Neurocysticercosis: Current Perspectives on Diagnosis and Management

Development of point-of-care immunodiagnostic test for Taenia solium cysticercosis in pigs

Cysticercosis, caused by the larval stage of Taenia solium, is a major zoonotic parasitic disease with a global impact, heightened by immigration and transboundary activities. Recognizing its importance, the World Health Organization has prioritized eliminating taeniasis/cysticercosis by 2030, designating it as a priority neglected tropical disease (NTD). Accurate diagnosis is essential for effective disease control, yet traditional methods often fall short due to low sensitivity of the test and the need for specialized laboratory setups. This study focuses on developing a recombinant Ag2 (rAg2)-based dot blot assay to detect T. solium cysticercosis in pigs. The rAg2 antigen was successfully expressed and purified, with immunoreactivity confirmed against sera from naturally infected pigs. The dot blot test evaluated against serological gold-standard enzyme-linked immunotransfer blot (EITB) assay, demonstrated preliminary laboratory sensitivity (89 %, 95 % CI: 68.6-97.1) and specificity (100 %, 95 % CI: 97.6 - 100), highlighting its potential as a reliable alternative diagnostic method. Cost-effectiveness and minimal laboratory requirements make it particularly suited for field use in resource-limited settings.

Immunologic Profiling of CSF in Subarachnoid Neurocysticercosis Reveals Specific Interleukin-10-Producing Cell Populations During Treatment

BACKGROUND AND OBJECTIVES

Subarachnoid neurocysticercosis (SANCC) is the most severe form of Taenia solium CNS infection and accounts for the majority of neurocysticercosis-associated mortality. Inflammation is important in the treatment of SANCC because overactivity can lead to serious complications, but excessive suppression may be counterproductive toward parasite eradication. A relative abundance of CSF IL-10 to IL-12 has been associated with increased treatment duration for patients with SANCC, suggesting that IL-10 plays an important role in this disease process. To better understand SANCC immunology and the major sources of IL-10 during anthelmintic treatment, we took an unbiased and comprehensive approach to phenotype the immune cell populations in the CSF and peripheral blood of patients with SANCC.

METHODS

Eight samples of CSF cells collected from 5 patients with SANCC during treatment were evaluated using single-cell RNA sequencing. Matched CSF and peripheral blood mononuclear cells from 4 patients were assessed using flow cytometry. Staining for extracellular and intracellular markers allowed for the characterization of IL-10-producing T cells.

RESULTS

The CSF during SANCC contains a diversity of immune cell populations including multiple myeloid and lymphoid populations. Although there were changes in the composition of CSF cells during treatment, the largest population at both early and late time points was CD4+ T cells. Within this population, we identified 3 sources of IL-10 unique to SANCC CSF compared with controls: natural regulatory T cells (nTregs), induced regulatory T cells (iTregs), and Th17 cells. The abundance and phenotype of these IL-10-producing populations differed between CSF and blood in patients with SANCC, but iTregs were the single most productive population in the CSF. During treatment, these IL-10 producers persisted in consistent proportions despite decreases in parasite antigen over time.

DISCUSSION

This profile of immune cell populations in the CSF provides a comprehensive blueprint of the local and systemic immunology associated with SANCC. The identification of IL-10-producing cells in the CSF and peripheral blood deepens our understanding of the immunosuppressive phenotype that deters SANCC treatment success. Finally, the discovery that these IL-10 producers persist throughout treatment highlights the endurance of these populations in the CNS.

Concordance between a New Rapid Point-Of-Care Assay and Standard ELISA in the Detection of Cysticercosis Antigens in Urine

Neurocysticercosis is a parasitic disease of major public health importance. Definitive diagnosis requires neuroimaging, which is typically unavailable in rural impoverished regions of endemicity. Screening immunoassays can support diagnosis in this setting by identifying individuals most likely to have severe forms of disease for referral to imaging. Urine sampling is convenient, painless, and generally well accepted. We developed a rapid point-of-care (POC) assay to detect urinary antigens and assessed concordance with a standard antigen ELISA (Ag-ELISA), both using monoclonal antibodies TsW8/TsW5. From 28,145 stored community samples with Ag-ELISA results, we selected 843 for comparison, 281 each from nonreactive (ratio <1), reactive-below-cutoff (ratio 1:3), and positive (ratio ≥3) samples. Overall agreement was 73.6%, with strong agreement observed in the nonreactive (280/281, 99.6%) and positive (255/281, 90.8%) groups. This affordable noninvasive POC test can be applied to identify individuals in the community most at risk of developing severe disease.

