Seroprevalencia y factores de riesgo de cisticercosis en dos comunidades rurales del norte del estado Anzoátegui, Venezuela / Seroprevalence and risk factors of cysticercosis in two rural communities in Anzoátegui state, Venezuela

Resumen Introducción. La cisticercosis es causada por las larvas de Taenia solium, las cuales se localizan principalmente en el sistema nervioso central y causan neurocisticercosis. En Venezuela se han hecho pocos estudios epidemiológicos de esta enfermedad. Objetivo. Determinar la seroprevalencia y los factores de riesgo de la cisticercosis en dos comunidades rurales del estado Anzoátegui, Venezuela. Materiales y métodos. Se hizo una encuesta para recolectar datos sobre los posibles factores de riesgo y los signos y síntomas de la enfermedad, y se tomaron 182 muestras de los habitantes de las comunidades de Boquerón y Punto Lindo. Se determinaron los anticuerpos IgG contra cisticercos de T. solium mediante ensayo inmunoenzimático (ELISA). Resultados. En Boquerón, se presentó una seroprevalencia de 3,3 %; debido al bajo número de muestras positivas no se pudo hacer el análisis estadístico. Sin embargo, las tres personas positivas tenían conocimiento de la enfermedad, antecedentes de tenencia de cerdos no confinados, consumo de carne de cerdo semicruda y cefalea frecuente. En Punto Lindo, la seroprevalencia fue de 28,9 %. No hubo diferencias estadísticamente significativas en cuanto al sexo y la edad, sin embargo, se encontró mayor frecuencia en menores de 20 años. Con respecto a los factores de riesgo y los signos y síntomas, se encontró asociación significativa con el consumo de carne de cerdo semicruda (odds ratio, OR=18; IC95% 5,78-55,9), cefalea frecuente (OR=3,6; IC95% 1,15-11,4), convulsiones (OR=18,9; IC95% 2,15-166,5) y problemas de visión (OR=5,7; IC95% 2,13-15,34). Conclusión. Los resultados demostraron que había poca transmisión de cisticercosis en Boquerón, pero mucha en Punto Lindo, sobre todo en niños, lo cual sugeriría que se trata de transmisión reciente.

Abstract Introduction: Cysticercosis is caused by Taenia solium cysticerci, which are located mainly in the central nervous system causing neurocysticercosis. In Venezuela, few epidemiological studies on this disease have been conducted. Objective: To determine the seroprevalence and risk factors for cysticercosis in two rural communities in Anzoátegui state. Material and methods: We conducted a survey to collect data on possible risk factors and signs and symptoms of the disease, and we took 182 samples in two communities, Boquerón and Punto Lindo. Detection of IgG antibodies against T. solium cysticerci was performed by ELISA. Results: Seroprevalence in Boquerón was 3.3%; due to the low number of seropositives the statistical analysis was not possible. However, the three seropositive persons had knowledge of the disease, and a history of consumption of undercooked pork meat, and presence of headache. In Punto Lindo, seroprevalence was 28.9%. There were no significant differences by sex or age; however, we found more seropositives among individuals younger than 20 years. With regard to risk factors and signs and symptoms, significant associations were found with consumption of undercooked pork (OR=18; 95% CI: 5.78 to 55.9), headaches (OR=3.6; 95% CI: 1.15 to 11.4), seizures (OR=18.9; 95% CI: 2.15 to 166.5) and visual problems (OR=5.7; 95% CI: 2.13 to 15.34). Conclusions: The results showed low transmission of cysticercosis in Boquerón, and high in Punto Lindo, where the high prevalence in children suggests recent transmission.

Evaluación de las pruebas dot blot y aglutinación de látex para el diagnóstico de cisticercosis en Perú / Assessment of dot blot tests and latex agglutination for cysticercosis diagnostic in Peru

Con el objetivo de evaluar las pruebas dot blot y aglutinación de látex para la detección de cisticercosis humana con antígeno de líquido de cisticerco de Taenia solium, se usaron 125 sueros humanos, de los cuales 60 procedían de personas con cisticercosis confirmada por Western Blot, 45 de personas con otras enfermedades parasitarias y 20 de personas aparentemente sanas. La concentración óptima del antígeno para impregnar las tiras dot blot fue de 0,01 ug/uL, y para impregnar las partículas de látex fue de 0,092 ug/uL. Para la prueba dot blot se encontró una sensibilidad del 100% y especificidad del 87,7%; para la aglutinación de látex una sensibilidad del 93,3% y especificidad del 89,2%. Ambas pruebas podrían ser de utilidad y factibles de implementar como alternativas de diagnóstico serológico en laboratorios de áreas endémicas del Perú.

