Histopathologic aspects of experimental cysticercosis and in situ cytokines profile in C57BL/6 mice / Aspectos histopatológicos da cisticercose experimental e perfil de citocinas in situ em camundongos C57BL/6

ABSTRACT Neurocysticercosis (NCC) is one of the parasitic infections that most affects the central nervous system. The knowledge regarding its immunopathogenesis and pathophysiology needs broadening. Taenia crassiceps cysticerci are used as the NCC experimental model. The aim of this work was to describe the general pathological processes and the in situ cytokine profile in C57BL/6 mice inoculated intracranially with viable T. crassiceps cysticerci. The histopathology analysis showed cysticerci in the extraparenchymal and intraventricular region, mononuclear inflammatory infiltration surrounding the parasite, microgliosis and meningitis. The analysis of the in situ immune profiles showed a predominance of the Th2 response. The IL-4 and IL-10 dosages were significantly increased in the infected group. The decrease in the INF-gamma dosage reflects the immunomodulation from the cysticerci. In conclusion, a T. crassiceps NCC infection in C57BL/6 mice triggers an inflammatory response, a predominance of Th2 type in situ profile, with mononuclear inflammatory cell infiltration, meningitis and microgliosis.

RESUMO Neurocisticercose (NCC) é uma das doenças parasitárias que mais afeta o sistema nervoso central. É necessário aprofundar o conhecimento em relação à sua imunopatogênese e patofisiologia. Os cisticercos de Taenia crassiceps são utilizados como modelo experimental para estudos da NCC. O objetivo deste trabalho foi descrever os processos patológicos gerais e o perfil de citocinas in situ em camundongos C57BL/6 inoculados via intracerebral com cisticercos viáveis de T. crassiceps. A análise histopatológica demonstrou cisticercos nas regiões extra-parenquimatosa e intraventricular, infiltrado inflamatório de células mononucleares ao redor do parasita, microgliose e meningite. A análise in situ do perfil de citocinas mostrou uma predominância da resposta Th2. As dosagens de IL-4 e IL-10 foram significativamente maiores no grupo infectado. Conclui-se que a NCC por T. crassiceps em camundongos C57BL/6 induz uma resposta inflamatória com predominância in situ de citocinas do perfil Th2, com infiltrado inflamatório de células mononucleares, meningite e microgliose.

Validez de tres métodos de inmuno-diagnóstico de neurocisticercosis: revisión sistemática de la literatura con meta-análisis 1960-2014 / Validity of three methods for inmuno-diagnostic of neurocysticercosis: systematic review of the literature with meta-analysis 1960-2014

Introduction: The screening of neurocysticercosis is complex and immunological methods have varying validity. Objective: To evaluate the validity of ELISA for antigen and antibody, and EITB for antibody in the screening of neurocysticercosis. Methods: Meta-analysis of diagnostic tests with an ex-ante protocol implemented in five databases with 15 search strategies, ensuring reproducibility in the selection and extraction of information. Sensitivity, specificity, likelihood ratios (LR), diagnostic odds ratio and ROC curve were estimated in MetaDiSc, and predictive values, and Youden index were estimated in Epidat. Results: EITB presented sensitivity of 85.7% (95% CI 83.5-87.7), specificity 93.9% (95% CI = 92.7-95.0), PLR 19.6 (95% CI = 8,6-44.6), NLR 0.16 (95% CI = 0.12-0.21), OR diagnostic 136.2 (95% CI = 54.7-342.6) and area under the curve 0.926. In ELISA for antibody sensitivity was 87.5% (95% CI = 86.1-88.8), specificity 92.2% (95% CI = 91.4-93.0), PLR 11.3 (95% CI = 8.45-15.11), NLR 0.15 (95% CI = 0.13-0.18), diagnostic OR 87.4 (95% CI = 60.1-127.1) and area under the curve 0.950. ELISA for antigen showed low diagnostic validity. No differences were found in these parameters by sample, antigen or antibody type. Conclusion: ELISA for antibodies and EITB have a similar diagnostic value, detection of serum and CSF showed a similar validity.