Neurocysticercosis and cognitive impairment among people with epilepsy in Taenia solium endemic regions of rural southern Tanzania: A hospital-based cross-sectional study in mental health clinics of selected sites in Tanzania

BACKGROUND

Epilepsy poses a significant public health problem in many parts of the world. The majority of people with epilepsy (PWE) are from low-income and middle-income countries (LMICs). Taenia solium neurocysticercosis (NCC) is estimated to cause 30% of preventable epilepsy in PWE in areas of T. solium endemicity. This study was conducted to assess the prevalence of NCC in PWE, evaluate the presence of cognitive impairment in PWE and assess potentially contributing factors.

METHODS

PWE were recruited within a mental health clinic-based cross-sectional study in rural Southern Tanzania. PWE underwent a detailed neurological examination, including mental state, and a blood sample was collected for T. solium cysticercosis (CC) serology testing. Patients who were serologically positive for CC and those detected to have prominent neurological deficits apart from epilepsy were invited to receive a cerebral computed tomography (CT) examination.

RESULTS

Out of the 223 people with epilepsy (PWE) recruited, 221 underwent clinical examination. Among these, 26 (11.8 %) had cognitive impairment, and 2 had neurological signs or symptoms without cognitive impairment. Twenty-five of the 223 PWE (11.2 %) tested positive for CC, of which 4 had cognitive impairment. One hundred and ninety-eight (88.8 %) tested negative for CC, of which 22 had cognitive impairment. A total of 36 participants underwent CT scans, with 18 testing positive and 18 testing negative for CC. Of the 36 who had CT scans, 8 (22.2 %) were diagnosed with NCC; 7 were CC positive, and 1 was CC negative; only the latter had cognitive impairment. Multivariate logistic regression confirmed that cognitive impairment in PWE was 8.62 times higher for Kongwa participants than Chunya, with a statistically significant association (95 % CI: 1.75, 156; p = 0.037). Additionally, having and education was associated with a 91 % reduction in the odds of cognitive impairment (OR = 0.09) compared to no education, which was also statistically significant (95 % CI: 0.01, 0.33; p = 0.002). There was no association between cognitive impairment and NCC.

CONCLUSION

Our study found a 22.2 % prevalence of NCC among PWE. Cognitive impairment was present in 11.8 % of PWE but was not significantly associated with NCC. Socioeconomic and educational factors may play a larger role in cognitive impairment among PWE.

Efficiency of Cysticidal Therapy Impacted by the Host's Immune Response in Neurocysticercosis Patients

Neurocysticercosis (NCC) is a neurological condition caused by the presence of cysts of Taenia solium in the brain, which manifests with a range of clinical symptoms. The severity of NCC and its prognosis following anti-helminth drug (AHD) treatment are closely linked to peripheral and local inflammation. The study aimed to analyse the efficiency of cysticidal therapy impacted by the host's immune response in NCC patients. A total of 104 patients were screened in this study, and blood samples were collected from 30 patients. The follow-up samples within 3 to 6 months of treatment were collected. Patients were categorised as Responder (R) and Non-Responder (NR). Cytokines IL-6, IL-10, IFN-γ and TNF-α were estimated using ELISA kits in PBMC cells. T0 is the time point before the AHD treatment begins, and T1 is between 3 to 6 months after the treatment starts. The responder patients showed significantly lower IL-10 and IL-6 levels in the supernatants at T0 as compared to T1, while in non-responder patients, IL-10 and IL-6 levels were higher at T0 as compared to T1. The IFN-γ and TNF-α levels were found to be higher in the supernatants at T0 as compared to T1 in both the responder and non-responder patients. These observations imply that these cytokines might have an impact on the efficacy of AHD treatment in NCC patients.

