Neurocysticercosis in Western Europe: a re-emerging disease?

Management of calcified cysticerci in the brain parenchyma: treating the dead parasite

INTRODUCTION

Calcifications are the end stage of many parenchymal brain cysticerci and may occur either spontaneously or as the result of treatment with cysticidal drugs. These lesions, traditionally considered inert and asymptomatic, have been associated with several complications that seem to be mostly related to brain damage and inflammation ensuing as the result of the exposure of the host's immune system to parasitic antigens trapped within calcifications.

AREAS COVERED

This review, based on the search of different electronic databases up to May 2024, focuses on the reported correlates and complications of calcified cysticerci (chronic headaches, seizures/epilepsy, hippocampal atrophy/sclerosis, gliomas), and the different interventions developed for their prevention and treatment. Common analgesics, non-steroidal anti-inflammatory drugs, corticosteroids, and antiseizure medications have been used with success but, with the exception of the latter, these drugs offer temporary relief of symptoms and support for their use is based on level 3 evidence.

EXPERT OPINION

Several strategies may reduce the severity of clinical consequences of calcified cysticerci. Probably, the most relevant intervention would be the prevention of their occurrence or reduction in their size. In this view, the use of bisphosphonates appears as a potential option that needs to be tested in humans.

A case-based review on the neuroendoscopic management of intraventricular and subarachnoid basal neurocysticercosis

OBJECTIVE

Extraparenchymal localization of neurocysticercosis (NCC) is rare in non-endemic areas. A case of mixed (intraventricular, IV, and subarachnoid basal, SAB) NCC was surgically treated using the neuroendoscope and a systematic review of the literature was performed with the aim to analyze the use of this instrument in the management of the extraparenchymal forms of the parasitic disease.

MATERIALS AND METHODS

Medline and Embase databases were searched for studies where the neuroendoscope was used for the management of IV/SAB NCC cysts, either for the cerebrospinal fluid diversion or cyst removal. Cyst location, complete removal, cyst breakage during removal, intraoperative and postoperative complications, administration of antihelmintic therapy, outcome and follow-up period were extracted from the articles.

RESULTS

281 patients were treated by means of the neuroendoscope. 254 patients who were described in retrospective cohort studies, came all from endemic areas, with no significant difference between sexes. Mean age at surgery was 30.7 years. Of all cysts reported in retrospective studies, 37.9% were located in the fourth ventricle. An attempt of cyst removal was described in the 84.6% of cases and an endoscopic third ventriculostomy was performed in another 76.4%. A small number of complications were reported intraoperatively (9.1%) obtaining, but a good recovery was achieved at follow-up. Only 17 ventriculoperitoneal shunts were placed after the first procedure, defining a low risk of postoperative hydrocephalus even in case of partial cyst removal.

CONCLUSION

Neuroendoscopic removal of an extraparenchymal NCC cyst is a safe procedure that should be preferred for lateral and third ventricle localization and, in a specialized centre, even for a localization in the fourth ventricle if feasible. It is also efficient because of the possibility of performing an internal CSF diversion concomitantly to cyst removal, avoiding the complication registered with VPS. The need for cysticidal treatment after surgery should be addressed in a prospective study.

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

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

Why are tapeworm carriers so difficult to find? A methodological proposal for their search and recovery

Neurocysticercosis, caused by the larval stage of Taenia solium, is a life-threatening condition and the most severe form of the disease. Yet, despite being a required link in the parasite life cycle, tapeworm carriers are rarely reported. This study is aimed to find and evaluate T. solium carriers, describing some characteristics of these patients and the treatment. Taeniasis cases were searched for in various Mexican states from 1983 to 2016. Previous informed consent, tapeworm-carrier patients were administered with niclosamide and a saline purge. Parasite specimens were recovered and identified, both morphologically and by PCR. From 117 treated patients, Taenia sp. specimens were obtained from 46 subjects (47.8%). From these, complete parasites were recovered from 42 (90.5%), and only detached proglottids from 4 patients. Cases were more frequent in Morelos, Chiapas, and Guerrero. More than one adult cestode was recovered from 4 patients (9.5%). To improve treatment efficacy and adherence, the drug was administered in late afternoon, resulting a high recovery yield of complete parasites (90.5%). The success rate of deworming campaigns in areas of Mexico and the world that are endemic for Taenia sp. could be improved by administering the treatment at times that do not interfere with the patients' daily activities, and national health authorities could apply this simple strategy to help eradication efforts in endemic areas. The detection of carriers will only be possible through the coordinated efforts of public and private health services, a better education of the general population to improve self-detection, and adequate, personalized diagnostic procedures for suspect cases.

Isolated neurocysticercosis of the spine presenting with low back pain and cauda equina syndrome: a case report

INTRODUCTION

Cysticercosis, caused by Cysticercus cellulosae, is one of the common parasitic diseases that can affect the central nervous system (neurocysticercosis, NCC). Isolated involvement of cysticercosis of the spine, without the involvement of the brain, has been very rarely reported.

CASE PRESENTATION

This report presented a case, who was presenting with low back pain with radiation and cauda equina syndrome (CES). On MRI, the patient was found to have a subarachnoid cystic lesion at the level of lumbosacral vertebrae. Under neurosurgery, the patient underwent L5/S1 laminectomy, decompression, and excision of the cyst. On histopathological examination, the patient was diagnosed of having Cysticercosis. Immediately after surgery, the patient had neurological deterioration. However, at the end of 1 year, the patient had significant improvement both neurologically and functionally.

DISCUSSION

Spinal NCC should be considered in the differential diagnosis for a patient, who presents with a cystic lesion in the spinal subarachnoid space. Surgical exploration and excision of the cysts should be conducted not only to establish the diagnosis but also to decompress the cord and peripheral nerves.

Optical Coherence Tomography Features of Ocular Cysticercosis: A Review of Literature With Observer Variation

Ocular cysticercosis is a sparsely reported condition, requiring urgent management. The gold standard for diagnosis is an in toto extraction of the cyst with subsequent histopathology. The procedure can be demanding in contrast to the frequently adopted practice of in vivo cyst lysis. The latter, however, obviates a conventional biopsy. We reviewed published optical coherence tomography (OCT) images of ocular cysticercosis for their suitability to surrogate a conventional biopsy and identified commonly reported features. We also used triple masking and ascertained the observer agreement on identification of these features. We found that the features of the parasite are much more clearly discernible as compared with features of the involved ocular tissue itself. The hyperreflective cyst wall and scolex and the hyporeflective cyst cavity had the highest frequency and observer agreement among all the analyzed features, suggesting their use for diagnosis. We could match many of the OCT features with the previously reported histopathological findings, supporting the role of OCT as a diagnostic adjunct and a substitute for conventional biopsy. Conversely, features of the ocular tissue could be judged poorly with low observer agreement, suggesting poor prognostic ability of OCT. [Ophthalmic Surg Lasers Imaging Retina 2022;53:446-454.].

The burden of T. solium cysticercosis and selected neuropsychiatric disorders in Mocuba district, Zambézia province, Mozambique

BACKGROUND

Taenia solium (neuro-)cysticercosis, a neglected tropical disease, can be associated with epileptic seizures and other neuropsychiatric (= neurological and psychiatric) disorders. This study aimed to evaluate the association of T. solium cysticercosis with selected neuropsychiatric disorders and/or symptoms (chronic headache, epileptic seizures/epilepsy and psychosis) in Mocuba district, Mozambique.