In order to evaluate dot blot tests and latex agglutination for the detection of human cysticercosis with liquid antigen of Taenia solium cysticerci, 125 human sera were used, of which 60 were from people with cysticercosis confirmed by Western Blot, 45 with other parasitic diseases and 20 apparently healthy. The optimal concentration of antigen to impregnate dot blot strips was 0.01 ug/uL, and to impregnate the latex particles was 0.092 ug/uL. For the dot blot test, a sensitivity of 100% and specificity of 87.7% was found. For latex agglutination, a sensitivity of 93.3% and specificity of 89.2% was found. Both tests may be useful and feasible to implement alternatives of serological diagnosis in laboratories in endemic areas of Peru.

Comparative evaluation of different immunoassays for the detection of Taenia solium cysticercosis in swine with low parasite burden

Seven swine were experimentally infected with Taenia solium eggs and blood samples from each animal were periodically collected. At the end of the experiment (t140) the animals did not show clinical aspects of cysticercosis or parasites in tongue inspection. All animals were slaughtered and cut into thin slices in searching for cysts. The number of cysts found in each animal varied from 1 to 85. Enzyme-linked immunosorbent assay (ELISA) tests for antibody (Ab) detection and for antigen (Ag) detection were performed, which presented respectively 71 and 57 percent of positivity. By immunoblot (IB), using 18/14(T. crassiceps Ag) or lentil-lectin-purified glycoproteins from T. solium Ag (LLGP) as Ag, five (71 percent) and six (86 percent) animals were positive, respectively. The association between Ag-ELISA with any IB (18/14 or LLGP) allowed the detection of all animals at 140 days post-experimental infection (days p.e.i.). The use of IB 18/14 combined to the Ag-ELISA allowed the detection of all animals since 70 days p.e.i., and the association between IB LLGP and Ag-ELISA allowed the detection of all animals since 112 days p.e.i. While all animals could be considered healthy by conventional screening tests, the use of immunoassays for detecting Ab and Ag showed better accuracy; therefore it would be more useful than usual clinical examination for screening cysticercosis in slightly infected pigs.

El papel de los carbohidratos en la antigenicidad de las glicoproteínas del cisticerco de la Taenia solium / Hydrocarbon role in Taenia solium cysticercus glycoproteins antigenicity

La neurocisticercosis es una infección causada por el cisticerco de la T. Solium y puede confundirse con otras afecciones del sistema nervioso central. Las glicoproteínas de 12-28 kD de este parásitos son útiles para el diagnóstico serológico de la neurocisticercosis. Estas glicoproteínas contiene abundantes carbohidratos asociados vía asparagina (tipo N). Objetivo: Determinar la contribución de los carbahidratos tipo N en la antigenicidad de las glicoproteínas. Materiales y Métodos: se purificaron las glicoproteínas de 12, 16 y 18 kD de los cisticercos utilizando un gel preparativo de poliacrilamida y se sometieron a deglicosilación enzimática con PNGase F. Luego se evaluaron los cambios en antigenicidad entre las proteínas nativas y deglicosiladas por Western blot. Resultados: los antígenos deglicosilados redujeron su peso molecular a 7 kD y perdieron parte de su antigenicidad. Esta reducción fue más notoria para la proteína de 18 kD. La cual tiene mayor contenido de carbohidratos que la de 12 y 16 kD. Conclusión: estos resultados sugieren que los carbohidratos no sólo contribuyen a la antigenicidad, sino que además causan un bloqueo estérico que inhibe que el sistema inmune detecte otros epítopes no expuesto. Estos datos sugieren que la antigenicidad de las glicoproteínas de T. Solium se debe a una combinación de epítopes sacarídicos y probablemente proteicos

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

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.

Kinetics of humoral & cellular immune responses in experimental cysticercosis in pigs infected with Taenia solium.

