Abstracts

RATIONALE: Neurocysticercosis (NC) is a main health problem in developing countries. It is also becoming increasingly common in developed countries due to migration of carriers from endemic areas. The objective of this study was to investigate the relationship between CT findings - number and the viability phase of the parasites - and the seizure frequency in children with NC before and short-term after AED introduction.
METHODS: We selected 28 epileptic patients less than 16 years with probable or definitive diagnosis of NC. A semi-structured protocol was filled in for every patient considering seizure frequency before and after AED. All 28 patients had CT scan. The disease activity was classified as active, transitional and inactive, based on the viability of the parasite. Lesions on CT were grouped in different categories: number ([lt]=5, [gt] 5) and stage (active plus transitional and inactive). We used multivariate analysis of variance (MANOVA) and simple main effect and post-hoc pairwise comparison.
RESULTS: Seventeen patients were at inactive phase, six at transitional phase and five children had active lesions on CT. Regarding number of lesions, 18 patients had five or less, and 10 patients had more than five lesions. Multivariate ANOVA showed that the seizure frequency before and after AED treatment was not significantly affected by the stage of parasitic infection or the number of lesions. However, there was a significant interaction between stage of parasitic infection and number of lesions (p=0.012)in patients with more than five lesions (p=0.009)and on active-transitional stage of parasitic infection (p=0.007) when seizure frequency was considered after AED treatment.
CONCLUSIONS: We only found a significant interaction between stage of parasitic infection and number of lesions on seizure frequency after AED treatment. Patients with more than five lesions on active or transitional stages had higher seizure frequency predicting a worse short-term prognosis. The explanation may be that NC in children has a peculiar behavior. A massive infestation may occur in this age group. Eventually the cysts die and dying cysts have a much greater likelihood of being symptomatic. Dying cysts at different times may cause successive periods of exacerbation of symptoms. This is a dynamic process that may take years to resolve completely and may lead to recurrence of seizures.
Support: Dr. Ferreira received a scholarship from FAPESP.