Neurocysticercosis in the United States

Disseminated Neurocysticercosis With Intraventricular and Cisternal Extension Without Hydrocephalus: A Case Report

Neurocysticercosis, a leading cause of acquired epilepsy, can present as disseminated disease with widespread cystic lesions. A 33-year-old male with seizures and weakness showed radiologically confirmed neurocysticercosis. Treatment with steroids, antiparasitics, and antiseizure medication led to improvement. Early diagnosis and public health measures are crucial to reducing the burden.

Repair capacity of Taenia solium extraparenchymal cysts: radiological and in vitro evidence

Extraparenchymal neurocysticercosis (EP-NC) responds poorly to anthelmintic treatment. Several factors are involved in this low responsiveness, including the host's heterogeneous immune response and the ability of the parasite to evade it. In this study, we present radiological and in vitro findings that demonstrate that Taenia solium cysts have the capacity to repair from injuries. Six patients (three with cases of subarachnoid, two with cases of intraventricular, and one with a case of mixed subarachnoid and intraventricular cysts) presented with neurological complaints and underwent either medical or surgical treatment. Follow-up magnetic resonance imaging (MRI) showed apparent resolution of the cysts. However, months later (10-56) new MRI scans revealed cysts at the same sites observed before treatment. Cysts surgically removed were maintained in RPMI-1640 medium supplemented with 10% fetal bovine serum. Monthly assessments demonstrated the growth of the parasites and the release of HP-10. Our findings demonstrate the ability of T. solium extraparenchymal cysts to grow and repair themselves. This capacity is likely another factor involved in the disease's poor treatment response.

Proceedings from the CIHLMU International Health Symposium 2023: "One Health Approach to Neglected Tropical Diseases"

Neglected tropical diseases (NTDs) are a group of 20 conditions that affect impoverished communities and disproportionately impact women and children in tropical areas. The symposium aimed to raise awareness of NTDs and explore the One Health approach as well as actions needed to successfully combat NTDs. It featured four presentations and two panel discussions. The presentations covered topics such as the "Burden of NTDs in Low-and middle-income countries", "Challenges in the prevention and control of NTDs: Schistosomiasis", "One health action needed to address NTDs: the case of Neurocysticercosis", and "The success of one health intervention in the fight against Trachoma in Kenya". All presenters emphasized the crucial role of the One Health integrated approach in effectively and sustainably preventing NTDs.

Neurological disorders provoked by head and neck movement

Neurologists encounter a range of neurological disorders triggered by head and neck movement, reflecting an array of underlying pathologies and producing diverse symptoms. This article provides a practically orientated review of 14 disorders and how to diagnose and manage them, including common disorders such as benign paroxysmal positional vertigo and uncommon entities such as arterial compression syndromes leading to stroke or syncope, mobile intraventricular masses and medication withdrawal states. The article considers atypical scenarios including unusual manifestations and important mimics and discusses controversial entities, as well as the risk of misattributing symptoms based on incidental imaging abnormalities. Guidelines are referenced where they exist, while in rarer situations, approaches taken in published cases are described, with the acknowledgement that management decisions are at the clinician's discretion.

Oxidative Stress in the Murine Model of Extraparenchymal Neurocysticercosis

Oxidative stress is associated with several infectious diseases, as well as the severity of inflammatory reactions. The control of inflammation during parasite destruction is a target of neurocysticercosis treatment, as inflammation is strongly related to symptom severity. In this study, we investigated the presence of malondialdehyde and protein carbonyl, two by-products of reactive oxygen species (ROS), in an experimental model of extraparenchymal neurocysticercosis. Twenty male and twenty female rats were inoculated with 50 cysts of Taenia crassiceps in the subarachnoid space of the cisterna magna. Ten animals (five males and five females) were used as controls. Three months after inoculation, their brains were harvested for oxidative stress and histological assessments. Infected animals had higher scores for inflammatory cell infiltrates, malondialdehyde, and protein carbonyl. These results encourage future efforts to monitor oxidative stress status in neurocysticercosis, particularly in the context of controlling inflammation.

Surgical management of intraventricular neurocysticercosis: Two cases treated through transcallosal interhemispheric approach

Background

Cysticercosis, caused by the larval stage of Taenia solium, is a prevalent parasitic infection affecting the central nervous system, primarily in low-income countries. Surgical intervention becomes necessary when cysticercosis manifests within the ventricular system, with endoscopic techniques increasingly preferred over traditional microsurgical methods due to lower risks and morbidity. However, the microsurgical transcallosal approach, although effective, is infrequently used due to its associated high morbidity.

Case Description

We present two cases of multiple intraventricular neurocysticercosis treated through an open microsurgical technique using a transcallosal interhemispheric approach. Patient 1, a 56-year-old male, presented with severe headaches persisting for 6 months, while Patient 2, a 54-year-old male, experienced a sudden decrease in consciousness. Both patients exhibited typical magnetic resonance imaging characteristics indicative of intraventricular neurocysticercosis, leading to the decision for surgical resection.