METHODOLOGY

Between March and May 2018, a cross-sectional study was conducted among 1,086 participants aged 2 years or above in Mocuba district, Zambézia province, central Mozambique, to assess the seroprevalence of human cysticercosis and risk factors for infection, as well as to explore its relation to selected neuropsychiatric disorders. Socio-demographic and clinical data were collected from each participant using a modified questionnaire designed by the Cysticercosis Working Group for Eastern and Southern Africa. Additionally, neuropsychiatric disorders, such as chronic headache, epileptic seizures/epilepsy and psychosis were assessed using four vignettes. T. solium antigen and cysticercosis IgG in serum were detected using both T. solium antigen B158/B60 enzyme linked immunosorbent assay (ELISA) and LDBIO Cysticercosis Western Blot, respectively.

PRINCIPAL FINDINGS

Overall, 112/1,086 participants (10.3%) were sero-positive for T. solium antigen or antibodies. Prevalence of antibodies (6.6%; n = 72) was higher than of antigens (4.9%; n = 54). In the questionnaires, 530 (49.5%) of participants reported chronic headache, 293 (27%) had generalized epileptic seizures, 188 (18%) focal seizures and 183 (18.3%) psychosis. We found a statistically significant association between seropositivity for T. solium and chronic headache (p = 0.013). Additionally, increasing age (p = 0.03) was associated with Ag-ELISA seropositivity.

CONCLUSIONS

Our study revealed that in Mocuba, T. solium cysticercosis is prevalent and associated with self-reported chronic headache. Additionally, in the study setting, the seroprevalence of cysticercosis increased with age. However, it is not associated with other neuropsychiatric disorders such epileptic seizures/epilepsy and psychosis. Future studies are needed to confirm the high burden of neuropsychiatric disorders and their possible etiology, including neurocysticercosis, using additional serological, molecular biological and radiological diagnostic tools, as well as in-depth clinical examinations.

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.

Epidemiology and surveillance of human (neuro)cysticercosis in Europe: is enhanced surveillance required?

OBJECTIVES

To report on relevant national surveillance systems of (N)CC and taeniasis (the infection with the adult tapeworm) in the European Union/European Economic Area and to assess the magnitude of (N)CC occurrence by retrieving information on cases for the period 2000-2016.

METHODS

(N)CC cases were retrieved via national reporting systems, a systematic literature search, contact with clinicians and a search for relevant 'International Statistical Classification of Diseases and Related Health Problems' (ICD)-based data.

RESULTS

Mandatory notification systems for (N)CC were found in Hungary, Iceland and Poland. Ten cases were reported in Poland and none in Hungary and Iceland. Through the systematic literature review and information given by clinicians, 263 individual and 721 aggregated (N)CC cases from 19 European countries were identified. ICD-based data were obtained from five countries. From 2000 to 2016, a total of 3489 cases (N)CC cases were coded: 832 in Italy, eight in Latvia, 357 in Portugal, 2116 in Spain and 176 in Sweden.

CONCLUSION

Despite being classified as a possible eradicable disease, (N)CC is still diagnosed across Europe, yet its true extent and impact remain unclear.

Microsurgical Treatment of Epilepsy with Parenchymal Neurocysticercosis

Parenchymal neurocysticercosis is the most common form of neurocysticercosis in the central nervous system (CNS), which mainly causes epilepsy and usually responses well to routine medications. However, there are appreciable cases of relapses refractory to medical treatment. We investigated microsurgical treatment of epilepsy with parenchymal neurocysticercosis. Nine cases of epilepsy caused by parenchymal neurocysticercosis from 2002 to 2018 were analyzed retrospectively. Cysts in 7 cases were completely removed. No case died of operation and no new dysfunction of the nervous system was observed after surgery. Among the other 9 cases, 8 cases became seizure-free or controlled by medicine according to the postoperative follow-up for 6 months to 9 years. One case was lost for follow-up. It was suggested that epilepsy with parenchymal neurocysticercosis can usually be controlled after routine medications. However, surgery is still indicated in some cases and careful microsurgery is associated with satisfactory clinical outcomes in appropriately selected cases.

Active neurocysticercosis at the Hospital for Tropical Diseases, London: a clinical case series

Background

Neurocysticercosis is the commonest infectious cause of epilepsy in endemic countries, and accounts for a greater number of cases worldwide than any other single pathology. Infection is associated with long-term exposure in low-income countries, although acquisition after travel has been recognized. The standard of care in the UK is inpatient treatment with anti-helminthic drugs and steroids.

Methods

The authors reviewed all cases of neurocysticercosis managed at the Hospital for Tropical Diseases in London, England, between 2001 and 2015. Active disease was defined as evidence of either viable cysts or involuting cysts with associated parenchymal inflammation.

Results

Of 26 active cases, 65.4% were migrants from nine different countries; 34.6% were UK-born travellers who had visited 19 countries across South and Central America, sub-Saharan Africa, South and South-east Asia; India was the commonest country of exposure in both groups. Only 73.1% presented with seizures; two diagnoses were made through brain imaging of patients with peripheral cysticerci; 53.8% had a single cyst. Migrants were more likely to be seropositive than travellers (p=0.033). Only two patients had seizures during admission, one of whom had multiple seizures prior to diagnosis.

Conclusions

Neurocysticercosis presents in a non-endemic setting in both migrants and travellers. Travellers are less likely to be sero-positive. Not all cases of neurocysticercosis present with seizures. Outpatient management could be considered for selected patients.

Taeniosis and cysticercosis in Serbia, 1990-2018: Significance of standard of living

OBJECTIVES

As is the case for all of Southeast Europe, Serbia is an area traditionally endemic for Taenia saginata and Taenia solium infections. This study was performed to analyse the epidemiological data on taeniosis and cysticercosis in Serbia for the period 1990-2018.

METHODS

Data on cases of T. saginata and T. solium infection were collected via a systematic search of published articles, the grey literature, and official reports, as well as by performing clinical observational studies of patients treated in the departments for infectious diseases of hospitals and university clinics in Serbia.

RESULTS

A total of 212 cases of taeniosis were reported, all between 1997 and 2004 when taeniosis was notifiable (incidence range 0.04-0.9/100 000 population/year). From 1990 to 2018, 170 cases of cysticercosis (all but one of neurocysticercosis), were registered (incidence range 0-0.29/100 000 population/year), with a strong decrease since 2000 and a single case in the last 9 years. The annual number of cases of both taeniosis (Pearson's r = 0.914, p =  0.001) and cysticercosis (Pearson's r = 0.582, p = 0.014) correlated with the consumer price index.

CONCLUSIONS

In Serbia, T. saginata and T. solium infections are autochthonous but occur only sporadically. However, the potential for re-emergence exists, depending on the socio-economic state of the country.

Epidemiology of central nervous system infectious diseases: a meta-analysis and systematic review with implications for neurosurgeons worldwide

OBJECTIVE

Central nervous system (CNS) infections cause significant morbidity and mortality and often require neurosurgical intervention for proper diagnosis and treatment. However, neither the international burden of CNS infection, nor the current capacity of the neurosurgical workforce to treat these diseases is well characterized. The objective of this study was to elucidate the global incidence of surgically relevant CNS infection, highlighting geographic areas for targeted improvement in neurosurgical capacity.

METHODS

A systematic literature review and meta-analysis were performed to capture studies published between 1990 and 2016. PubMed, EMBASE, and Cochrane databases were searched using variations of terms relating to CNS infection and epidemiology (incidence, prevalence, burden, case fatality, etc.). To deliver a geographic breakdown of disease, results were pooled using the random-effects model and stratified by WHO region and national income status for the different CNS infection types.

