Epilepsy and Neurocysticercosis in Rural Bolivia: A Population‐based Survey

Abstract

Summary:Purpose: To evaluate the frequency of neurocysticercosis (NCC) in a well-defined prevalent cohort of epilepsy patients in the rural area of the Cordillera province.Methods: We carried out a two-phase door-to-door neuroepidemiologic survey in a sample of 10,124 subjects in a rural area of the Cordillera Province, Bolivia, to detect the prevalence of the most common neurologic disorders including epilepsy. A team of health workers administered a standard screening instrument for neurologic diseases; subjects found positive at the screening phase underwent a complete neurologic examination. Epilepsy patients were diagnosed according to the definition proposed by the International League Against Epilepsy (ILAE, 1993). Epilepsy patients identified this way underwent electroencephalographic recording, computed tomography (CT) scan, and serologic evaluation to detect antibodies against Taenia solium by enzyme-linked immunoelectrotransfer blot.Results: At the end of the survey, we detected 124 defined prevalent epilepsy patients. On the basis of the classification proposed by the ILAE in 1981, partial seizures were the most common type diagnosed (66 patients, 53.3%). Of the 124 patients, 105 underwent CT scan, and a serum sample was taken to detect antibodies against T. solium in 112 patients; for 97 patients, both neuroradiologic and serologic data were available. Considering radiologic, serologic, and clinical features, of these 124 patients, 34 (27.4%) fulfilled the diagnostic criteria for definitive or probable NCC proposed in 2001. Of these 34 patients 24 (70.6%) had partial seizures.Conclusions: Our data confirm a high frequency of NCC among a well-defined prevalent cohort of epilepsy patients. Key Words: Neurocysticercosis-Epilepsy-BoliviaEpidemiology.Cysticercosis is a systemic infection by the larval tissue stage of the pork tapeworm Taenia solium. Humans acquire cysticercosis by ingesting eggs of T. solium in food or water contaminated by feces of individuals who harbor the adult parasite in the small intestine, or by autoinfection (1). Although cysticercosis has a worldwide distribution, its prevalence is highest in developing countries. Neurocysticercosis (NCC), caused by infection of the central nervous system with the larval stage of T. solium, is considered the major cause of neurologic disease in developing countries of Latin America, Africa, and Asia (2). NCC has a broad spectrum of clinical manifestations, with seizures being the most frequent, and is considered one reason for the higher incidence of epilepsy in developing versus industrialized countries (3). Even if NCC is a common disease, its diagnosis remains problematic. Neuroimaging studies are usually abnormal but not pathognomonic, and current serological assays to detect antibody against T. solium have shown decreased sensitivity in patients with single or calcified lesions. In particular, enzyme-linked immunoelectrotransfer blot (EITB), considered the most practical screening tool for epidemiologic research, has demonstrated a specif...

Extraparenchymal neurocysticercosis: Demographic, clinicoradiological, and inflammatory features

“…Similar results were found in other studies [40, 41], but the explanation is not clear. The influence of these demographic variables on radiological and inflammatory features of NCC was more evident.…”

Epilepsy and Neurocysticercosis in Sub-Saharan Africa

“…In a recently conducted study, there was a trend of people with epilepsy and NCC being older and having their first seizure later compared to people with epilepsy without NCC [74]. Other studies also report that NCC is the cause of late-onset epilepsy [75][76][77][78]. A possible reason might be that older people with epilepsy are more susceptible to the infection.…”

Neurocysticercosis as a Cause of Epilepsy and Seizures in Two Community-Based Studies in a Cysticercosis-Endemic Region in Peru

“…One of the leading causes of seizures and epilepsy in developing countries is neurocysticercosis (NCC), a helminthic disease of the central nervous system [5], [7]–[9]. Trauma, genetic predisposition, other infections and social and cultural factors contribute to epilepsy prevalence worldwide [5].…”