Introducción: La tamización de neurocisticercosis es compleja y los métodos inmunológicos presentan validez variable y generalmente bajos tamaños de muestra. Objetivo: Evaluar la validez de ELISA para detección de antígeno y anticuerpo, y EITB para detección de anticuerpo en la tamización de neurocisticercosis. Métodos: Meta-análisis de pruebas diagnósticas con un protocolo ex-ante aplicado en cinco bases de datos con 15 estrategias de búsqueda, garantizando reproducibilidad en la selección y extracción de la información. Se estimó sensibilidad, especificidad, cocientes de probabilidad (CP), razón de odds diagnósticas y curva ROC en MetaDiSC, y valores predictores, índice de Youden y exactitud en Epidat. Resultados: EITB presentó sensibilidad de 85,7% (IC 95% = 83,5-87,7), especificidad 93,9% (IC9 5% = 92,7-95,0), CPP 19,6 (IC 95% = 8,6-44,6), CPN 0,16 (IC 95% = 0,12-0,21), OR diagnóstica 136,2 (IC 95% = 54,7-342,6) y área bajo la curva 0,926. En ELISA para anticuerpos la sensibilidad fue 87,5% (IC 95% = 86,1-88,8), especificidad 92,2% (IC 95% = 91,4-93,0), CPP 11,3 (IC 95% = 8,45-15,11), CPN 0,15 (IC 95% = 0,13-0,18), OR diagnóstica 87,4 (IC 95% = 60,1-127,1) y área bajo la curva 0,950. ELISA para antígeno presentó baja validez diagnóstica. No se hallaron diferencias en estos parámetros según tipo de muestra, antígeno o anticuerpo. Conclusión: ELISA para anticuerpos y EITB presentan una utilidad diagnóstica similar, la detección de suero presentó una validez similar al líquido cefalorraquídeo.

Seroepidemiological study of human cysticercosis with blood samples collected on filter paper, in Lages, State of Santa Catarina, Brazil, 2004-2005 / Estudo soroepidemiológico da cisticercose humana com amostras de sangue total coletado em papel filtro, em Lages, Estado de Santa Catarina, 2004-2005

INTRODUCTION: Human serofrequency of antibodies against Taenia solium antigens was determined and risk factors for cysticercosis transmission were identified. METHODS: Individuals (n=878) from periurban and rural locations of Lages, SC, were interviewed to gather demographic, sanitary and health information. Interviews and blood sample collections by finger prick on Whatman filter paper were performed from August 2004 to May 2005. Observation determined that 850 samples were suitable for analysis and were tested by ELISA using vesicular fluid of Taenia crassiceps heterologous antigen. To ensure the reliability of the results, 77 samples of the dried blood were matched with sera. The reactive samples were submitted to a serum confirmatory immunoblot (IB) test using purified Taenia crassiceps glycoproteins. RESULTS: The ELISA results for the dried blood and serum samples were statistically consistent. ELISA was positive in 186 (21.9 percent) out of 850 individuals. A group of 213 individuals were asked to collect vein blood for IB (186 with positive result in ELISA and 27 with inappropriate whole blood samples) and 130 attended the request. The IB was positive in 29 (3.4 percent) out of 850 individuals. A significant correlation (p = 0.0364) was determined among individuals who tested positive in the IB assay who practiced both pig rearing and kitchen gardening. CONCLUSIONS: ELISA with dried blood eluted from filter paper was suitable for cysticercosis population surveys. In Lages, human infection was associated with pig rearing and kitchen gardening. The prevalence index was compatible with other Latin American endemic areas.

INTRODUÇÃO: O primeiro levantamento sobre cisticercose humana e identificação dos fatores de risco associados à transmissão, foram realizados em Lages, SC. MÉTODOS: Oitocentos e setenta e sete voluntários de regiões periurbana e rural foram entrevistados e forneceram informações demográficas e condições sanitárias e de saúde. Amostras de sangue foram coletadas por meio de punção digital em papel filtro entre agosto 2004 e maio 2005. Verificou-se que 850 amostras estavam adequadas para análise. No ELISA, utilizou-se o antígeno heterólogo liquido vesicular de Taenia crassiceps. Para assegurar a confiabilidade dos resultados de ELISA, foram pareadas 77 amostras de soro e sangue eluido do papel filtro. A confirmação do diagnóstico sorológico foi feita por immunoblot (IB) com glicoproteínas purificadas de Taenia crassiceps. RESULTADOS: A reatividade de IgG eluída de sangue em papel filtro mostrou-se compatível com a dos soros correspondentes. A triagem por ELISA de 850 indivíduos revelou 186 (21,9 por cento) positivos. De 213 pessoas convidadas a colher soro para IB (186 ELISA positivo e 27 com amostras de sangue total inadequadas), compareceram 130. O IB foi positivo em 29 (3,4 por cento) de 850 amostras. Houve correlação significativa entre IB positivo e a prática de criação de suínos e de horta caseira (p = 0,0364). CONCLUSÕES: ELISA com sangue total em papel filtro mostrou-se adequado para inquéritos populacionais para cisticercose. A transmissão da cisticercose humana na área estudada mostrou correlação com criação suína domestica e horta caseira. A prevalência obtida foi semelhante à relatada em áreas endêmicas da América Latina.