Conclusion

Despite the transcallosal approach's decreased popularity due to associated risks, we achieved relatively good outcomes with minimal morbidity in both cases. Our experience highlights the importance of considering microsurgical approaches, particularly in facilities lacking endoscopic instrumentation, for the effective management of intraventricular neurocysticercosis. Compliance with postoperative medical therapy remains crucial to prevent recurrence.

Neurocysticercosis Presenting as Migraine in the United States

BACKGROUND Cysticercosis is a condition caused by infection with the larval form of Taenia solium, a pork tapeworm that uses pigs as an intermediate host. Humans become infected when they ingest water or food contaminated with tapeworm cysts. Cysticercosis is increasing in frequency in developed countries due to increased access to travel. Neurocysticercosis occurs when Taenia solium cysts embed within the nervous system. The clinical presentation of neurocysticercosis ranges from asymptomatic to life-threatening, largely depending on the brain parenchymal involvement. The diagnosis is typically made with a combination of clinical evaluation, serology, and neuroimaging. Treatment for parenchymal neurocysticercosis may involve anthelmintic agents, symptomatic agents, surgery, or a combination of methods. CASE REPORT A 52-year-old man with a medical history of migraine headaches, complicated type 2 diabetes mellitus, and obesity presented with a 4-month change in his migraines becoming severe, worse over his occiput bilaterally, and unresponsive to abortive therapy. His exposure history was unremarkable except for a habit of eating undercooked bacon, by which he would have developed neurocysticercosis via autoinfection. Neuroimaging and serology confirmed a diagnosis of neurocysticercosis and he was treated accordingly with antiparasitic and anti-inflammatory medications. CONCLUSIONS This presentation is nonspecific and can easily be overlooked, especially if there is an underlying known neurological condition such as migraine. This case illustrates that neurocysticercosis should be considered when an existing neuropathological condition displays a change in presentation or requires a change in therapeutic management, even without obvious risk factors.

Neurocysticercosis: The duration of its preclinical phase relies on the parasite location

OBJECTIVES

Neurocysticercosis (NC) is a heterogeneous disease particularly in terms of response to treatment and prognosis. Parasite localization is one of the main factors involved in this heterogeneity. In this study we aim to determine whether differences in the duration of the preclinical phase associated with parasite location, could contribute to said heterogeneity.

METHODS

Ninety-nine patients were included, 24 with parasites in the parenchyma (PAR), 56 in the subarachnoid (SA) space and 19 in the ventricular system (IV). A questionnaire designed to assess exposure to classic NC risk factors 5, 10, 15, 20 and more than 20 years prior to diagnosis was applied. The results were compared between the three groups. Also, asymptomatic relatives of patients who had shared their living conditions in childhood or more recently were included and underwent brain scan and blood testing for specific antibodies.

RESULTS

Over the course of their lives, exposure to risk factors decreased significantly for all patients, although the decrease was more evident in patients with parasites in the SA space (p < 0.001) compared to patients with PAR (p = 0.011) or IV cysts (p = 0.020). Five years prior to diagnosis, exposure to risk factors was significantly higher in patients with PAR or IV NC than in patients with SA NC (p = 0.04). Furthermore, individuals in close contact with PAR or IV patients in the years preceding diagnosis were more likely to have asymptomatic NC, specific antibodies in sera, particularly IgM, compared to individuals in close contact with SA patients during the same period.

CONCLUSIONS

All these findings are highly suggestive of the possibility of a more recent infection of patients affected by parenchymal and ventricular NC than of patients with subarachnoid NC. Consequently, subarachnoid disease could be considered a chronic disease, which, probably contributes to the severity of the disease as well as the minimal response to medical treatment.

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.

Public health trends in neurologically relevant infections: a global perspective

Neuroinfectious diseases represent a growing threat to public health globally. Infections of the central nervous system remain challenging to diagnose and treat, partially driven by the fact that a high proportion of emerging pathogens are capable of causing neurological disease. Many of the trends driving the emergence of novel pathogens, including climate change, ecological degradation, urbanization, and global travel, have accelerated in recent years. These circumstances raise concern for the potential emergence of additional pathogens of pandemic potential in the coming years, necessitating a stronger understanding of the forces that give rise to the emergence and spread of neuroinvasive pathogens and a commitment to public health infrastructure to identify and treat these diseases. In this review, we discuss the clinical and epidemiological features of three types of emerging neuroinvasive pathogens of significant public health consequences that are emblematic of key ongoing trends in global health. We first discuss dengue viruses in the context of climate change, considering the environmental factors that allow for the expansion of the geographic range and seasonal population of the viruses' vector. We then review the rising prevalence of fungal meningitis secondary to medical tourism, a trend representative of the highly globalized nature of modern healthcare. Lastly, we discuss the increasing prevalence of antibiotic-resistant neurological infections driven by the intersection of antibiotic overuse in medical and agricultural settings. Taken together, the rising prevalence of these conditions necessitates a recommitment to investment in public health infrastructure focused on local and global infectious disease surveillance coupled with ongoing development of novel therapeutics and vaccines for emerging pathogens. Such emerging threats also obviate the need to address the root causes driving the emergence of novel infectious diseases, including a sustained effort to address anthropogenic climate change and environmental degradation.