RESULTS

The search yielded 10,906 studies, 154 of which were used in the final qualitative analysis. A meta-analysis was performed to compute disease incidence by using data extracted from 71 of the 154 studies. The remaining 83 studies were excluded from the quantitative analysis because they did not report incidence. A total of 508,078 cases of CNS infections across all studies were included, with a total sample size of 130,681,681 individuals. Mean patient age was 35.8 years (range: newborn to 95 years), and the male/female ratio was 1:1.74. Among the 71 studies with incidence data, 39 were based in high-income countries, 25 in middle-income countries, and 7 in low-income countries. The pooled incidence of studied CNS infections was consistently highest in low-income countries, followed by middle- and then high-income countries. Regarding WHO regions, Africa had the highest pooled incidence of bacterial meningitis (65 cases/100,000 people), neurocysticercosis (650/100,000), and tuberculous spondylodiscitis (55/100,000), whereas Southeast Asia had the highest pooled incidence of intracranial abscess (49/100,000), and Europe had the highest pooled incidence of nontuberculous vertebral spondylodiscitis (5/100,000). Overall, few articles reported data on deaths associated with infection. The limited case fatality data revealed the highest case fatality for tuberculous meningitis/spondylodiscitis (21.1%) and the lowest for neurocysticercosis (5.5%). In all five disease categories, funnel plots assessing for publication bias were asymmetrical and suggested that the results may underestimate the incidence of disease.

CONCLUSIONS

This systematic review and meta-analysis approximates the global incidence of neurosurgically relevant infectious diseases. These results underscore the disproportionate burden of CNS infections in the developing world, where there is a tremendous demand to provide training and resources for high-quality neurosurgical care.

Epidemiology of taeniosis/cysticercosis in Europe, a systematic review: eastern Europe

BACKGROUND

Taenia solium and Taenia saginata are food-borne parasites of global importance. In eastern Europe only fragmented information is available on the epidemiology of these zoonotic parasites in humans and animal populations. In particular for T. solium, on-going transmission is suspected. The aim of this systematic review was to collect the available data and describe the current knowledge on the epidemiology of T. solium and T. saginata in eastern Europe.

METHODS

Literature published in international databases from 1990 to 2017 was systematically reviewed. Furthermore, local sources and unpublished data from national databases were retrieved from local eastern European experts. The study area included 22 countries.

RESULTS

Researchers from 18 out of the 22 countries provided data from local and unpublished sources, while no contacts could be established with researchers from Belarus, Kosovo, Malta and Ukraine. Taeniosis and human cysticercosis cases were reported in 14 and 15 out of the 22 countries, respectively. Estonia, the Former Yugoslav Republic of Macedonia, Lithuania, Moldova, Poland, Romania, Serbia, and Slovakia reported cases of porcine cysticercosis. Croatia, Czech Republic, Estonia, Former Yugoslav Republic of Macedonia, Moldova, Poland, Romania, Serbia, Slovakia, and Ukraine reported bovine cysticercosis.

CONCLUSIONS

There is indication that taeniosis and cysticercosis are present across eastern Europe but information on the occurrence of T. solium and T. saginata across the region remains incomplete. Available data are scarce and species identification is in most cases absent. Given the public health impact of T. solium and the potential economic and trade implications due to T. saginata, notification of taeniosis and human cysticercosis should be implemented and surveillance and notification systems in animals should be improved.

Human taeniasis/cysticercosis: a potentially emerging parasitic disease in Europe

Taenia saginata (T. saginata)/Taenia solium (T. solium) taeniasis/cysticercosis disease complexes remain a significant challenge for food safety and public health. Human taeniasis is an infectious disease caused by the ingestion of the metacestode larval stage, the cysticerci of T. saginata in beef or T. solium in pork. Humans can also become infected via the ingestion of T. solium eggs. In this case, the cysticerci can establish in the central nervous system, causing the infection called neurocysticercosis. T. solium is of higher importance than T. saginata because the former species can cause neurocysticercosis in humans, a major cause of neurological morbidity in the world. The taeniasis/cysticercosis complex is included in the list of neglected zoonotic diseases by the World Health Organization and Food and Agriculture Organization, with T. solium being the number one foodborne parasite; it occurs mostly in developing countries, such as regions of Asia, Africa and Latin America, where the disease remains endemic. Long absent in Western Europe and other developed countries, cysticercosis has been recently re-emerged as a result of immigration, travel and commerce. In this review, cysticercosis is presented with special emphasis on some aspects of this neglected disease: the main clinical manifestations, risk factors and epidemiology. In addition, any recent advances in diagnostic approaches and treatment are discussed. Finally, the complexities involved in the control of the disease and the need to revise current management strategies are highlighted.

Clinical Cysticercosis epidemiology in Spain based on the hospital discharge database: What's new?

BACKGROUND

Cysticercosis (CC) is a tissue infection caused by the larval cysts of the pork tapeworm Taenia solium. It is usually acquired by eating contaminated food or drinking water. CC Cysts can develop in the muscles, the eyes, the brain, and/or the spinal cord. T. solium is found worldwide, but its prevalence has decreased in developed countries due to stricter meat inspection and better hygiene and sanitation. Nevertheless, CC is still a leading cause of seizures and epilepsy. In Spain, The disease is not nationally reportable and data on CC infected animals are also missing, despite the European Directive 2003/99/EC.

METHODOLOGY/PRINCIPAL FINDINGS

We performed a retrospective descriptive study using the Spanish Hospitalization Minimum Data Set (CMBD). Data with ICD-9 CM cysticercosis code ("123.1") placed in first or second diagnostic position from 1997 to 2014 were analyzed. Hospitalization rates were calculated and clinical characteristics were described. Spatial distribution of cases and their temporal behavior were also assessed. A total of 1,912 hospital discharges with clinical cysticercosis were identified. From 1998 to 2008, an increasing trend in the number of CC hospitalizations was observed, decreasing afterwards, in parallel with a decrease in the external migration rate. The Murcia region had the highest median hospitalization rate (13.37 hospitalizations/100,000 population), followed by Navarra and Madrid. The 16-44 age group was the most represented (63.6%). The three most frequent associated diagnoses were epilepsy and convulsions (49.5%), hydrocephalus (11.8%) and encephalitis/myelitis/meningitis (11.6%).

CONCLUSIONS/SIGNIFICANCE

There is a need for a common strategy on data collection, monitoring and reporting, which would facilitate a more accurate picture on the CC epidemiological scenario. Even if most cases might be imported, improving the human and animal CC surveillance will result useful both in gaining extended disease knowledge and reducing morbidity and related-costs.

One Health-ness Evaluation of Cysticercosis Surveillance Design in Portugal

The increasing occurrence of human cysticercosis, a zoonotic neglected disease, is challenging the traditional prevention and control paradigm and calling for One Health (OH) solutions in industrialized countries. OH solutions for health interventions are increasingly being used to capture expected and unexpected outcomes across people, animals, and the environment. The Network for Evaluation of One Health (NEOH) proposes an evidence-based framework, relying on systems and mixed methods approaches to evaluate the One Health-ness. In this case study, this tool is used to evaluate the design of the Observatory of Taeniasis and Cysticercosis, as an example of intersectorial collaboration for surveillance in Portugal. The OH Initiative (drivers and expected outcomes) and its system (boundaries, aim, dimensions, actors, and stakeholders) were described. The different aspects of this Initiative were scored with values from 0 (=no OH approach) to 1 (=perfect OH approach). The OH index was 0.31. Its OH ratio is 1.98. Overall scores were as follows: OH thinking 0.75; OH planning 0.60; OH working 0.60; OH sharing 0.35; OH learning 0.50; and systemic organization 0.50. Operational levels of the Initiative are the main strengths, indicating a comprehensive multidimensional innovative approach and transdisciplinarity. Critical issues in the supporting infrastructure were observed, related to communication, learning and organizational gaps in the project, with the evaluation being conducted as the project is being designed and implemented. The strengths and weaknesses detected may be used to refine the Initiative. This case study therefore exemplifies and supports OH assessment also for ongoing projects, at design and early implementation stages for guiding and guaranteeing an OH-oriented perspective.

