectly via behavioral variables. Because behavioral variables not only had a large direct effect but also served as a critical bridge to strengthen the effect of sociodemographics and sources of pork and pig husbandry on probable NCC, our findings suggest that interventions targeting behavioral factors may be the most effective in reducing disease.

Prevalence and risk factors for Taenia solium cysticercosis in school-aged children: A school based study in western Sichuan, People's Republic of China

Background

Taenia solium cysticercosis affects millions of impoverished people worldwide and can cause neurocysticercosis, an infection of the central nervous system which is potentially fatal. Children may represent an especially vulnerable population to neurocysticercosis, due to the risk of cognitive impairment during formative school years. While previous epidemiologic studies have suggested high prevalence in rural China, the prevalence in children as well as risk factors and impact of disease in low-resource areas remain poorly characterized.

Methodology/Principal findings

Utilizing school based sampling, we conducted a cross-sectional study, administering a questionnaire and collecting blood for T. solium cysticercosis antibodies in 2867 fifth and sixth grade students across 27 schools in west Sichuan. We used mixed-effects logistic regression models controlling for school-level clustering to study associations between risk factors and to characterize factors influencing the administration of deworming medication. Overall prevalence of cysticercosis antibodies was 6%, but prevalence was significantly higher in three schools which all had prevalences of 15% or higher. Students from households owning pigs (adjusted odds ratio [OR] 1.81, 95% CI 1.08–3.03), from households reporting feeding their pigs human feces (adjusted OR 1.49, 95% CI 1.03–2.16), and self-reporting worms in their feces (adjusted OR 1.85, 95% CI 1.18–2.91) were more likely to have cysticercosis IgG antibodies. Students attending high prevalence schools were more likely to come from households allowing pigs to freely forage for food (OR 2.26, 95% CI 1.72–2.98) and lacking a toilet (OR 1.84, 95% CI 1.38–2.46). Children who were boarding at school were less likely to have received treatment for gastrointestinal worms (adjusted OR 0.58, 95% CI 0.42–0.80).

Conclusions/Significance

Our study indicates high prevalences of cysticercosis antibodies in young school aged children in rural China. While further studies to assess potential for school-based transmission are needed, school-based disease control may be an important intervention to ensure the health of vulnerable pediatric populations in T. solium endemic areas.

The zoonotic tapeworm, Taenia solium, affects millions of impoverished people worldwide and can cause neurocysticercosis (NCC), an infection of the central nervous system which is potentially fatal. Hypothetically, children may be a vulnerable population to infection as neurological problems and cognitive impairment caused by NCC during formative school years may lead to poor academic performance, contributing to drop-out rates and, eventually, propagating cycles of poverty. We carried out a school-based study of T. solium cysticerosis in primary school-aged children in rural western Sichuan. Our results indicate high levels of T. solium exposure in young school-aged children in rural China. While further studies to assess disease transmission within schools are needed, school-based disease control may be an important intervention to ensure the health of pediatric populations at risk for infection.

Histopathologic aspects of experimental cysticercosis and in situ cytokines profile in C57BL/6 mice

ABSTRACT Neurocysticercosis (NCC) is one of the parasitic infections that most affects the central nervous system. The knowledge regarding its immunopathogenesis and pathophysiology needs broadening. Taenia crassiceps cysticerci are used as the NCC experimental model. The aim of this work was to describe the general pathological processes and the in situ cytokine profile in C57BL/6 mice inoculated intracranially with viable T. crassiceps cysticerci. The histopathology analysis showed cysticerci in the extraparenchymal and intraventricular region, mononuclear inflammatory infiltration surrounding the parasite, microgliosis and meningitis. The analysis of the in situ immune profiles showed a predominance of the Th2 response. The IL-4 and IL-10 dosages were significantly increased in the infected group. The decrease in the INF-gamma dosage reflects the immunomodulation from the cysticerci. In conclusion, a T. crassiceps NCC infection in C57BL/6 mice triggers an inflammatory response, a predominance of Th2 type in situ profile, with mononuclear inflammatory cell infiltration, meningitis and microgliosis.

Neurocysticercosis in Bhutan: a cross-sectional study in people with epilepsy

BACKGROUND

We sought to provide an assessment of the burden of neurocysticercosis among people with epilepsy (PWE) in Bhutan and evaluate the yield of various tests for Taenia solium.

