Neurocysticercosis: new thoughts on controversial issues

This review comments on the recent advances in the understanding of the controversial aspects of neurocysticercosis (NCC).

The number of autochthonous cases of NCC in nonendemic countries has increased during the last few years: it is likely that the migration of Taenia carriers from endemic areas is responsible for the increased prevalence of locally acquired NCC in these regions. NCC is mostly acquired from person to person, and the old theories crediting the environment as the main source of human infection with Taenia solium eggs must be abandoned. There is growing evidence suggesting that cysticercus granulomas (one of the most common forms of presentation of NCC) represent fresh infections and not old infections resulting from spontaneous destruction of viable cysticerci. Calcifications, often seen as inactive lesions producing no symptoms, are responsible for a sizable proportion of NCC-related seizures or headache. It is likely that exposure of parasitic antigens to the host's immune system is the cause of these manifestations.

During the last few years, there has been an increased knowledge on the controversial aspects of NCC, including epidemiology, mechanisms of disease acquisition, the natural involution of lesions in the brain parenchyma, and the role of calcifications as responsible for symptom occurrence.