Neurocysticercosis: relationship between Taenia antigen levels in CSF and MRI / Neurocisticercose: relação entre antígeno da Taenia no líquido cefalorraquidiano e ressonância magnética

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 percent). 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 percent of all lesions), 22.1 percent were degenerating cysts and 19.5 percent 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.

Objetivo: Determinar a relação entre a detecção de antígeno de Taenia (TA) no líquido cefalorraquidiano (LCR) e achados de ressonância magnética (RM) em pacientes com diagnóstico definitivo de neurocisticersose. Método: Sessenta e três pacientes com diagnóstico de NC foram submetidos a exame de RM e exame de LCR com pesquisa de antígeno de Taenia por método imunoenzimático. Resultados: A detecção de TA foi positiva em 36 pacientes (57,1 por cento). Um total de 836 lesões foram analizadas sendo 98,7 por cento intraparemquimatosas, 50,4 por cento dos cistos encontravam-se íntegros, 22,1 por cento degenerados e 19,5 por cento calcificados. Foi observada relação significativa entre a presença dos níveis de TA detectados com o número total dos cistos e também com o número de cistos íntegros. Não foi observada relação com cistos calcificados. Conclusão: (1) a detecção de TA permite o diagnóstico etiológico em formas transicionais na NC com imagem pouco característica; (2) em estágio evolutivo final de um cisticerco no sistema nervoso, este pode não aparecer na tomografia computadorizada ou RM sendo a presença do antígeno importante para confirmação diagnóstica; (3) a detecção do TA permite também o diagnóstico de NC nos casos em que as reações inumológicas são negativas; (4) a detecção do TA representa um marcador de atividade da doença nas formas epiléticas da NC.

Conocimiento y prácticas sobre Teniasis-cisticercosis en una comunidad colombiana / Knowledge and practices concerning taeniasis-cysticercosis in Colombian pig-breeders

Objetivo Determinar los conocimientos y prácticas sobre teniasis-cisticercosis y la frecuencia de anticuerpos contra Taenia solium en habitantes de la localidad de Andagoya, Colombia. Métodos Se realizó un estudio cualitativo-cuantitativo. Las poblaciones de estudio fueron los criadores de cerdos y sus familias, población local y cerdos. Resultados La población tiene un conocimiento parcial del complejo teniasis-cisticercosis. Identifica la cisticercosis como una enfermedad sólo del cerdo y no del humano, considera la teniasis como una enfermedad de transmisión fecal y no ocasionada por el consumo de carne de cerdo con cisticercosis. La crianza de cerdos no se hace en confinamiento y aunque se conocen los hábitos higiénicos para el control de enfermedades parasitarias su cumplimiento no es adecuado. La presencia de anticuerpos contra T. solium en los criadores de cerdos y sus familiares fue del 8,7 por ciento y en los cerdos del 20,9 por ciento. Conclusión Se debe desarrollar un programa educativo sobre teniasis-cisticercosis que permita sensibilizar a la población para el conocimiento y la aplicación de medidas de control.

Objective Describing knowledge and practices regarding taeniasis-cysticercosis and cysticercosis prevalence in the village of Andagoya, Colombia. Methods The study design was qualitative and quantitative. The study population consisted of pig breeders and their families, local groups and pigs. Results Study participants had partial knowledge of the taeniasis-cysticercosis complex. They considered taeniasis to be an illness resulting from faecal transmission and not caused by becoming infected with cysticercosis after consuming pork. Pig breeding is not carried out in confined conditions and, although breeders know the right measures for controlling some parasitic illnesses, these practices are not observed. There was 8.7 percent presence of T. solium antibodies in pig breeders and their relatives and 20.9 percent in the pigs. Conclusions An educational programme aimed at raising the population's awareness of the taeniasis-cysticercosis complex cycle should be developed; this will facilitate control measures being applied.