METHODS

PWE were enrolled at the National Referral Hospital in Thimphu (2014-2015). Serum was tested for anti-Taenia solium IgG using ELISA (Ab-ELISA), enzyme-linked immunoelectrotransfer blot (EITB), and parasite antigen. Results were compared to brain MRI. Participants were categorized as definite neurocysticercosis (MRI and EITB positive), probable neurocysticercosis (MRI or EITB positive), or without neurocysticercosis. Logistic regression models were constructed to explore clinicodemographic associations.

RESULTS

There were 12/205 (6%, 95% CI 2%, 9%) definite and 40/205 (20%, 95% CI 14%, 25%) probable neurocysticercosis cases. 25/205 (12%) with positive EITB did not have neurocysticercosis on MRI, and 15/205 (7%) participants with positive MRI had negative EITB. Participants with neurocysticercosis-suggestive lesions on MRI had an average of 1.2 cysts (parenchymal 26/27; nodular/calcified stage 21/27). In a multivariable analysis, present age (OR 1.05, 95% CI 1.01,1.09, p=0.025) was positively associated with (combined probable or definite) neurocysticercosis while mesial temporal sclerosis on MRI (OR 0.294, 95% CI 0.144, 0.598, p=0.001) was negatively associated.

CONCLUSIONS

Neurocysticercosis was associated with 6-25% of epilepsy in a Bhutanese cohort. Combining EITB and MRI would aid the diagnosis of neurocysticercosis among PWE since no test identified all cases.

TNF-α blockade suppresses pericystic inflammation following anthelmintic treatment in porcine neurocysticercosis

Background

Neurocysticercosis (NCC) is an infection of the brain with the larval cyst of the tapeworm, Taenia solium. Cysticidal treatment induces parasite killing resulting in a post inflammatory response and seizures, which generally requires corticosteroid treatment to control inflammation. The nature of this response and how to best control it is unclear. We investigated the anti-inflammatory effects of pretreatment with etanercept (ETN), an anti-tumor necrosis factor agent, or dexamethasone (DEX), a high potency corticosteroid, on the post treatment inflammatory response in naturally infected pigs with neurocysticercosis after a single dose of the cysticidal drug praziquantel (PZQ).

Methodology/Principal findings

We followed the methods from a previously developed treatment model of NCC in naturally infected swine. The four study groups of infected pigs included 3 groups treated with PZQ on day 0: PZQ-treated alone (100 mg/kg PO; n = 9), pretreated with dexamethasone (DEX, 0.2 mg/kg IM administered on days -1, +1 and +3; n = 6), and pretreated with etanercept (ETN, 25 mg IM per animal on days -7 and 0; n = 6). The fourth group remained untreated (n = 3). As measured by quantitative RT-PCR, ETN pretreatment depressed transcription of a wide range of proinflammatory, regulatory and matrix protease encoding genes at 120 hr post PZQ treatment in capsules of cysts that demonstrated extravasated Evans Blue (EB) (a measure of blood brain barrier dysfunction) compared to animals not receiving ETN. Transcription was significantly depressed for the proinflammatory genes tumor necrosis factor (TNF)-α, and interferon (IFN)-γ; the inflammation regulating genes cytotoxic T-lymphocyte-associated protein (CTLA)4, interleukin (IL)-13 and transforming growth factor (TGF)-β; the tissue remodeling genes matrix metalloprotease (MMP)1 and 9, tissue inhibitors of metalloproteases (TIMP)1 and 2, and the genes regulating endothelial function vascular endothelial growth factor (VEGF)1, angiopoietin (Ang)1, Ang 2, and platelet endothelial cell adhesion molecule (PECAM)-1. In contrast, transcription was only modestly decreased in the DEX pretreated pigs compared to PZQ alone, and only for TNF-α, IL-6, IFN-γ, TGF-β and Ang1. IL-10 was not affected by either ETN or DEX pretreatments. The degree of inflammation, assessed by semi-quantitative inflammatory scores, was modestly decreased in both ETN and DEX pretreated animals compared to PZQ treated pigs whereas cyst damage scores were moderately decreased only in cysts from DEX pretreated pigs. However, the proportion of cysts with EB extravasation was not significantly changed in ETN and DEX pretreated groups.

Conclusions/Significance

Overall, TNF-α blockade using ETN treatment modulated expression of a large variety of genes that play a role in induction and control of inflammation and structural changes. In contrast the number of inflammatory cells was only moderately decreased suggesting weaker effects on cell migration into the inflammatory capsules surrounding cysts than on release of modulatory molecules. Taken together, these data suggest that TNF-α blockade may provide a viable strategy to manage post-treatment pericystic inflammation that follows antiparasitic therapy for neurocysticercosis.

