Active neurocysticercosis, parenchymal and extraparenchymal: a study of 38 patients.

In this retrospective study we have analysed a series of 38 patients seen from 1983 to 1992 (mean follow-up, 4.5 years) with active neurocysticercosis (NCC), 23 (60.5%) with parenchymal and 15 (39.5%) with extraparenchymal NCC. Classification into these two forms of NCC was based on computed tomography and magnetic resonance imaging criteria. The enzyme-linked immunosorbent assay performed in cerebrospinal fluid, for anti-Taenia solium antibodies, was positive in 18 of 23 (78%) cases. Epilepsy and/or intracranial hypertension were the most common clinical presentation (92%). Twenty-three (60.5%) of 38 patients were treated with praziquantel and/or albendazole. In parenchymal NCC, the efficacy of medical therapy was complete in 13 of 16 (81%) and partial in 3 of 16 (19%) patients. In contrast, in all cases of extraparenchymal NCC treated with cysticidal drugs the results were disappointing. A ventriculoperitoneal shunt was performed in 9 of 13 patients with extraparenchymal NCC and hydrocephalus. Severe complications, including two deaths, associated with the natural evolution of the disease or with surgery, occurred only in extraparenchymal NCC. Therefore, we confirm the existence of the two forms of active NCC, parenchymal and extraparenchymal, which are strikingly different in clinical presentation, medical therapy response, complications, morbidity and mortality.