Neurocysticercosis in a Nigerian woman -missed diagnosis of a neglected disease and surgical management

Neurocysticercosis is a rarely diagnosed but significant clinical problem from infestation with taenia solium. It occurs as a result of ingestion of infested pork and the mode of transmission is usually feco-oral. It is commonly associated with non-specific neurologic manifestations expected of intracranial space-occupying lesions with its most common neurological presentation being seizures. However, its diagnosis without seizure is rarely reported. We report a recent experience in this regard and outcome of this disease which was inadvertently managed surgically. A good history and high index of suspicion especially in developing and low socioeconomic region is helpful for diagnosis in the presence of appropriate radiological findings. Prognosis is good when treatment is tailored to well selected cases. Treatment options include medical with or without surgical removal of encapsulated cyst. A high index of suspicion will be helpful in making appropriate diagnosis and proper management of this disease.

Unmasking a Hidden Culprit: Neurocysticercosis, an Overlooked Cause of Acquired Epilepsy

Neurocysticercosis (NCC) is a common parasitic brain infestation caused by the ingestion of Taenia solium eggs, predominantly in developing countries. In this report, we presented the case of a 44-year-old woman who exhibited stroke symptoms and had a decade-long history of recurrent headaches and epilepsy. At presentation, a non-contrast computed tomography scan of the brain was performed and revealed hypodense oval lesions and calcified cysts in both cerebral hemispheres, strongly indicative of NCC. The patient responded positively to treatment with dexamethasone, albendazole, and carbamazepine. This case study underscores the importance of neuroimaging in investigating patients with neurological conditions like epilepsy, especially in developing countries. Early diagnosis and effective treatment are crucial in preventing and controlling NCC, reducing its impact on public health.

Repurposing mebendazole against triple-negative breast cancer CNS metastasis

PURPOSE

Triple-negative breast cancer (TNBC) often metastasizes to the central nervous system (CNS) and has the highest propensity among breast cancer subtypes to develop leptomeningeal disease (LMD). LMD is a spread of cancer into leptomeningeal space that speeds up the disease progression and severely aggravates the prognosis. LMD has limited treatment options. We sought to test whether the common anti-helminthic drug mebendazole (MBZ) may be effective against murine TNBC LMD.

METHODS

A small-molecule screen involving TNBC cell lines identified benzimidazoles as potential therapeutic agents for further study. In vitro migration assays were used to evaluate cell migration capacity and the effect of MBZ. For in vivo testing, CNS metastasis was introduced into BALB/c athymic nude mice through internal carotid artery injections of brain-tropic MDA-MB-231-BR or MCF7-BR cells. Tumor growth and spread was monitored by bioluminescence imaging and immunohistochemistry. MBZ was given orally at 50 and 100 mg/kg doses. MBZ bioavailability was assayed by mass spectrometry.

RESULTS

Bioinformatic analysis and migration assays revealed higher migratory capacity of TNBC compared to other breast cancer subtypes. MBZ effectively slowed down migration of TNBC cell line MDA-MB-231 and its brain tropic derivative MDA-MB-231-BR. In animal studies, MBZ reduced leptomeningeal spread, and extended survival in brain metastasis model produced by MDA-MB-231-BR cells. MBZ did not have an effect in the non-migratory MCF7-BR model.

CONCLUSIONS

We demonstrated that MBZ is a safe and effective oral agent in an animal model of TNBC CNS metastasis. Our findings are concordant with previous efforts involving MBZ and CNS pathology and support the drug's potential utility to slow down leptomeningeal spread.

Neurocysticercosis: A Challenging Case in New Mexico

Neurocysticercosis, a parasitic infection caused by the larvae of Taenia solium, presents a diagnostic challenge, particularly in non-endemic regions. This case report evaluates the intricacies of diagnosing neurocysticercosis in a 62-year-old male presenting with an intractable headache and altered mental status, initially confounded by the absence of an exposure history. Despite lacking typical risk factors, including immunocompromise or HIV infection, his travel history to an endemic area prompted a rigorous clinical work-up. Imaging studies revealed characteristic ring-enhancing lesions indicative of neurocysticercosis, while further serological tests yielded mostly equivocal results. Infectious disease consultation and workup helped confirm a probable diagnosis. Prompt initiation of anti-helminthic therapy led to marked clinical improvement. This case underscores the importance of considering neurocysticercosis in the differential diagnosis of intracranial lesions, especially in regions with Hispanic populations, and advocates for increased awareness and research to enhance timely identification and management, thereby improving patient outcomes.

