Background: Conflicting reports have caused controversy on whether cysticidal drugs modify the natural course of neurocysticercosis.
Purpose: To perform a meta-analysis of randomized trials assessing the effect of cysticidal drugs on neuroimaging and clinical outcomes of patients with neurocysticercosis.
Data sources: Search of MEDLINE, Cochrane Database of Systematic Reviews, and Literatura Latino-Americana y del Caribe en Ciencias de la Salud (LILACS) between 1979 and 2005. There were no language restrictions.
Study selection: Randomized trials of cysticidal drug therapy for neurocysticercosis that met predefined criteria designed to allow characterization of the disease and objective evaluation of therapy. The authors independently reviewed articles. Abstracted data included study design, number of randomly assigned patients and withdrawals, intervention, adverse events, timing of neuroimaging studies, and outcomes.
Data synthesis: Eleven studies met the inclusion criteria. Six trials randomly assigned 464 patients with cystic lesions (vesicular cysticerci), and 5 trials randomly assigned 478 patients with enhancing lesions (colloidal cysticerci). Parasites were located in the brain parenchyma or subarachnoid space at the convexity of the cerebral hemispheres. Cysticidal drug therapy was associated with complete resolution of cystic lesions (44% vs. 19%; P = 0.025). Trials on enhancing lesions showed a trend toward lesion resolution favoring the use of cysticidal drugs (72% vs. 63%; P = 0.38) that became statistically significant when an outlier trial was excluded from the analysis (69% vs. 55%; P = 0.006). Risk for seizure recurrence was lower after cysticidal treatment in patients with enhancing lesions (14% vs. 37%; P < 0.001). The single trial evaluating the frequency of seizures in patients with cystic lesions showed a 67% reduction in the rate of generalized seizures with treatment (P = 0.006).
Limitations: Not all studies focused on the control of seizures as an outcome.
Conclusions: Cysticidal drug therapy results in better resolution of colloidal and vesicular cysticerci, lower risk for recurrence of seizures in patients with colloidal cysticerci, and a reduction in the rate of generalized seizures in patients with vesicular cysticerci.