[Neuroradiological and pathohistological markers of the main epileptogenic substrates in children. Other cerebral disorders]

High-resolution MRI is an important tool in the diagnosis of structural epilepsy |in determining the seizure initiation zones, identification of the mechanisms of epileptogenesis in predicting outcomes and preventing postoperative complications in patients. In this article we have tried to demonstrate the neuroradiological and pathohistological characteristics of the main epileptogenic substrates in children using modern classification. The second part of the article is devoted to the spectrum of epileptogenic cerebral disorders, in addition to cortical malformations.

Calcified Neurocysticercosis: Demographic, Clinical, and Radiological Characteristics of a Large Hospital-Based Patient Cohort

Neurocysticercosis (NCC), the infection of the central nervous system caused by Taenia solium larvae (cysticerci), is a major cause of acquired epilepsy worldwide. Calcification in NCC is the most common neuroimaging finding among individuals with epilepsy in T. solium-endemic areas. We describe the demographic, clinical, and radiological profiles of a large hospital cohort of patients with calcified NCC in Peru (during the period 2012-2022) and compared profiles between patients with and without a previous known diagnosis of viable infection. A total of 524 patients were enrolled (mean age at enrollment: 40.2 ± 15.2 years, mean age at symptom onset: 29.1 ± 16.1 years, 56.3% women). Of those, 415 patients (79.2%) had previous seizures (median time with seizures: 5 years, interquartile range (IQR): 2-13 years; median number of seizures: 7 (IQR: 3-32)), of which 333 (80.2%) had predominantly focal to bilateral tonic-clonic seizures; and 358 (68.3%) used antiseizure medication). Patients had a median number of three calcifications (IQR: 1-7), mostly located in the frontal lobes (79%). In 282 patients (53.8%) there was a previous diagnosis of viable infection, while 242 only had evidence of calcified NCC since their initial neuroimaging. Most patients previously diagnosed with viable infection were male, had previous seizures, had seizures for a longer time, had more calcifications, and had a history of taeniasis more frequently than patients without previously diagnosed viable infection (all p < 0.05). Patients with calcified NCC were heterogeneous regarding burden of infection and clinical manifestations, and individuals who were diagnosed after parasites calcified presented with milder disease manifestations.

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.

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.

Evaluating the Role of Corrals and Insects in the Transmission of Porcine Cysticercosis: A Cohort Study

The widespread dispersion of pigs infected with cysticercosis across endemic villages, low cyst burden among infected pigs, and low prevalence of taeniasis all suggest that pig ingestion of human feces is not the only mode of transmission for Taenia solium. Our objective was to evaluate the risk of porcine cysticercosis associated with exposure to human feces, dung beetles, and flies in an endemic community setting. We used a cluster-randomized cohort design to compare the risk of developing antibodies and infection among 120 piglets raised in either free-roaming (FR), standard corral (SC), or netted corral environments (NC). We collected monthly blood samples to detect serum antibodies and necropsied all pigs after 10 months to identify cysts. A total of 66 piglets developed antibodies with the relative risk of seropositivity in FR vs. all corralled pigs increasing significantly after 18 weeks. Of 108 necropsied pigs, 15 had T. solium cysts, all belonging to the FR group. Corrals were protective against infection but less so against seropositivity. NC, which did not completely exclude insects, did not provide added protection against seropositivity as compared to SC. The results of this study suggest that dung beetles and flies do not play an important role in infection.

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.

Neurocysticercosis: challenges in pediatric neurosurgery practice

PURPOSE

Neurocysticercosis (NCC) is considered a neglected infectious disease, but the most common parasitic disease of the central nervous system (CNS). Due to oral tendencies in childhood, it is hypothesized that individuals are infected around this age and develop symptoms as lately as during young adulthood. Although it is considered a benign disease, it may cause great impact in the patient's quality of life due to epilepsy, visual symptoms, and hydrocephalus, which eventually requires frequent hospitalizations. The treatment of hydrocephalus is the main challenge for neurosurgeons.

METHODS

We performed a concise review on neurocysticercosis in children and the main presentations of NCC in the neurosurgery practice and a systematic review on hydrocephalus secondary to extraparenchymal NCC.

RESULTS

Our review showed a rate of complete resolution of hydrocephalus secondary to NCC of around 80% with the first attempt of surgical treatment combined with medication therapy. Endoscopic removal of the intraventricular cysts with third ventriculostomy was the most common treatment modality. Patients previously managed with ventricular shunts are likely to have worse outcomes and complications.

CONCLUSION

Endoscopic approach is the gold standard surgical treatment for hydrocephalus secondary to neurocysticercosis.