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 percent sensitivity and 94.3 percent specificity, whereas the sensitivity and specificity of the ELISA for the whole Taenia crassiceps cysticercal extract were 87 percent and 94.3 percent, respectively. The ELISA reactions for vesicular fluid from Taenia solium or Taenia crassiceps showed 91.3 percent sensitivity and 97.1 percent 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.

A eficácia de extratos antigênicos de parasitas totais e líquido vesicular de cisticercos de Taenia solium e Taenia crassiceps para o imunodiagnóstico da neurocisticercose foi avaliada por meio de reações de ELISA em amostras de líquido cefalorraquidiano. Anticorpos IgG anti-cisticercos foram pesquisados em amostras de líquido cefalorraquidiano de 23 pacientes com neurocisticercose e 35 pacientes com outras doenças neurológicas. A reação ELISA com o extrato bruto total de cisticercos de Taenia solium apresentou 91,3 por cento de sensibilidade e 94,3 por cento de especificidade, enquanto a sensibilidade e a especificidade da reação ELISA com o extrato total de cisticercos de Taenia crassiceps foram 87 por cento e 94,3 por cento, respectivamente. As reações ELISA com o líquido vesicular de Taenia solium ou Taenia crassiceps mostraram 91,3 por cento de sensibilidade e 97,1 por cento de especificidade. Considerando os resultados obtidos com as quatro preparações antigênicas, o liquido vesicular de cisticercos de Taenia solium e Taenia crassiceps pode ser útil como fonte de antígenos em reações imunológicas usadas para detectar anticorpos específicos em amostras de líquido cefalorraquidiano de pacientes com neurocisticercose.

Tratamiento de la neurocisticercosis: revisión critica / Treatment of neurocysticercosis: a review

Neurocysticercosis (NCC) is the most common parasitic disease of the central nervous system. Several drugs, such as drugs against tapeworms, praziquantel or albendazole associated to corticosteroids, have been tested for the treatment of this condition. Although some have claimed the reduction or involution of cystic or granulomatous lesions, there is no consensus about the efficacy of these treatments. The natural evolution of the disease is not clear and this hampers the assessment of treatment effects. Moreover, there are no good imaging or clinical indicators that can predict the progression or spontaneous resolution of lesions, specially at the meningeal or ventricular compartment. Therefore, evidence based medicine does not have a definitive answer about the treatment, neither of seizures, the most common manifestation of NCC, or the varied and complex meningeal and ventricular involvement. This review includes experts opinions to give the clinician some clues for decision making in the treatment of NCC.

Neurocisticercose: relação entre dosagem de antígenos de taenia no líquido cefalorraquidiano e imagem através de ressonância magnética / Neurocysticercosis: relationship between taenia antigen detection in the cerebrospinal fluid and magnetic resonance imaging

Neurocisticercose (NC) é a doença parasitária mais comum do SNC, representando grave problema de saúde pública em nosso país. O diagnóstico da NC é baseado em dados clínicos e epidemiológicos, reações sorológicas no soro e LCR, além de exames de neuroimagem. A detecção de antígenos de Taenia através de teste de ELISA, mediante a utilização de anticorpos altamente purificados, constitui metodologia recente capaz de informar sobre a vigência de atividade clínica da doença. O objetivo deste estudo foi determinar a relação entre a dosagem de antígenos de Taenia mo LCR com as imagens obtidas através da RM, em pacientes com o diagnóstico definido de NC segundo os critérios diagnósticos atuais. Sessenta e três pacientes foram submetidos a exame detalhado do LCR, além de pesquisa de antígeno de Taenia através de teste de ELISA, utilizando anticorpos de soro de coelhos imunizados com líquido vesicular de Taenia crassiceps. Uma amostra de sangue foi colhida simultaneamente à coleta do LCR, e um exame de RM encefálica foi realizado em todos os pacientes. Observamos relação significativa entre a detecção de antígenos de Taenia e o número total de lesões e do número de cistos íntegros detectados pela RM. Quando comparados dois ou mais cistos em degeneração com apenas um cisto, observamos detecção significativamente mais alta no primeiro grupo. Encontramos também detecção de antígenos significativamente mais alta quando as lesões se localizavam na profundidade dos hemisférios cerebrais, mas não na presença de cistos calcificados. Os resultados demonstram que a detecção de antígenos de Taenia se mostra congruente com os achados de neuroimagem. Algumas outras variáveis estudadas no LCR, como número de células, teor de globulinas gama e teste de ELISA, também se mostraram concordantes, demonstrando que a resposta inflamatória na NC mobiliza tanto a imunidade celular quanto a imunidade humoral.