Spontaneously Arrested Transmission of Cysticercosis in a Highly Endemic Village with a Very Low Migration Rate

Taenia solium cysticercosis is difficult to eliminate without interventions or societal development. Atahualpa is a rural Ecuadorian village with documented low migration rate, where domestic pig raising is common and human cysticercosis is endemic. To assess neurocysticercosis (NCC) prevalence, 1,273 villagers aged ≥ 20 years underwent neuroimaging studies, which showed calcified lesions in 121 (9.5%) individuals, but no active disease. Likewise, positive reactions, apparently nonspecific, were found in only 3/200 subjects by the use of a monoclonal antibody-based enzyme-linked immunosorbent assay to detect T. solium antigens in urine. Only 2/418 pigs reacted to three antibody bands on serum western blot and none to more than three bands. This is the first time that spontaneously arrested T. solium transmission is documented in a known endemic village. Understanding why active transmission stopped could provide insights on potential targets for control interventions. Atahualpa could provide an optimal scenario for longitudinal studies on the consequences of calcified NCC.

Prevalence of cysticercosis in Estonian pigs and cattle

Taenia solium has been ranked as the most important foodborne parasite and Taenia saginata as the most commonly found human Taenia tapeworm worldwide. The last official reports of taeniosis from Estonia were in 2003 for T. solium and 2012 for T. saginata. By law, all animal cases of cysticercosis must be registered and reported when found. Our aim was to estimate the prevalence of cysticercosis in Estonia caused by T. solium in pigs and T. saginata in cattle. The four slaughterhouses participating in the study slaughter between them approximately 80% of pigs and cattle in Estonia annually. Sampling spanned from February to April 2014, visiting the slaughterhouses five times per week. Visual inspection, palpation, and incisions at predilection sites were used to find cysts in both species. The sites inspected in both species were the external masseter, tongue, heart, and diaphragm. In addition, the internal masseter in pigs was examined, and the internal pterygoid muscle and esophagus in cattle. DNA was extracted from the cysts and used for PCR amplification of the cox1-gene for Taenia genus and species identification. A total of 564 cattle and 1217 pigs were examined. Cysts were found in 0.36% (n = 2; CI 0.06-1.17) of cattle and in 0.08% (n = 1; CI 0.004-0.40) of pigs. Cestode PCR was negative from all cysts. Results should be considered taking into account the low sensitivity and specificity of finding cysts. Results reflect the situation in larger slaughterhouses, and the possibility that the situation in smaller slaughterhouses is different should not be excluded.

Understanding the association of neurocysticercosis and mesial temporal lobe epilepsy and its impact on the surgical treatment of patients with drug-resistant epilepsy

Mesial temporal lobe epilepsy associated with hippocampal sclerosis (MTLE-HS) is one of the most common types of focal epilepsies. This is an epileptic syndrome commonly associated with treatment-resistant seizures, being also the most prevalent form of drug-resistant epilepsy which is treated surgically in most epilepsy surgery centers. Neurocysticercosis (NCC) is one of the most common parasitic infections of the central nervous system, and one of the most common etiological agents of focal epilepsy, affecting millions of patients worldwide. Recently, researchers reported a curious association between MTLE-HS with NCC, but this association remains poorly understood. Some argue that calcified NCC lesions in MTLE-HS patients is only a coincidental finding, since both disorders are prevalent worldwide. However, others suppose there might exist a pathogenic relationship between both disorders and some even suspect that NCC, by acting as an initial precipitating injury (IPI), might cause hippocampal damage and, eventually, MTLE-HS. In this review, we discuss the various reports that examine this association, and suggest possible explanations for why calcified NCC lesions are also observed in patients with MTLE-HS. We also propose mechanisms by which NCC could lead to MTLE-HS. Finally, we discuss the implications of NCC for the treatment of pharmacologically-resistant focal epilepsies in patients with calcified NCC or in patients with MTLE-HS and calcified NCC lesions. We believe that investigations in the relationship between NCC and MTLE-HS might offer further insights into how NCC may trigger epilepsy, and into how MTLE-HS originates. Moreover, observations in patients with drug-resistant epilepsy with both NCC and hippocampal sclerosis may not only aid in the understanding and treatment of patients with MTLE-HS, but also of patients with other forms of dual pathologies aside from NCC. This article is part of a Special Issue titled Neurocysticercosis and Epilepsy.

Epidemiology of taeniosis/cysticercosis in Europe, a systematic review: Western Europe

BACKGROUND

Taenia solium and Taenia saginata are zoonotic parasites of public health importance. Data on their occurrence in humans and animals in western Europe are incomplete and fragmented. In this study, we aimed to update the current knowledge on the epidemiology of these parasites in this region.

METHODS

We conducted a systematic review of scientific and grey literature published from 1990 to 2015 on the epidemiology of T. saginata and T. solium in humans and animals. Additionally, data about disease occurrence were actively sought by contacting local experts in the different countries.

RESULTS

Taeniosis cases were found in twelve out of eighteen countries in western Europe. No cases were identified in Iceland, Ireland, Luxembourg, Norway, Sweden and Switzerland. For Denmark, Netherlands, Portugal, Slovenia, Spain and the UK, annual taeniosis cases were reported and the number of detected cases per year ranged between 1 and 114. Detected prevalences ranged from 0.05 to 0.27%, whereas estimated prevalences ranged from 0.02 to 0.67%. Most taeniosis cases were reported as Taenia spp. or T. saginata, although T. solium was reported in Denmark, France, Italy, Spain, Slovenia, Portugal and the UK. Human cysticercosis cases were reported in all western European countries except for Iceland, with the highest number originating from Portugal and Spain. Most human cysticercosis cases were suspected to have acquired the infection outside western Europe. Cases of T. solium in pigs were found in Austria and Portugal, but only the two cases from Portugal were confirmed with molecular methods. Germany, Spain and Slovenia reported porcine cysticercosis, but made no Taenia species distinction. Bovine cysticercosis was detected in all countries except for Iceland, with a prevalence based on meat inspection of 0.0002-7.82%.

CONCLUSIONS

Detection and reporting of taeniosis in western Europe should be improved. The existence of T. solium tapeworm carriers, of suspected autochthonous cases of human cysticercosis and the lack of confirmation of porcine cysticercosis cases deserve further attention. Suspected cases of T. solium in pigs should be confirmed by molecular methods. Both taeniosis and human cysticercosis should be notifiable and surveillance in animals should be improved.

Present status of laboratory diagnosis of human taeniosis/cysticercosis in Europe

Human cysticercosis (CC) is a parasitic zoonosis caused by the larval stage (cyst) of the Taenia solium. Cysts can establish in the human central nervous system (neurocysticercosis, NCC) and other organs and tissues; they also develop in pigs, the natural intermediate host. Human taeniosis may be caused by T. solium, Taenia saginata and Taenia asiatica tapeworms; these infections are usually asymptomatic, but show a significant relevance as they perpetuate the parasites’ life cycle, and, in the case of T. solium, they are the origin of (N)CC. In European Union (EU) member states and associated countries, the occurrence of autochthonous T. solium cases is debated, and imported cases have significantly increased lately; the status of T. asiatica has been never reported, whereas T. saginata is prevalent and causes an economic impact due to condemned carcasses. Based on their effects on the EU society, the specific diagnosis of these pathologies is relevant for their prevention and control. The aims of this study were to know the diagnostic tests used in European laboratories for human taeniosis/cysticercosis by means of a questionnaire, to determine potential gaps in their detection, and to obtain preliminary data on the number of diagnosed taeniosis/CC cases.