Studies were undertaken to assess the kinetics of antibody responses, lymphocyte transformation to Taenia solium larval antigens (crude soluble extract antigen and antigen B), and T cell subpopulation in piglets following experimental infection. Cysticercosis was established in 1-2 month old piglets after feeding 5,00,000 T. solium eggs per pig. The anti-CD4 and anti-CD8 monoclonal antibodies against swine T cells were raised indigenously. It was observed that at 60 days post infection (PI) there was a significant increase (P < 0.01) in CD4+ T cells without any change in CD8+ T cells. Increased 3H-thymidine uptake was found in infected piglets at 45 days PI using both CSE and antigen B. Kinetics of antibody responses indicated significant increase (P < 0.01) at 15 days PI (with CSE antigen) and 30 days PI (with antigen B) by ELISA. This increase persisted till 90 days PI (the time up to which the animals were followed). It was also observed that the cellular mechanisms were triggered in late stage (60 days PI) as compared to humoral responses (15-30 days PI) and may persist longer as seen by both lymphocyte transformation and T cell subpopulation studies. The study suggests that in cysticercosis, both humoral and cellular mechanisms may play a role in the host defences.

Estudio de la respuesta inmune humoral en cerdos infectados con huevos y posoncósferas de taenia solium / Study on immune humoral response in pigs infected with eggs and posoncospheres of taenia solium

Due to the importance of cysticercosis in Mexico and Latin America and to the fact that in the last years another mechanism of infection for this disease has been proposed, i.e. through postoncospheres and immunosuppression of the host, we have considered relevant to perform the present work, which consisted in assessing the immune response induced by dexamethasone as well as that produced by parasites in pigs infected with T. solium eggs, or postoncosphere-infected, and in postoncosphere-infected and dexamethasone treated animals. We used 10 recently weaned pigs, three were used as controls, two of them without the drug and one with it; two were infected with T. solium eggs; five with postoncospheres receiving also dexamethasone three of them. We evaluated the humoral response against parasite antigen using indirect haemagglutination (IH) and ELISA methods. Results of the immune humoral response revealed titres of up to 1:128 in T. solium eggs infected animals, of 1:16 in postoncosphere infected animals. Absorbance titres with of 1:32 towards the end of the experiment in postoncosphere plus dexamethasone animals. Absorbance titres with Elisa confirmed these findings. Data obtained by IH show that the antibody titres of the pigs challenged with postoncospheres and postoncospheres plus dexamethasone are positive as compared to the titres obtained in the pigs infected with T. solium eggs. Results from the Elisa confirmed this finding, since, from weeks 14 to 17, the pigs became positive, behaving as those pigs that developed cysticercosis. This is revelant as it indicates that the antiposcosphere antibodies recognized antigens of T. solium larvae

Human neurocysticercosis: IgE in cerebrospinal fluid

The detection of IgE is technically difficult because of its reduced concentrations in serum, and even lower concentrations in cerebrospinal fluid (CSF). In the present investigation we studied 86 CSF samples using animmunoenzymatic method with an anti-IgE-alkaline phosphatase conjugate and a fluorigenic substrate. The samples were from three groups: A) 29 patients with neurocysticercosis (NC), B) 36 patients with different neurologic disorders (neurosyphilis, neurotuberculosis, meningitis, tumors, hemorrhage) and C) 21 discharged individuals who had been hospitalized for bacterial meningitis. The results obtained were: A) 0.05 to 3.00 IU/ml (0.76 + 0.79), B) 0.00 to 1.50 IU/ml (0.23 + 0.34) and C) 0.05 to 1.25 IU/ml (0.34 + 0.34). The present results suggest that IgE appears to play a role in the pathogeny of NC and that efforts should be made to standardize a test for the detection of specific IgE antibodies.

Hemagglutination test for the diagnosis of human neurocysticercosis: development of a stable reagent using homologous and heterologous antigens

Foi padronizado o teste de hemaglutinacao (HA) utilizando as hemacias formolizadas e taninizadas de ganso sensibilizadas com extrato salino total de C. cellulosae (HA-Cc) e liquido vesicular de Cysticercus longicollis (HA-Cl). Foram ensaiadas 61 amostras de liquido cefalorraquiano (LCR), 41 de pacientes com neurocisticercose e 20 de um grupo de controle, respectivamente, regentes e nao-regentes no teste ELISA utilizando antigenos de C. cellulosae...

