Epidemiology of neurocysticercosis in Brazil

Neurocysticercosis: diagnosis via metagenomic next-generation sequencing

A 68-year-old Brazilian woman had 3 months of progressive fatigue, difficulty walking and 18 kg weight loss. On examination, there was gait apraxia and executive dysfunction. MR scan of brain showed communicating hydrocephalus and a cerebrospinal fluid showed 105 white cells/µL (≤5), predominantly lymphocytes, protein of 1.35 g/L (0.15-0.45) and the glucose content of 0.06 mmol/L (3.3-4.4). We suspected an infective cause and used of metagenomic next-generation sequencing to diagnose neurocysticercosis. This case highlights the challenge of diagnosing chronic meningitis and the relevance of genetic approaches in diagnosing neurological infections.

Diagnostic and therapeutic approach to chronic meningitis in Brazil: a narrative review

BACKGROUND

Chronic meningitis (CM) is characterized by neurological symptoms associated with the evidence of cerebrospinal fluid pleocytosis lasting > 4 weeks. Studies on the management of CM in Brazil are scarce.

OBJECTIVE

To critically review the literature on CM and propose a rational approach in the Brazilian scenario.

METHODS

Narrative literature review discussing the epidemiology, clinical evaluation, basic and advanced diagnostic testing, and empirical and targeted therapy for the most relevant causes of CM. The present review was contextualized with the local experience of the authors. In addition, we propose an algorithm for the management of CM in Brazil.

RESULTS

In Brazil, tuberculosis and cryptococcosis are endemic and should always be considered in CM patients. In addition to these diseases, neurosyphilis and other endemic conditions should be included in the differential diagnosis, including neurocysticercosis, Baggio-Yoshinari syndrome, and endemic mycosis. After infectious etiologies, meningeal carcinomatosis and autoimmune diseases should be considered. Unbiased and targeted methods should be used based on availability and clinical and epidemiological data.

CONCLUSION

We propose a rational approach to CM in Brazil, considering the epidemiological scenario, systematizing the etiological investigation, and evaluating the timely use of empirical therapies.

Genetic Diversity of Taenia solium and its Relation to Clinical Presentation of Cysticercosis

In this perspectives paper, we discuss fertilization strategies for Taenia saginata and Taenia saginata asiatica as well as heterogeneity in Taenia solium, the causative agent of human cysticercosis. Two different genotypes of T. solium (Asian and Afro/American) were confirmed by mitochondrial DNA analysis approximately two decades ago. Since then, outcrossings of the two genotypes have been identified in Madagascar where the two genotypes are distributed sympatrically. Outcrossings were confirmed by the presence of discordance between mitochondrial and nuclear DNA. Since multiple tapeworm infections are common in endemic areas, outcrossing events likely occur quite frequently. Therefore, mitochondrial DNA from T. solium specimens collected from humans and pigs in endemic areas should be analyzed. If variations are found between specimens, nuclear DNA analysis should be performed to confirm the presence of discordance between mitochondrial and nuclear genes. Additional outcrossings likely add complexity to understanding the existing genetic diversity. Serological surveys are also recommended since serodiagnostic glycoprotein can also differentiate between the two genotypes. Viable eggs from different genotypes or from hybrids of two different genotypes should be used for experimental infection of pigs or dogs in order to observe any pathological heterogeneity in cysticercosis development. Although genetic diversity of T. solium is expected to result in clinical heterogeneity of cysticercosis in humans and pigs, there is currently no evidence showing that this occurs. There are also no comparative experimental studies on this topic. Therefore, studies evaluating the link between parasite heterogeneity and clinical outcome are warranted.

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.

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.

Neuroimaging observations linking neurocysticercosis and mesial temporal lobe epilepsy with hippocampal sclerosis

OBJECTIVE

To test if chronic calcificed neurocysticercosis (cNCC) and hippocampal sclerosis occur more often than by chance ipsilateral to the same brain hemisphere or brain region in mesial temporal lobe epilepsy associated with hippocampal sclerosis (MTLE-HS) plus neurocysticercosis. This proof-of-concept would provide important evidence of a direct pathogenic relationship between neurocysticercosis and MTLE-HS.

METHODS

A cohort of 290 consecutive MTLE-HS surgical patients was studied. A test of proportions was used to analyze if the proportion of patients with a single cNCC lesion matching the same brain hemisphere or region of hippocampal sclerosis was significantly greater than 50%, as expected by the chance.

RESULTS

Neuroimaging findings of cNCC were observed in 112 (38.6%) of 290 MTLE-HS patients and a single cNCC lesion occurred in 58 (51.8%) of them. There were no differences in main basal clinical characteristics of MTLE-HS patients with single or multiple cNCC lesions. In patients with single cNCC lesions, the lesion matched the side in which hippocampal sclerosis was observed in 43 (74.1%) patients, a proportion significantly greater than that expected to occur by chance (p=0.008). Neurocysticercosis in temporal lobe was ipsilateral to hippocampal sclerosis in 85.0% of patients and accounted mostly for this result.

CONCLUSIONS

This work is a proof-of-concept that the association of neurocysticercosis and MTLE-HS cannot be explained exclusively by patients sharing common biological or socio-economic predisposing variables. Instead, our results suggest the involvement of more direct pathogenic mechanisms like regional inflammation, repetitive seizures or both. Neurocysticercosis within temporal lobes was particularly related with ipsilateral hippocampal sclerosis in MTLE-HS, a finding adding new contributions for understanding MTLE-HS plus cNCC or perhaps to other forms of dual pathology in MTLE-HS.

A rapid slide agglutination test for the diagnosis of neurocysticercosis in the rural health set up

Background:

Simple and rapid latex-based diagnostic tests have been used for detecting specific antigens or antibodies in several diseases.

Aims:

The aim of the present study was to standardize and evaluate the latex agglutination test (LAT) for the detection of Taenia solium metacestode antigen in the cerebrospinal fluid (CSF) and serum for the diagnosis of neurocysticercosis (NCC).

Settings and Design:

The study was conducted at Department of Microbiology, Jawaharlal Institute of Post graduate medical education and research after obtaining informed consent from the study subjects.

Materials and Methods:

In the present study, CSF and serum samples were collected from clinically suspected NCC, CT/MRI proven cases of NCC, non-cysticercal central nervous system infection control and from healthy control subjects. CSF was not collected from healthy controls. Polyclonal antisera raised in rabbits against porcine T. solium metacestode complete homogenate antigen, was used in the LAT to detect the antigen in the specimens.

Statistical Analysis Used:

The statistical analysis was carried out using Epi Info. The sensitivity, specificity, positive predictive value, and negative predictive value of the LAT were calculated.

Results:

The LAT exhibited sensitivity of 64.7% and specificity of 85.7% with CSF samples and sensitivity of 52.08% and specificity of 96% with serum samples.

Conclusions:

Results of the present study shows that the LAT can be employed as a moderately sensitive and specific test for the detection of T. solium metacestode antigen in the CSF and serum specimens for the diagnosis of NCC in poorly equipped laboratories.

