Concordance between two monoclonal antibody-based antigen detection enzyme-linked immunosorbent assays for measuring cysticercal antigen levels in sera from pigs experimentally infected with Taenia solium and Taenia hydatigena.

BACKGROUND: Antigen detection in Taenia solium cysticercosis confirms viable infection in the intermediate host (either pig or human). The reference B158/B60 monoclonal antibody (mAb)-based Ag-enzyme-linked immunosorbent assay (ELISA) has acceptable levels of sensitivity and specificity in human neurocysticercosis with multiple brain cysts, although its sensitivity is lower in cases with single brain cysts, whereas in porcine cysticercosis the assay specificity is affected by its frequent cross-reaction with Taenia hydatigena, another common cestode found in pigs. Our group has produced 21 anti-T. solium mAbs reacting against antigens of the whole cyst, vesicular fluid, and secretory/excretory products, identifying TsW8/TsW5 as the most promising pair of mAbs for an Ag-ELISA. METHODS: We report the use of the TsW8/TsW5 Ag-ELISA to measure cysticercus antigen levels [expressed as optical density (OD) values] in two panels of sera collected from day 0 (baseline) to day 90 postinfection (PI) from pigs experimentally infected with T. solium (n = 26) and T. hydatigena (n = 12). At baseline and on days 28 and 90 PI, we used Bland-Altman (BA) analysis and Lin's concordance correlation coefficients (CCC) to determine the concordance between the TsW8/TsW5 and the B158/B60 Ag-ELISA. RESULTS: The TsW8/TsW5 Ag-ELISA was able to efficiently measure circulating antigen levels in T. solium-infected pigs, similar to that obtained with the B158/B60 Ag-ELISA. Almost all paired log-OD differences between assays were within the limits of agreement (LoA) in the BA analysis at baseline and on days 28 and 90 PI (92.3%, 100%, and 100%, respectively), and a high concordance of log-ODs between assays was also found (Lin's CCC: 0.69, 0.92, and 0.96, respectively, all P < 0.001). In pigs infected with T. hydatigena, almost all paired log-OD differences were within the LoA in the BA analysis, whereas the concordance of log-ODs between assays was low at baseline (Lin's CCC: 0.24) but increased on days 28 and 90 PI (Lins' CCC: 0.88 and 0.98, P < 0.001). CONCLUSIONS/SIGNIFICANCE: The TsW8/TsW5 Ag-ELISA recognizes antigens in pigs with T. solium cysticercosis and is highly concordant with the B158/B60 Ag-ELISA. However, its diagnostic use is hampered by cross-reactions with T. hydatigena, as in other mAb-based Ag-ELISAs.

Diagnóstico de neurocisticercosis en pacientes con epilepsia residentes en el suroeste de la República Dominicana / Diagnosis of neurocysticercosis in patients with epilepsy living in the south-western Dominican Republic

Introducción La neurocisticercosis (NCC), una posible causa de epilepsia con datos epidemiológicos limitados en la República Dominicana, es endémica en cuatro provincias de la región suroeste. El objetivo de este estudio fue determinar la asociación entre la NCC y la epilepsia en personas que viven en estas regiones endémicas, así como obtener datos preliminares sobre la prevalencia de NCC en estas provincias. Sujetos y métodos Se utilizó un diseño de casos y controles compuesto por 111 pacientes con epilepsia de causa desconocida y 60 controles sin epilepsia ni NCC. El diagnóstico de NCC se basó en la tomografía computarizada y la resonancia magnética del cráneo, así como en el inmunotransferencia de Western para anticuerpos séricos contra Taenia solium, siguiendo los criterios de Del Brutto et al. Resultados Se encontró NCC en el 27% de los pacientes con epilepsia (n = 30/111) y en el 5% de los controles (n = 3/60); los casos de epilepsia tenían siete veces más probabilidades de tener NCC que los controles (odds ratio = 7,04, intervalo de confianza al 95%: 2,04-24,18; p < 0,001). Las características sociodemográficas de los participantes, como la edad, el sexo, el nivel de escolaridad, la ocupación y la provincia de residencia no mostraron significación estadística en cuanto a la asociación con NCC. Conclusiones Este estudio sugiere que la NCC está fuertemente asociada con la epilepsia en la región suroeste de la República Dominicana, y destaca la necesidad de medidas de salud pública para mejorar la prevención, el diagnóstico y el tratamiento de ambas enfermedades. (AU)