Infection of the brain with larvae of the tapeworm Taenia solium is called neurocysticercosis (NCC), a disease with varied and serious neurological symptoms. Therapy requires antiparasitic drugs and corticosteroids to prevent seizures caused by treatment due to inflammation around dying parasites. The gene expression of the proinflammatory molecule tumor necrosis factor alpha (TNF-α) is increased in NCC. We treated three groups of naturally infected pigs with an antiparasitic drug: one group was also pretreated with an anti-TNF-α inhibitor, the second one with a corticosteroid, and the third was not pretreated. All pigs were infused with Evans blue dye (EB), which leaks where the blood brain barrier is damaged by inflammation around cysts. We compared the expression of several genes involved in inflammation, healing and fibrosis and regulation of vascular function in tissues surrounding cysts. In inflamed samples showing leaked EB, the inhibition of TNF-α suppressed nearly all the genes assessed, and this suppression was significantly stronger than the moderate decrease caused by corticosteroid pretreatment on most of the genes. On microscopic examination, the inflammation observed was slightly decreased with both pretreatments in relation to the group that was not pretreated. We believe that the inflammatory route that includes TNF-α should be further explored in the search for better management of inflammation directed to degenerating cysts.

Neuropsychiatric disorders in patients with neurocysticercosis

INTRODUCTION

The purpose of this study was to explore the presence of neuropsychiatric disorders in patients with neurocysticercosis (NCC).

METHOD

Patients with untreated NCC (n = 45) and healthy controls (n = 45) underwent psychiatric and neuropsychological assessments.

RESULTS

The majority of patients in the NCC group (64.4%) had at least 1 psychiatric diagnosis, compared with a minority in the control group (31.1%). The frequency of neurocognitive disorders, and particularly dementia (major neurocognitive disorder), was significantly higher in the group of patients with NCC.

DISCUSSION

This study confirms the relationship between NCC and cognitive disorders.

[Racemose neurocysticercosis: Neuroimaging guides the diagnosis]

Neurocysticercosis is the leading cause of parasitosis of the central nervous system and acquired epilepsy in developing countries. The clinical manifestations of neurocysticercosis, especially its racemose variant, are pleomorphic and unspecific, characteristics that hinder the diagnosis and make it a challenge for the clinician.The objective of this report was to describe two cases of racemose neurocysticercosis in which neuroimaging led to the definitive diagnosis. The first case involved a patient with persistent headache and focal neurological signs. She required multiple paraclinical tests that led to the definitive diagnosis of racemose neurocysticercosis with secondary cerebral vasculitis. Despite medical and surgical treatment the patient died after multiple complications.The second case involved a patient with a history of neurocysticercosis, who consulted for chronic intractable vomiting. She required multiple paraclinical tests that led to the diagnosis of vomiting of central origin secondary to racemose neurocysticercosis and entrapment of the fourth ventricle. After medical and surgical treatment the patient showed slight improvement. In these two cases it was evident how proper interpretation of neuroimages is essential for the diagnosis of racemose neurocysticercosis.

Reduced Leukocyte Infiltration in Absence of Eosinophils Correlates with Decreased Tissue Damage and Disease Susceptibility in ΔdblGATA Mice during Murine Neurocysticercosis

Neurocysticercosis (NCC) is one of the most common helminth parasitic diseases of the central nervous system (CNS) and the leading cause of acquired epilepsy worldwide. NCC is caused by the presence of the metacestode larvae of the tapeworm Taenia solium within brain tissues. NCC patients exhibit a long asymptomatic phase followed by a phase of symptoms including increased intra-cranial pressure and seizures. While the asymptomatic phase is attributed to the immunosuppressive capabilities of viable T. solium parasites, release of antigens by dying organisms induce strong immune responses and associated symptoms. Previous studies in T. solium-infected pigs have shown that the inflammatory response consists of various leukocyte populations including eosinophils, macrophages, and T cells among others. Because the role of eosinophils within the brain has not been investigated during NCC, we examined parasite burden, disease susceptibility and the composition of the inflammatory reaction in the brains of infected wild type (WT) and eosinophil-deficient mice (ΔdblGATA) using a murine model of NCC in which mice were infected intracranially with Mesocestoides corti, a cestode parasite related to T. solium. In WT mice, we observed a time-dependent induction of eosinophil recruitment in infected mice, contrasting with an overall reduced leukocyte infiltration in ΔdblGATA brains. Although, ΔdblGATA mice exhibited an increased parasite burden, reduced tissue damage and less disease susceptibility was observed when compared to infected WT mice. Cellular infiltrates in infected ΔdblGATA mice were comprised of more mast cells, and αβ T cells, which correlated with an abundant CD8⁺ T cell response and reduced CD4⁺ Th1 and Th2 responses. Thus, our data suggest that enhanced inflammatory response in WT mice appears detrimental and associates with increased disease susceptibility, despite the reduced parasite burden in the CNS. Overall reduced leukocyte infiltration due to absence of eosinophils correlates with attenuated tissue damage and longer survival of ΔdblGATA mice. Therefore, our study suggests that approaches to clear NCC will require strategies to tightly control the host immune response while eradicating the parasite with minimal damage to brain tissue.