Cognitive and surgical outcome in mesial temporal lobe epilepsy associated with hippocampal sclerosis plus neurocysticercosis: a cohort study

Background

Where neurocysticercosis (NCC) is endemic, chronic calcified neurocysticercosis (cNCC) can be observed in patients with mesial temporal lobe epilepsy associated with hippocampal sclerosis (MTLE-HS). Considering that both disorders cause recurrent seizures or cognitive impairment, we evaluated if temporal lobectomy is cognitively safe and effective for seizure control in MTLE-HS plus cNCC.

Methods

Retrospective cohort study of neuropsychological profile and surgical outcome of 324 MTLE-HS patients submitted to temporal lobectomy, comparing the results according to the presence or absence of cNCC.

Findings

cNCC occurred in 126 (38.9%) of our MTLE-HS patients, a frequency higher than expected, more frequently in women than in men (O.R. = 1.66; 95% C.I. = 1.05–2.61; p = 0.03). Left-side (but not right side) surgery caused impairment in selected neuropsychological tests, but this impairment was not accentuated by the presence of cNCC. Ninety-four (74.6%) patients with MTLE-HS plus cNCC and 153 patients (77.3%) with MTLE-HS alone were Engel class I after surgery (O.R. = 1.16; 95% C.I. = 0.69–1.95; p = 0.58). However, the chances of Engel class IA were significantly lower in MTLE-HS plus cNCC than in patients with MTLE-HS alone (31.7% versus 48.5%; O.R. = 2.02; 95% C.I. = 1.27–3.23; p = 0.003). Patients with MTLE-HS plus cNCC showed higher rates of Engel class ID (15.1% versus 6.6%; O.R. = 2.50; 95% C.I. = 1.20–5.32; p = 0.012).

Interpretation

cNCC can be highly prevalent among MTLE-HS patients living in areas where neurocysticercosis is endemic, suggesting a cause-effect relationship between the two diseases. cNCC does not add further risk for cognitive decline after surgery in MTLE-HS patients. The rates of Engel class I outcome were very similar for the two groups; however, MTLE-HS plus cNCC patients achieved Engel IA status less frequently, and Engel ID status more frequently. Temporal lobectomy can be safely performed in most patients with MTLE-HS plus cNCC without affecting cognitive outcome. Long-term surgical seizure control in MTLE-HS plus cNCC is still satisfactory, as long as selected patients remain under medication.

The association of living conditions and lifestyle factors with burden of cysts among neurocysticercosis patients in Ecuador

We used baseline data on 154 symptomatic neurocysticercosis (NCC) patients in Ecuador to identify predictors of the burden of cysts. We ran logistic regression models with the burden of cysts as the outcome, defined as the number of cysts in the brain (1 vs >1), and having cysts in all 3 phases of evolution (active, transitional and calcifications) vs <3. These two outcomes are thought to be indicators of exposure dose and/or repeated exposure over time. The predictors examined were: living in a rural area, living on a dirt road, living in an adobe or wood house (vs brick/cement), no running water in the house, no bathroom in the house, having a domestic employee cook in the home, eating most meals at restaurants or street vendors, working in a manual labour job. We found that the odds of having multiple NCC cysts was higher among those working in manual labour (OR=3.5, p=0.004), and those who ate most meals outside the home had higher odds of having cysts in all 3 phases (OR=5.0, p=0.007). Burden of cysts may be a useful outcome when looking to identify exposure risk factors in the absence of an uninfected control group.

Neurocisticercose nodular calcificada com sinais de reativação

A neurocisticercose é uma doença caracterizada pelo envolvimento do sistema nervoso central pelo estágio larval intermediário do parasita Taenia solium. O processo de degeneração da larva e a reação inflamatória do organismo causam os sintomas clínicos. Relatamos a reativação clínica e radiológica de uma forma nodular calcificada e assintomática há mais de 20 anos. O tratamento antiparasitário mostrou boa resposta.

Caracterização das lesões por Cysticercus bovis, na inspeção post mortem de bovinos, pelos exames macroscópico, histopatológico e pela reação em cadeia da polimerase (PCR)

Considerando a necessidade do conhecimento da cisticercose bovina e do aperfeiçoamento dos métodos de diagnóstico desta doença, objetivou-se verificar a ocorrência do Cysticercus bovis nos diversos locais anatômicos, tais como: cabeça, coração, esôfago, diafragma, língua, fígado e carcaça, examinados pelo Serviço de Inspeção Federal. O diagnóstico foi feito por macroscopia, microscopia e PCR com extração de DNA por fervura para a identificação do metacestóide. Dos 22043 bovinos abatidos, 713 (3,23%) estavam infectados. O coração foi o sítio anatômico mais afetado, com 1,90% (420/22043), seguido da cabeça, 1,11% (245/22043), do esôfago, 0,08% (18/22043), da carcaça, 0,07% (15/22043), do diafragma, 0,03% (7/22043), do fígado, 0,02% (5/22043) e da língua, 0,01% (3/22043). Dos cistos obtidos, 58,35% (416/713) estavam mortos e 41,65% (297/713), vivos. As diferenças entre os sítios anatômicos e a condição morfológica dos cistos foram significativas (p < 0,05). Dos 416 cistos mortos, 253 foram examinados por apresentarem características de: lesões nodulares firmes, brancacentas, com material amarelado, por vezes com aspecto calcário, no interior. O exame microscópico revelou granulomas comumente representados por centro necrótico e/ou mineralizado, envolto por histiócitos dispostos em paliçada, células gigantes multinucleadas, infiltrado misto, predominantemente de mononucleares, e fibrose. Por vezes, a periferia das lesões tinha características de tecido de granulação e mineralização em forma de lâminas lineares. Os restos parasitários foram identificados como um material hialino acelular, contendo elementos ovais e circulares, basofílicos, acidófilos e incolores, denominados corpúsculos calcários. Em algumas lesões foram observados raros corpúsculos, dispersos na reação inflamatória. Nódulos fibrosos, ricos em infiltrado linfóide ou crônico ativos, foram frequentemente visualizados. Dos cistos vivos examinados, 65% (13/20) foram positivos para C. bovis , confirmando o diagnóstico ambulatorial e a eficácia do método de PCR utilizado. Em virtude da positividade observada para C. bovis nos exames histopatológico e PCR, particularmente em fígado e esôfago, sugere-se que seja reformulado o artigo 176 do Regulamento de Inspeção Industrial e Sanitária de Produtos de Origem Animal, incluindo estes locais na rotina de inspeção nos matadouros.

Neurocysticercosis--retrospective study of autopsy reports, a 17-year experience

Neurocysticercosis (NCC) is a common central nervous system (CNS) infection caused by Taenia solium metacestodes. The objective of this study is to describe the incidence of cysticercosis diagnosed at autopsies and describe the epidemiological and clinical characteristics of NCC. Retrospective study analyzing 6,500 reports of autopsies between 1977 and 1994 from a school hospital in Curitiba, PR, southern of Brazil. The following data was obtained, age, gender, site of cysticercosis, NCC as cause of death. The diagnosis of cysticercosis was established in 52 (0.8%) autopsies. From 1977 to 1987 (0.7%) and from 1988 to 1994 (1.1%). In the autopsies with cysticercosis 75% were male; age (mean ± SD) was 43 ± 20. NCC was present in 96% of cases, and seizures was the most frequent clinical manifestation. Asymptomatic cases in 54%. These data classify our area as hiperendemic, according with OMS criteria. The present study reinforces the necessity to develop adequate control programs.