Immunoperoxidase for the detection of antibodies in cerebrospinal fluid in neurocysticercosis: use of Cysticercus cellulosae and Cysticercus longicollis particles fixed on microscopy slides

A cepa ORF de Cysticercus longicollis (Cl) representa importante modelo para estudo de antigenos heterologos no imunodiagnostico da neurocisticercose (NC). Foi padronizada a tecnica de imunoperoxidase (IP) empregando suspensao antigenica particulada. Amostras de liquido cefalorraquiano (LCR) foram incubadas sobre o antigeno fixado em laminas de microscopia, o conjugado empregado foi anti-IgG-Peroxidase, a reacao enzimatica iniciou-se ao cobrirem-se as laminas com solucao cromogena (Diaminobenzidina/H2O2). Apos lavagens em agua destilada, a lamina foi corada com verde malaquita a 2 por cento em agua. De 21 LCR de pacientes com NC, 19 (90,5 por cento) foram reativos e 8 (100 por cento) LCR do grupo controle foram nao reativos. Os resultados do teste IP-Cl ensaiando 127 LCR de pacientes com suspeita de NC mostrou 89,7 por cento de concordancia com o teste ELISA empregando extrato salino de Cysticercus cellulosae (Cc) e 94,2 por cento de concordancia com o teste IP-Cc

Freqüência de anticorpos anti-Cysticercus cellulosae em indivíduos de cinco municípios da regiäo norte do Estado do Paraná - Brasil / Frequency of anti-cysticercus cellulosae antibodies in individuals from five counties in the southern region of Brazil

Realizou-se inquérito sorológico e epidemiológico para cisticercose em indivíduos de cinco municípios da regiäo Norte do Estado do Paraná, Brasil. De 2.180 indivíduos investigados através da reaçäo de imunofluorescência indireta, 69 (3,2 por cento) apresentaram títulos significativos de anticorpos anti-Cysticercus cellulosae. Os percentuais de indivíduos com títulos significativos encontrados em Sarandi (6,6 por cento) e Marialva (4,7 por cento) näo diferem estatisticamente (Z=1.319, P=0,0936), mas diferem dos percentuais encontrados em Mandaguaçu, Paiçandu e Maringá (P<0,01). Destes indivíduos, 47,9 por cento estavam na faixa etária de 21 a 49 anos e 79,4 por cento eram do sexo feminino. Foi comum o relato de queixas como "dores de cabeça" (70,6 por cento), "tonturas" (57,4 por cento) e "convulsöes" (7,4 por cento), além de história de teníase (22,1 por cento) e hábitos de ingestäo de carne crua bovina (41,2 por cento) ou suína 27,9 por cento) e carne com "canjiquinha' (25,0 por cento)

Evaluación de ELISA y contrainmunoelectroforesis en el diagnóstico de la neurocisticercosis humana en Chile / Evaluation of ELISA and counterimmunoelectrophoresis in human neurocysticercosis diagnosis in Chile

The aim of this work was to assess the diagnostic accuracy for neurocysticercosis of ELISA and counterimmunoelectrophoresis techniques, in sera and cerebrospinal fluid. 208 serum samples (47 coming from patients with confirmed cysticercosis) and 87 cerebrospinal fluid samples (27 coming from patients with confirmed cysticercosis) were analyzed. A crude and standardized extract of swine muscle cysticercus cellulosae was used as antigen. ELISA and counterimmunoelectrophoresis had a 100 percent specificity in cerebrospinal fluid, ELISA had a 85.1 percent sensitivity. Cross reactions were observed in sera of patients with confirmed hydatidosis. Thus, the high specificity of both techniques in cerebrospinal fluid is probably due to the low incidence of cerebral hydatidosis in Chile. It is concluded that for the diagnosis of neurocysteicersosis, antibodies against cysticercus cellulosae must be sought paralelly in serum and cerebrospinal fluid using ELISA and counterimmunoelectrophoresis

La prueba de ELISA en el diagnóstico de neurocisticercosis en niños / ELISA test in the diagnosis of neurocysticercosis in children