Geo-helminthiasis among migrants in Sicily: a possible focus for re-emerging neurocysticercosis in Europe

A dramatic increasing immigration flow was recorded in Europe during the last years. Only in Sicily 120,239 people arrived in 2014. Immigrants may carry neglected tropical diseases endemic in their origin countries. The aim of our study was to evaluate the frequency of geo-helminthiasis, and in particular of intestinal taeniasis, in a sample of migrants hosted in a large asylum seeker centre in the province of Catania. A stool sample was obtained from all the enrolled subjects and a coproparasitological examination was performed. Out of the 274 enrolled subjects (249 men; mean age 26.4 ± 6.2), 30 (11%) carried at least one helminthic infestation. Ancylostomatidae, Trichuris trichiura and Taenia species (spp) were the most common, the latter found in 6 (2.16%) subjects. T. solium carriers can represent a focus of infection for the more complex neurocysticercosis. Even if coproparasitological examination did not allow us to differentiate Taenia spp, we cannot exclude the presence of T. solium carriers among these subjects. Further studies, including coproantigen ELISA to detect Taenia spp, should be carried out in larger samples to better estimate the real burden of T. solium carriers.

Changes in the seroprevalence of cysticercosis in suspected patients in Chandigarh, India between 1998 and 2014: analysis of 17 years of data

Changes in seroprevalence of cysticercosis diagnosed in Chandigarh, India between 1998 and 2014 were investigated by extraction and analysis of data from records held at the Postgraduate Institute of Medical Education and Research in Chandigarh. Among the total number of samples for which cysticercosis had been suspected during this period (N = 9650), 1716 (17·8%) were seropositive. Adults were more likely to be seropositive than children, and women were more likely to be seropositive than men. In addition to there being fewer patients with suspicion of cysticercosis over the data analysis period, the proportion of patients seropositive also reduced significantly. Despite these reductions, which are probably associated with improved infrastructure and sanitation within Chandigarh, and despite meat consumption being relatively rare in this area, the extent of cysticercosis in this population remains problematic. Further efforts should be made to reduce transmission of this infection, with particular emphasis on women. Such efforts should follow the One Health concept, and involve medical efforts (including diagnosis and treatment of T. solium tapeworm carriers), veterinary efforts directed towards meat inspection and prevention of infection of pigs, and environmental health and sanitation engineers (to minimize environmental contamination with human waste).

Reprint of "Neurocysticercosis-related mortality in Brazil, 2000-2011: Epidemiology of a neglected neurologic cause of death"

Neurocysticercosis (NCC) is an important cause of severe neurological disease mainly in low- and middle-income countries, but data on NCC mortality from endemic areas are scarce. Here we analysed the epidemiological patterns of NCC-related mortality in Brazil. We included all deaths recorded in Brazil between 2000 and 2011, in which NCC was mentioned on death certificates, either as underlying or as associated cause of death. NCC was identified in 1829/12,491,280 deaths (0.015%), 1130 (61.8%) as underlying cause, and 699 (38.2%) as associated cause. Overall age-adjusted mortality rate for the period was 0.97 deaths/1,000,000 inhabitants (95% confidence interval [CI]: 0.83-1.12). The highest NCC-related mortality rates were found in males, elderly, white race/colour and residents in endemic states/regions. Age-adjusted mortality rates at national level decreased significantly over time (annual percent change [APC]: -4.7; 95% CI: -6.0 to -3.3), with a decrease in the Southeast, South and Central-West regions, and a non-significant increasing trend in the North and Northeast regions. We identified spatial and spatiotemporal high-risk mortality clusters located mainly in NCC-endemic areas. Conditions related to the nervous system were the most commonly associated causes of death when NCC was mentioned as an underlying cause, and HIV/AIDS was the main underlying cause when NCC was an associated cause. NCC is a neglected and preventable cause of severe neurologic disease and death with high public health impact in Brazil. There is a clear need to strengthen nationwide epidemiological surveillance and control for the taeniasis/cysticercosis complex.

Taenia solium in Europe: Still endemic?

The pork tapeworm, Taenia solium, causes an important economic and health burden, mainly in rural or marginalized communities of sub-Saharan Africa, Asia, and Latin-America. Although improved pig rearing conditions seem to have eliminated the parasite in most Western European countries, little is known about the true endemicity status of T. solium throughout Europe. Three recent reviews indicate that autochthonous human T. solium taeniasis/cysticercosis may be possible in Europe, but that current peer-reviewed literature is biased towards Western Europe. Officially reported data on porcine cysticercosis are highly insufficient. Favourable conditions for local T. solium transmission still exist in eastern parts of Europe, although the ongoing integration of the European Union is speeding up modernisation and intensification of the pig sector. Further evidence is urgently needed to fill the gaps on the European T. solium endemicity map. We urge to make human cysticercosis notifiable and to improve the reporting of porcine cysticercosis.

Different clinical allergological features of Taenia solium infestation

The tapeworm Taenia (T.) solium can be responsible for two different conditions: taeniasis and cysticercosis. Helminth infections in human host cause an immune response associated with elevated levels of IgE, tissue eosinophilia and mastocytosis, and with the presence of CD4+ T cells that preferentially produce IL-4, IL-5, and IL-13. Individuals exposed to helminth infections may have allergic inflammatory responses to parasites and parasite antigens. PubMed search of human cases of allergic reactions occurring during T. solium infestation was performed combining the terms (allergy, urticaria, angioedema, asthma, anaphylaxis) with T. solium. A study was considered eligible for inclusion in the review if it reported data on patients with T. solium infestation who had signs or symptoms of allergy. In literature we found six articles reporting the association between an allergic reaction and T. solium infestation: two cases of urticaria, two cases of relapsing angioedema, one case of asthma and two cases of anaphylaxis. Despite the large diffusion of T. solium infestation, we found only a few cases of concomitant allergic reaction and the presence of Taenia in the host. The association between T. solium infestation and allergic manifestations has never been clearly demonstrated, and in absence of a well-documented causality the hypotheses are merely speculative. Therefore, the association between Taenia infection and allergy needs to be thoroughly studied to better clarify if this association may really exist and which is the pathogenetic mechanism supported.

Human cysticercosis in Portugal: long gone or still contemporary?

Cysticercosis, a leading cause of acquired epilepsy in developing countries, has been controlled or eradicated in industrialized countries. This paradigm has recently been challenged, with human neurocysticercosis (NCC) being increasingly diagnosed in these countries. In order to assess the NCC burden in Portugal, a retrospective study on NCC hospitalizations (2006–2013) was conducted based on the national database on hospital morbidity: 357 hospitalized cases were detected. NCC was most frequent in the following age groups: 20–64 years (n = 197, 55·2%) >64 years (n = 111, 31·1%), and <20 years (n = 49, 13·7%). In the Norte and Centro regions cases tended to be older than in the Lisboa and Vale do Tejo Region. The results raise concerns for imported and autochthonous disease, suggesting the Lisboa and Vale do Tejo Region, due to its higher frequency of cases at younger ages, as a priority for research and intervention, and further suggest that NCC should be under surveillance (notifiable). The National Observatory of Cysticercosis and Taeniasis has been established and will define NCC cases as well as monitoring and surveillance.