Neurocysticercosis (NC) is the most common parasitic infection of the nervous system, remaining a serious public health in our country. NC diagnosis is supported by clinical and epidemiological data, specific serological reactions in the blood and CSF, and neuroimaging findings. Detection of anti-Taenia antigens using ELISA techniques is a recent methodology that provides information about clinical activity of the disease. The objective of the study was to determine relationship between Taenia antigen detection in the CSF and MRI in patients with definite diagnosis of NC according to current diagnostic criteria. Sixty-three patients were submitted to a thorough CSF examination and Taenia antigen research. Antigens were detected in CSF samples by ELISA assay obtained from rabbit sera antibodies immunized with Taenia crassiceps cysticerci vesicular fluid. A blood sample was simultaneously collected and a MRI was performed in every patient. We observed a significant relationship between Taenia antigen detection and the total number of lesions and intact cysts detected by MRI. When comparing two or more degenerating cysts with only one we observed a significant higher antigen detection in the first group. We also found a significant higher antigen detection when cysts were deeply located in the cerebral hemispheres, but not in the presence of calcified cysts. Results demonstrate that Taenia antigen detection is congruent with neuroimaging findings. Some CSF characteristics, like number of cells, gamma globulin concentration and ELISA assay were also concordant with Taenia antigen detection, indicating that inflammatory reaction in NC comprise cellular and humoral immunological factors.

Taenia antigens detection in the cerebrospinal fluid of patients with neurocysticercosis and its relationship with clinical activity of the disease

OBJETIVO: (1) Determinar a concentração de antígenos de Taenia no líquido cefalorraquidiano (LCR) em doentes com neurocisticercose; (2) estudar sua relação com a atividade clínica da doença e com as variáveis clássicas do LCR. MÉTODO: Em 36 pacientes com diagnóstico definido de neurocisticercose foi realizado exame do LCR, com estudo citológico e citomorfológico, exame bioquímico, reações imunológicas para cisticercose e detecção de antígenos de Taenia. Os anticorpos para detecção desses antígenos foram obtidos a partir da forma larvar da Taenia crassiceps, cepa ORF. Após a inoculação e proliferação intraperitoneal dessa forma larvária em ratas, foi imunizado um grupo de coelhos com seu líquido vesicular. RESULTADOS: Em 17 pacientes (47,2%) foi detectado antígeno de Taenia, especialmente naqueles com manifestação epiléptica nos últimos 12 meses. CONCLUSÃO: A detecção de antígeno de Taenia guarda relação significativa com a vigência de formas clinicamente ativas, sendo, nestas formas, marcador mais sensível que a eosinofilorraquia.

Vaccination against Taenia solium cysticercosis

Taenia solium is a parasite that causes human cysticercosis. Its life cycle includes the adult stage, the egg and the larval stage. Human cysticercosis is a disease related to underdevelopment, the main clinical manifestation is neurocysticercosis. Control measures include mass cestocidal treatment aimed to cure possible taeniosis cases. Although useful it has certain disadvantages, such as the generation of symptomatology in occult neurocysticercosis. Alternatively, health education has been shown to be highly effective since people become aware of the importance of human and porcine cysticercosis and the possibility of eliminating it. Nevertheless it has to be implemented by knowledgeable people. On the other hand, the life cycle can be controlled by avoiding swine cysticercosis. This review describes the studies performed to vaccinate pigs against T. solium and indicate that short time perspectives are very encouraging for the production of an optimal vaccine

Differential serodiagnosis of cystic and alveolar echinococcosis using native and recombinant antigens in Japan.