Repurposing mebendazole against triple-negative breast cancer leptomeningeal disease

Purpose

Triple-negative breast cancer (TNBC) is an aggressive subtype that often metastasizes to the brain. Leptomeningeal disease (LMD), a devastating brain metastasis common in TNBC, has limited treatment options. We sought to test whether the common anti-helminthic drug mebendazole (MBZ) may be effective against murine TNBC LMD.

Methods

A small-molecule screen involving TNBC cell lines identified benzimidazoles as potential therapeutic agents for further study. In vitro migration assays were used to evaluate cell migration capacity and the effect of MBZ. For in vivo testing, LMD was introduced into BALB/c athymic nude mice through internal carotid artery injections of brain-tropic MDA-MB-231-BR or MCF7-BR cells. Tumor growth and spread was monitored by bioluminescence imaging. MBZ was given orally at 50 and 100 mg/kg doses. MBZ bioavailability was assayed by mass spectrometry.

Results

Bioinformatic analysis and migration assays revealed higher migratory capacity of TNBC compared to other breast cancer subtypes. MBZ effectively slowed down migration of TNBC cell line MDA-MB-231 and its brain tropic derivative MDA-MB-231-BR. In animal studies, MBZ reduced tumor growth and extended survival in the LMD model produced by MDA-MB-231-BR cells. MBZ did not have an effect in the non-migratory MCF7-BR model.

Conclusions

We demonstrated that MBZ is a safe and effective oral agent in an animal model of TNBC LMD. Our findings are concordant with previous efforts involving MBZ and central nervous system pathology and further support the drug's potential utility as an alternative therapeutic for TNBC LMD.

The Microbiome and Infectious Diseases

Our perception of microbes has considerably changed since the recognition of their pathogenic potential in the 19th century. The discovery of antibiotics and their subsequent widespread adoption have substantially altered the landscape of medicine, providing us with treatment options for many infectious diseases and enabling the deployment of previously risky interventions (eg, surgical procedures and chemotherapy), while also leading to the rise of AMR. The latter is commonly viewed as the predominant downside of antibiotic use. However, with the increasing recognition that all metazoan organisms rely on a community of microbes (the microbiota) for normal development and for most physiologic processes, the negative impacts of antibiotic use now extend well beyond AMR. Using the iceberg as a metaphor, we argue that the effects of antibiotics on AMR represent the tip of the iceberg, with much greater repercussions stemming from their role in the rise of so-called noncommunicable diseases (including obesity, diabetes, allergic and autoimmune diseases, neurodevelopmental disorders, and certain cancers). We highlight some of the emerging science around the intersection of the microbiome, antibiotic use, and health (including biological costs and future therapeutic avenues), and we advocate a more nuanced approach in evaluating the impacts of proposed antibiotic use, especially in the setting of preexposure and postexposure prophylaxis.

Development and validation of a predictive model assessing the risk of seizure recurrence in children with neurocysticercosis

INTRODUCTION

Neurocysticercosis (NCC) is a significant factor contributing to the incidence of seizures in developing countries. While numerous studies have investigated the recurrence of seizures in NCC, their reliability is often limited.

METHODS

We assessed the socio-demographic, clinical, and neuroimaging details of 161 children with seizures caused by NCC. We monitored them for seizure recurrence over a 6-month follow-up period. We divided the children into two groups: those with seizure recurrence and those without. Subsequently, we identified predictive factors associated with seizure recurrence through univariate analysis, followed by multivariate binary logistic regression. We evaluated the prognostic model for discrimination and calibration and then internally validated it using the bootstrap method.

RESULTS

A total of 23 children experienced breakthrough seizures. In multivariate analysis, the presence of epileptiform abnormalities in electroencephalogram (EEG), more than 5 NCC lesions, the presence of perilesional edema greater than 2 cm in maximum dimension, and a cluster of seizures before presentation were significantly associated with seizure recurrence (p < 0.05). These factors were included in the final NEPC (Number of NCC lesions, Epileptiform EEG abnormality, Perilesional edema, and Cluster of seizures) score. The final model exhibited good discrimination (AUC = 89.1 %; 95 % CI=80.5-95.3 %, p < 0.001) and calibration (p = 0.54). A score of 4 appeared to be the optimal threshold for discriminating between individuals with and without seizure recurrence, with sensitivity and specificity values of 85 % and 87 %, respectively. Interrater reliability was very strong between two pediatric neurologists and strong between a pediatric neurologist and a pediatric neurology trainee resident (k = 0.92 and 0.86, respectively).

