Pediatric neurocysticercosis: current challenges and future prospects

Abstract

Neurocysticercosis (NCC) is an acquired infection of the nervous system caused by encysted larvae of Taenia solium. It is a major cause of epilepsy in the tropics and the commonest cause of focal seizures in North Indian children. T. solium teniasis-cysticercosis is considered a parasitic "Neglected Tropical Diseases" endemic throughout Southeast Asia. NCC in children has pleomorphic manifestations depending on the location, number and viability of the cysts, and host response. Even with advancing knowledge of the disease manifestations, many aspects related to diagnosis and treatment, particularly in children, still remain controversial and pose challenges to clinical practice. There is no gold standard test to diagnose NCC and the management recommendations are still emerging. This review provides an overview of diagnosis of NCC in children and its management with special focus on current challenges and future prospects.

Keywords: children; epilepsy; neurocysticercosis; pigs; ring enhancing lesions.

Figure 1

Life cycle of NCC. Notes: The life cycle of Taenia solium (adult tapeworm) involves two hosts: humans and pigs. Humans are the definitive hosts and acquire intestinal infection (teniasis) from pigs, the intermediate hosts, by ingestion of undercooked pork infected with live cysticerci (encysted larvae). Humans acquire cysticercosis via consumption of food or water contaminated with T. solium eggs or by autoinfection. Neurocysticercosis (NCC) results when the larval stages lodge in the brain.

Figure 2

Brain CT scan. Notes: Contrast-enhanced axial section showing a single, small (<20 mm), hypodensity lesion with (A) ring and (B) disc enhancement, termed as single small enhancing computed tomographic lesion (SSECTL) representing a degenerating cyst with associated mild-to-moderate perilesional edema and bright, hyperdense, eccentric scolex pathognomonic for NCC. (C) Small calcified nodule with mild perilesional edema. Abbreviations: CT, computed tomography; NCC, neurocysticercosis.

Figure 3

Brain MRI scans. Notes: (A) Noncontrast axial T1-weighted scan showing small, circular cyst with cerebrospinal-like fluid and a small eccentric scolex seen as intramural nodule, isointense rim suggestive of cyst wall, and hypointense areas surrounding the cyst suggestive of perilesional edema. (B) T2-weighted axial scan showing the same cyst with cerebrospinal-isointense fluid, intramural nodule, hypointense rim suggestive of cyst wall, and hyperintense perilesional edema. (C) FLAIR axial section showing the same hypointense cyst with hyperintense scolex, thin cyst wall, and hyperintense perilesional edema. The presence of scolex is pathognomonic of neurocysticercosis. Abbreviations: MRI, magnetic resonance imaging; FLAIR, fluid-attenuated inversion recovery.