Neurocysticercosis: The duration of its preclinical phase relies on the parasite location.

OBJECTIVES: Neurocysticercosis (NC) is a heterogeneous disease particularly in terms of response to treatment and prognosis. Parasite localization is one of the main factors involved in this heterogeneity. In this study we aim to determine whether differences in the duration of the preclinical phase associated with parasite location, could contribute to said heterogeneity. METHODS: Ninety-nine patients were included, 24 with parasites in the parenchyma (PAR), 56 in the subarachnoid (SA) space and 19 in the ventricular system (IV). A questionnaire designed to assess exposure to classic NC risk factors 5, 10, 15, 20 and more than 20 years prior to diagnosis was applied. The results were compared between the three groups. Also, asymptomatic relatives of patients who had shared their living conditions in childhood or more recently were included and underwent brain scan and blood testing for specific antibodies. RESULTS: Over the course of their lives, exposure to risk factors decreased significantly for all patients, although the decrease was more evident in patients with parasites in the SA space (p < 0.001) compared to patients with PAR (p = 0.011) or IV cysts (p = 0.020). Five years prior to diagnosis, exposure to risk factors was significantly higher in patients with PAR or IV NC than in patients with SA NC (p = 0.04). Furthermore, individuals in close contact with PAR or IV patients in the years preceding diagnosis were more likely to have asymptomatic NC, specific antibodies in sera, particularly IgM, compared to individuals in close contact with SA patients during the same period. CONCLUSIONS: All these findings are highly suggestive of the possibility of a more recent infection of patients affected by parenchymal and ventricular NC than of patients with subarachnoid NC. Consequently, subarachnoid disease could be considered a chronic disease, which, probably contributes to the severity of the disease as well as the minimal response to medical treatment.

Neurocisticercosis extraparenquimatosa: reto terapéutico. A propósito de un caso / Extraparenchymal Neurocysticercosis: Therapeutic Challenge. About a Case

Resumen Introducción: La neurocisticercosis es una parasitosis del sistema nervioso central, causada por la ingesta de huevos de Taenia solium. Presenta una alta prevalencia en regiones de Latinoamérica, del Sudeste asiático y África subsahariana, en donde las situaciones insalubres aún prevalecen. Caso clínico: Mujer de 55 años de edad con cuadro clínico de 2 años de evolución, caracterizado por cefaleas de repetición, las cuales se han intensificado últimamente, agregándose crisis convulsivas tónico-clónicas, lo que motivó su ingreso al servicio de urgencias. Los estudios de neuroimágenes (tomografía y resonancia magnética) evidenciaron la presencia de estructuras vesiculares subaracnoideas compatibles con neurocisticercosis. Se instauró tratamiento cestocida, pero la paciente no regresó a sus citas de seguimiento durante 4 años. En su reingreso se presentó muy sintomática y requirió la administración de 8 ciclos más de tratamiento para poder erradicar los parásitos. Discusión: La gran heterogeneidad y no especificidad de los signos y síntomas dificultan el diagnóstico de neurocisticercosis. Es necesario buscar evidencias complementarias de laboratorio y de imagenología para confirmarlo. El tratamiento de esta enfermedad representa un reto para el médico, particularmente cuando el parásito se localiza afuera del parénquima encefálico, en las cisternas del espacio subaracnoideo y sistema ventricular. En menos de un tercio de estos pacientes los parásitos desaparecen con un solo ciclo de tratamiento cestocida. Conclusión: La neurocisticercosis es una enfermedad estrechamente relacionada con la pobreza, pero es prevenible. La investigación relacionada a mejorar los tratamientos sigue siendo necesaria.

Abstract Introduction: Neurocysticercosis is a parasitosis of the central nervous system, caused by the intake of eggs from taenia solium. It has a high prevalence in certain regions of Latin America, the southeast of Asia, and sub-Saharan Africa, where unhealthy situations still prevail. Clinical case: A 55-year-old woman with clinical symptoms of 2 years of evolution, such as recurrent headaches that had increased recently in addition to tonic-clonic seizures. In these conditions she was admitted to the hospital's emergency department. Neuroimaging studies (tomography and magnetic resonance imaging) showed the presence of subarachnoid vesicular structures compatible with neurocysticercosis. Therefore, a cestocidal treatment was administered but the patient did not return to her follow-up appointments for 4 years. When she finally went to her appointment, she was very symptomatic and required the administration of 8 cycles of treatment to eradicate the parasites. Discussion: The great heterogeneity and the non-specificity of the signs and symptoms difficult making a diagnosis of neurocysticercosis. Therefore, it is important to look for complementary laboratory and imaging evidence to confirm it. The treatment of neurocysticercosis represents a challenge for the physician. Particularly, when the parasite is located outside the brain parenchyma, subarachnoid cisterns and ventricular system. In less than a third of these patients the parasites disappear with a single cycle of cestocidal treatment. Conclusion: Neurocysticercosis is a disease closely related to poverty, but it is preventable. Research focused on treatments for neurocysticercosis is still necessary.