Neurocysticercosis in travelers: a nation-wide study in Israel

BACKGROUND

Cysticercosis, a human infestation by Taenia solium is endemic in many resource-limited countries. In developed countries it is mostly encountered among immigrant populations. Only few cases are reported in travelers. This report summarizes a nation-wide study of neurocysticercosis (NCC) diagnosed among Israeli travelers to endemic countries, with an estimation of disease incidence among the traveler population.

METHODS

We performed a retrospective, nation-wide survey of travel-related NCC in Israel between the years 1994 and 2009.

RESULTS

Nine cases of NCC were diagnosed in Israeli travelers during the study years. Most patients had traveled to South and/or Southeast Asia. The most common symptom at diagnosis was a seizure. The average interval between return from the suspected travel and symptom onset was 3.2 ± 1.8 years. Two patients suffered from multiple lesions, whereas the rest had a single lesion. Antihelminthic treatment was given to most patients with resolution of symptoms. Median duration of antiepileptic treatment was 16 ± 41 months after albendazole was given. Antiepileptic treatment was discontinued without any complications. The estimated attack rate of clinical disease was 1 : 275,000 per travel episode to an endemic region.

CONCLUSIONS

NCC in travelers is a rare phenomenon commonly presenting as seizure disorder manifesting months to years post-travel. Antihelminthic therapy followed by 12 to 24 months of antiepileptic therapy resulted in complete resolution of symptoms in our patients.

Neurocysticercosis: relationship between Taenia antigen levels in CSF and MRI

OBJECTIVE

To determine the relationship between Taenia antigen (TA) detection in cerebrospinal fluid (CSF) and magnetic resonance imaging (MRI) findings in patients with definite diagnosis of neurocysticercosis (NC).

METHOD

Sixty-three patients with definite diagnosis of NC were submitted to a MRI of the brain, and to a CSF examination, with a meticulous search for TA by ELISA.

RESULTS

TA detection was positive in 36 patients (57.1%). A total of 836 lesions were analyzed, greatly within the cerebral parenchyma (98.7 of the lesions). Intact or non-degenerating cysts were the most common evolutive phase observed (50.4% of all lesions), 22.1% were degenerating cysts and 19.5% calcified cysts. We observed a significant relationship between TA levels detected and the total number of lesions and the number of non-degenerating cysts, but not with calcified lesions.

CONCLUSION

According to our results, we propose at least four important types of contribution: (1) TA detection may allow etiologic diagnosis in transitional phases of NC, with non-characteristic images; (2) in final stages of evolution of cysticercoids in the CNS, lesions may not appear on CT or MRI, and TA detection may contribute to a definite etiologic diagnosis; (3) TA detection may permit diagnosis of NC in some patients with previous negative tests for antibody detection in CSF; (4) TA detection may represent an accurate marker of disease activity in the epileptic form of NC.

Detection of Taenia solium antigens and anti-T. solium antibodies in paired serum and cerebrospinal fluid samples from patients with intraparenchymal or extraparenchymal neurocysticercosis

BACKGROUND

Neurocysticercosis (NCC) is a frequent cause of epilepsy worldwide. Compared with the more common parenchymal brain cysts, extraparenchymal infections are difficult to manage and have a poor prognosis. Serological assays are used to detect circulating Taenia solium antigens or anti-T. solium antibodies in serum or cerebrospinal fluid (CSF) samples. There are no guidelines on whether to use serum or CSF specimens for a particular assay.

METHODS

We obtained paired serum and CSF samples from 91 patients with NCC (48 had intraparenchymal NCC, and 43 had extraparenchymal NCC) for detection of antibodies, using an enzyme-linked immunotransfer blot (EITB) assay, and antigens, using a monoclonal antibody-based enzyme-linked immunosorbent assay (ELISA).

RESULTS

For the intraparenchymal NCC group, the EITB assay yielded more true-positive results for serum samples, and the ELISA yielded slightly more true-positive results for CSF samples than for serum samples, but none of these differences were statistically significant. Most patients with calcified NCC were antibody positive but antigen negative. For extraparenchymal disease, all samples were antibody positive, and all but 2 were antigen positive, with most samples containing high antigen levels.

CONCLUSIONS

The sensitivity of antibody-detecting EITB assays is not increased through the use of CSF samples rather than serum samples. The antigen-detecting ELISA performed better for CSF samples than for serum samples, but for both specimen types it was less sensitive than the EITB assay. Active and inactive NCC are better differentiated from each other by the antigen-detecting ELISA, for both serum and CSF samples. High antigen levels suggest the presence of subarachnoid NCC.

Anatomopathological aspects of neurocysticercosis in autopsied patients

The aim of this paper was to describe the occurrence and morphology of neurocysticercosis (NCC) in autopsies. We revised 2218 autopsies performed at the School Hospital from Federal University of Triangulo Mineiro, 1970-2003. Data referring to age, gender and color of patients were reported and NCC was microscopically and macroscopically analyzed. We found 53 (2.4%) NCC cases. The mean age was 50 years old, 34 (64.1%) individuals were male and 36 (67.9%) white. Macroscopically, 17 cysticerci were analyzed. The most frequent location was meningocortical in 12 (70.6%) cases. Microscopically, the cysticerci presented an ovoid shape, containing the larvae preserved in 4 (23.5%) cases or in destruction degrees in 13 (76.5%) cases. Therefore, in NCC was found several general pathologic processes (necrosis, interstitial deposits, fibrosis, gliosis, inflammation) amongst which are highlighted beta-fibrillose in 13 (76.5%) cases associated to inflammatory process in 16 (94.1%) cases caused by the parasite, not yet related to NCC, and calcification present in viable and destruction parasites.

Evaluation of Taenia solium and Taenia crassiceps cysticercal antigens for immunodiagnosis of neurocysticercosis using ELISA on cerebrospinal fluid samples

The efficacy of whole parasite and vesicular fluid antigen extracts from Taenia solium and Taenia crassiceps cysticerci for immunodiagnosis of neurocysticercosis was evaluated using ELISA on cerebrospinal fluid samples. Anticysticercal IgG antibodies were assayed in cerebrospinal fluid samples from 23 patients with neurocysticercosis and 35 patients with other neurological disorders. The ELISA reaction for the whole Taenia solium cysticercal extract showed 91.3% sensitivity and 94.3% specificity, whereas the sensitivity and specificity of the ELISA for the whole Taenia crassiceps cysticercal extract were 87% and 94.3%, respectively. The ELISA reactions for vesicular fluid from Taenia solium or Taenia crassiceps showed 91.3% sensitivity and 97.1% specificity. Considering the results obtained from the four antigen preparations, vesicular fluid from Taenia solium and Taenia crassiceps cysticerci may be useful as a source of antigens for immunological reactions that are used for detecting specific antibodies in cerebrospinal fluid samples from patients with neurocysticercosis.

