RESUMO
Diagnosis of neurocysticercosis (NCC) can be a challenge. Clinical manifestations are non-specific, most neuroimaging findings are non-pathognomonic, and some serologic tests have low sensitivity or specificity. A set of diagnostic criteria was proposed in 2001 to avoid the over diagnosis of NCC that occurs in epidemiologic surveys, and to help clinicians evaluating patients with suspected NCC. The set included four stratified categories of criteria, including: (1) absolute: histological demonstration of cysticerci, cystic lesions showing the scolex on neuroimaging studies, and direct visualization of subretinal parasites by fundoscopic examination; (2) major: lesions highly suggestive of NCC on neuroimaging studies, positive serum enzyme-linked immunoelectrotransfer blot (EITB) for the detection of anticysticercal antibodies, resolution of intracranial cystic lesions after cysticidal drug therapy, and spontaneous resolution of single enhancing lesions; (3) minor: lesions compatible with NCC on neuroimaging studies, suggestive clinical manifestations, positive cerebrospinal fluid (CSF) ELISA for detection of anticysticercal antibodies or cysticercal antigens, and cysticercosis outside the nervous system; and (4) epidemiological: evidence of a household contact with Taenia solium infection, individuals coming from or living in cysticercosis endemic areas, and history of travel to disease-endemic areas. Interpretation of these criteria permits two degrees of diagnostic certainty: (1) definitive diagnosis, in patients who have one absolute criterion or in those who have two major plus one minor and one epidemiological criteria; and (2) probable diagnosis, in patients who have one major plus two minor criteria, in those who have one major plus one minor and one epidemiological criteria, and in those who have three minor plus one epidemiological criteria. After 10 years of usage, this set has been proved useful in both, field studies, and hospital settings. Recent advances in neuroimaging and immune diagnostic methods have enhanced its accuracy for the diagnosis of NCC.
Assuntos
Técnicas de Laboratório Clínico/métodos , Medicina Clínica/métodos , Neurocisticercose/diagnóstico , Neuroimagem/métodos , Taenia solium/isolamento & purificação , Animais , Anti-Helmínticos/administração & dosagem , Anticorpos Anti-Helmínticos/líquido cefalorraquidiano , Antígenos de Helmintos/líquido cefalorraquidiano , Análise por Conglomerados , Humanos , Neurocisticercose/parasitologia , Neurocisticercose/patologia , Taenia solium/imunologia , Resultado do TratamentoRESUMO
The pathogenesis of neuroschistosomiasis is largely unknown. Available evidence suggests that it depends on the presence of parasite eggs in the nervous tissue and on the host's immune response. We investigated the presence of immune complexes (ICs) in the cerebrospinal fluid (CSF) of four patients with spinal cord schistosomiasis (SCS), and performed their characterization. ICs containing soluble egg antigen of Schistosoma mansoni (SEA) were found in the CSF of all the SCS patients. To our knowledge, this is the first evidence of ICs containing schistosomal antigens in the CSF of patients with SCS. Further studies are necessary to confirm our findings and investigate the possible roles of ICs in the pathogenesis of this disease.
Assuntos
Complexo Antígeno-Anticorpo/líquido cefalorraquidiano , Antígenos de Helmintos/líquido cefalorraquidiano , Neuroesquistossomose/líquido cefalorraquidiano , Esquistossomose mansoni/líquido cefalorraquidiano , Doenças da Medula Espinal/líquido cefalorraquidiano , Complexo Antígeno-Anticorpo/imunologia , Antígenos de Helmintos/imunologia , Western Blotting , Eletroforese em Gel de Poliacrilamida , Humanos , Neuroesquistossomose/imunologia , Esquistossomose mansoni/imunologia , Doenças da Medula Espinal/imunologiaRESUMO
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.
Assuntos
Antígenos de Helmintos/líquido cefalorraquidiano , Neurocisticercose/diagnóstico , Taenia/imunologia , Adulto , Animais , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Neurocisticercose/líquido cefalorraquidiano , Neurocisticercose/patologia , Adulto JovemRESUMO
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.