Our group at Asahikawa Medical College has established differential serodiagnosis for zoonotic larval cestodiases such as alveolar echinococcosis (AE), cystic echinococcosis (CE) and neurocysticercosis (NCC) using purified specific antigens. In this brief review, we introduce (a) four imported CE cases in Japan, easily identified serologically, (b) most recent advances in serology for differentiation of AE and monitoring of prognosis of AE in Japan. It includes application of affinity purified Em18 and prototype of a recombinant Em18 antigen. Serology using affinity purified Em18 antigens is showing much higher sensitivity for detection of AE cases which are usually undetectable by the ongoing serology for AE authorized in Hokkaido, Japan. As serology for AE, CE or NCC is still not popular in the majority of Asian countries, we expect that this review paper stimulates researchers who are interested in serology or serodiagnosis for these larval cestodiases including AE, CE and NCC.

Production of monoclonal antibodies anti-Taenia crassiceps cysticerci with cross-reactivity with Taenia solium antigens

We describe the production of the potential monoclonal antibodies (MoAbs) using BALB/c mice immunized with vesicular fluid (VF)-Tcra (T. crassiceps) antigen. Immune sera presented anti-VF-Tcra (<20kD) IgG and IgM antibodies with cross-reactivity with T. solium (Tso) antigen (8-12, 14, and 18 kD). After cell fusion, we selected 33 anti-Tcra and anti-Tso reactive IgM-clones and 53 anti-Tcra specific IgG-clones, 5 of them also recognizing Tso antigens. Two clones identified the 8-14 and 18kD peptides of VF-Tcra.

Cisticercose: fatores relacionados à interaçäo parasito-hospedeiro, diagnóstico e soroprevalência / Aspects of the host/parasite interacion, diagnosis and seroprevalence of cysticercosis

A cistecercose humana é uma doença caracterizada pela presença de larva metacestóidea de Taenia solium nos tecidos e decorrente da ingestäo acidental de ovos viáveis, provenientes da matéria decal de indivíduos portadores do verme adulto. Dentre as possíveis localizaçöes do cisticerco, destaca-se o Sistema Nervoso Central (SNC) pelo poliformismo, pela gravidade dos sintomas e pelas dificuldades diagnósticas. O curso da doença é particularmente dependente de uma variedade de reaçöes imunes e inflamatórias desencadeadas pela interaçäo parasito-hospedeiro, que se desenvolve em diferentes graus de complexidade, desde a ativaçäo e migraçäo das oncosferas, a partir da luz do intestino delgado, até a implantaçäo e sobrevida da larva em tecidos do organismo hospedeiro. O estágio de evoluçäo, a quantidade e a localizaçäo dos cisticercos exercem açäo sobre a sintomatologia e podem influenciar nos diagnósticos imunológico e por imagem. O duagnóstico definitivo somente pode ser firmado através da demonstraçäo do parasito por pesquisa direta; entretanto, questöes de ordem técnica e de caráter invasivo limitam seu emprego. Devido ao alto custo, a tomografia computadorizada e a ressonância nuclear magnética näo säo acessíveis à maioria da populaçäo...

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 per cent for CSF and serum, and 32.0 per cent for saliva; and for IgG-Tso 100 per cent for CSF, 80.0 per cent for serum and 24 per cent for saliva. Specificity was 100 per cent for CSF and 80.0 per cent for serum with both antigens, and 100 per cent for saliva with Tcra and 87.5 per cent with Tso. The sensitivity and specificity for IgA-Tcra was, respectively, 40.0 per cent and 100 per cent for CSF, 36.0 per cent and 97.1 per cent for serum, and 4.0 per cent and 90.0 per cent for saliva. IgE detection showed 24.0 per cent sensitivity and 97.1 per cent 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.

Neurocysticercosis: utilizing the cystic fluid antigen from Taenia solium metacestodes for diagnosis by IgG-ELISA.

Cystic fluid, which has antigenic properties of whole Taenia solium cysticerci, was used to discriminate neurocysticercosis cases and other parasitic infections, especially helminthiases. Twenty-one neurocysticercosis and several kinds of 22 different parasitic infections, including HIV cases (n=234) evaluated a 90.48% sensitivity and 86.32% specificity of indirect ELISA as follows: a low antigen concentration of 5 microg/ml. serum dilution of 1:400, conjugate dilution of 1:2,000 and a cut-off value of 0.349. Eight different helminthic infections (n = 25); echinococcosis (8/10), gnathostomiasis (6/8), strongyloidiasis (5/14), hookworm infection (1/18), angiostrongyliasis (2/25), opisthorchiasis (1/18), onchocercosis (1/3) and toxocariasis (1/6) were cross-reactive with this antigen. No serum antibody from other brain infections in the study gave a reaction with the antigen. In this study, the cystic fluid antigen gave high sensitivity of the test. However, the antigen contains various antigenic molecules able to bind with antibodies from several of the above helminthic sera, especially echinococcosis and gnathostomiasis. In Thailand, gnathostomiasis is one of the more famous tropical diseases but echinococcosis is quite rare. Cystic fluid antigen should be further investigated for its specific finding in diagnosis.

