The Burden of Neurocysticercosis at a Single New York Hospital

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.

Taenia solium taeniasis/cysticercosis in Guatemala: a prevalent public health problem?

In Guatemala, neurocysticercosis (NCC) was first recognized in 1940; since then, cases of NCC have been reported in all Guatemalan departments. However, epidemiological studies on Taenia solium infections are scarce and most information remains unpublished. This study aims to provide evidence of T. solium infections as a public health problem in Guatemala. All information available, either published or unpublished, on T. solium infections in the country was compiled. Official data from the Ministry of Health for the period 2003-2019 were reviewed and analyzed, and all cases of T. solium infections were classified and counted. In total, 5246 cases of taeniasis and 454 cases of human cysticercosis were recorded. On the other hand, 44 studies were identified, mostly from local journals, which included 1951 cases of taeniasis, 2873 cases of human cysticercosis of which 543 were classified with complete diagnosis, and 2590 cases of porcine cysticercosis. Cases were classified by geographic region, patient sex, and Taenia species in taeniasis cases when information was available, and the departments with the highest number of taeniasis and cysticercosis cases were identified. Meanwhile, in Zacapa, a northeastern department of Guatemala with one the highest number of taeniasis cases, a young man diagnosed with a severe form of NCC and two cases of porcine cysticercosis (both confirmed by necropsy) were identified. Taken together, the data herein reported indicate that T. solium infections are a major health problem in Guatemala that needs to be addressed.

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.

CystiHuman: A model of human neurocysticercosis

INTRODUCTION

The Taenia solium tapeworm is responsible for cysticercosis, a neglected tropical disease presenting as larvae in the body of a host following taenia egg ingestion. Neurocysticercosis (NCC), the name of the disease when it affects the human central nervous system, is a major cause of epilepsy in developing countries, and can also cause intracranial hypertension, hydrocephalus and death. Simulation models can help identify the most cost-effective interventions before their implementation. Modelling NCC should enable the comparison of a broad range of interventions, from treatment of human taeniasis (presence of an adult taenia worm in the human intestine) to NCC mitigation. It also allows a focus on the actual impact of the disease, rather than using proxies as is the case for other models.

METHODS

This agent-based model is the first model that simulates human NCC and associated pathologies. It uses the output of another model, CystiAgent, which simulates the evolution of pig cysticercosis and human taeniasis, adding human and cyst agents, including a model of cyst location and stage, human symptoms, and treatment. CystiHuman also accounts for delays in the appearance of NCC-related symptoms. It comprises three modules detailing cyst development, seizure probability and timing, and intracranial hypertension/hydrocephalus, respectively. It has been implemented in Java MASON and calibrated in three endemic villages in Peru, then applied to another village (Rica Playa) to compare simulation results with field data in that village.

RESULTS AND DISCUSSION

Despite limitations in available field data, parameter values found through calibration are plausible and simulated outcomes in Rica Playa are close to actual values for NCC prevalence and the way it increases with age and cases with single lesions. Initial simulations further suggest that short-term interventions followed by a rapid increase in taeniasis prevalence back to original levels may have limited impacts on NCC prevalence.

Intramedullary parasite eggs, latent for three decades, mimicking acute transverse myelitis

Background

Intramedullary parasitic infection is extremely uncommon, and clinical presentation of Brown-Sequard syndrome is even rarer.

Case presentation

The authors report a case involving a 57-year-old woman with Brown-Sequard syndrome, in whom magnetic resonance imaging and clinical and epidemiological features were similar to those of acute transverse myelitis. Myelotomy suggested inflammation caused by latent parasite eggs in the spinal cord. Antiparasitic and steroid therapies were administered postoperatively. To the author’s knowledge, this is the first report to describe a surgical experience for Taenia solium eggs in the spinal cord.

Conclusion

Intramedullary parasitic infection is a diagnostic challenge that requires careful discrimination from other diseases. If parasite infection is suspected in a progressively deteriorating patient, myelotomy should be considered for rapid and accurate treatment.

Neurocysticercosis. A frequent cause of seizures, epilepsy, and other neurological morbidity in most of the world

Neurocysticercosis is endemic in most of the world and in endemic areas it accounts for approximately 30% of cases of epilepsy. Appropriate diagnosis and management of neurocysticercosis requires understanding the diverse presentations of the disease since these will vary in regards to clinical manifestation, sensitivity of diagnostic tests, and most importantly, therapeutic approach. This review attempts to familiarize tropical neurology practitioners with the diverse types of neurocysticercosis and the more appropriate management approaches for each.

A Large Case Series of Neurocysticercosis in Kuwait, a Nonendemic Arabian Gulf Country in the Middle East Region

Neurocysticercosis (NCC), a leading global cause of severe progressive headache and epilepsy, in developed or affluent countries is mostly diagnosed among immigrants from poor or developing Taenia solium taeniasis-endemic countries. Taeniasis carriers in Kuwait are routinely screened by insensitive stool microscopy. In this study, enzyme-linked immunoelectrotransfer blot (EITB) was used as a confirmatory test for NCC. Screening was performed on 970 patients referred for suspected NCC on the basis of relevant history and/or ring-enhancing lesions on computed tomography and/or magnetic resonance imaging during a 14-year period in Kuwait. Demographic data and clinical details were retrieved from laboratory or hospital records. EITB was positive in 150 subjects (15.5%), including 98 expatriates mostly originating from taeniasis-endemic countries and, surprisingly, 52 Kuwaiti nationals. The clinical details of 48 of 50 NCC cases diagnosed during 2014–2019 were available. Most common symptoms included seizures, persistent headache with/without fever, and fits or loss of consciousness. Cysticercal lesions were located at various brain regions in 39 of 48 patients. Multiple members of 3 families with NCC were identified; infection was linked to domestic workers from taeniasis-endemic countries and confirmed in at least 1 family. Our data show that NCC is predominantly imported in Kuwait by expatriates originating from taeniasis-endemic countries who transmit the infection to Kuwaiti citizens.