Assuntos
Adulto , Animais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem , Antígenos de Helmintos/líquido cefalorraquidiano , Neurocisticercose/diagnóstico , Taenia/imunologia , Ensaio de Imunoadsorção Enzimática , Imageamento por Ressonância Magnética , Neurocisticercose/líquido cefalorraquidiano , Neurocisticercose/patologia , Adulto JovemRESUMO
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.
Assuntos
Anticorpos Anti-Helmínticos/sangue , Anticorpos Anti-Helmínticos/líquido cefalorraquidiano , Antígenos de Helmintos/sangue , Antígenos de Helmintos/líquido cefalorraquidiano , Neurocisticercose/imunologia , Taenia solium/imunologia , Teníase/imunologia , Adulto , Animais , Antígenos de Helmintos/imunologia , Ensaio de Imunoadsorção Enzimática/métodos , Epilepsia/epidemiologia , Epilepsia/parasitologia , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Neurocisticercose/sangue , Neurocisticercose/complicações , Neurocisticercose/patologia , Sensibilidade e Especificidade , Teníase/sangue , Teníase/patologiaRESUMO
Human neurocysticercosis (NC) is caused by Taenia solium larvae lodged in the central nervous system. This disease is usually diagnosed by radiology but the results are not always clear-cut and so immunological assays are often also used. A semi-nested PCR, based on the non-coding HDP2 sequence of T. saginata, has now been developed for detecting DNA from T. solium cysticerci and confirming NC. This PCR, which amplifies a 171-bp T. solium product, allowed the specific detection of just 174 attograms of T. solium DNA. The efficacy of the PCR was tested using cerebrospinal fluid (CSF) from neurological patients, including 46 confirmed Mexican cases of NC and 32 patients from non-endemic Spain. Eighteen of the confirmed cases [including 10 (71%) of the 14 with vesicular extraparenchymal cysticerci and four (17%) of the 24 with damaged cysticerci] and two (33%) of the six patients with 'uncertain' diagnosis (in whom a diagnosis of NC could not be established by radiological and immunological studies) were found PCR-positive. The 36 patients known to have neurological problems other than NC were found PCR-negative. The HDP2 PCR offers a new tool in the diagnosis of NC and in exploring the pathogenesis of this serious disease.
Assuntos
Anticorpos Anti-Helmínticos/líquido cefalorraquidiano , Antígenos de Helmintos/líquido cefalorraquidiano , DNA de Helmintos/líquido cefalorraquidiano , Neurocisticercose/líquido cefalorraquidiano , Taenia solium/genética , Animais , Feminino , Humanos , Masculino , Neurocisticercose/diagnóstico , Reação em Cadeia da Polimerase/métodos , Sensibilidade e EspecificidadeRESUMO
Chronic meningitism is a less frequent manifestation of neurocysticercosis caused by Taenia solium cysticerci. In the present study we used Co-agglutination (Co-A), a simple and rapid slide agglutination test to detect specific Cysticercus antigen in the 67 cerebrospinal fluid (CSF) samples from patients with chronic meningitis of unknown etiology. The results were compared with that of ELISA for detection of antibodies. Among these samples four (5.97%) were positive for Cysticercus antigen by Co-A test and six (8.95%) were positive for antibodies by ELISA. Two samples were positive by both Co-A and ELISA, two were positive only by Co-A and four were positive only by ELISA. In the present study, although Cysticercus antigen and antibodies were present in CSF samples from eight (11.94%) patients, we cannot affirm that all the cases of chronic meningitis are due to cysticercosis, but for any case of chronic meningitis of unknown origin, it would be useful to consider the possibility of cysticercal meningitis.