Neurocysticercosis and echinococcosis in Asia: recent advances in the establishment of highly reliable differential serodiagnosis for international collaboration.

Neurocysticercosis (NCC) and echinococcosis, caused by the larval stage of taeniid cestodes, are recognized as major parasitic zoonoses threatening human life worldwide. Cystic echinococcosis (CE), caused by Echinococcus granulosus, has well been known to be more widely distributing in Europe and Asia (Eurasia) than alveolar echinococcosis (AE) caused by E. multilocularis. However, it has recently been found that AE is more widely distributing or spreading in Eurasia. Furthermore, NCC caused by Taenia solium is also spreading in Eurasia. Due to the lack of reliable methodology for diagnosing these zoonotic cestodiases worldwide, prevalence rates of these diseases are extremely underestimated. Our group has been working for the establishment of differential serodiagnosis and molecular diagnosis of AE. CE and NCC as international collaboration projects sponsored by the Ministry of Education, Japan from 1994 until 2000 at least. In this paper, we introduce (1) the most recent original work on the establishment of differential serodiagnoses of NCC, AE and CE, (2) international collaboration work on epidemiology of these diseases in several countries, and discuss (3) what we can and should do for the control of such global parasitic diseases. It is stressed that international collaboration or cooperation work on the control of parasitic diseases is only successful based on the original scientific contribution of high standard.

Determinación y caracterización de antígenos de cisticercus de T. solium, reconocidos por líquidos cefalorraquídeos de pacientes con neurocisticercosis / Determination and characterization of T. solium cysticercus antigens, recognized by cerebrospinal fluid from neurocysticercosis patients

La cisticercosis humana es una parasitosis causada por T. solium la cual posee una alta prevalencia en aíses en desarrollo constituyéndose en un problema de salud pública, y en donde la neurocisticosis (NCC) es su forma más grave ya que compromete el sistema nervioso central (SNC). Debido a que las técnicas desarrolladas para el inmunodiagnóstico de NCC presentan problemas de sensibilidad y especificidad, en éste estudio se desarrollo un método analítico sensible para la identificación de antígenos específicos de cisticerco de T. solium reconocidos por líquidos cefalorraquídeos (LCRs) de pacientes con (NCC). La identificación de un número definido de antígenos de T. solium potenciales para el inmunodiagnóstico permitiría posteriormente la purificación de proteínas para el desarrollo de técnicas inmunodiagnósticas. Los antígenos presentes en LIV de cisticerco, fueron modificados químicamente empleando Biotina-NHS (Biotin-Amido-Caproato-N-hidroxisuccinimida éster) seguido por una inmunoprecipitación utiliando LCR. Los complejos antígeno-anticuerpo fueron capturados empleando agarosa anti IgG humana y posteriormente, las proteínas resueltas por electroforesis, seguida de transferencia a papel de nitrocelulosa. Los antígenos biotinilados, fueron reconocidos utilizando estreptavidina conjugada a fosfatasa alcalina y la reacción se visualizó empleando el sustrato NBT (nitro blue tetrazolium) y BCIP (4-cloro-5-bromo-4cloro-3-indolyl phospahate) (Sigma). Se identificaron 5 polipeptidos principales de 100 kDa, 70 kDa, 50 kDa, 35 kDa y 24 kDa por el ensayo de inmunoprecipitación. Los polipéptidos de 100 kDa, 50 kDa y 24 kDa dueron reconocidos por LCRs de pacientes clínica y serológicamente positivos por ELISA para NCC (94 por ciento, 94 por ciento y 78 por ciento respectivamente), además éstos antígenos fueron reconocidos por LCRs de pacientes con otras neuropatologías de SNC (94 por ciento, 76 por ciento y 47 por ciento respectivamente) e igualmente por LCRs de pacientes sospechosos clínicamente pero serológicamente negativos por ELISA para NCC (21 por ciento, 24 por ciento, y 13 por ciento respectivamente). Los antígenos de 70 kDa fueron reconocidos por el 86 por ciento y 90 por ciento respectivamente, de los LCRs de pacientes clínica y serológicamente positivos por ELISA para NCC. Estos antígenos no fueron reconocidos por LCRs de pacientes con otras neuropatologías del SNC. Sin embargo,...