Recombinant expression of Taenia solium TS14 antigen and its utilization for immunodiagnosis of neurocysticercosis

In order to evaluate the potential use of TS14 antigen in an enzyme-linked immunosorbent assay (ELISA) for immunodiagnosis of neurocysticercosis (NC), its open reading frame (ORF) was amplified by RT-PCR from mRNA isolated from Taenia solium cysticerci. The ORF was subcloned into the expression vector pET-28a, and was used to transform Escherichia coli BL21 (DE3) cells to produce TS14 antigen. The His-tagged expressed protein was purified on a nickel affinity column. Using the HISTS14 as antigen, ELISA was positive for 100% of cerebrospinal fluid (CSF) and 97% of serum samples from NC patients. No positive results were observed with sera and CSF samples from control groups. Cross-reactivity with sera from patients with schistosomiasis and Chagas' disease was not observed. Serum samples from patients with taeniasis were evaluated and 2 of 13 cases showed reactivity in this assay. Our data indicate the usefulness of HISTS14 in ELISA for an accurate and rapid assay for diagnosis of NC and seroepidemiological studies.

[Neurocysticercosis in a State of Piauí urban area: case report]

Neurocysticercosis is a serious public health problem that predominantly affects places with poor sanitary and hygiene conditions. The Piaui State is out of the neurocysticercosis map in Brazil but, as this study illustrates, it is just by lack of epidemiologic data. We demonstrate the presence of this pathology in the State of Piaui based on a case report of a 39 years old man, followed for 17 months. The diagnosis was made by CT scan and the patient was treated with albendazol for 10 days. A new CT scan show absence of lesions. He needed to be treated again after a recurrence of clinical manifestations, 6 months after the first treatment, with the disappearance of the new lesions.

Neurocysticercosis and microscopic hippocampal dysplasia in a patient with refractory mesial temporal lobe epilepsy

Epidemiologic studies suggest that neurocysticercosis (NC) is the main cause of symptomatic epilepsy in developing countries. The association between NC and mesial temporal lobe epilepsy (MTLE) has been reported by several authors. Recent data have shown that the presence of NC does not influence the clinical and pathological profile in MTLE patients and suggest that not all cysticercotic lesions are inevitably epileptogenic. We describe a 50-years-old woman with partial seizures due to NC which evolve to MTLE. The patient was submitted to a corticoamygdalohippocampectomy to treat refractory epilepsy. An immunohistochemical study using neuronal markers was made on hippocampal formation. Besides the typical aspects of Ammon's horn sclerosis (AHS), the microscopic examination demonstrates cellular features of hippocampal malformation including dysmorphic neurons and focal bilamination of granular cell layer. We suggest that, in this case, a developmental disorder lowered the threshold for the NC-induced seizures and contributed to the establishment of refractory epilepsy.

Cerebral mass in a 13-year-old girl following long-term sojourn in the Tropics

Cysticercosis of the central nervous system is the main cause of late-onset epilepsy in tropical countries. The case of a 13-year-old German girl with a generalized seizure following long-term sojourns in the Tropics is reported. Cranial imaging showed two cerebral lesions with central calcifications. Serological, molecular and cultural examination of cerebrospinal fluid and blood was negative for various parasites, fungi and bacteria including mycobacteria. Histopathological examination after neurosurgical resection revealed calcareous bodies pathognomonic for platyhelminths, in particular tapeworms. Taken together, the radiological and histopathological findings indicate infection with cysticerci, the larvae of Taenia solium.

Serum and cerebrospinal fluid S100B concentrations in patients with neurocysticercosis

The clinical manifestations of neurocysticercosis (NC) are varied and depend on the number and location of cysts, as well as on the host immune response. Symptoms usually occur in NC when cysticerci enter a degenerative course associated with an inflammatory response. The expression of brain damage markers may be expected to increase during this phase. S100B is a calcium-binding protein produced and released predominantly by astrocytes that has been used as a marker of reactive gliosis and astrocytic death in many pathological conditions. The aim of the present study was to investigate the levels of S100B in patients in different phases of NC evolution. Cerebrospinal fluid and serum S100B concentrations were measured in 25 patients with NC: 14 patients with degenerative cysts (D), 8 patients with viable cysts (V) and 3 patients with inactive cysts. All NC patients, except 1, had five or less cysts. In most of them, symptoms had been present for at least 1 month before sample collection. Samples from 8 normal controls (C) were also assayed. The albumin quotient was used to estimate the blood-brain barrier permeability. There were no significant differences in serum (P = 0.5) or cerebrospinal fluid (P = 0.91) S100B levels among the V, D, and C groups. These findings suggest that parenchymal changes associated with a relatively small number of degenerating cysts probably have a negligible impact on glial tissue.

Intrathecal synthesis of specific immunoglobulin G antibodies in neurocysticercosis: evaluation of antibody concentrations by enzyme-linked immunosorbent assay using a whole cysticercal extract and cyst vesicular fluid as antigens

The demonstration of intrathecal antibody production has proven useful for showing the involvement of the central nervous system (CNS) in several diseases. In the present study, the intrathecal synthesis of cysticercus-specific immunoglobulin G (IgG) antibodies was investigated in 30 patients with neurocysticercosis based on calculation of the specific IgG antibody index (AI(IgG)). An AI(IgG) > or =1.5 was considered to be indicative of intrathecal antibody production. Antibody concentrations in serum and cerebrospinal fluid samples were evaluated using an enzyme-linked immunosorbent assay with 2 antigen preparations from Taenia solium cysticerci, namely, a whole cysticercal extract (TsoW) and the vesicular fluid of the parasite (TsoVF). Intrathecal, cysticercus-specific IgG antibody synthesis was observed in 21 (70%) and 23 (76.6%) patients using the TsoW and TsoVF antigens, respectively. The detection of the intrathecal synthesis of specific antibodies may be a potentially useful tool in establishing the involvement of CNS in cysticercosis.

Evaluation of Taenia solium and Taenia crassiceps cysticercal antigens for the serodiagnosis of neurocysticercosis

We evaluated the usefulness of seven cysticercal antigen extracts, four from Taenia solium cysticerci (whole parasite-TsoW, membrane-TsoMe, vesicular fluid-TsoVF and scolex-TsoSc) and three from T. crassiceps cysticerci (whole parasite-TcraW, membrane-TcraMe and vesicular fluid-TcraVF), for serodiagnosis of neurocysticercosis with an enzyme-linked immunosorbent assay (ELISA). Cysticercus-specific IgG were screened in serum samples from 23 patients with neurocysticercosis, 32 patients with other infections and 48 healthy persons. The best results were obtained with the TsoVF-ELISA (91.3% sensitivity; 96.2% specificity) and TcraVF-ELISA (91.3% sensitivity; 95% specificity). The ELISA done with whole parasite and membrane extracts from cysts of T. solium and T. crassiceps and the scolex extract from T. solium cysts showed a low performance in terms of sensitivity, ranging from 47.8% to 73.9%. None of the antigen preparations from T. solium and T. crassiceps cysticerci used in this study showed outstanding performance for the serodiagnosis of neurocysticercosis. However, considering the results obtained with the seven antigen preparations, vesicular fluid from T. solium and T. crassiceps cysticerci may be useful for detecting specific antibodies in sera from patients with neurocysticercosis.

Parkinsonism associated with neurocysticercosis

We report two cases of brainstem cysticercotic ependymitis presenting with rigid-akinetic syndrome. There was a good response to levodopa therapy as well as cysticidal therapy with albendazole, allowing later reduction of levodopa dosage in one patient and complete withdrawal in the other.