Diagnosing neurocysticercosis in skeletonized human remains of forensic importance

Neurocysticercosis is endemic in many parts of the underdeveloped and developing countries, with continuous presence in developed countries due to the influx of migrants from regions where the diseases are endemic. Neuroimaging, anatomic pathological techniques, immunodiagnostic tests, clinical examination and epidemiologic considerations will easily provide the diagnosis. However, physicians in developed countries are perhaps progressively missing the diagnosis, and need to re-acquaint themselves with the condition and acquire a high suspicion index. The authors present a medicolegal case where the forensic team made a conclusion of neurocysticercosis (among other diagnoses), following post mortem examination of a largely skeletonized and mummified human remains. Characteristic changes were observed in the calvarium of the decedent at autopsy. Review of the antemortem medical records revealed that Computed Tomography (CT) scan had 12 years earlier, suggested diagnostic features in a Hispanic migrant, but the attending surgeons failed to consider the possibility of the condition. Physicians should pay attention to suggestive clinical findings especially when attending to individuals coming from endemic parts of the world. Cysticercosis remains endemic and a misdiagnosis can potentially attract medical malpractice suits. Forensic pathologists should also consider the possibility of uncommon clinical disorders, even in skeletonized remains. Perhaps an earlier diagnosis might have altered the outcome in the decedent.

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.

Case report and review of literature: Isolated intramedullary spinal neurocysticercosis

Background

Cases of isolated intramedullary spinal neurocysticercosis are extremely rare. Only 25 cases have been reported before 2022. Due to its rarity, the diagnosis of spinal neurocysticercosis may be missed.

Case presentation

We describe a 37-year-old female patient who developed back pain and lower extremity weakness and was found to have an intramedullary thoracic spine cystic lesion. She was taken to the operating room for resection of the lesion. Pathology revealed a larval cyst wall consistent with neurocysticercosis. The patient was started on albendazole and dexamethasone. Her exam improved post-operatively, and she was able to ambulate with minimal difficulty at the time of follow up.

Conclusion

The case provides insights on the diagnosis and treatment of isolated intramedullary spinal neurocysticercosis. Review of the literature suggests that combined surgical and medical intervention results in significant improvement in the patient's neurological exam, and decreases morbidity associated with the disease. We propose a treatment paradigm for this rare manifestation of neurocysticercosis.

Isolated Spinal Cord Neurocysticercosis

The incidence of neurocysticercosis is increasing in the US. The diagnosis is primarily made based on imaging findings, with clinical presentation and epidemiological exposure also playing a role. The differential diagnosis for neurocysticercosis (NCC) is extensive, and being able to differentiate between these conditions on imaging is crucial to making a proper diagnosis. Herein we present a case of a 37-year-old female who presented with lower extremity weakness and was found to have isolated spinal NCC. In this article, we will discuss the symptoms and imaging findings of neurocysticercosis to help guide diagnosis and management.

Paediatric neurocysticercosis in high income countries

BACKGROUND

Neurocysticercosis (NCC) is an unusual cause of seizures in high income settings. It typically presents as an afebrile seizure in a previously well child and can occur years after migration or travel.

METHODS

Children diagnosed with neurocysticercosis from 01 July 2005 to 30 June 2020 were identified from the electronic medical records of a tertiary children's hospital in Australia. Additionally, a 10-year compilation of case reports of paediatric NCC in high income settings was performed by medline search (publication years 2011-2021). Diagnosis and treatment of neurocysticercosis were reviewed with reference to diagnostic criteria of Del Brutto et al., and the 2017 Infectious Diseases Society of America treatment guidelines.

RESULTS

Over a fifteen-year period, eight children were diagnosed with NCC at our hospital in Sydney, Australia. Seizures and history of travel to or migration from South Asia were the two most frequently occurring findings. Children diagnosed after 2016 all received antiparasitic therapy. Outcomes were generally favorable, though long-term epilepsy resulted in some cases. Compiled case reports from high income settings revealed migration and travel exposures commensurate with local demographic patterns, and treatment approaches conforming with 2017 Infectious Diseases Society of America guidelines.

CONCLUSIONS

Clinicians should be aware of NCC as a differential diagnosis in children from endemic areas presenting with unprovoked seizures as misdiagnosis can occur. Expert review of neuroimaging facilitates diagnosis and can avert unnecessary neurosurgery. In Australia, India was a key exposure country for NCC, reflecting its endemic burden of disease and local travel and migration patterns.