INTRODUCTION Neurocysticercosis (NCC), a possible cause of epilepsy with limited epidemiological data in the Dominican Republic, is endemic in four provinces in the country’s south-western region. This study aimed to determine the association between NCC and epilepsy among people living in these endemic regions, and to obtain preliminary data on the prevalence of NCC in these provinces. PATIENTS AND METHODS A case-control design was used, consisting of 111 patients with epilepsy with unknown causes, and 60 controls without epilepsy or NCC. The diagnosis of NCC was based on computed tomography and magnetic resonance imaging of the skull, as well as Western immunoblotting for serum antibodies using Taenia solium, following the criteria of Del Brutto et al. RESULTS NCC was found in 27% of the epileptic patients (n = 30/111) and in 5% of the controls (n = 3/60); the probability of the epileptic patients having NCC was seven times higher than the controls (odds ratio = 7.04, 95% confidence interval: 2.04-24.18; p < 0.001). The participants’ sociodemographic characteristics, including their age, sex, level of education, occupation, and province of residence presented no statistical significance in terms of their association with NCC. CONCLUSIONS This study suggests that NCC is strongly associated with epilepsy in the south-western region of the Dominican Republic, and highlights the need for public health measures to improve the prevention, diagnosis and treatment of both diseases. (AU)

Understanding the pathogenic mechanisms and therapeutic effects in neurocysticercosis.

Despite being a leading cause of acquired seizures in endemic regions, the pathological mechanisms of neurocysticercosis are still poorly understood. This study aims to investigate the impact of anthelmintic treatment on neuropathological features in a rat model of neurocysticercosis. Rats were intracranially infected with Taenia solium oncospheres and treated with albendazole + praziquantel (ABZ), oxfendazole + praziquantel (OXF), or untreated placebo (UT) for 7 days. Following the last dose of treatment, brain tissues were evaluated at 24 h and 2 months. We performed neuropathological assessment for cyst damage, perilesional brain inflammation, presence of axonal spheroids, and spongy changes. Both treatments showed comparable efficacy in cyst damage and inflammation. The presence of spongy change correlated with spheroids counts and were not affected by anthelmintic treatment. Compared to white matter, gray matter showed greater spongy change (91.7% vs. 21.4%, p < 0.0001), higher spheroids count (45.2 vs. 0.2, p = 0.0001), and increased inflammation (72.0% vs. 21.4%, p = 0.003). In this rat model, anthelmintic treatment destroyed brain parasitic cysts at the cost of local inflammation similar to what is described in human neurocysticercosis. Axonal spheroids and spongy changes as markers of damage were topographically correlated, and not affected by anthelmintic treatment.

Spatial transferability of an agent-based model to simulate Taenia solium control interventions.

BACKGROUND: Models can be used to study and predict the impact of interventions aimed at controlling the spread of infectious agents, such as Taenia solium, a zoonotic parasite whose larval stage causes epilepsy and economic loss in many rural areas of the developing nations. To enhance the credibility of model estimates, calibration against observed data is necessary. However, this process may lead to a paradoxical dependence of model parameters on location-specific data, thus limiting the model's geographic transferability. METHODS: In this study, we adopted a non-local model calibration approach to assess whether it can improve the spatial transferability of CystiAgent, our agent-based model of local-scale T. solium transmission. The calibration dataset for CystiAgent consisted of cross-sectional data on human taeniasis, pig cysticercosis and pig serology collected in eight villages in Northwest Peru. After calibration, the model was transferred to a second group of 21 destination villages in the same area without recalibrating its parameters. Model outputs were compared to pig serology data collected over a period of 2 years in the destination villages during a trial of T. solium control interventions, based on mass and spatially targeted human and pig treatments. RESULTS: Considering the uncertainties associated with empirical data, the model produced simulated pre-intervention pig seroprevalences that were successfully validated against data collected in 81% of destination villages. Furthermore, the model outputs were able to reproduce validated pig seroincidence values in 76% of destination villages when compared to the data obtained after the interventions. The results demonstrate that the CystiAgent model, when calibrated using a non-local approach, can be successfully transferred without requiring additional calibration. CONCLUSIONS: This feature allows the model to simulate both baseline pre-intervention transmission conditions and the outcomes of control interventions across villages that form geographically homogeneous regions, providing a basis for developing large-scale models representing T. solium transmission at a regional level.