Neurocysticercosis-related mortality in Brazil, 2000-2011: Epidemiology of a neglected neurologic cause of death

Neurocysticercosis (NCC) is an important cause of severe neurological disease mainly in low- and middle-income countries, but data on NCC mortality from endemic areas are scarce. Here we analysed the epidemiological patterns of NCC-related mortality in Brazil. We included all deaths recorded in Brazil between 2000 and 2011, in which NCC was mentioned on death certificates, either as underlying or as associated cause of death. NCC was identified in 1829/12,491,280 deaths (0.015%), 1130 (61.8%) as underlying cause, and 699 (38.2%) as associated cause. Overall age-adjusted mortality rate for the period was 0.97 deaths/1,000,000 inhabitants (95% confidence interval [CI]: 0.83-1.12). The highest NCC-related mortality rates were found in males, elderly, white race/colour and residents in endemic states/regions. Age-adjusted mortality rates at national level decreased significantly over time (annual percent change [APC]: -4.7; 95% CI: -6.0 to -3.3), with a decrease in the Southeast, South and Central-West regions, and a non-significant increasing trend in the North and Northeast regions. We identified spatial and spatiotemporal high-risk mortality clusters located mainly in NCC-endemic areas. Conditions related to the nervous system were the most commonly associated causes of death when NCC was mentioned as an underlying cause, and HIV/AIDS was the main underlying cause when NCC was an associated cause. NCC is a neglected and preventable cause of severe neurologic disease and death with high public health impact in Brazil. There is a clear need to strengthen nationwide epidemiological surveillance and control for the taeniasis/cysticercosis complex.

Under seize: neurocysticercosis in an immigrant woman and review of a growing neglected disease

Neurocysticercosis (NCC) is a significantly neglected tropical disease and, with increasing globalisation, a notable emerging infection in the developed world. We describe a case of ventricular NCC in a 22-year-old Mexican-American woman with a history of seizures, who presented with 2 weeks of headaches and intermittent fevers progressing to altered mental status and vomiting. Initial imaging revealed a cystic mass at the posteroinferior aspect of the third ventricle superior to the aqueduct of Sylvius, calcifications scattered throughout the parenchyma, and enlargement of the lateral and third ventricles. Initial laboratories were unrevealing and serum investigations for Taenia solium antibody were negative, but T. solium antibody was subsequently returned positive from cerebrospinal fluid. This case highlights important issues regarding the clinical presentation, diagnostic evaluation and treatment of NCC relevant to providers not only in areas with endemic disease but, importantly, in locales with diverse immigrant populations.

An Unusual Presentation of Neurocysticercosis: A Space-Occupying Lesion in the Fourth Ventricle Associated with Progressive Cognitive Decline

We communicate a case of a middle-aged Brazilian patient with an unusual presentation of fourth ventricular neurocysticercosis: occurrence of two intraventricular cysts at different locations in the brain within 2 years and cognitive decline as the only neurological symptom. Neurocysticercosis was confirmed by magnetic resonance imaging, serology, histology, and genetic analysis. Neurocysticercosis should be considered as a differential diagnosis in cases with atypical neurologic or psychiatric symptoms, atypical neuroimaging and travel history. Especially, fourth ventricular cysts carry the risk of obstructive hydrocephalus and brainstem compression and therefore should be extirpated completely. If complete removal of the cystic structures cannot be proven in cases with surgically treated neurocysticercosis, anthelminthic therapy and thorough follow-up examinations should be conducted.

[Giant racemose subarachnoid and intraventricular neurocysticercosis: A case report]

Neurocysticercosis is the most frequent parasitic disease of the central nervous system. It is caused by the larvae of Taenia solium, which can affect different anatomical sites. In Spain there is an increasing prevalence mainly due to immigration from endemic areas. The extraparenchymal forms are less common, but more serious because they usually develop complications. Neuroimaging plays a major role in the diagnosis and follow-up of this disease, supported by serology and a compatible clinical and epidemiological context. First-line treatments are cysticidal drugs such as albendazole and praziquantel, usually coadministered with corticosteroids, and in some cases surgery is indicated. We here report a case of neurocysticercosis with simultaneous intraventricular and giant racemose subarachnoid involvement.

Human migration and pig/pork import in the European Union: What are the implications for Taenia solium infections?

Taenia solium taeniasis/cysticercosis is a neglected zoonotic disease complex occurring primarily in developing countries. Though claimed eradicated from the European Union (EU), an increasing number of human neurocysticercosis cases is being detected. Risk factors such as human migration and movement of pigs/pork, as well as the increasing trend in pig rearing with outside access are discussed in this review. The entry of a tapeworm carrier into the EU seems a lot more plausible than the import of infected pork. The establishment of local transmission in the EU is presently very unlikely. However, considering the potential changes in risk factors, such as the increasing trend in pig farming with outdoor access, the increasing human migration from endemic areas into the EU, this situation might change, warranting the establishment of an early warning system, which should include disease notification of taeniasis/cysticercosis both in human and animal hosts. As currently human-to-human transmission is the highest risk, prevention strategies should focus on the early detection and treatment of tapeworm carriers, and should be designed in a concerted way, across the EU and across the different sectors.

Neurocysticercosis

Neurocysticercosis, the most common helminthic infection of the nervous system, is a major cause of acquired epilepsy worldwide. The disease occurs when humans become intermediate hosts of the tapeworm Taenia solium after ingesting its eggs by contagion from an asymptomatic Taenia carrier. Within the nervous system, parasites may locate in brain parenchyma, subarachnoid space, ventricular system, or spinal cord, causing several pathological changes that are responsible for the clinical pleomorphism of the disease. Seizures are the most common clinical manifestation, but a sizable proportion of patients develop focal deficits, intracranial hypertension, or cognitive decline. Preoperative diagnosis of neurocysticercosis is possible after proper integration of data from neuroimaging studies and immunological tests. Cysticidal drugs (albendazole and praziquantel) have changed the prognosis of most patients with neurocysticercosis. The use of these drugs has shown to reduce the parasite load within the central nervous system and to improve the clinical prognosis of the disease in many cases. Future studies should focus on disease eradication through the implementation of control programs against all the interrelated steps in the life cycle of T solium, including human carriers of the adult tapeworm, infected pigs, and eggs in the environment.

Three cases of imported neurocysticercosis in Northern Italy

BACKGROUND

Neurocysticercosis (NCC) is an important cause of adult-onset seizures in endemic areas, whereas it is emerging in some nonendemic areas as well because of extensive immigration.

METHOD

We describe three cases of imported NCC recently admitted to San Bortolo Hospital in Vicenza, located in Northern Italy.

RESULTS

All patients were immigrants. One patient was human immunodeficiency virus positive with severe immunosuppression. The diagnosis of NCC was made on the basis of magnetic resonance results; failure of anti-Toxoplasma, antitubercular, and antifungal therapy; and regression of the cystic lesions after empiric therapy with albendazole. Serology was positive in only one case. In one patient, NCC was diagnosed by biopsy of the brain lesion.

CONCLUSION

In nonendemic countries, NCC should be included in the differential diagnosis of all patients coming from endemic areas with seizures, hydrocephalus, and compatible lesions on brain imaging. Long-term follow-up is required but may be difficult to implement because these patients tend to move in search of employment. Screening of patient's household contacts for Taenia solium infection should always be carried out.