Se estudiaron 57 pacientes entre uno y 14 años de edad y se dividieron en dos grupos, uno de ellos con sospecha de neurocisticercosis consistente en 37 casos, y un grupo control de 20 pacientes similares en edad y sexo asintomáticos. A los pacientes del grupo control se les tomó muestras de sangre y liquido cefalorraquídeo (L.C.R) para realizar la prueba de ELISA, mientras que el grupo sospechoso se le tomó a todos muestra de suero; pero de L.C.R. sólo aquellos que tuvieran titulaciones iguales o mayores de 1:256. En el grupo control (I), se obtuvieron titulaciones hasta de 1:128 en suero, mientras que 19 fueron negativos en L.C.R. En el grupo sospechoso (II), 25 pacientes tubieron similares tutulaciones al grupo control y 11 las tuvieron superiores. De estos 11, seis fueron positivos en L.C.R. Se demuestra una diferencia significativa (p<0.05) en los dos grupos en lo que respecta a las titulaciones en suero; y se detectan las titulaciones sugestivas de la enfermedad. Se evidencia la baja sensibilidad de la prueba de ELISA para el diagnostico de neurocisticercosis en niños

Cisticercose suína: um estudo em áreas endêmicas no Peru / Porcine cysticercosis: a study in endemic areas from Peru

O objetivo é estudar questöes relativas à mensuraçäo da ocorrência da cisticercose suína, discutindo a obtençäo de taxas subestimadas a partir de amostras coletadas em matadouros oficiais. Realizou-se um estudo prospectivo, no qual 88 crias, mantidas em condiöes ambientais usuais, foram observadas durante 10 meses após o nascimento. Pelo método atuarial, estimou-se as probabilidades de um porco ser infectado e desenvolver a doença no primeiro, quarto e nono meses de vida. Tal estudo resultou na probabilidade de 58,8 por cento de um porco ficar doente até o final do período de observaçäo, resultado concordante com a hipótese de trabalho de que as taxas oficiais obtidas no Peru eram subestimadas. Entre os leitöes que adquiriram a doenças, 82,6 por cento foram infectados até o quarto mês de vida, indicando que a mensuraçäo da presença da cisticercose deveria ser efetuada em populaçöes suínas jovens, ao contrário do que ocorre atualmente nos matadouros do Peru

Prevalencia de anticuerpos contra cisticerco en pacientes con síntomas neurológicos

Mediante la técnica de ELISA se determinó la prevalencia de anticuerpos contra cisticerco en muestras de suero y líquido cefalorraquídeo (LCR) de 100 pacientes con síntomas neurológicos y de 100 pacientes con cuadros clínicos no neurológicos. De la población neurológica 13 por ciento presentó títulos positivos en suero y/o LCR, una escanografía sugestiva, síntomas clínicos compatibles y factores epidemiológicos favorables para la adquisición de cisticercosis. A estos pacientes se les diagnosticó neurocisticercosis. Otros siete pacientes presentaron imágenes escanográficas compatibles con procesos inflamatorios, muy probablemente causados por cisticercosis; sin embargo no se encontraron anticuerpos anticisticerco en suero o LCR. En el grupo de pacientes no neurológicos se encontraron títulos positivos contra cisticerco en el suero de dos pacientes. Estos datos evidencian la presencia e importancia de esta helmintiasis como causa de morbilidad en nuestro medio y justifican futuras investigaciones encaminadas a obtener métodos más específicos de un diagnóstico

A reaçåo imunoenzimática para cisticercose no líquido cefalorraquiano: consideraçöes sobre o limiar de reatividade / Immunoenzymatic assay for spinal fluid neurocysticercosis: cut off considerations

Um teste imunenzimático (ELISA) para neurocistercercose foi realizado em 335 amostras de líquidos cefalorraquianos (LCR), sendo 132 normais (LN), 115 com alteraçöes näo decorrentes de neurocisticercose (LA) e 88 obtidas de pacientes com neurocisticercose (LC). O limiar de reatividade (LR) foi determinado pela média aritmética das densidades ópticas (DO) das amostras LA acrescidas de 2 desvios padräo (sd). O teste ELISA apresentou sensibilidade de 97,7 por cento e especificidade de 96,4 por cento. Os valores de sensibilidade encontrados para as reaçöes de imunofluorescência indireta, fixaçäo de complemento e hemaglutinaçåo foram, respectivamente, de 80,7 por cento, 69,3 por cento e 62,5 por cento. A associaçäo do teste ELISA e a reaçäo de fixaçäo de complemento forneceu sensibilidade de 100 por cento. Näo houve correlaçäo entre as densidades ópticas do teste ELISA e os níveis de proteínas totais de amostras, tanto no grupo LA (r= -0,02), como no LC (r= -0,07).