Researchers at Sanjay Gandhi Post Graduate Institute of Medical Sciences, Lucknow, India, and University of Texas Medical School at Houston performed dynamic contrast-enhanced (DCE) MRI and determined serum matrix metalloproteinase-9 (MMP-9) levels and MMP-9 gene polymorphisms in 30 subjects with a single calcified lesion of neurocysticercosis without any perilesional abnormality. These measures showed significant differences between 2 groups, each containing 15 patients, one with and one without seizures. In symptomatic subjects, serum MMP-9 levels and MMP-9 gene polymorphisms, the determinants of blood brain barrier permeability, were significantly higher compared with asymptomatic subjects with calcified cysticercus lesions and controls. There may be different degrees of perilesional inflammation with similar MRI calcified neurocysticercosis lesions in patients with or without seizures. The subject’s threshold of inflammation probably determines the occurrence of seizures. [1]

COMMENT. Albendazole and praziquantel, the two antiparasitic drugs used in treatment of neurocysticercosis, hasten radiologic resolution of cysts but may exacerbate the seizures resulting from the host inflammatory response. In patients with single inflamed brain parenchymal cysts, treatment is often withheld and is controversial. Approximately 10-20% of single cysticercal granuloma heal by calcification, and these patients are at higher risk of developing epilepsy [2]. Treatment is usually recommended for patients with nonenhancing or multiple cysticerci, and coadministration of corticosteroids for the first 2 or 3 days of therapy may decrease adverse effects. Arachnoiditis, vasculitis, or diffuse cerebral edema (cysticercal encephalitis) is treated with corticosteroids and albendazole or praziquantel. Anticonvulsant treatment is recommended until seizures are controlled for 1 to 2 years and there is radiological evidence of resolution. Calcified cysts usually require indefinite anticonvulsant therapy. Neurosurgery is indicated in patients with single intraventricular cysts and hydrocephalus. An ocular cyst should be ruled out before treatment with albendazole that may exacerbate inflammation [3].