Neurocysticercosis control for primary epilepsy prevention: a systematic review

Neurocysticercosis (NCC) is a leading cause of preventable epilepsy in lower- and upper- middle-income countries (LMICs/UMICs). NCC is a human-to-human transmitted disease caused by ingestion of Taenia solium eggs from a Taenia carrier. T. solium infection control is the key to reduce NCC incidence. This systematic review aims to identify T. solium control programs that can provide frameworks for endemic areas to prevent NCC-related epilepsy. A systematic search was conducted in PubMed/Medline, Embase, Web of Science, and Cochrane Library databases in March 2021. After title and abstract review, full texts were screened for qualitative analysis. Additional articles were identified via citation search. Of 1322 total results, 34 unique studies were included. Six major intervention types were identified: national policy (8.8%), community sanitation improvement (8.8%), health education (8.8%), mass drug administration (29.4%), pig vaccination and treatment (32.4%), and combined human and pig treatment (11.8%). Overall, 28 (82.4%) studies reported decreased cysticercosis prevalence following the intervention. Only health education and combined human and pig treatment were effective in all selected studies. NCC causes preventable epilepsy in LMICs/UMICs and its incidence can be reduced through T. solium control. Most interventions that disrupt the T. solium transmission cycle are effective. Long-term sustained results require comprehensive programs, ongoing surveillance, and collaborative effort among multisectoral agencies.

Reviewing a Decade of Outpatient Tropical Medicine in Houston, Texas

Tropical diseases cause significant morbidity among the world's poorest populations. Although more common in low- and middle-income countries, tropical diseases are also found among underserved populations living in high-income countries such as the United States. The National School of Tropical Medicine at Baylor College of Medicine and the Harris Health System founded a tropical medicine clinic-the Harris Health Tropical Medicine Clinic (HHTMC)-in Houston in 2011 in response to tropical disease-related morbidity in Texas. We conducted a retrospective chart review of a sample of patients older than 18 years of age who were referred to the HHTMC between October 2011 and January 2020. Of the 523 patients reviewed, 185 (35.4%) had mycobacterial infections, 184 (35.2%) had parasitic infections, 38 (7.3%) had fungal infections, 16 (3.1%) had eosinophilia without a confirmed clinical diagnosis, 28 (5.4%) had bacterial infections, and 13 (2.5%) had viral infections. The most common infections overall were extrapulmonary and latent tuberculosis (n = 169), neurocysticercosis (n = 78), strongyloidiasis (n = 28), Chagas disease (n = 25), and schistosomiasis (n = 12). The epidemiology of tropical diseases in the United States is understudied at national and regional levels. This 10-year retrospective study contributes to bridging this knowledge gap by detailing the frequencies of tropical disease diagnoses made at the HHTMC in Houston, TX. These data highlight areas for advancement in the field of tropical medicine within the United States, such as improving front-line health-care provider education; establishing tropical medicine clinics in areas of high prevalence such as the Gulf Coast, Appalachia, and urban areas; and developing comprehensive, systematic national tropical disease screening programs and patient registries.

Seizures Related to Neurocysticercosis and Cocaine Use

Neurocysticercosis (NCC) is an infection of the central nervous system with Taenia solium cysts that most commonly results in seizures. In stable patients without recent symptoms, these seizures may be provoked by seizure threshold-lowering drugs such as cocaine. This case details a 38-year-old male with a past medical history of epilepsy presenting with seizures due to comorbid NCC and cocaine use. This case was complicated by the lack of available information regarding the patient’s past medical history and medication use. We highlight the importance of obtaining a full work-up, including brain imaging, to provide optimal treatment for patients with seizures despite a history of drug use.

Chagas Disease Prevalence in a Cohort of Neurocysticercosis Patients in a Nonendemic Setting

In a cohort of mostly Central American immigrants with confirmed neurocysticercosis (NCC), 3.1% were confirmed positive for Chagas disease (CD). The majority were diagnosed with NCC before age 50. Entry to care for NCC is an opportunity for early detection and possible treatment for CD in those from endemic areas.

Neurocysticercosis in Children

Neurocysticercosis is one of the most common parasitic infections in the central nervous system in children. The usual clinical manifestation is new-onset focal seizure. However, there are other multiple clinical manifestations, such as increased intracranial pressure, meningoencephalitis, spinal cord syndrome, and blindness. The diagnosis needs high index of suspicion with clinical history, physical examination, neuroimaging, and immunologic studies. Recent advances in neuroimaging and serology facilitate the accurate diagnosis. Management of neurocysticercosis should focus on critical symptoms first, such as the use of antiepileptic drugs and medical or surgical therapy for increased intracranial pressure.

Evaluating the Association of Calcified Neurocysticercosis and Mesial Temporal Lobe Epilepsy With Hippocampal Sclerosis in a Large Cohort of Patients With Epilepsy

BACKGROUND

Neurocysticercosis (NCC) is a parasitic infection of the central nervous system that has been associated with mesial temporal lobe epilepsy with hippocampal sclerosis (MTLE-HS). However, this association has not been completely established.

OBJECTIVE

To evaluate the prevalence of calcified NCC (cNCC), its characteristics and a possible association between cNCC and MTLE-HS in a cohort of 731 patients with epilepsy.

METHODS

We review clinical, EEG and neuroimaging findings of 731 patients with epilepsy. From these, 659 had CT-scans and 441 patients had complete neuroimaging with CT-scans and MRI. In these patients, we review the prevalence and characteristic of epilepsy in cNCC and in MTLE-HS patients.