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.

Imaging of congenital and developmental cystic lesions of the brain: a narrative review.

INTRODUCTION: Congenital and developmental intracranial cysts represent a large heterogenous group with varied presentations and etiologies. They can range from normal variants to pathologic lesions often associated with known congenital syndromes or acquired insults. While some are incidentally found, others are symptomatic or may become symptomatic over time. The preferred type of neuroimaging for timely diagnosis helps determine appropriate management and treatment, if indicated. AREAS COVERED: In this narrative review article, authors present a comprehensive description of developmental cystic lesions. Imaging descriptions are provided for each type of cystic lesion as well as several representative images. EXPERT OPINION: As advanced neuroimaging techniques become more ubiquitous in clinical use, more light may be shed on the natural history of certain intracranial cystic lesions throughout the lifespan. This includes prenatal imaging for early identification and prognostication to surveillance imaging into advanced age to ascertain associations of certain cystic lesions with age-related cognitive dysfunction.

Assembly and phylogeographical analysis of novel Taenia solium mitochondrial genomes suggest stratification within the African-American genotype.

BACKGROUND: Taenia solium is a parasite of public health concern, causing human taeniasis and cysticercosis. Two main genotypes have been identified: Asian and African-American. Although characterizing T. solium genotypes is crucial to understanding the genetic epidemiology of its diseases, not much is known about the differences between T. solium mitochondrial genomes from different genotypes. Also, little is known about whether genotypes are further subdivided. Therefore, this study aimed to identify a set of point mutations distributed throughout the T. solium mitochondrial genome that differentiate the African-American from the Asian genotype. Another objective was to identify whether T. solium main genotypes are further stratified. METHODS: One Mexican and two Peruvian T. solium mitochondrial genomes were assembled using reads available in the NCBI Sequence Read Archive and the reference genome from China as a template. Mutations with respect to the Chinese reference were identified by multiple genome alignment. Jensen-Shannon and Grantham scores were computed for mutations in protein-coding genes to evaluate whether they affected protein function. Phylogenies by Bayesian inference and haplotype networks were constructed using cytochrome c oxidase subunit 1 and cytochrome b from these genomes and other isolates to infer phylogeographical relationships. RESULTS: A set of 31 novel non-synonymous point mutations present in all genomes of the African-American genotype were identified. These mutations were distributed across the mitochondrial genome, differentiating the African-American from the Asian genotype. All occurred in non-conserved protein positions. Furthermore, the analysis suggested a stratification of the African-American genotypes into an East African and a West African sublineage. CONCLUSIONS: A novel set of 31 non-synonymous mutations differentiating the main T. solium genotypes was identified. None of these seem to be causing differences in mitochondrial protein function between parasites of the two genotypes. Furthermore, two sublineages within the African-American genotype are proposed for the first time. The presence of the East African sublineage in the Americas suggests an underestimated connection between East African and Latin American countries that might have arisen in the major slave trade between Portuguese Mozambique and the Americas. The results obtained here help to complete the molecular epidemiology of the parasite.

Development and Laboratory Evaluation of a Simple, Field-Applicable Coproantigen Enzyme-Linked Immunosorbent Assay for Diagnosis of Taeniasis in Northern Peru.

