Serological tests are an important tool for the diagnosis of neurocysticercosis (NCC), the disease caused by Taenia solium metacestodes. The aim of the present research was to test the application of Taenia saginata metacestodes as an alternative antigen for use in the immunofluorescence antibody test (IFAT), enzyme-linked immunosorbent assay (ELISA), and Western blotting (WB) tests compared with the metacestodes antigen of T. solium in serum samples. The samples were obtained from 130 individuals: 20 from patients with definitive NCC, Group 1; 18 from individuals infected by Taenia sp., Group 2; 40 from individuals infected by various parasites, Group 3; and 40 from healthy individuals, Group 4. The sensitivity of IFAT, ELISA, and WB using antigen obtained from T. solium applied to the patients of Group 1 yielded results of 85, 95, and 95%, respectively, for the three tests. When the tests were conducted using T. saginata metacestodes, results were 75, 80, and 85%, respectively. The specificity of IFAT, ELISA, and WB using antigen obtained from T. solium yielded results of 94.9, 88.8, and 93.9%. When the tests were conducted using T. saginata metacestodes, results were 95.9, 88.8, and 93.6%, respectively. No statistical differences for sensitivity or specificity among the antigens were found. In conclusion, the results indicated that T. saginata metacestodes can be used as an alternative antigen for NCC diagnosis.

O presente estudo teve como objetivo levantar dados sobre a incidência de parasitos intestinais em pacientes atendidos pelo serviço público no Hospital Municipal de Cumari, Goiás. Os exames parasitológicos foram realizados entre janeiro de 2002 e dezembro de 2008, pelo método Hoffmann, Pons e Janer ou por sedimentação espontânea. Das 1.029 amostras analisadas, 373 (36,2%) apresentaram ovos ou cistos de parasitos, entre os quais foram encontradas espécies como: Giardia lamblia, Entamoeba coli, Hymenolepis nana e Strongyloides stercoralis. Giardia lamblia merece destaque por ter apresentado elevada prevalência, que se manteve constante durante os seis anos de estudos, e pela elevada incidência encontrada nas diferentes faixas etárias, em média 33,6% (n = 346). Os elevados índices de giardiose podem estar associados a provável contaminação da rede pública de abastecimento de água, visto que este protozoário resiste à ação do cloro adicionado à água tratada. Esta prevalência é semelhante aos dados registrados em outras publicações e, nestes casos, é recomendada a implementação de políticas públicas de saúde que visem ao controle destas enteroparasitoses. DESCRITORES: Giardia lamblia. Parasitoses intestinais. Serviço Público de Saúde. Goiás. INTRODUÇÃOAs enteroparasitoses constituem um grave problema de saúde pública, principalmente em países em desenvolvimento (25). No Brasil a ocorrência destes parasitos é bastante elevada, sobretudo nas populações de baixo nível socioeconômico (29). De acordo com a Organização Mundial de Saúde (36),

Hydrophobic fraction of Taenia saginata metacestodes, rather than hydrophilic fraction, contains immunodominant markers for diagnosing human neurocysticercosisFração hidrofóbica de metacestódeos de Taenia saginata, ao contrário da fração hidrofílica, contém marcadores imunodominantes para o diagnóstico de neurocisticercose humana

The aim of the present research was to test the application of Taenia saginata metacestodes as an alternative antigen for use in enzyme-linked immunosorbent assay (ELISA) and Western Blotting (WB) tests compared with the use of metacestodes antigen of Taenia solium in cerebrospinal fluid (CSF) samples. The samples were obtained from 35 patients with definitive neurocysticercosis (NCC)-group 1-and 44 patients with other neurological disorders (control)-group 2. The sensitivity and specificity of ELISA, using antigen obtained from T. solium, applied to the patients of group 1 yielded results of 100%. When the tests were conducted using T. saginata metacestodes, results were 100% and 93.2%, respectively. The 47-52-, 64-68-, and 70-kDa antigens showed high frequencies in CSF samples from patients with NCC when WB was conducted with both antigens. The results indicate that T. saginata metacestodes can be used as an alternative antigen for the diagnosis of human NCC in CSF samples.