Neurocysticercosis

Known as a disease of swine in ancient civilizations, cysticercosis is currently considered the most common helminthic infection of the nervous system, and a leading cause of acquired epilepsy worldwide. The disease occurs when humans become intermediate hosts of the tapeworm Taenia solium by ingesting its eggs from contaminated food or, most often, directly from a Taenia carrier by the fecal-oral route. Once in the human intestine, Taenia eggs evolve to oncospheres that, in turn, cross the intestinal wall and lodge in human tissues - especially the nervous system - where cysticerci develop. The brain is a hostile environment in which parasites attempt to escape the immune surveillance while the host is trying to drive out the infection. In some cases, cysticerci are destroyed by this immunological attack, while in others, parasites may live unchanged for years. Cysticerci may be located in brain parenchyma, subarachnoid space, ventricular system, or spinal cord, causing a myriad of pathologic changes that are the main changes responsible for the clinical pleomorphism of neurocysticercosis. Seizures are the most common clinical manifestation of the disease, but some patients present with focal deficits, intracranial hypertension, or cognitive decline. With the exception of cystic lesions showing the scolex as an eccentric nodule, neuroimaging findings of neurocysticercosis are nonspecific and may be seen in other diseases of the nervous system. Likewise, immune diagnostic tests have been faced with problems related to poor sensitivity or specificity. Accurate diagnosis is possible after interpretation of clinical data together with findings of neuroimaging studies and results of immunologic tests, in a proper epidemiologic scenario. The introduction of cysticidal drugs has changed the prognosis of neurocysticercosis. Praziquantel and albendazole have been shown to reduce the burden of infection in the brain (as seen on neuroimaging studies) and to improve the clinical course of the disease in most patients. Further efforts should be directed towards eradicating this disease through the implementation of control programs for all the interrelated steps in the life cycle of T. solium, including human carriers of the adult tapeworm, infected pigs, and eggs in the environment.

Neurocysticercosis: new thoughts on controversial issues

PURPOSE OF REVIEW

This review comments on the recent advances in the understanding of the controversial aspects of neurocysticercosis (NCC).

RECENT FINDINGS

The number of autochthonous cases of NCC in nonendemic countries has increased during the last few years: it is likely that the migration of Taenia carriers from endemic areas is responsible for the increased prevalence of locally acquired NCC in these regions. NCC is mostly acquired from person to person, and the old theories crediting the environment as the main source of human infection with Taenia solium eggs must be abandoned. There is growing evidence suggesting that cysticercus granulomas (one of the most common forms of presentation of NCC) represent fresh infections and not old infections resulting from spontaneous destruction of viable cysticerci. Calcifications, often seen as inactive lesions producing no symptoms, are responsible for a sizable proportion of NCC-related seizures or headache. It is likely that exposure of parasitic antigens to the host's immune system is the cause of these manifestations.

SUMMARY

During the last few years, there has been an increased knowledge on the controversial aspects of NCC, including epidemiology, mechanisms of disease acquisition, the natural involution of lesions in the brain parenchyma, and the role of calcifications as responsible for symptom occurrence.

Evidence of human neurocysticercosis in Slovenia

To assess the prevalence of Taenia solium cysticercosis in patients with neurological disorders in Slovenia, serum/cerebrospinal fluid (CSF) samples from 348 suspected patients were collected between the beginning of January 2001 and the end of December 2012 and analysed serologically for the presence of anti-T. solium IgG antibodies. Of 20 patients whose samples tested positive or equivocal by enzyme-linked immunosorbent assay (ELISA), samples of 7 patients were confirmed positive by Western blot (WB). The overall seroprevalence rate of T. solium infection in patients with neurological disorders included in the study was 2.0%. Serological results of positive patients corresponded to clinical and/or imaging findings concerning their brain cysts. Based on their personal data, it was ascertained that neurocysticercosis (NCC) positive patients had immigrated or came to Slovenia from the former Yugoslav republics. Since the disease is believed not to be endemic in Slovenia we assume that all of the NCC-positive patients had acquired the infection before immigration to Slovenia or visiting or being visited by their relatives infected with an adult T. solium parasite. The present results represent the first insight into the prevalence of NCC in patients with neurological disorders in Slovenia.

Neurocysticercosis in Europe: Still a public health concern not only for imported cases

Neurocysticercosis (NCC), a parasitic disease caused by the larvae of the cestode Taenia solium, is the most frequent parasitic disease of the central nervous system (CNS) in the world and the leading cause of secondary epilepsy in Central and South America, East and South Asia, and sub-Saharan Africa. It is endemic in many low- and middle-income countries of the world. Due to increased travels and immigration, NCC may be diagnosed also in non-endemic areas. In fact, tapeworm carriers from endemic zones can transmit infection to other citizens or arrive already suffering NCC. This phenomenon, occurred first in USA during the last 30 years, has been also observed in Europe, as well as in Australia, Canada, Israel, Japan and Muslim countries of the Arab World. Actually, concerning Europe, although, in some areas only few cases have been described, nevertheless the prevalence of NCC may be considered increasing, especially in Spain and Portugal. We reviewed the literature on the burden of NCC in Europe, by a search of PubMed regarding papers from 1970 to present. We only considered on PubMed published and available papers in English, French, Italian, and Spanish, the languages understood by the authors. One hundred seventy six cases of NCC have been reported in seventeen European countries (Austria, Belgium, Denmark, Finland, France, Germany, Greece, Hungary, Ireland, Italy, Latvia, Netherlands, Sweden, United Kingdom, and Croatia, Norway, Switzerland). A particular epidemic situation is present in Spain and Portugal. In fact, we collected data that show, in Spain, an increasing incidence both in immigrated patients and in those which were born in certain Spanish geographical areas and, in Portugal, prevalence similar to that observed in endemic areas. Globally, it is clear that as a result of increased migrations and travels from endemic regions, NCC is becoming an emerging public health problem in high-income countries, particularly affecting communities where hygiene conditions are poor and sub-sequentially the parasite can spread from human to human through eggs even in absence of a travel to the tropics. NCC is a preventable disease, it derives that it's important to acquire a great consciousness of the epidemiology and to implement accurate surveillance systems.

Epidemiology and management of cysticercosis and Taenia solium taeniasis in Europe, systematic review 1990-2011

BACKGROUND

Cysticercosis is caused by the invasion of human or pig tissues by the metacestode larval stage of Taenia solium. In Europe, the disease was endemic in the past but the autochthonous natural life cycle of the parasite is currently completed very rarely. Recently, imported cases have increased in parallel to the increased number of migrations and international travels. The lack of specific surveillance systems for cysticercosis leads to underestimation of the epidemiological and clinical impacts.

OBJECTIVES

To review the available data on epidemiology and management of cysticercosis in Europe.

METHODS

A review of literature on human cysticercosis and T. solium taeniasis in Europe published between 1990-2011 was conducted.

RESULTS

Out of 846 cysticercosis cases described in the literature, 522 cases were autochthonous and 324 cases were imported. The majority (70.1%) of the autochthonous cases were diagnosed in Portugal from 1983 and 1994. Imported cases of which 242 (74.7%) diagnosed in migrants and 57 (17.6%) in European travellers, showed an increasing trend. Most of imported cases were acquired in Latin America (69.8% of migrants and 44.0% of travellers). The majority of imported cases were diagnosed in Spain (47.5%), France (16.7%) and Italy (8.3%). One third of neurosurgical procedures were performed because the suspected diagnosis was cerebral neoplasm. Sixty eight autochthonous and 5 imported T. solium taeniasis cases were reported.

CONCLUSIONS

Cysticercosis remains a challenge for European care providers, since they are often poorly aware of this infection and have little familiarity in managing this disease. Cysticercosis should be included among mandatory reportable diseases, in order to improve the accuracy of epidemiological information. European health care providers might benefit from a transfer of knowledge from colleagues working in endemic areas and the development of shared diagnostic and therapeutic processes would have impact on the quality of the European health systems.