Use of delipidized antigens of Taenia solium metacestodes in IgG-ELISA for detection of neurocysticercosis.

The development of IgG-ELISA for detecting neurocysticercosis is aimed at the routine laboratory, and requires a particular antigen preparation, an acceptable number of serum samples to be tested (both homologous and heterologous) and patients with a diversity of helminthic infections to rule out cross-reactions. This study characterizes IgG-antibodies from cases of neurocysticercosis by assaying the sera against ether-delipidized antigens (5 microg/ml) prepared from metacestodes of Taenia solium. The test had a sensitivity of 90% and a specificity of 83%. IgG-antibodies from heterologous serum samples elicited a number of false positives (25/147) from six different helminthic infections, ie paragonimiasis, echinococcosis, opisthorchiasis, ascariasis, taeniasis and fascioliasis. In additional tests to detect antibody levels to these stage-related antigens, one of three serum samples from T. solium-infected cases gave negative at OD value of 0.187 while the others yielded 0.472 and 0.576. Conversely, assays of all serum samples from neurocysticercosis cases reacted against antigens from Echinococcus granulosus cystic fluid, Paragonimus heterotremus and Opisthorchis viverrini adult worms. In comparison, the antigens from these three species yielded higher mean OD values when assayed against the corresponding infected serum samples. Furthermore, neurocysticercosis cases yielded OD values that are separate and distinct from those of paragonimiasis cases.

Prevalence of anti-Taenia solium antibodies in sera from outpatients in an Andean region of Ecuador

Sera from 9,254 individuals that presented at one of three outpatient clinics in Quito, Ecuador were assayed by indirect hemagglutination for the presence of antibodies reactive with antigens from Taenia solium cysts. Immunoblot anlysis of 81 selected sera with IHA titers ranging from 0 to 1,028 showed that a titer of maior ou igual a 32 was suggestive of exposure to the parasite. Nine percent (9 por cento) of the 9,254 patients had titers of 32 or greater. Of 3,503 sera from one clinic, which included sera from food handlers undergoing yearly physicals, 390 (11 por cento) were positive. In addition, a correlation with age was seen in some, but not all, populations. In situations where age-related effects were noted, the highest incidence was seen in the youngest (0-20 years) and in the oldest (51-60 years) group. Thus, a resurgence of infection after a period of lower prevalence may be developing. Overall, this study shows that cysticercosis is relatively common and potentially a serious health problem in this region.

Comparaçäo entre os testes de eritroimunoadsorçäo por captura, imunoenzimático e hemaglutinaçäo passiva utilizados no diagnóstico da neurocisticercose / Comparison of the erythroimmunoadsorption by capture, immunoenzymatic and passive haemagglutination tests used in the diagnosis of neurocysticercosis

Foi realizada a comparaçäo entre os testes de eritroimunoadsorçäo por captura (EIAC), imunoenzimático (ELISA) e de hemaglutinaçäo passiva (HAP) utilizados no diagnóstico da neurocisticercose. Foram comparados dois testes já anteriormente utilizados na rotina diagnóstica da neurocisticercose (ELISA E HAP) e um recentemente pradonizado (EIAC) para a detecçäo de anticorpos anti-Cysticercus cellulosae. O antígeno empregado nos três testes foi o extrato salino bruto (ESB), com um rendimento de 0,1; 1 e 1micrag proteína/cavidade para os testes EIAC, ELISA e HAP, respectivamente. Quando se analisou em grupo de 58 pacientes com neurocisticercose, a sensibilidade observada foi de 98,2 porcento, 84,5 porcento e 77,2 porcento nos testes ELISA, EIAC e HAP, respectivamente, para um grupo controle de 85 indivíduos, saudáveis ou com outras encefalotipatias, mas sem neurocisticercose, a especificidade foi de 94,1 porcento, 95,3 porcento, 91,8 porcento respectivamente, nos testes. Esta ordem de escolha poderia ser obedecida na medida dos recursos disponíveis