SUMMARYA total of 354 serum samples from inhabitants who frequent the Clinical Laboratory in Catalão, Goiás, in the central-western region of Brazil, were collected from June to August, 2002. The samples were evaluated by indirect immunofluorescence antibody tests and an enzyme linked immunosorbent assay in order to detect anti-Taenia solium metacestode IgG antibodies. Reactive and inconclusive samples were tested by Western blotting (WB). Considering WB as a confirmation, the frequency of antibodies in the serum samples of the above population was 11.3% (CI 5.09 -17.51). The immunodominant bands most frequently recognized in WB were 64-68 kDa (97.5%) and 47-52 kDa (80%). The percentage of seropositivity to cysticercosis was significantly higher for individuals residing in areas without sewage systems (p < 0.0001). In conclusion, the results indicate a probable endemic situation of cysticercosis in this population. These results reinforce the urgent need for control and prevention measures to be taken by the local public health services.

Taenia saginata metacestode antigens have been constituted a useful alternative antigen for neurocysticercosis (NC) serodiagnosis, particularly due to an increasing difficulty to obtain Taenia solium homologous antigen. Cross-reactivity with Echinococcus granulosus infection occurs in homologous and heterologous antigens and could be avoided by using different purified methods. The present study evaluated antigen fractions obtained from saline extracts of T. saginata metacestodes purified by affinity chromatography with jacalin or concanavalin A (ConA) lectins to detect IgG antibodies by enzyme-linked immunosorbent assay (ELISA) and immunoblot analysis to diagnose human NC. Serum samples were collected from 142 individuals: 40 of them were diagnosed with NC, 62 presented Taenia sp. and other parasites, and 40 were apparently healthy individuals. The jacalin-and ConA-unbound fractions demonstrated sensitivity and specificity higher than those of bound fractions. Among unbound fractions, ConA demonstrated statistically higher sensitivity and specificity by ELISA (90% and 93.1%, respectively). By immunoblot assay, the 64-to 68-kDa component from the ConA-unbound fraction showed 100% sensitivity and specificity, making this component suitable for use as a specific antigen for diagnosis of NC. To our knowledge, this is the first report showing the relevance of using the unbound ConA fraction of T. saginata metacestodes to diagnose NC. In conclusion, the results obtained herein clearly demonstrate that antigenic fractions without affinity to ConA, obtained from T. saginata metacestodes, are an important source of specific peptides and are efficient in the diagnosis of NC when tested by immunoblot assay.Taenia solium is a parasite whose larvae (metacestodes) may be located in the central nervous system of humans, causing neurocysticercosis (NC). Clinical manifestations are nonspecific and vary in severity, ranging from headaches, dizziness, and occasional seizures to a very severe neurological condition with intracranial hypertension or dementia (39,40,42).The diagnosis of NC is given by the combined analysis of clinical data and neuroimaging (computerized tomography and magnetic resonance imaging) as well as immunological and epidemiological data (10). From the neuroimaging findings of NC, only the presence of cystic lesions demonstrating the scolex should be considered pathognomonic (4). In many countries where T. solium is endemic, neuroimaging methods could be inaccessible and/or too expensive for the population at risk, often rural. Under these conditions, serology may provide a viable tool for diagnosis of the infection (6,16,18,35).As NC immunodiagnosis continues to be a challenge because of the increasing difficulty in obtaining parasites from naturally infected pigs for the preparation of T. solium homologous antigen (33), alternative antigens, including heterologous antigens from Taenia saginata, have also been used with satisfactory results to diagnose human NC (29,31,32). T. saginata cysticerci in the cysti...

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Objetivo: realizar análises parasitológicas em amostras de solo provenientes da represa da Bica situada no município de Catalão-GO. Métodos: a área do entorno da represa foi dividida em cinco parcelas, sendo realizadas coletas em dois pontos de cada parcela, superior e inferior. Foram realizadas quatro coletas em dias alternados, totalizando 40 amostras de, aproximadamente, 50g da camada superficial do solo, com profundidade máxima de cinco centímetros. As amostras foram processadas no Setor de Diagnóstico Parasitológico do Laboratório de Biologia Molecular da Universidade Federal de Catalão (UFCAT). Para as análises parasitológicas, foram utilizados cinco métodos encontrados na literatura, Rugai, Willis, Sedimentação espontânea, Ritchie e Ritchie modificado. Resultados: pelo método de Rugai, foi possível detectar larvas rabditoides do gênero Ancylostoma e Strongyloides. Utilizando o método de Ritchie modificado, foram encontrados ovos de Ascaris lumbricoidese Ancylostoma sp. Conclusão: a presença de formas evolutivas no solo da represa indica contaminação por dejetos animais e humanos, favorecendo o estabelecimento de ciclos biológicos das espécies encontradas e de outras diferentes zoonoses. Os dados obtidos demonstram a importância de sensibilizar a população de medidas de promoção da saúde, além de ações preventivas e programas de educação em saúde.