Estudo soroepidemiológico da cisticercose humana em um município do Estado do Piauí, Região Nordeste do Brasil

Integrando as pesquisas sobre parasitoses na região do entorno do Parque Nacional Serra da Capivara, Piauí, Brasil, realizadas entre 1999 e 2001, o presente estudo tem como objetivo avaliar a situação epidemiológica da cisticercose humana no Município de João Costa, no Nordeste do Brasil. Foram obtidas informações clínico-epidemiológicas e coletadas amostras de sangue para testes sorológicos imunoenzimáticos (ELISA e Western blot), empregando cisticercos de Taenia crassiceps como antígeno. Na primeira etapa, em 1999, foram investigadas 169 pessoas com história confirmada ou suspeita de infecção/doença pelo complexo teníase-cisticercose, e seus familiares. Na análise, 13,6% das pessoas apresentaram soros reagentes para cisticercose pelo método ELISA. Na segunda etapa, em 2001, foram avaliadas 92 amostras de soro de indivíduos reativos para cisticercose detectados no primeiro momento e seus familiares, sendo que 24,0% das amostras de soro foram reagentes para cisticercose pelo ELISA, e 29,0%, pelo WB. Nessa mesma etapa, realizou-se inquérito coprológico em 701 pessoas, incluindo voluntários. A prevalência de parasitoses intestinais foi de 51,0%, tendo sido observada uma maior prevalência de protozoários (95,0%) em relação aos helmintos (5,0%). Os resultados do estudo indicam o caráter endêmico da cisticercose na área, além da elevada freqüência de protozooses intestinais.

Effect of Cysticercus cellulosae on neutrophil function and death

Neutrophils, eosinophils and macrophages interact with invading parasites and naive hosts. The initial reaction of leukocytes is the generation of reactive oxygen species (ROS). The cytotoxic effects of extracts derived from intact Cysticercus cellulosae and from the scolex or membrane fractions on neutrophils were examined. DNA fragmentation of neutrophils was observed when cells were incubated with an extract from the intact metacestode; however, the addition of antioxidant enzymes to the incubation medium had a protective effect. The scolex and membrane extracts did not affect DNA fragmentation of neutrophils. Hydrogen peroxide production of neutrophils incubated with metacestode fractions from C. cellulosae increased by 190% (total extract), 120% (scolex) or 44% (membrane). An increase in antioxidant catalase activity (28%) concomitant with the increased production of ROS was observed in neutrophils incubated with metacestode fractions, which could be an attempt at self-protection. ROS production by neutrophils in the presence of the intact cysticerci extract did not alter phagocytosis. In contrast, the scolex and membrane fractions increased the phagocytic capacity of neutrophils by 44 and 28%, respectively. The results showed that the extract from intact C. cellulosae was toxic for neutrophils via ROS production, leading to DNA fragmentation and inhibition of phagocytic capacity, but neutrophils are able to protect themselves against oxidative stress by via catalase activity.

Neuron-specific enolase in patients with neurocysticercosis

BACKGROUND

Neurocysticercosis (NC) is the most frequent parasitic disease of the human nervous system. Its clinical manifestations are varied and depend on the number and location of cysts, as well as the host immune response. Symptoms in NC usually occur when cysts enter into a degenerative phase associated with perilesional inflammation. We speculate that neuron-specific enolase (NSE)--a marker of neuronal injury--could be elevated in patients with degenerating cysts comparing to those with viable cysts.

METHODS

We examined serum NSE (sNSE) and cerebrospinal fluid (CSF) NSE (cNSE) levels in 25 patients with NC: 14 patients with degenerative cysts (D), 8 patients with viable cysts (V) and 3 patients with inactive cysts. Samples of eight normal controls (C) were also obtained. Determination of albumin was performed in serum and CSF samples, and the CSF/serum albumin ratio (albumin quotient, Q(alb)) was used to estimate the blood-brain barrier permeability.

RESULTS

All patients, with the exception of one case, had five or less cysts. Comparisons between V, D and C groups did not demonstrate significant differences of cNSE, Q(alb) and sNSE levels. Further, there were no significant differences of cNSE and sNSE levels between patients with or without intracranial hypertension (ICH).

CONCLUSIONS

These findings suggest that the inflammatory response associated with a relatively small number of degenerating cysts does not provoke significant neuronal damage. Further studies considering patients with a larger number of cysts will be required to assess if there is evidence of neuronal damage in such more severe cases.

Helminth antigens (Taenia solium, Taenia crassiceps, Toxocara canis, Schistosoma mansoni and Echinococcus granulosus) and cross-reactivities in human infections and immunized animals

Helminth antigens were investigated in the search for accessible heterologous antigens capable to discriminate different helminthiases, by the enzyme linked immunosorbent assay (ELISA) and the immunoblot assay (IB). Antigens used were: Taenia solium cysticercus total saline (Tso); Taenia crassiceps cysticercus vesicular fluid (Tcra-VF); T. crassiceps cysticercus glycoproteins (Tcra-GP and Tcra-(18-14)-GP); Toxocara canis larva excretory-secretory (TES); Schistosoma mansoni adult total saline (Sm) and Echinococcus granulosus hydatid fluid (Eg). The assayed sera were from patients with: cysticercosis (n = 18); toxocariasis (n = 40); schistosomiasis (n = 19) and hydatidosis (n = 50) with proven clinical and laboratory diagnosis, and sera from rabbits immunized with Tso, Tcra-VF, TES and Eg. Cross-reactivity occurred mostly between infections caused by Taenia and Echinococcus or in immunized rabbits, by ELISA. Moreover, the cross-reactivity among helminthiases was found with the use of antigens belonging to phylogenetically related parasite species, Eg, Tso and Tcra-VF, by sharing same antigenic components. Lower cross-reactivities were obtained by IB technique, when only peptides were considered as antigens, and the use of T. crassiceps purified glycoproteins demonstrated high sensitivity and specificity in the diagnosis of human cysticercosis, similarly to that using homologous antigen (Tso) by the same technique.

Aspectos clínico-epidemiológicos da neurocisticercose no Brasil: análise crítica

Com o objetivo de mostrar as características da neurocisticercose (NCC) no Brasil, realizou-se análise critica da literatura nacional que mostrou incidência de 1,5% nas necropsias e de 3,0% nos estudos clínicos, correspondendo a 0,3% das admissões em hospitais gerais. Em estudos soroepidemiológicos, a positividade para cisticercose foi de 2,3%. O paciente brasileiro com NCC pode apresentar um perfil clínico-epidemiológico geral (homem, 31-50 anos, procedência rural, manifestações epilépticas parciais complexas, LCR normal ou hiperproteinorraquia, calcificações ao exame de TC, constituindo a expressão da forma inativa da NCC) e outro de gravidade (mulher, 21-40 anos, procedência urbana, manifestações de cefaléia vascular e HIC, típica síndrome do LCR ou alteração de dois ou mais parâmetros, vesículas associadas ou não a calcificações ao exame de TC, constituindo a expressão da forma ativa da NCC). Os coeficientes de prevalência nacionais são muito subestimados, embora em duas cidades do interior de São Paulo tenham sido verificados os valores de 72:100.000 e 96:100.000/habitantes. Discutem-se aspectos relacionados à subestimação da prevalência desta neuroparasitose no Brasil.