RESULTS

Forty-two (6.4%) of the 659 patients studied with CT-scans had cNCC. cNCC lesions were more frequent in women than in men (n = 33-78.6% vs. n = 09-21.4%, respectively; OR = 3.64;(95%CI = 1.71-7.69); p < 0.001). cNCC was more often in patients who developed epilepsy later in life, in older patients, in patients who had a longer history of epilepsy, and in those with a lower educational level. MTLE-HS was observed in 93 (21.1%) of 441 patients that had complete neuroimaging, and 25 (26.9%) of these 93 patients also had cNCC. Calcified NCC was observed in only 17 (4.9%) of the remaining 348 patients that had other types of epilepsy rather than MTLE-HS. Thus, in our cohort, cNCC was more frequently associated with MTLE-HS than with other forms of epilepsy, O.R. = 11.90;(95%CI = 6.10-23.26); p < 0.0001).

CONCLUSIONS

As expected, in some patients the epilepsy was directly related to cNCC lesional zone, although this was observed in a surprisingly lower number of patients. Also, cNCC lesions were observed in other forms of epilepsy, a finding that could occur only by chance, with epilepsy probably being not related to cNCC at all. In this cohort, cNCC was very commonly associated with MTLE-HS, an observation in agreement with the hypothesis that NCC can contribute to or directly cause MTLE-HS in many patients. Given the broad world prevalence of NCC and the relatively few studies in this field, our findings add more data suggesting a possible and intriguing frequent interplay between NCC and MTLE-HS, two of the most common causes of focal epilepsy worldwide.

Identification and functional characterization of the siRNA pathway in Taenia crassiceps by silencing Enolase A

A gene silencing procedure on cysticerci of the taeniid cestode Taenia crassiceps is described. This is the first time this technique is reported in this species that is widely used as an animal model for human cysticercosis. Genome database searches were performed in order to find out if relevant genes involved in gene silencing and non-coding RNA processing, Argonaute and Dicer (AGO and Dcr) are present in T. crassiceps. We found three AGO and two Dcr orthologues that were designed TcAGO1, Tc2 and Tc3, as well as TcDcr1 and TcDcr2. In order to elucidate the evolutionary relationships of T. crassiceps TcAGO and TcDcr genes, separate phylogenetic analyses were carried out for each, including AGO and Dcr orthologues of other 20 platyhelminthes. Our findings showed a close phylogenetic relationship of TcAGO and TcDcr with those previously described for Echinococcus spp. Our RT-PCR studies demonstrated expression of all TcAGO and TcDcr orthologues. Our results show that the gene silencing machinery in T. crassiceps is functionally active by inducing silencing of TcEnoA (∼90%). These results clearly show that gene silencing using siRNAs can be used as a molecular methodology to study gene function in taeniid cestodes.

The Role of Serial Imaging in Neurocysticercosis for Disease Resolution

Neurocysticercosis (NCC), the most common parasitic infection of the CNS in humans, is a frequent cause of seizure disorders and epilepsy. The cystic larvae Taenia solium is endemic to developing countries where the population raises pigs as a reliable source of food, however, massive immigration has now forced the surge of the disease in developed areas making it a worldwide problem. Clinical presentation is affected by the size, number, and location of the lesions within the brain, with the most common manifestations being seizures, headaches, and increased intracranial pressure. The appearance of NCC on radiological imaging helps determine the stage of the disease, required for appropriate antiparasitic treatment. In this article, we detail the case of a patient who presented for recurrent seizures after reportedly undergoing treatment for NCC years prior.

Epidemiology of Taenia solium infection in the Russian Federation in the last 20 years: a systematic review

Taenia solium is a zoonotic parasite that causes taeniasis and cysticercosis in humans (as final hosts) and cysticercosis in pigs (as intermediate hosts). The Russian Federation (RF) is traditionally considered as endemic for this zoonosis. However, the epidemiological data on T. solium infection have not been reviewed for the past 20 years, in which time dynamic economical and societal changes have occurred in the RF. The aim of this systematic review was to analyse the status of T. solium infection in RF in the 2000-2019 period. A literature search was conducted, which collected published articles, grey literature and official data on the epidemiology of T. solium taeniasis and cysticercosis in the RF published from 2000. From a total of 2021 articles and 24 official reports originally returned by the search, data were extracted from 12 full text articles and 11 official reports. Taenia solium taeniasis was continuously reported in the RF between 2000 and 2019, with a tenfold decrease in the incidence, from 0.2 per 100,000 population in 2000 to 0.023/100,000 in 2019. Also, the number of administrative units where taeniasis was detected continuously decreased. Cysticercosis in pigs had a declining trend after 2006. In conclusion, although decreasing, T. solium infection is still endemic in several regions and suspected to be endemic in most of the RF.