Coproantigen detection by enzyme-linked immunosorbent assay (coAg ELISA) is a vital tool for detecting and treating cases of Taenia solium taeniasis. However, the assay's procedures require costly materials and sophisticated equipment, which are typically inaccessible in rural settings where the disease is endemic. To overcome these barriers, we developed and evaluated a field-applicable coAg ELISA. The field coAg ELISA was developed and evaluated across four phases using known positive and negative stool samples collected from northern Peru. Phase I focused on field assay development, phase II on a small-scale performance evaluation, phase III on a large-scale evaluation, and phase IV on the use and reliability of a colorimetric scale card. All samples were processed using the field and standard assay procedures and compared using signal-to-noise ratios, correlation tests, performance characteristics, and agreement statistics where appropriate. The field coAg ELISA using reagents stored at -20°C and commercially available water and milk powder, and relying on spontaneous separation of the supernatant, had performance comparable to the standard assay. The field coAg ELISA was strongly correlated with the standard in both the small- and large-scale laboratory evaluation (r = 0.99 and r = 0.98, respectively). Finally, the field assay had an almost perfect agreement between independent readers (kappa = 0.975) and between each reader and the spectrophotometer. The field coAg ELISA demonstrated performance comparable to the standard, providing a low-cost alternative to the standard assay for identifying cases of intestinal taeniasis in a low-resource setting.

Older Age in Subarachnoid Neurocysticercosis Reflects a Long Prepatent Period.

Patients with subarachnoid neurocysticercosis (NCC) are usually older than those with parenchymal disease. Whether this difference reflects a prolonged presymptomatic period or a delay in diagnosis is not clear. From 408 eligible patients, we retrospectively compared the age at symptom onset in 140 patients diagnosed with parenchymal (pure viable or pure calcified) and subarachnoid NCC who had a confirmatory image available not more than 2 years after the beginning of symptoms. Patients with mixed (parenchymal and subarachnoid) NCC or those with parenchymal cysts at different stages (viable and/or degenerating and/or calcified) were not included. After controlling by sex and residence in rural endemic regions, the mean age at symptom onset in patients with subarachnoid disease was 13.69 years older than those with viable parenchymal disease. A long incubation period is a major contributing factor to older age at presentation in subarachnoid NCC, independent of delayed diagnosis or access to care.

Trigeminal neuralgia secondary to vascular compression and neurocysticercosis: illustrative case.

BACKGROUND: Trigeminal neuralgia (TN) is a frequent neurosurgical problem negatively influencing the quality of life of patients. The standard surgical treatment is microvascular decompression for primary cases and decompression of the mass effect, mainly tumors, for secondary cases. Neurocysticercosis (NCC) in the cerebellopontine angle is a rare etiology of TN. The authors report a case in which NCC cysts around the trigeminal nerve coexisted with a vascular loop, which compressed the exit of the trigeminal nerve from the pons. OBSERVATIONS: A 78-year-old woman presented with a 3-year history of persistent severe pain in the left side of her face, refractory to medical treatment. On gadolinium-enhanced magnetic resonance imaging, cystic lesions were observed around the left trigeminal nerve and a vascular loop was also present and in contact with the nerve. A retrosigmoid approach for cyst excision plus microvascular decompression of the trigeminal nerve was successfully performed. There were no complications. The patient was discharged without facial pain. LESSONS: Albeit rare, TN secondary to NCC cysts should be considered in the differential diagnosis in NCC-endemic regions. In this case, the cause of the neuralgia was probably both problems, because when both were treated, the patient improved.

Consistent Measurement of Parasite-Specific Antigen Levels in Sera of Patients with Neurocysticercosis Using Two Different Monoclonal Antibody (mAb)-Based Enzyme-Linked Immunosorbent Assays.