CONCLUSION

The NEPC score demonstrates good sensitivity and specificity in predicting seizure recurrence in pediatric children with NCC.

Emerging and Re-Emerging Parasitic Infections of the Central Nervous System (CNS) in Europe

In a rapidly evolving global landscape characterized by increased international travel, migration, and ecological shifts, this study sheds light on the emergence of protozoal and helminthic infections targeting the central nervous system (CNS) within Europe. Despite being traditionally associated with tropical regions, these infections are progressively becoming more prevalent in non-endemic areas. By scrutinizing the inherent risks, potential outcomes, and attendant challenges, this study underscores the intricate interplay between diagnostic limitations, susceptibility of specific population subsets, and the profound influence of climate fluctuations. The contemporary interconnectedness of societies serves as a conduit for introducing and establishing these infections, warranting comprehensive assessment. This study emphasizes the pivotal role of heightened clinician vigilance, judicious public health interventions, and synergistic research collaborations to mitigate the potential consequences of these infections. Though rare, their profound impact on morbidity and mortality underscores the collective urgency required to safeguard the neurological well-being of the European populace. Through this multifaceted approach, Europe can effectively navigate the complex terrain posed with these emergent infections.

Insights into the diagnosis, vaccines, and control of Taenia solium, a zoonotic, neglected parasite

Taenia solium taeniasis/cysticercosis (TSTC) is a foodborne, zoonotic neglected tropical disease affecting predominately low- and middle-income countries. Humans are definitive hosts for T. solium, whereas pigs act as intermediate hosts. Taeniasis, i.e. intestinal infection with adult T. solium in the human host, occurs through ingestion of undercooked pork infected with the larval stage (porcine cysticercosis, PCC). Human cysticercosis occurs after humans ingest T. solium eggs, acting as accidental intermediate hosts. Migration of cysticerci to the human brain results in neurocysticercosis (NCC), manifesting in a variety of clinical symptoms, most notably epilepsy. NCC is the leading cause of acquired epilepsy cases in endemic areas. PCC results in reduced pork value because of condemnation or the risk of condemnation of the meat. Available serological diagnostic tests for porcine and human cysticercosis are characterized by low sensitivity and are not cost-effective. An effective vaccine for T. solium cysticercosis in pigs has been developed, although it is not yet commercially available in all endemic countries, and still no vaccine is available for use in humans. This primer highlights the recent development in the field of diagnostic tests and vaccine production and explores possible strategies for future control and eradication of T. solium. In the absence of highly specific diagnostic tests and human vaccines, treatment of infected pigs and tapeworm carriers and prevention of disease transmission remain the principal means to interrupt the zoonotic cycle of T. solium in endemic countries.

Monetary burden of neurocysticercosis on a hospitalized population in Muli County, China

Neurocysticercosis (NCC) is a potentially life-threatening condition caused by the zoonotic cestode, Taenia solium. Pigs are the typical intermediate hosts for T. solium but humans can become infected and develop NCC upon ingesting parasite eggs that are shed in the feces of an infected person. The objective of this study was to estimate the monetary burden of neurocysticercosis (NCC) on hospitalized patients from Muli County, China. Muli is an agricultural county in Liangshan Prefecture, Sichuan Province, China where pigs are raised and the zoonotic cestode, Taenia solium, is endemic. Demographic and treatment data were collected from the Muli County Health Insurance Department on hospitalized individuals with an NCC diagnosis between 2014 and 2021. These patients represent residents of Muli County that purchased health insurance and received treatment in a public hospital in Sichuan Province. Hospital costs were converted from Chinese renminbi (RMB) to United States dollars (US$) for month and year of hospitalization and adjusted for inflation. Individuals with missing hospital information were excluded from analysis. For indirect costs, annual average salary for Liangshan Prefecture working-age adults was obtained to calculate productivity losses based on number of hospitalization days and travel days to and from the hospital. Transportation costs were evaluated based on estimated bus fare to and from the hospital. Out of 70 patients identified from 2014 to 2021, 68 had complete records, of which 47.1% were male (n = 33) and the median age at first hospitalization was 34 years. Total estimated cost for these patients was US$228,341.98. Direct costs contributed 62.5% (US$142,785.25) and indirect costs were 37.5% (US$85,556.73) of the total cost. The estimated median cost per case was US$2,078.69. Individuals with a single hospitalization (n = 41) cost a median of US$1,572.03 and those with multiple hospitalizations (n = 27) cost a median of US$4,169.95. The median total cost per NCC case was 18.6% of the average wage for a Liangshan Prefecture resident in 2021. While the study was limited to those with insurance coverage, monetary burden on the local population is likely substantial. Public health policies aimed at reducing transmission should be implemented to decrease the economic burden of NCC on this region.