Assuntos
Anticorpos Anti-Helmínticos/líquido cefalorraquidiano , Antígenos de Helmintos/líquido cefalorraquidiano , Meningite/parasitologia , Neurocisticercose/diagnóstico , Testes de Aglutinação , Animais , Doença Crônica , Ensaio de Imunoadsorção Enzimática , Humanos , Meningite/líquido cefalorraquidiano , Meningite/imunologia , Neurocisticercose/complicações , Neurocisticercose/imunologiaRESUMO
Chronic meningitism is a less frequent manifestation of neurocysticercosis caused by Taenia solium cysticerci. In the present study we used Co-agglutination (Co-A), a simple and rapid slide agglutination test to detect specific Cysticercus antigen in the 67 cerebrospinal fluid (CSF) samples from patients with chronic meningitis of unknown etiology. The results were compared with that of ELISA for detection of antibodies. Among these samples four (5.97 percent) were positive for Cysticercus antigen by Co-A test and six (8.95 percent) were positive for antibodies by ELISA. Two samples were positive by both Co-A and ELISA, two were positive only by Co-A and four were positive only by ELISA. In the present study, although Cysticercus antigen and antibodies were present in CSF samples from eight (11.94 percent) patients, we cannot affirm that all the cases of chronic meningitis are due to cysticercosis, but for any case of chronic meningitis of unknown origin, it would be useful to consider the possibility of cysticercal meningitis.
Meningite crônica é manifestação pouco freqüente de neurocisticercose causada por cisticerco de Taenia solium. No presente estudo utilizamos co-aglutinação (Co-A) um teste simples e rápido de aglutinação para detectar antígeno específico de Cysticercus nas 67 amostras de fluido cerebrospinal (CSF) de pacientes com meningite crônica de etiologia desconhecida. Os resultados foram comparados com os de ELISA para detecção de anticorpos. Dentre estas amostras quatro (5,97 por cento) foram positivas para antígenos de Cysticercus pelo teste Co-A e seis (8,95 por cento) foram positivas para anticorpos por ELISA. Duas amostras foram positivas por ambos Co-A e ELISA, duas foram positivas somente por Co-A e quatro foram positivas somente por ELISA. No presente estudo embora antígenos e anticorpos de Cysticercus estivessem presentes nas amostras de CSF de oito pacientes (11,94 por cento), não podemos afirmar que todos os casos de meningite crônica sejam devidos à cisticercose, mas para qualquer caso de meningite crônica de origem desconhecida seria útil considerar a possibilidade de meningite por cisticerco.
Assuntos
Animais , Humanos , Anticorpos Anti-Helmínticos/líquido cefalorraquidiano , Antígenos de Helmintos/líquido cefalorraquidiano , Meningite/parasitologia , Neurocisticercose/diagnóstico , Testes de Aglutinação , Doença Crônica , Ensaio de Imunoadsorção Enzimática , Meningite/líquido cefalorraquidiano , Meningite/imunologia , Neurocisticercose/complicações , Neurocisticercose/imunologiaRESUMO
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.
Assuntos
Humanos , Animais , Anticorpos Anti-Helmínticos , Antígenos de Helmintos/líquido cefalorraquidiano , Imunoglobulina G/líquido cefalorraquidiano , Neurocisticercose/diagnóstico , Taenia/imunologia , Estudos de Casos e Controles , Ensaio de Imunoadsorção Enzimática , Neurocisticercose/líquido cefalorraquidiano , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Taenia solium/imunologiaRESUMO
Neurocysticercosis is the most frequent parasitic infection of the CNS and the main cause of acquired epilepsy worldwide. Seizures are the most common symptoms of the disease, together with headache, involuntary movements, psychosis and a global mental deterioration. Absolute diagnostic criteria include the identification of cysticerci, with scolex, in the brain by MRI imaging. We demonstrate here, for the first time, that T. solium DNA is present in the cerebrospinal fluid of patients. The PCR amplification of the parasite DNA in the CSF enabled the correct identification of 29/30 cases (96.7 %). The PCR diagnosis of parasite DNA in the CSF may be a strong support for the diagnosis of neurocysticercosis.