Cisticercose: fatores relacionados a interação parasito-hospedeiro, diagnóstico e soroprevalência

Abstract

Cysticercosis is a disease characterized by the presence of the metacestoda larval form of Taenia solium in human tissues, caused by the accidental ingestion of viable eggs present in faecal material of individuais who carry the adult worm. The Central Nervous System is the most importam disease site due to the severity of symptoms, disease polymorphism and the difficulties involved with diagnosis. The disease course is determined by the immune and inflammatory mechanisms generated by the host/parasite interaction, which occurs at different degrees of complexity, resulting from the activation and migration of the oncospheres through the lumen of the small intestine and from larval implantation and survival in host tissues. The stage of development, number and localization of the cysticerci determine disease symptoms and will influence immunological and radiologic diagnosis. Defmitive diagnosis can only be established through parasite demonstration in a given specimen but technical difficulties and the invasive nature of procedures lead to presumptive diagnosis in most of the cases. Radiologic methods such as an brain computed tomography scan and magnetic resonance imaging are of limited use in developing countries due to high cost and restricted availability. The detection of antibodies against the larval form of Taenia solium is recommended for symptomatic individuais and is widely used in seroepidemiological studies. Due to the high sensitivity and specificity, the enzyme-linked immunosorbent assay and the enzymelinked immunoelectrotransfer tests are largely employed. Data from developing countries show increasing numbers of cysticercosis cases, with high frequency among imigrants from México and South Ásia. Few studies related to cysticercosis frequency have been published whereas heterogeneity of the serological tests currently used compromise an accurate estimate of cysticercosis prevalence. In developing countries, the prevalence of antibodies anti- Cysticercus cellulosae ranges from 1% to 21%. In Brazil, studies are limited to few states and most are restricted to cysticercosis active cysticercosis disease, observed in neurology centers and anatomopathological reports from general and psychiatric hospitais.