Monoclonal antibody (mAb)-based enzyme-linked immunosorbent assay (ELISA) is a complementary diagnosis technique for neurocysticercosis (NCC), which detects circulating parasite antigen (Ag) indicative of viable infection and Ag levels that correlate well with the parasite burden. In this study, we compared the performance of two Ag-ELISA techniques for the detection of NCC. We assessed the agreement between our in-house TsW8/TsW5 Ag-ELISA and the widely used B158/B60 Ag-ELISA for measuring T. solium antigen levels in the sera from 113 patients with calcified, parenchymal, and subarachnoid NCC. Concordance was demonstrated evaluating the limits of agreement (LoAs) stratified by the type of NCC. Both ELISA's detected 47/48 (97.8%) subarachnoid NCC cases. In parenchymal and calcified NCC, the B158/B60 Ag-ELISA detected 19/24 (79.2%) and 18/41 (43.9%) cases, while the TsW8/TsW5 Ag-ELISA detected 21/24 (87.5%) and 13/41 (31.7%), respectively. Parenchymal and calcified NCC obtained a perfect agreement (100%), indicating that all sample results were within the predicted LoA, while for subarachnoid NCC, the agreement was 89.6%. The high concordance between the assays was confirmed by Lin's concordance coefficient (LCC = 0.97). Patients with viable parenchymal NCC (LCC = 0.95) obtained the highest concordance between assays, followed by subarachnoid NCC (LCC = 0.93) and calcified NCC (LCC = 0.92). The TsW8/TsW5 Ag-ELISA and B158/B60 Ag-ELISA showed high Ag measurement correlations across diverse types of 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.

Imaging of infectious and inflammatory cystic lesions of the brain, a narrative review.

INTRODUCTION: Intracranial cysts and cyst-like intracranial lesions are common findings on neuroimaging with a wide range of etiologies. Oftentimes, cystic intracranial lesions are benign but in some parts of the world, infectious etiologies for cystic lesions in the brain are quite common. Prompt identification of the cause of a cystic brain lesion is paramount in determining appropriate treatment if indicated. AREAS COVERED: In this narrative review article, the authors present a comprehensive description of cystic lesions of infectious or inflammatory etiology. Imaging descriptions are provided for each type of cystic lesion as well as several representative images. EXPERT OPINION: The majority of diagnoses may be identified by CT and MR imaging. Yet some pathologies are still unable to be determined through standard imaging techniques and biopsy remains necessary for definitive diagnosis in some cases. Advanced neuroimaging such as metabolic/nuclear imaging and advanced MR hold promise with improved diagnostics but are not often available in geographic regions where these illnesses are endemic.

A Rapid Point-of-Care Assay for Cysticercosis Antigen Detection in Urine Samples.

We report a proof-of-concept study using a dipstick assay to detect Taenia solium antigen in urine samples of 30 patients with subarachnoid neurocysticercosis and 10 healthy control subjects. Strips were read in blind by two readers. The assay detected antigen in 29 of 30 cases and was negative in all 10 control samples. Although this study was performed in samples from individuals with subarachnoid neurocysticercosis who likely had high circulating antigen levels, it provides the proof of concept for a functional urine antigen point-of-care assay that detects viable cysts. Such an assay could serve to support a clinical diagnosis of suspect neurocysticercosis or to identify patients at risk of developing severe disease in areas where medical resources are limited, providing evidence to refer these individuals for imaging and specialized care as needed.

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.

Antibody Banding Patterns on the Enzyme-Linked Immunoelectrotransfer Blot (EITB) Assay Clearly Discriminate Viable Cysticercosis in Naturally Infected Pigs.

Enzyme-linked immunoelectrotransfer blot (EITB) detects antibodies against seven Taenia solium larvae antigens in three protein families (GP50, T24/42, and 8-kDa) with different structures and functions. EITB banding patterns against these antigens in pigs provide information about the course of infection and may discriminate viable cysticercosis. We analyzed the banding patterns and infection outcomes (presence of viable cysts, degenerated cysts, and any cysts) of 512 rural pigs. Banding patterns were grouped into homogenous classes using latent class analysis, and relationships with infection outcomes were assessed. Four classes were identified: 1 (n = 308, EITB-negative or positive for the GP50 family), 2 (n = 127, positive for GP50 (GP50 family), GP42-39 and GP24 (T24/42 family), but negative for 8-kDa antigens), 3 (n = 22, positive for GP50 and T24/42 antigens (GP42-39 and GP24), as well as to 8-kDa bands GP13, GP14, and GP18, but negative for GP21), and 4 (n = 55, positive for GP50 and T24/42 antigens, as well as to 8-kDa antigens GP21 and GP18 in combination). Pigs in classes 3 and 4 were more likely to have viable cysts (72.6% and 96.4%, respectively) than pigs in classes 1 and 2 (0.7% and 27.6%, respectively; p < 0.001). The number of infections with any cysts was higher in classes 3 and 4 (77.3% and 98.2%, respectively) and lower in classes 2 and 1 (34.7% and 4.9%, respectively; p < 0.001). Pigs with viable cysts represented >90% of pigs with any cysts in classes 3 and 4 (94.1% and 98.2%, respectively), while degenerated cysts were frequent among pigs with any cysts in classes 1, 3, and 2 (86.7%, 47.1%, and 43.2%, respectively; p < 0.001). EITB banding patterns strongly correlate with cysticercosis infection status in rural pigs, with classes 3 and 4 being more predictive of viable infections.