Intraventricular migration of fourth ventricular neurocysticercosis: an unusual complication during endoscopic surgery

A boy in his middle childhood presented with intermittent episodes of headache with vomiting for 6 months. Plain CT of the head and MRI of the brain revealed fourth ventricular cysticercal cyst with acute obstructive hydrocephalus. Endoscopic excision of the cyst was done along with endoscopic third ventriculostomy and septostomy with external ventricular drain placement. Although we were able to decompress the cysticercal cyst, unfortunately, the cyst got slipped from the grasper leaving the grasped cyst wall in the tooth of the grasper. Through this case report, we want to highlight that such a complication could also happen during neuroendoscopic cysticercal cyst removal and how we dealt with it. Our patient was discharged neurologically intact and was symptom free on follow-up.

Global research on cysticercosis and neurocysticercosis: A bibliometric analysis

Background

Cysticercosis is a parasitic infection caused by the larval stage Taenia solium. As a neglected tropical disease that is also difficult to diagnose, cysticercosis constitutes an important public health and research challenge. To characterize the development of research on cysticercosis and neurocysticercosis, considering the level of scientific evidence provided and the contribution of different countries to research, according to their endemic nature and their income level.

Methods

Indexed publications on cysticercosis and neurocysticercosis were retrieved from the MEDLINE database, and the evolution of scientific production and the topic areas addressed in the body of research were analyzed.

Results

A total of 7,860 papers published between 1928 and 2021 were analyzed. The volume of annual publications increased over time, standing at over 200 documents/year since 2010. Case studies constitute the main study design (27.4% of the documents with available information, n = 2,155), with fewer studies that provide the highest levels of scientific evidence, such as clinical studies (1.9%, n = 149) or systematic reviews (0.8%, n = 63). The most productive journals belong to the Parasitology and Tropical Medicine categories. Although the USA is the most productive country (n = 2,292), countries where Tenia solium is endemic, such as India (n = 1,749), Brazil (n = 941) and Peru (n = 898) also stand out, as does Mexico (n = 1,414). However, other endemic countries in Latin America and sub-Saharan Africa show little participation in the research. The level of international collaboration by country is very uneven, with some countries presenting very low values, such as India (9.9% of documents in international collaboration) or Brazil (18.7%); while there is evidence of intense international collaboration in countries like Peru (91.3%), Tanzania (88.2%) or Kenya (93.1%). Research output has coalesced in three thematic clusters: basic research in animals; parasitism, animal health, and zoonoses; and the diagnosis and therapeutic approach in diseases associated with cysticercosis and neurocysticercosis.

Conclusions

The generation of knowledge on cysticercosis presents different features from other areas of research, such as the outstanding contribution of only some endemic countries; and the relevance of comprehensive approaches to research (animal and human health). Studies that provide higher levels of scientific evidence should be promoted, as should research in endemic areas.

Acute reversible monoparesis in multiple neurocysticercosis: A case report and review of literature

Focal neurological deficit like monoparesis due to cortical lesions is a rare entity. In spite of the common presentations like seizures and headaches in neurocysticercosis, occurrence of reversible monoparesis is an atypical phenomenon. Even in the absence of infarct or hemorrhages, manifestation of neural deficit due to compressive effect only is an interesting finding. And on top of that, reversible nature of the deficit in space occupying lesion is a rare occurrence in the existing literature. Here, we describe a known case of neurocysticercosis with reversible acute monoparesis secondary to multiple neurocysticercosis. The variations with which neurocysticercosis can present broaden our understanding in its pathophysiology and management protocol.