Association between epilepsy and cysticercosis and toxocariasis: a population-based case-control study in a slum in India.

PURPOSE

To assess the association between epilepsy and exposure to the parasites, Toxocara canis and Taenia solium in a slum-community in India.

METHODS

A door-to-door survey to determine the prevalence of epilepsy was carried out by trained field workers. For every case, one age- and gender-matched control was selected from the same community. Serologic evaluation was carried out to detect antibodies against T. canis and T. solium.

KEY FINDINGS

The crude prevalence of active epilepsy was 7.2 per 1,000. We enrolled 114 people with active epilepsy and 114 controls. The prevalence of antibodies to T. canis was similar in people with active epilepsy (4.7%; 5 of 106 people) and in controls (5.7%; 6 of 106 people). The prevalence of antibodies to T. solium was 25.5% (27 of 106) in people with active epilepsy, significantly higher than in controls (12.3%; 13 of 106 cases; p = 0.02). Adjusted conditional (fixed-effects) logistic regression estimated an odds ratio of 2.8 (95% confidence interval 1.2-6.8) for detection of T. solium antibodies. Nineteen people with active epilepsy demonstrated evidence of neurocysticercosis (NCC) on magnetic resonance imaging (MRI), including 7 (36.5%) with solitary cysticercus granuloma.

SIGNIFICANCE

Our findings do not support an association between epilepsy and exposure to T. canis in the community studied. A significant association between T. solium exposure and epilepsy was observed. Of those with active epilepsy and evidence of NCC on MRI, a large proportion demonstrated solitary cysticercus granuloma.