Experimental brain infection with cysticercosis in sheep. / Infección experimental cerebral con cisticercosis en ovejas.

OBJECTIVE.: To explore the feasibility of developing a sheep model of neurocysticercosis (NCC) by intracranial infection with T. solium oncospheres. MATERIALS AND METHODS.: We carried out an experimental infection model of NCC in sheep. Approximately 10 T. solium oncospheres previously cultured for 30 days were inoculated intracranially into ten sheep. The oncospheres, in 0.1 mL of physiological saline, were injected into the parietal lobe through an 18-gauge needle. RESULTS.: After three months, granulomas were found in two sheep. In a third sheep we identified a 5 mm diameter cyst in the right lateral ventricle and histological evaluation confirmed that the cyst corresponded to a T. solium larva. Immunohistochemistry with monoclonal antibodies directed against membrane components and excretory/secretory antigens of the T. solium cyst was also used to confirm the etiology of the found granulomas. One of them showed reactivity to the monoclonal antibodies used, thus confirming that it was a cysticercus. CONCLUSION.: This experiment is the proof of concept that it is possible to infect sheep with cysticercosis by intracranial inoculation.

OBJETIVO: . Explorar la viabilidad de desarrollar un modelo de neurocisticercosis (NCC) de oveja mediante infección intracraneal de oncosferas de T. solium. MATERIALES Y MÉTODOS.: Se realizó un modelo de infección experimental de NCC en ovejas. Se inocularon aproximadamente 10 posoncósferas de T. solium cultivadas previamente por 30 días por vía intracraneal en diez ovejas. Las oncósferas, en 0,1 mL de solución salina fisiológica, se inyectaron en el lóbulo parietal a través de una aguja de calibre 18. RESULTADOS.: Después de tres meses, en dos ovejas se encontraron granulomas y en una tercera identificó un quiste de 5 mm de diámetro en el ventrículo lateral derecho y la evaluación histológica confirmó que el quiste corresponde a una larva de T. solium. También se utilizó inmunohistoquímica con anticuerpos monoclonales dirigidos contra componentes de membrana y antígenos excretorios/secretorios del quiste de T. solium para confirmar la etiología de los granulomas encontrados. Uno de ellos mostro reactividad ante los anticuerpos monoclonales utilizados, confirmando así que se trató de un cisticerco. CONCLUSIÓN.: Este experimento es la prueba de concepto de que es posible infectar ovejas con cisticercosis por inoculación intracraneal.

Transventricular endoscopic approach to the anterior interhemispheric fissure for neurocysticercosis: illustrative cases.

BACKGROUND: Neurocysticercosis (NCC) is a global public health problem. It is a complex disease to manage and a cause of great morbidity and mortality in affected patients. Conventional surgical approaches have been used for many years, but currently, minimally invasive approaches are being used with good results. The authors present a case of NCC in the anterior interhemispheric fissure that was treated with a transventricular endoscopic approach. OBSERVATIONS: A 32-year-old male patient was admitted for persistent moderate headache and dizziness. Gadolinium-enhanced magnetic resonance imaging (MRI) showed multiple parenchymal, ventricular, and subarachnoid cystic lesions, especially in the anterior interhemispheric space. A transventricular endoscopic approach was selected and applied. There were no complications during surgery. Pathological analysis confirmed the diagnosis of NCC. Control MRI demonstrated the absence of cysts in the anterior interhemispheric space. LESSONS: Minimally invasive approaches are an excellent alternative for patients with NCC, especially if a patient requires more than one surgery.