Observaciones al microscopio electrónico de barrido del interior de un proglótido de un parásito adulto de taenia solium / Scanning electron microscopy observations of the cross-section of a taenia solium adult tapeworm

No existen, hasta el momento, imágenes que muestren la disposición de la citoarquitectura de parásitos adultos de Taenia solium, parásitos los cuales se encuentran en el intestino de portadores humanos asintomáticos. Las causas de ello podrían tener como base el que cuando se recuperan los parásitos, ellos han sufrido alteraciones debidas a la respuesta inmune de sus hospederos o bien, por el efecto que han producido en los parásitos los fármacos antihelmínticos que hayan sido usados en el tratamiento de los pacientes. Una de las alternativas que se han encontrado para la obtención de parásitos adultos, es la obtención de tenias a partir del modelo de teniosis experimental en hámsteres dorados e inmunosuprimidos y que gracias a este modelo se han podido efectuar diferentes tipos de estudios de los parásitos de esta fase infectiva. El propósito de este reporte es presentar imágenes de ultraestructura, obtenidas mediante Microscopía Electrónica de Barrido, de un corte transversal obtenido de un proglótido de una tenia recuperada de una infección experimental. Las imágenes se obtuvieron a diferentes aumentos y muestran aspectos relacionados con la superficie tegumentaria, el tegumento sincicial continuo, la capa germinal que incluye el soma de algunas células subtegumentarias y los ductos del sistema protonefridial tanto vacíos como llenos con corpúsculos calcáreos. Las imágenes ultraestructurales obtenidas muestran una forma de observación de la anatomía microscopica de los parásitos en estudio y ello contribuye a ampliar el conocimiento de los mismos en relación a aspectos de su biología celular y su fisiología.

There are no clear morphological evidences of the cytoarchitecture of intestinal adult tapeworms of Taenia solium recovered from infected humans. Parasites could be altered because of the host´s immunological response or by the direct action of drugs used for antihelminthic treatment. Experimental taeniosis in immunosuppressed golden hamsters is a useful way for recovering and studying adult parasites. The purpose of this report is to show images, taken at the ultrastructural level by Scanning Electron Microscopy (SEM), of a cross-sectioned strobilar chain from an adult tapeworm. The parasite was recovered from an experimental infection. Images were taken at several magnifications; they show the brush border tegumental surface, the syncytial tegument, the germinal layer, some cell bodies and the protonephridial system ducts: empty or filled with calcareous corpuscles. Ultrastructural images taken using SEM of T. solium adult parasites, recovered from experimental infections, could be a new way for observing the microscopic anatomy of these parasites and for increasing the knowledge of aspects related to their cellular biology and physiology.

A study of neurocysticercosis in the foothills of the Himalayas.

OBJECTIVES: The present study was planned and carried out with the aim of determining the incidence of neurocysticercosis (NCC) among patients with clinically manifested neurological disorders attending the Himalayan Institute of Medical Sciences (HIMS) hospital. METHODS: Spanning a period of 18 months, serum samples of consecutively selected patients were screened by ELISA for the presence of anti-cysticercus antibodies after obtaining a detailed history. Physical examinations were performed along with routine hematological, stool and urine tests. All patients included in the study group were also subjected to radiological investigations such as CT scan/MRI/X-ray and/or ultrasonography. RESULTS: One hundred and three new patients were selected for the study group, with a male:female ratio of 2:1. Of these, 33 (32.0%) patients were positive for Taenia solium IgG antibodies in sera. Children in the 11-20 years age group were most affected (39.4%). Only 10 patients (30.3%) were found to be positive for ova in stool, which correlated well with the presence of multiple lesions in the central nervous system (p<0.01). Solitary lesions were more common (66.7%) than multiple lesions (33.3%) on radiological diagnosis by CT scan/MRI. CONCLUSIONS: A high incidence of neurocysticercosis in the region reflects the endemic presence of T. solium and advocates the practice of better hygiene, cooking methods and water filtration procedures for the prevention of infection.