Neurocysticercosis in infants and toddlers: report of seven cases and review of published patients

Neurocysticercosis in infants and toddlers has received little attention in the literature, and little is known about the mechanisms of disease acquisition and clinical forms of presentation of the disease in this age group. All patients aged ≤3 years with neurocysticercosis evaluated at Hospital-Clínica Kennedy, Guayaquil, over a 22-year period were included in this study. Their household contacts were screened to detect Taenia solium carriers, which may represent the source of infection. A literature search on neurocysticercosis in infants and toddlers was also performed to compare personal cases with those described elsewhere. A total of 25 infants and toddlers with neurocysticercosis were included (seven from our institution and 18 from the literature). All patients had seizures as the primary manifestation of the disease, and neuroimaging studies showed one or two parenchymal brain cysticerci in the colloidal stage in 88% of patients. The source of infection was investigated in 11 houses, including the seven households of the present series, and only four of the 18 reported in the literature. A Taenia carrier was found in five (45%) of these households, including three from the present series and two from the literature. A sizable proportion of infants and toddlers with neurocysticercosis have been infected at home. Compulsory search of Taenia carriers among household contacts will allow the detection of the potential source of infection and will reduce further spread of the disease. The search must not be limited to family members, but also extended to domestic employees who are in daily contact with the children.

Diagnostic criteria for neurocysticercosis, revisited

Diagnosis of neurocysticercosis (NCC) can be a challenge. Clinical manifestations are non-specific, most neuroimaging findings are non-pathognomonic, and some serologic tests have low sensitivity or specificity. A set of diagnostic criteria was proposed in 2001 to avoid the over diagnosis of NCC that occurs in epidemiologic surveys, and to help clinicians evaluating patients with suspected NCC. The set included four stratified categories of criteria, including: (1) absolute: histological demonstration of cysticerci, cystic lesions showing the scolex on neuroimaging studies, and direct visualization of subretinal parasites by fundoscopic examination; (2) major: lesions highly suggestive of NCC on neuroimaging studies, positive serum enzyme-linked immunoelectrotransfer blot (EITB) for the detection of anticysticercal antibodies, resolution of intracranial cystic lesions after cysticidal drug therapy, and spontaneous resolution of single enhancing lesions; (3) minor: lesions compatible with NCC on neuroimaging studies, suggestive clinical manifestations, positive cerebrospinal fluid (CSF) ELISA for detection of anticysticercal antibodies or cysticercal antigens, and cysticercosis outside the nervous system; and (4) epidemiological: evidence of a household contact with Taenia solium infection, individuals coming from or living in cysticercosis endemic areas, and history of travel to disease-endemic areas. Interpretation of these criteria permits two degrees of diagnostic certainty: (1) definitive diagnosis, in patients who have one absolute criterion or in those who have two major plus one minor and one epidemiological criteria; and (2) probable diagnosis, in patients who have one major plus two minor criteria, in those who have one major plus one minor and one epidemiological criteria, and in those who have three minor plus one epidemiological criteria. After 10 years of usage, this set has been proved useful in both, field studies, and hospital settings. Recent advances in neuroimaging and immune diagnostic methods have enhanced its accuracy for the diagnosis of NCC.

Central Nervous System Infections

Central nervous system (CNS) infections—i.e., infections involving the brain (cerebrum and cerebellum), spinal cord, optic nerves, and their covering membranes—are medical emergencies that are associated with substantial morbidity, mortality, or long-term sequelae that may have catastrophic implications for the quality of life of affected individuals. Acute CNS infections that warrant neurointensive care (ICU) admission fall broadly into three categories—meningitis, encephalitis, and abscesses—and generally result from blood-borne spread of the respective microorganisms. Other causes of CNS infections include head trauma resulting in fractures at the base of the skull or the cribriform plate that can lead to an opening between the CNS and the sinuses, mastoid, the middle ear, or the nasopharynx. Extrinsic contamination of the CNS can occur intraoperatively during neurosurgical procedures. Also, implanted medical devices or adjunct hardware (e.g., shunts, ventriculostomies, or external drainage tubes) and congenital malformations (e.g., spina bifida or sinus tracts) can become colonized and serve as sources or foci of infection. Viruses, such as rabies, herpes simplex virus, or polioviruses, can spread to the CNS via intraneural pathways resulting in encephalitis. If infection occurs at sites (e.g., middle ear or mastoid) contiguous with the CNS, infection may spread directly into the CNS causing brain abscesses; alternatively, the organism may reach the CNS indirectly via venous drainage or the sheaths of cranial and spinal nerves. Abscesses also may become localized in the subdural or epidural spaces. Meningitis results if bacteria spread directly from an abscess to the subarachnoid space. CNS abscesses may be a result of pyogenic meningitis or from septic emboli associated with endocarditis, lung abscess, or other serious purulent infections. Breaches of the blood–brain barrier (BBB) can result in CNS infections. Causes of such breaches include damage (e.g., microhemorrhage or necrosis of surrounding tissue) to the BBB; mechanical obstruction of microvessels by parasitized red blood cells, leukocytes, or platelets; overproduction of cytokines that degrade tight junction proteins; or microbe-specific interactions with the BBB that facilitate transcellular passage of the microorganism. The microorganisms that cause CNS infections include a wide range of bacteria, mycobacteria, yeasts, fungi, viruses, spirochaetes (e.g., neurosyphilis), and parasites (e.g., cerebral malaria and strongyloidiasis). The clinical picture of the various infections can be nonspecific or characterized by distinct, recognizable clinical syndromes. At some juncture, individuals with severe acute CNS infections require critical care management that warrants neuro-ICU admission. The implications for CNS infections are serious and complex and include the increased human and material resources necessary to manage very sick patients, the difficulties in triaging patients with vague or mild symptoms, and ascertaining the precise cause and degree of CNS involvement at the time of admission to the neuro-ICU. This chapter addresses a wide range of severe CNS infections that are better managed in the neuro-ICU. Topics covered include the medical epidemiology of the respective CNS infection; discussions of the relevant neuroanatomy and blood supply (essential for understanding the pathogenesis of CNS infections) and pathophysiology; symptoms and signs; diagnostic procedures, including essential neuroimaging studies; therapeutic options, including empirical therapy where indicated; and the perennial issue of the utility and effectiveness of steroid therapy for certain CNS infections. Finally, therapeutic options and alternatives are discussed, including the choices of antimicrobial agents best able to cross the BBB, supportive therapy, and prognosis.

Mimotope peptides selected from phage display combinatorial library by serum antibodies of pigs experimentally infected with Taenia solium as leads to developing diagnostic antigens for human neurocysticercosis

Neurocysticercosis is caused by penetration of the tapeworm Taenia solium larvae into the central nervous system resulting in a diverse range of neurologic complications including epilepsy in endemic areas that globalization spreads worldwide. Sensitive and specific immunodiagnosis is needed for the early detection and elimination of the parasite, but the lack of standardized, readily obtainable antigens is a challenge. Here, we used the phage display for resolving the problem. The rationale of the strategy rests on the concept that the screening of combinatorial libraries with polyclonal serum to pathogens reveals families of peptides mimicking the pathogen most immunodominant epitopes indispensable for the successful diagnosis. The screening of a 7mer library with serum IgG of four pigs experimentally infected with parasite followed by computer aided segregation of the selected sequences resulted in the discovery of four clusters of homologous sequences of which one presented a family of ten mimotopes selected by three infected pig serum IgGs; the common motif sequence LSPF carried by the family was considered to be the core of an immunodominant epitope of the parasite critical for the binding with the antibody that selected the mimotopes. The immunoassay testing permitted to select a mimotope whose synthetic peptide free of the phage with the amino acid sequence Leu-Ser-Fen-Pro-Ser-Val-Val that distinguished well a panel of 21 cerebrospinal fluids of neurocysticercosis patients from the fluids of individuals with neurological complications of other etiology. This peptide is proposed as a lead for developing a novel molecularly defined diagnostic antigen(s) for the neurocysticercosis.