Neurocysticercosis in Radiographically Imaged Seizure Patients in U.S. Emergency Departments

Samuel Ong, David A. Talan, Gregory J. Moran, William Mower, Michael Newdow, Victor C.W. Tsang, Robert W. Pinner, and the EMERGEncy ID NET Study Group

Disclosures

Emerging Infectious Diseases. 2002;8(6) 

In This Article

Materials and Methods

This study was a prospective case series of patients who visited any of a network of 11 geographically diverse, university-affiliated, urban emergency departments (EMERGEncy ID NET) from July 1996 to September 1998. The approximate total annual visit census of these emergency departments is 900,000. Institutional review board approval for the study was obtained at all sites. A more detailed description of EMERGEncy ID NET, including its administration and the processes of data transfer and compilation, has been published[14].

Emergency department patients >5 years of age were enrolled in the study if they had a known or suspected seizure and had undergone neuroimaging, either computed tomography scanning (CT) or magnetic resonance imaging (MRI). Patients <5 years of age were excluded to avoid enrolling a potentially large number of patients with febrile seizures. The treating physician recorded demographic and clinical data including age, sex, race, immigrant status, foreign travel, prior seizure history, seizure type, CT and MRI findings, presumptive diagnosis, and disposition.

When blood was drawn from a patient as part of the evaluation, an additional tube was obtained for this study. Serum specimens from 890 of the 1,801 patients enrolled were sent to the Centers for Disease Control and Prevention so that serologic testing for cysticercosis could be performed. Serum samples were tested by enzyme-linked immunoelectrotransfer blot for Taenia solium-specific antibodies, as described[15,16]. Briefly, this assay uses seven purified glycoprotein antigens from larval cysts of T. solium, namely, GP50, GP42-39, GP24, GP21, GP18, GP14, and GP13, where the prefix GP stands for glycoprotein and the number indicates the molecular mass in kilodaltons. These antigens are used in an immunoblot format to detect infection-specific antibodies. Reactions to at least one antigen band are considered positive[15,16].

On the basis of a classification scheme proposed by Del Brutto[17], our case definition for neurocysticercosis required either 1) CT scan finding(s) characteristic of neurocysticercosis (i.e., multiple calcifications or multiple cystic lesions) with or without a positive serologic test, or 2) CT scan finding(s) consistent with neurocysticercosis (i.e., a single cystic, calcified, or hypodense lesion) and a positive serologic test. Radiologists at each site read CT scans without regard for or knowledge of the study. Study coordinators at each site then abstracted the absence or presence of findings relevant to the study from the radiology reports. Simple descriptive statistics were used to summarize the clinical features of patients with and without neurocysticercosis. Relative risk ratios (RRs) and their corresponding 95% confidence intervals (CIs) were determined by Fisher's exact test.

Comments

3090D553-9492-4563-8681-AD288FA52ACE
Comments on Medscape are moderated and should be professional in tone and on topic. You must declare any conflicts of interest related to your comments and responses. Please see our Commenting Guide for further information. We reserve the right to remove posts at our sole discretion.
Post as:

processing....