Eosinophils are known to mediate a protective response against several parasitic infections. This is largely accomplished by eosinophil degranulation (direct killing) and modulating effective adaptive immune responses. Consequently, eosinophils can also contribute to host pathology via a bystander effect. However, the outcome of infection varies depending upon the parasite species. In the case of neurocysticercosis (NCC), the role of eosinophils in disease progression has not been investigated despite the known eosinophilic response in patients. NCC is one of the most common parasitic diseases of the brain which is caused by the metacestode (larva) of the tapeworm Taenia solium. To determine the role of eosinophils in NCC disease outcome, we used a murine model of NCC in which wildtype (WT) or eosinophil deficient mice (ΔdblGATA) were infected intracranially with Mesocestoides corti, a cestode parasite related to T. solium. Our data show that murine NCC is characterized by a robust eosinophil response that correlates with lower parasite burden in the brain. Comparison of T cell response reveals a mixed Th1/Th2 in the WT brain, and ΔdblGATA mice showed a significant decrease in both population but in particular in the Th2 response. In addition, the strong eosinophil reaction observed in WT brains correlates with exacerbated pathology and increased morbidity. Thus, our study suggest that eosinophils act as a double-edged sword playing a role in controlling the infection but worsening the disease outcome by contributing to host pathology.

Antiepileptic drug therapy and recommendations for withdrawal in patients with seizures and epilepsy due to neurocysticercosis

INTRODUCTION

Neurocysticercosis (NCC) is a leading causes of secondary epilepsy worldwide. There is increasing evidence on the epileptogenic role of NCC, and the presence of edema, calcified scars, gliosis and hippocampal sclerosis support this phenomenon.

AREAS COVERED

We summarized principles of antiepileptic drug (AED) therapy as well as risk factors associated with seizure recurrence after AED withdrawal in patients with NCC. Expert commentary: First-line AED monotherapy is effective as a standard approach to control seizures in most NCC patients. Risks and benefits of AED withdrawal have not been systematically studied, and this decision must be individualized. However, a seizure-free period of at least two years seem prudent before attempting withdrawal. Risk factors for seizure recurrence after AED withdrawal include a history of status epilepticus, poor seizure control during treatment, neuroimaging evidence of perilesional gliosis, hippocampal sclerosis and calcified lesions, as well as persistence of paroxysmal activity in the EEG.

Longer epilepsy duration and multiple lobe involvement predict worse seizure outcomes for patients with refractory temporal lobe epilepsy associated with neurocysticercosis

OBJECTIVE

To investigate the surgical outcomes of temporal lobe epilepsy associated with hippocampal sclerosis (TLE-HS) and neurocysticercosis (NCC).

METHODS

A retrospective investigation of patients with TLE-HS was conducted in a tertiary center.

RESULTS

Seventy-nine (62.2%), 37 (29.1%), 6 (4.7%), and 5 (3.9%) patients were Engel class I, II, III, and IV, respectively. Fifty-two (71.2%) patients with epilepsy durations ≤ 10 years prior to surgery were seizure-free 1 year after the operation compared to 27 (50.0%) patients with epilepsy durations > 10 years (p = 0.0121). Forty-three (72.9%) patients with three or fewer lobes affected by NCC were seizure-free one year after the operation, and 36 (52.9%) patients with more than three involved lobes were seizure-free after surgery (p = 0.0163).

CONCLUSIONS

Longer epilepsy durations and multiple lobe involvement predicted worse seizure outcomes in TLE-HS plus NCC patients.