Endoscopic approach to fourth ventricle cysticercosis

Neurocysticercosis is the most frequently observed parasitosis of the central nervous system worldwide. The fourth ventricle is the most frequent site of intraventricular infestation, a location that carries a higher risk for CSF blockage and intracranial hypertension due to CSF blockage. A great number of patients become shunt dependent which carries a poorer prognosis. We report on a case of a patient with symptomatic obstructive hydrocephalus due to cysticercus in the fourth ventricle where an endoscopic approach via a frontal burr hole was performed. Although there is no consensus in the literature for the optimal treatment of this disease, this method seemed adequate for treatment of fourth ventricle cysticercosis in patients with hydrocephalus, aqueductal and foramen of Monro dilatations.

Características evolutivas do Cysticercus cellulosae no encéfalo e no coração humanos

O presente estudo teve como objetivos avaliar a prevalência de cisticercose, classificar as etapas evolutivas dos cisticercos encontrados nos encéfalos e corações humanos, diferenciá-las de acordo com os aspectos macro e microscópicos dos processos patológicos gerais e comparar os processos encontrados nos encéfalos e corações. Foram revisados protocolos de autópsias realizadas no Hospital Escola da Faculdade de Medicina do Triângulo Mineiro, Uberaba, MG, Brasil, no período de 1970 a 2000. Verificou-se a prevalência da cisticercose em 71 casos, sendo 18 (25,4%) de cisticercose cardíaca e 53 (74,6%) de encefálica. Foram analisados 19 cisticercos, sendo 9 de encéfalos e 10 de corações. Os cisticercos foram classificados, de acordo com sua fase evolutiva, em etapas: vesicular, vesicular coloidal, granular nodular e nodular calcificada, com similaridade entre os diagnósticos macro e microscópico. Entre os processos patológicos destacaram-se a beta-fibrilose e a fibroelastose endocárdica. Adicionalmente, demonstrou-se que a classificação pode ser aplicada tanto na cisticercose encefálica como na cardíaca.

Anti-Taenia solium metacestodes antibodies in serum from blood donors from four cities of Triângulo Mineiro area, Minas Gerais, Brazil, 1995

Serological survey was performed to detect IgG antibodies anti-Taenia solium metacestodes in blood donors of Hemocentro Regional de Uberlândia, Minas Gerais, Brazil. A total of 1133 sera from blood donors coming from four cities of Triângulo Mineiro area were analyzed by the indirect fluorescence antibody test (IFAT) and the enzyme linked immunosorbent assay (ELISA). Specific IgG antibodies were found in 5.6% of the studied population, showing differences in the positive rates according to their origin: Araguari (13.5%), Tupaciguara (5.0%), Monte Alegre de Minas (4.8%) and Uberlândia (4.7%). The results indicate the probable endemicity of cysticercosis in this population.

Surgical treatment of cerebral cysticercosis: long-term results and prognostic factors

Object

Cysticercosis is the most frequent parasitosis of the central nervous system. Although anticysticercal drugs have proven efficient in some cases, many patients with NCC require palliative, occasionally curative, surgical procedures. The authors analyzed the data and prognostic factors obtained during the follow-up period (range 1–255 months, median 38 months) in 160 patients with cerebral cysticercosis who underwent surgical treatment.

Methods

Different surgical approaches were indicated to control increased intracranial pressure (ICP) in most patients, and some patients had undergone decompressive surgery for local brain lesions. Most patients required more than one surgical procedure. Statistical analysis was performed using the Fisher exact, the log-rank, and the Kruskall–Wallis tests. Survival curves were calculated according the Kaplan–Meier method. The removal of a giant cyst from the parenchyma or cisterns for relief of increased ICP and for chiasm/optic nerve decompression improved most symptoms in patients. The removal of ventricular cysts was effective in the control of increased ICP in most patients. Patients with a ventricular cyst and ependymitis/arachnoiditis required placement of a ventriculoperitoneal (VP) shunt after the cyst was removed. This therapy effectively controlled increased ICP. Patients younger than 40 years of age at the time of treatment and male patients had worse outcomes. The outcome in patients who underwent VP shunt surgery or shunt surgery combined with reservoir implantation was worse than that in those who underwent cyst removal alone. Shunt-related infection was the most frequent complication, and the global mortality rate during the follow-up period was 21.2%. Although both complications were more frequent in the first 2 postoperative years, they occurred at any time.

Conclusions

Long-term prognosis in patients with cerebral cysticercosis who required surgery was not good. Cysts located in the basal cisterns and patient age younger than 40 years were poor prognostic factors.

Taeniasis and cysticercosis prevalence in a small village from Northeastern Brazil

Although not considered as an endemic region, the Northeast of Brazil has the necessary conditions for the development of taeniasis-cysticercosis complex. In a previous paper, we demonstrated that Mulungu do Morro municipality, in the State of Bahia, has a high seroprevalence to cysticercosis in epileptic patients.

OBJECTIVE

to determine the prevalence of taeniasis and positive cysticercosis serology in the population of Mulungu do Morro.

METHOD

blood and stool samples were collected from a random sampling of the population, by family. The identification of antibodies against T. solium cysticerci was made by EITB and T. solium antigens were identified using a polyclonal antibody-capture ELISA.

RESULTS

the cysticercosis seroprevalence was 1.6% (C.I. = 0.8 to 2.8%) and the taeniasis prevalence 4.5% (C.I. = 3.0 to 6.5%). Seropositivity to cysticercosis was higher among those who lived in a house of a person testing positive for coproantigen, p=0.017.

CONCLUSION

our results demonstrate that the taeniasis-cysticercosis complex is endemic in Mulungu do Morro. We believe that all areas in the world with the same socio-economic and sanitary characteristics are likely to have high prevalence of this parasite.

Interrelationship between radiologic findings and prognosis of epilepsy in children with neurocysticercosis

INTRODUCTION

Epileptic manifestations of Neurocysticercosis (NC) appear to depend on number and localization of the cysts. The objective of this study was to investigate the relationship between CT findings, number of parasites and the evolutive stage of the cysts, and the prognosis of epilepsy in children with NC.

METHOD

We studied 28 patients with the parenchymal form of NC, considering: epilepsy duration; seizure frequency before and after AED treatment; seizure control; number of AED and recurrence after AED withdrawal. Clinical information was crossed with the number of lesions and disease activity in univariate comparison.

RESULTS

The analysis of the clinical data in relation to the number of lesions and disease activity showed no statistical difference among the variables (p>0.05).

CONCLUSION

We conclude that the course of epilepsy due to NC in childhood cannot be based exclusively on the number or stage of the parasites.

A rapid latex agglutination test for the detection of anti-cysticercus antibodies in cerebrospinal fluid (CSF)

Simple and rapid latex-based diagnostic tests have been used for detecting specific antigens or antibodies in several diseases. In this article, we present the preliminary results obtained with a latex agglutination test (LAT) for diagnosing neurocysticercosis by detection of antibodies in CSF. A total of 43 CSF samples were assayed by the LAT: 19 CSF samples from patients with neurocysticercosis and 24 CSF samples from patients with other neurologic disorders (neurosyphilis, n = 8; neurotoxoplasmosis, n = 3; viral meningitis, n = 4, chronic headache, n = 9). The LAT exhibited 89.5% sensitivity and 75% specificity. The use of LAT seems to be an additional approach for the screening of neurocysticercosis with advantage of simplicity and rapidity. Further studies could be performed using purified antigens and serum samples.