Fourth Nerve Palsy Due to Neurocysticercosis

Neurocysticercosis is the most common disease of the nervous system caused by a parasite. Ophthalmological manifestations of cysticercosis typically are due to direct intraorbital or intraocular involvement, parenchymal brainstem involvement, or secondary to hydrocephalus or increased intracranial pressure. We describe a patient with a unilateral fourth nerve palsy, a rare presentation of neurocyticercosis.

A Rare Case Report of Ruptured Cyst Presenting With Acute Meningitis in an Untreated Neurocysticercosis

Neurocysticercosis (NCC) rarely presents as acute meningitis; however, when it does, it is not distinguishable clinically from other more common infectious etiologies. Here, we report a case of NCC presenting as acute meningitis, which also highlights the importance of brain MRI imaging rather than CT where possible, the need to include MRI of the spine in patients with the subarachnoid disease, and the limitations of NCC antigen detection assay in cerebrospinal fluid when used in ventriculoperitoneal shunt specimens. A prolonged course of albendazole, praziquantel, and corticosteroids led to the resolution of our patient's NCC.

The Burden of Neurocysticercosis at a Single New York Hospital

Neurocysticercosis (NCC), a disease caused by the larval pork tapeworm Taenia solium, has emerged as an important infection in the United States. In this study, we describe the spectrum of NCC infection in eastern Long Island, where there is a growing population of immigrants from endemic countries. A retrospective study was designed to identify patients diagnosed with NCC using ICD-9 and ICD-10 codes in the electronic medical records at Stony Brook University Hospital between 2005 and 2016. We identified 52 patients (56% male, median age: 35 years) diagnosed with NCC in the only tertiary medical center in Suffolk County. Twenty-five cases were reported in the last three years of the study. Forty-eight (94%) patients self-identified as Hispanic or Latino in the electronic medical record. Twenty-two (44%) and 28 (56%) patients had parenchymal and extraparenchymal lesions, respectively. Nineteen (41.3%) patients presented with seizures to the emergency department. Six patients (11.7%) had hydrocephalus, and five of them required frequent hospitalizations and neurosurgical interventions, including permanent ventriculoperitoneal shunts or temporary external ventricular drains. No deaths were reported. The minimum accumulated estimated cost of NCC hospitalizations during the study period for all patients was approximately 1.4 million United States dollars (USD). In conclusion, NCC predominantly affects young, Hispanic immigrants in Eastern Long Island, particularly in zip codes correlating to predominantly Hispanic communities. The number of cases diagnosed increased at an alarming rate during the study period. Our study suggests a growing need for screening high-risk patients and connecting patients to care in hopes of providing early intervention and treatment to avoid potentially detrimental neurological sequelae.

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.

Surgical case of subacute headache in a young Latin American woman

Neurocysticercosis (NCC) is the most common helmintic disease affecting the central nervous system and a major cause of adult-onset epilepsy in the developing world. ¹ We describe a case of intraventricular NCC associated with hydrocephalus in a 28-year-old woman, Peruvian native, admitted to the emergency department for subacute headache and nausea. The cranial CT scan done showed asymmetric enlargement of the lateral ventricles which on cranial MRI was revealed to be due to an intraventricular cyst. An intraventricular endoscope was used to remove the cyst at the foramina of Monro, and therefore treat the obstructive hydrocephalus. NCC-a known cause of hydrocephalus in many Latin American countries-should be among the differential diagnosis in a patient with history of travel or residency in these countries. Treatment of choice for obstructive hydrocephalus caused by NCC is cyst removal with neuroendoscopy.

Pharmacokinetics, Safety, and Tolerability of Oxfendazole in Healthy Volunteers: a Randomized, Placebo-Controlled First-in-Human Single-Dose Escalation Study

Cysticercosis is a parasitic disease that frequently involves the human central nervous system (CNS), and current treatment options are limited. Oxfendazole, a veterinary medicine belonging to the benzimidazole family of anthelmintic drugs, has demonstrated substantial activity against the tissue stages of Taenia solium and has potential to be developed as an effective therapy for neurocysticercosis. To accelerate the transition of oxfendazole from veterinary to human use, the pharmacokinetics, safety, and tolerability of oxfendazole were evaluated in healthy volunteers in this phase 1 first-in-human (FIH) study. Seventy subjects were randomly assigned to receive a single oral dose of oxfendazole (0.5, 1, 3, 7.5, 15, 30, or 60 mg oxfendazole/kg body weight) or placebo and were followed for 14 days. Blood and urine samples were collected, and the concentrations of oxfendazole were measured using a validated ultraperformance liquid chromatography mass spectrometry method. The pharmacokinetic parameters of oxfendazole were estimated using noncompartmental analysis. Oxfendazole was rapidly absorbed with a mean plasma half-life ranging from 8.5 to 11 h. The renal excretion of oxfendazole was minimal. Oxfendazole exhibited significant nonlinear pharmacokinetics with less than dose-proportional increases in exposure after single oral doses of 0.5 mg/kg to 60 mg/kg. This nonlinearity of oxfendazole is likely due to the dose-dependent decrease in bioavailability that is caused by its low solubility. Oxfendazole was found to be well tolerated in this study at different escalating doses without any serious adverse events (AEs) or deaths. There were no significant differences in the distributions of hematology, biochemistry, or urine parameters between oxfendazole and placebo recipients. (This study has been registered at ClinicalTrials.gov under identifier NCT02234570.).