Clinical management of infectious cerebral vasculitides

A wide range of infections (virus, bacteria, parasite and fungi) may cause cerebral vasculitides. Headache, seizures, encephalopathy and stroke are common forms of presentation. Infection and inflammation of intracranial vessels may cause pathological vascular remodelling, vascular occlusion and ischemia. Vasculitis in chronic meningitis may cause ischemic infarctions, and is associated with poor outcome. Appropriate neuroimaging (CT-angiography, MR-angiography, conventional 4-vessel angiography) and laboratory testing (specific antibodies in blood and CSF, CSF culture and microscopy) and even brain biopsy are needed to quickly establish the aetiology. Enhancement of contrast, wall thickening and lumen narrowing are radiological signs pointing to an infectious vasculitis origin. Although corticosteroids and prophylactic antiplatelet therapy have been used in infectious cerebral vasculitis, there are no randomized clinical trials that have evaluated their efficacy and safety. Stable mycotic aneurysms can be treated with specific antimicrobial therapy. Endovascular therapy and intracranial surgery are reserved for ruptured aneurysms or enlarging unruptured aneurysms.

Alternative energy production pathways in Taenia crassiceps cysticerci in vitro exposed to a benzimidazole derivative (RCB20)

Biochemical studies of benzimidazole derivatives are important to determine their mode of action and activity against parasites. The lack of antihelminthic alternatives to treat parasitic infections and albendazole resistance cases make the search for new antiparasitary drugs of utmost importance. The 6-chloro-5-(1-naphthyloxy)-2-(trifluoromethyl)-1H-benzimidazole (RCB20) is a benzimidazole derivative with promising effect. This study evaluated the effect of different concentrations of RCB20 in the alternative energetic pathway of in vitro Taenia crassiceps cysticerci. The parasites were in vitro exposed to 6·5 and 13 µm of RCB20 and albendazole sulfoxide (ABZSO). The quantification of acetate, acetoacetate, β-hydroxybutyrate, fumarate and propionate was performed by high-performance liquid chromatography. The quantification of urea, creatinine and total proteins was performed by spectrophotometry. The increase in β-hydroxybutyrate reflects the enhancement of the fatty acid oxidation in the treated groups. Volatile fatty acids secretion, acetate and propionate, was increased in the treated groups. The secretion mechanisms of the treated parasites were impaired due to organic acids increased concentrations in the cysticerci. It is possible to conclude that the metabolic effect on alternative energetic pathways is slightly increased in the parasites treated with RCB20 than the ones treated with ABZSO.

[Disseminated cysticercosis: report of three cases in Togo]

We report 3 cases of disseminated cysticercosis (DC) in adult male subjects in Togo. All had consulted in dermatology for asymptomatic subcutaneous nodules. The diagnosis was confirmed by histology of a resected nodule. Computed tomography allowed us to bring out the widespread dissemination of cysticerci. The skin, brain, muscle, eye, thyroid, and pleura were the affected organs. Treatment was based on albendazole and betamethasone, with adverse side effects in 2 of our 3 patients. Our 3 observations seem to be the first of their kind in Togo. The mechanism of contamination in these disseminated forms is not yet elucidated, however ingesting a gravid proglottis could be the basis of the widespread dissemination of cysticerci in the body. No consensus has yet been established in the treatment of DC and the management should follow the guideline for treatment of neurocysticercosis and ocular cysticercosis.

Genome analysis of Excretory/Secretory proteins in Taenia solium reveals their Abundance of Antigenic Regions (AAR)

Excretory/Secretory (ES) proteins play an important role in the host-parasite interactions. Experimental identification of ES proteins is time-consuming and expensive. Alternative bioinformatics approaches are cost-effective and can be used to prioritize the experimental analysis of therapeutic targets for parasitic diseases. Here we predicted and functionally annotated the ES proteins in T. solium genome using an integration of bioinformatics tools. Additionally, we developed a novel measurement to evaluate the potential antigenicity of T. solium secretome using sequence length and number of antigenic regions of ES proteins. This measurement was formalized as the Abundance of Antigenic Regions (AAR) value. AAR value for secretome showed a similar value to that obtained for a set of experimentally determined antigenic proteins and was different to the calculated value for the non-ES proteins of T. solium genome. Furthermore, we calculated the AAR values for known helminth secretomes and they were similar to that obtained for T. solium. The results reveal the utility of AAR value as a novel genomic measurement to evaluate the potential antigenicity of secretomes. This comprehensive analysis of T. solium secretome provides functional information for future experimental studies, including the identification of novel ES proteins of therapeutic, diagnosis and immunological interest.