Frequency of serum anti-cysticercus antibodies in the population of a rural Brazilian community (Cássia dos coqueiros, SP) determined by Elisa and immunoblotting using Taenia crassiceps antigens

Considering the impact of cysticercosis on public health, especially the neurologic form of the disease, neurocysticercosis (NC), we studied the frequency of positivity of anti-Taenia solium cysticercus antibodies in serum samples from 1,863 inhabitants of Cássia dos Coqueiros, SP, a municipal district located 80 km from Ribeirão Preto, an area considered endemic for cysticercosis. The 1,863 samples were tested by enzyme linked immunosorbent assay (ELISA) using an antigenic extract from Taenia crassiceps vesicular fluid (Tcra). The reactive and inconclusive ELISA samples were tested by immunoblotting. Of the 459 samples submitted to immunoblotting, 40 were strongly immunoreactive to the immunodominant 18 and 14 kD peptides. Considering the use of immunoblotting as confirmatory due to its high specificity, the anti-cysticercus serum prevalence in this population was 2.1%.

An epidemiological study of Taenia solium cysticercosis in a rural population in the Bolivian Chaco

A survey of 100 rural households in a village in the Chaco region of Bolivia revealed a serious problem of Taenia solium cysticercosis, with a seroprevalence of 99/447 (22%) in humans and 102/273 (37%) in pigs. Risk factors for humans were being in older age groups, absence of sanitary facilities, poor formal education and inability to recognise infected pork. Significant risk indicators were a history of seizures and the reported elimination of worms in the faeces. Risk factors for pigs were being in older age groups and absence of sanitary facilities in the owner's house. The proportion of households with evidence of human cysticercosis was similar for those who owned pigs (48%) and those that did not (55%). This unexpected finding was attributed to the high overall prevalence of cysticercosis in pigs and the probability that everyone, regardless of pig-ownership, had ample opportunity to become infected in such communities. The main recommendation for reducing the prevalence of human cysticercosis was to provide more effective education campaigns, aimed at preventing both T. solium infection and cysticercosis.

Cognitive Performance of Patients with Epilepsy and Calcified Neurocysticercotic Lesions: A Case-Control Study

Neuropsychological tests were applied to 20 patients with focal epilepsy related to calcified neurocysticercosis (NCC) (mean: three lesions/patient; NCC group), 22 patients with focal epilepsy without NCC (EPI group), and 29 healthy controls matched for age, sex, and educational level. The EPI and NCC groups were matched for age at onset of epilepsy, epilepsy duration, frequency of attacks, seizure semiology, interictal EEG findings, and antiepileptic drugs used. There were no differences in the digit span, word span, calculus, and Mini-Mental State examination among the three groups studied. The NCC and EPI groups showed lower scores than controls in immediate and delayed verbal memory, famous faces test, spatial recognition span, abstractions and judgment, and visuoconstructional abilities. The EPI group, but not the NCC group, also had lower scores in a praxis tests. There were no differences between the NCC and EPI groups in any of the tests applied (P > 15), except for the spatial recognition span, which was lower in the former. Cognitive impairment is a prevalent neuropsychological feature of patients with epilepsy and NCC.

Serodiagnosis of human cysticercosis by using antigens from vesicular fluid of Taenia crassiceps cysticerci

Neurocysticercosis (NC), caused by the presence of Taenia solium metacestodes in tissues, is a severe parasitic infection of the central nervous system with universal distribution. To determine the efficiency of enzyme-linked immunosorbent assay (ELISA) and immunoblot with antigens of T. crassiceps vesicular fluid (Tcra) compared to standard techniques (indirect immunofluorescence test [IFT] and complement fixation test [CFT]) using T. solium cysticerci (Tso) for the serodiagnosis of NC, we studied serum samples from 24 patients with NC, 30 supposedly healthy individuals, 76 blood bank donors, 45 individuals with other non-NC parasitoses, and 97 samples from individuals screened for cysticercosis serology (SC). The sensitivity observed was 100% for ELISA-Tso and ELISA-Tcra, 91.7% for the IFT, and 87.5% for the CFT. The specificity was 90% for ELISA-Tso, 96.7% for ELISA-Tcra, 50% for IFT, and 63.3% for CFT. The efficiency was highest for ELISA-Tcra, followed by ELISA-Tso, IFT, and CFT. Of the 23 samples from SC group, which were reactive to ELISA-Tso and/or ELISA-Tcra, only 3 were positive to immunblot-Tcra (specific peptides of 14- and 18-kDa) and to glycoprotein peptides purified from Tcra antigen (gp-Tcra), showing the low predictive value of ELISA for screening. None of the samples from the remaining groups showed specific reactivity in immunoblot-Tcra. These results demonstrate that ELISA-Tcra can be used as a screening method for the serodiagnosis of NC and support the need for specific tests for confirmation of the results. The immunoblot can be used as a confirmatory test both with Tcra and gp-Tcra, with the latter having an advantage in terms of visualization of the results.

Cysticercosis in epileptic patients of Mulungu do Morro Northeastern Brazil

With the aim to study the magnitude of infection by the metacestode of Taenia solium in a population of epileptic patients in the arid region of Bahia, Northeastern Brazil, we examined 200 consecutive cases who attended an ambulatory clinic in the disctrict of Mulungu do Morro. Sixty-six of the patients had a diagnosis of epilepsy. From them 10 (15.2%) presented antibodies against a specific fraction of antigens in Western blot, and 4 (6.0%) had circulating parasite products, as tested by capture ELISA. Only 1 case was positive for antibodies and antigens. We found that the frequency of seropositivity was related to the time without epileptic seizure. We conclude that cysticercosis is endemic in the region of Mulungu do Morro and that it is related to a benign form of epilepsy.

A quantitative enzyme-linked immunosorbent assay (ELISA) for the immunodiagnosis of neurocysticercosis using a purified fraction from Taenia solium cysticerci

A quantitative enzyme-linked immunosorbent assay (ELISA) for the immunodiagnosis of neurocysticercosis is described. The ELISA was standardized using a purified Taenia solium cysticerci fraction (PCF) obtained by ion exchange chromatography. The ELISA using PCF (PCF-ELISA) and a qualitative ELISA using a whole extract from T. solium cysticerci (WEC-ELISA) were used to screen for cysticercus-specific IgG antibodies in cerebrospinal fluid (CSF) samples from 57 patients with neurocysticercosis and 50 patients with other neurologic disorders. The sensitivity of both assays was 95%, whereas the specificities of PCF-ELISA and WEC-ELISA were 100% and 92%, respectively. The excellent sensitivity and specificity of the PCF-ELISA make this assay a potentially useful tool in screening for antibodies against T. solium cysticerci.

