Workshop Report (2009)

A closed workshop on “Neurocysticercosis (NCC) and Epilepsy” was held in Tumbes, Peru, with support from the American Epilepsy Society (AES), the Universidad Peruana Cayetano Heredia, and the University of Western Ontario. The aim of the workshop was to develop the foundations for an international collaborative research network on this subject. The Neurocysticercosis and Epilepsy Research Network (NERN) will comprise a group of researchers with expertise in diverse related fields aiming to foster collaborative research in all aspects of epilepsy related to NCC. The ultimate goal is to better understand the epilepsy caused by NCC; its basic molecular and genetic mechanisms; as well as the medical, surgical, cognitive, and psychosocial aspects. Epilepsy is a neurologic disorder with a worldwide distribution. Neurocysticercosis (NCC) is the most common cause of seizures in developing countries, where it accounts for up to 30% of all seizures (Medina et al., 1990; Garcia et al., 1993; Medina et al., 2005; Rajshekhar et al., 2006). Several mechanisms have been implicated in seizure development in this disease. These mechanistic explanations focus mostly on the site in the nervous system in which the parasitic larvae are located; on whether or not the larvae are alive, degenerating, or dead/calcified; and on the inflammatory and scarring processes associated with parasite death and degeneration. Neurocysticercosis is unique because it is the only infection or process where large numbers of normal persons are commonly infected with a seizure-causing agent. Therefore, properly designed studies of affected populations can be used to answer fundamental questions about the genesis and treatment of epilepsy. Other reasons that NCC may serve as a suitable model to learn about human epilepsy include (but are not restricted to): (1) the high prevalence of NCC in endemic areas, potentially allowing investigators to evaluate large series of patients; (2) the defined localization of the NCC lesions; (3) the existence of symptomatic and asymptomatic NCC cases; (4) the overall good prognosis of patients with single degenerating lesions (Rajshekhar & Jeyaseelan, 2004) or a few intraparenchymal cysts; (5) the feasibility of intervening with specific antiparasitic drugs; (6) the chronic nature of residual brain calcifications; and (7) the presence of NCC in the United States and other industrialized countries, owing to increased travel and immigration. A network of researchers in epilepsy and NCC who collaborate to collectively design and implement studies is essential to enable future collaborative multicenter research efforts and allow the pursuit of high quality and sustainable research in epilepsy and NCC. The proposed network should synergistically encompass the availability of highly qualified groups in each specific area, to allow sharing of experiences and knowledge between its members, to encourage appropriate use of resources, and to support the potential for community-based studies. The concept of a network is not novel and has yielded spectacular results in other areas of research (Cook et al., 2002; Whiting et al., 2002). The broad range of research questions involving epilepsy and NCC requires different study designs. As an initial collaborative project, the NERN will focus on the description and definition of the phenotype and evolution (clinical and electrophysiologic) of NCC-associated seizures and epilepsy. This project will, in turn, lead to basic mechanistic studies, such as brain plasticity on the molecular, cellular, and circuit levels in response to the NCC cysts, as evidenced by modern brain-imaging methods, and human large-scale genome-wide association studies that define seizure susceptibility genes that contribute to the epilepsy phenotype of NCC. The study of these issues in population- and hospital-based populations of individuals with NCC (and appropriate controls) will include not only history and findings on physical examination, but also electroencephalography (EEG), imaging, and serology data, and procedures for systematic collection and storage of serum for immunodiagnostics and proteomics and lymphoblastoid cells for DNA analysis. A lead institutional review board (IRB) protocol in a developing country and one in an industrialized country will be chosen to ensure human subject protection while avoiding all the problems related to multiple reviews. The NERN group continues to welcome new ideas, as it has done in our recent meeting (Table 1). The network approach would allow the review of study protocols proposed by the members, to evaluate their feasibility and prioritize research efforts, moving forward the more feasible ideas so as to increase the likelihood of success. We confirm that we have read the Journal’s position on issues involved in ethical publication and affirm that this report is consistent with those guidelines. Conflict of interest: None of the authors have any conflict of interest to disclose.