Pediatric Neurocysticercosis

Neurocysticercosis is the most common helminth infection of nervous system in humans caused by the encysted larvae of Taenia solium. It is a major cause of epilepsy in tropical areas and the most common cause of focal-onset seizures in North Indian children. Children with neurocysticercosis have pleomorphic manifestations depending on the location, number and viability of the cysts and host response. In endemic areas, neurocysticercosis should be clinically suspected in any child with recent-onset seizures, headache or focal motor deficits where there is no other suggestion of an underlying neurological disorder. Diagnosis of neurocysticercosis is essentially based on neuroimaging; visualization of a scolex is diagnostic. Management includes use of cysticidal drugs usually albendazole, which seems to be effective for lesion resolution and seizure remission, use of steroids and anti-epileptic drugs. Single lesions portend good prognosis with resolution of lesions in >60% of the cases within 6 mo and good seizure control. Prognosis is guarded in cysticercus encephalitis, racemose and extraparenchymal neurocysticercosis.

Axonal swellings and spheroids: a new insight into the pathology of neurocysticercosis

Neurocysticercosis is a parasitic brain disease caused by the larval form (Cysticercus cellulosae) of Taenia solium and is the leading cause of preventable epilepsy worldwide. However, the pathophysiology and relation to the wide range of clinical features remains poorly understood. Axonal swelling is emerging as an important early pathological finding in multiple neurodegenerative diseases and as a cause of brain injury, but has not been well described in neurocysticercosis. Histological analysis was performed on human, rat and porcine NCC brain specimens to identify axonal pathology. Rat infection was successfully carried out via two routes of inoculation: direct intracranial injection and oral feeding. Extensive axonal swellings, in the form of spheroids, were observed in both humans and rats and to a lesser extent in pigs with NCC. Spheroids demonstrated increased immunoreactivity to amyloid precursor protein and neurofilament indicating probable impairment of axonal transport. These novel findings demonstrate that spheroids are present in NCC which is conserved across species. Not only is this an important contribution toward understanding the pathogenesis of NCC, but it also provides a model to analyze the association of spheroids with specific clinical features and to investigate the reversibility of spheroid formation with antihelminthic treatment.

Pediatric neurocysticercosis

BACKGROUND

Neurocysticercosis (NCC) is an infestation of the nervous system caused by encysted larvae of Taenia solium. NCC is an important acquired cause of epilepsy and other neurological manifestations especially in endemic areas. NCC in children has pleomorphic manifestations depending on the location, number, viability of the cysts, and host response. Even with advancing knowledge of the disease manifestations, many aspects related to diagnosis and treatment, particularly in children, still remain controversial and pose challenges to clinical practice. There is no gold standard test to diagnose NCC and the management recommendations are still emerging. This review provides an overview of diagnosis of NCC in children and its management with special focus on current challenges and future prospects.

DISCUSSION

In developing countries, NCC is important not only because of its frequency but also because of high morbidity and mortality rates associated, especially in cases in which it progresses to increased intracranial pressure. Because of its pleomorphic presentation, NCC should be considered in the differential diagnosis of a number of neurological conditions. Treatment with cysticidal therapy leads to reduction in seizure frequency and a faster resolution of lesions.

CONCLUSIONS

We have summarized the current approaches to diagnosis and treatment of NCC, recent advances in understanding the biology of NCC, and how one can take advantage of these new insights to formulate the next generation of clinical trials.

The rise of neglected tropical diseases in the "new Texas"

Within the last five years, the State of Texas has experienced either transmission or outbreaks of Ebola, chikungunya, West Nile, and Zika virus infections. Autochthonous transmission of neglected parasitic and bacterial diseases has also become increasingly reported. The rise of such emerging and neglected tropical diseases (NTDs) has not occurred by accident but instead reflects rapidly evolving changes and shifts in a “new” Texas beset by modern and globalizing forces that include rapid expansions in population together with urbanization and human migrations, altered transportation patterns, climate change, steeply declining vaccination rates, and a new paradigm of poverty known as “blue marble health.” Summarized here are the major NTDs now affecting Texas. In addition to the vector-borne viral diseases highlighted above, there also is a high level of parasitic infections, including Chagas disease, trichomoniasis, and possibly leishmaniasis and toxocariasis, as well as typhus-group rickettsiosis, a vector-borne bacterial infection. I also highlight some of the key shifts in emerging and neglected disease patterns, partly due to an altered and evolving economic and ecological landscape in the new Texas, and provide some preliminary disease burden estimates for the major prevalent and incident NTDs.