Clinical aspects of neurocysticercosis in children

The purpose of this report was to evaluate the clinical aspects of neurocysticercosis in children from a Brazilian region. A retrospective study of 25 children with this neuroparasitosis was performed. The diagnosis was based on clinical, cerebrospinal fluid, and neuroimaging findings. The patients were predominantly male (72%), were 1 to 11 years of age (average = 8 years, 6 months), and most resided in urban areas (68%). The more frequent manifestations were epileptic seizures (72%), headache (60%), learning disability (24%), behavioral changes (12%), psychomotor involution (8%), and intracranial hypertension (4%). The neurologic examination was normal in 80% of the patients. Twenty-two children received only symptomatic drugs. Three patients underwent treatment with cysticidal drugs, one with praziquantel and two with albendazole, with complete remission of the signs in one patient (33%) and improvement in two others (67%). Of the 25 patients, 43.4% had remission and 47.8% had improvement. We emphasize the need to consider neurocysticercosis as a differential diagnosis in children coming from endemic areas and presenting with learning disabilities, behavioral changes, and psychomotor involution. The clinical aspects in most of the children from the Botucatu region suggest a spontaneous resolution of neurocysticercosis without the need for cysticidal treatment.

Total IgE detection in paired cerebrospinal fluid and serum samples from patients with neurocysticercosis

Neurocysticercosis (NC), the presence of Taenia solium metacestodes in tissues, is the most frequent and severe parasitic infection of the central nervous system. We investigated the presence of total IgE by an automated chemiluminescence assay in 53 paired cerebrospinal fluid (CSF) and serum samples from patients with NC (P) and in 40 CSF samples from individuals with other neurological disorders as the control group (C). Total IgE concentration ranged from 1.2 to 6.6 IU/ml (mean = 1.4 IU/ml, standard deviation-sd = 1.1 IU/ml) in 28.3% of CSF samples from the P group, a value significantly higher than for the C group ( pound1.0 IU/ml). The serum samples from the P group showed concentrations ranging from 1. 0 to 2330.0 IU/ml (mean = 224.1 IU/ml, sd = 452.1 IU/ml), which were higher than the normal value cited by the manufacturer (<100.0 IU/ml) in 32.1% of the samples. A significant difference was observed in CSF samples from the P and C groups (p = 0.005) and in serum samples from the P group compared to the normal value (p = 0. 005), with sera showing more frequent abnormal results.

Neurocysticercosis: detection of IgG, IgA and IgE antibodies in cerebrospinal fluid, serum and saliva samples by ELISA with Taenia solium and Taenia crassiceps antigens

We assayed samples of cerebrospinal fluid (CSF), serum and saliva from patients with neurocysticercoses, control group and individuals with other parasitoses, by ELISA with Taenia crassiceps vesicular fluid antigen (Tcra) and Taenia solium total antigen (Tso) for the detection of antibodies. The sensitivity for IgG-Tcra was 100% for CSF and serum, and 32.0% for saliva; and for IgG-Tso 100% for CSF, 80.0% for serum and 24.% for saliva. Specificity was 100% for CSF and 80.0% for serum with both antigens, and 100% for saliva with Tcra and 87.5% with Tso. The sensitivity and specificity for IgA-Tcra was, respectively, 40.0% and 100% for CSF, 36.0% and 97.1% for serum, and 4.0% and 90.0% for saliva. IgE detection showed 24.0% sensitivity and 97.1% specificity for serum, with no detection in CSF samples. The search for antibodies revealed the presence of IgG > IgA > IgE in CSF, serum and saliva samples, with IgG being present in all phases of the disease, while IgA/IgE were more frequent in the inactive form.

Specific Taenia crassiceps and Taenia solium antigenic peptides for neurocysticercosis immunodiagnosis using serum samples

Neurocysticercosis (NC), i.e., the presence of the larval form of Taenia solium in tissues, is the most frequent and severe infection involving the central nervous system. Paired serum and cerebrospinal fluid (CSF) samples from patients with NC, CSF and serum samples from a control group, and serum samples from patients with other parasitoses were studied by enzyme-linked immunosorbent assay (ELISA) and by immunoblotting with Taenia crassiceps vesicular fluid antigen (Tcra) and Taenia solium total saline antigen (Tso) for the detection of immunoglobulin G antibodies. ELISAs carried out with the Tso and Tcra antigens showed 94.1 and 95.6% sensitivities, respectively, for the detection of antibodies in CSF and 70.6% and 91.2% sensitivities, respectively, for the detection of antibodies in serum, with 100% specificity for the detection of antibodies in CSF and 80% specificity for the detection of antibodies in serum for both antigens. On the basis of the reactivities of the peptides in the samples analyzed, the peptides of </=23, 39, 85 to 77, and 97 kDa were found to be Tso specific by immunoblotting and the peptides of </=62, 74, 109, 121, and 131 kDa were found to be Tcra specific. Tests with Tcra extract had higher sensitivities and more homogeneous results and permitted us to obtain the parasites easily. We suggest the use of Tcra ELISA for the study of serum and confirmation of the results for sera positive by an immunoblotting analysis in which specific peptides (e.g., peptides of 19 to 13 kDa) are detected.

[Occurrence of encephalic and cardiac cysticercosis (Cysticercus cellulosae) in necropsy]

OBJECTIVE

To review the incidence and pathologic findings of cysticercosis diagnosed at autopsies, with emphasis on the most common organs affected.

METHODS

Reports of 1.596 autopsies performed between 1974 and 1997 at a school hospital in Uberaba, MG, Brazil were studied. The following data were obtained: age, sex, ethnic group, body mass index, and the site of the cysticercosis.

RESULTS

The study found diagnosis of cysticercosis in 53 autopsies (3.3%). The average age of patients with cysticercosis was 50 (range: 15 to 86 years); 62.3% were male, and 64.1% Caucasian. The most affected organs were: brain (79.2%), heart (22.6%), skeletal muscle (11.3%), and other organs (5.7%). No statistical differences were found comparing age, gender, ethnic group, and body mass index of the affected and the non-affected patients. In two cases of neurocysticercosis the lesions were located in the ventromedial nucleus of the hypothalamus.

CONCLUSION

Both the overall incidence of cysticercosis and the incidence of cardiac cysticercosis were greater in the study than in other autopsy series from the same geographic areas. In two cases there was an association between hypothalamic cysticercosis and obesity

Lack of association between parenchymal neurocysticercosis and HLA Class I and Class II antigens

Neurocysticercosis, caused by encysted larvae of the tapeworm Taenia solium, is the most common infection of the central nervous system and a major public health problem in many countries. Prevalence in the region of Curitiba, located in the southern Brazilian State of Paraná, is one of the highest in the world. The genetics of host susceptibility to neurocysticercosis (NCC) is still obscure. To investigate if major histocompatibility complex (MHC) genes influence individual susceptibility to NCC, we performed a case-control association analysis. Fifty-two Caucasoid patients and 149 matched controls were typed for antigens of the HLA-A, B, C, DR and DQ loci. All patients had computerized tomography and clinical features compatible with parenchymal NCC. Indirect immunofluorescence of cerebrospinal fluid showed that 19 (37%) of the patients presented anti-cysticercus antibodies at titers <FONT FACE="Symbol">³</font> 1:10. Frequencies of HLA specificities in the whole group of patients and in the subgroup with antibodies in cerebrospinal fluid were compared to those of the control group. No significant difference was found. These results do not support the hypothesis of HLA gene participation in susceptibility to parenchymal neurocysticercosis.