Natural history of extraparenchymal neurocysticercosis

Neurosurgical Approach to Neurocysticercosis in Adults: A Comprehensive Systematic Review of Clinical and Imaging Insights

BACKGROUND AND OBJECTIVES

Neurocysticercosis (NCC), caused by larval cysts of Taenia solium, presents a significant health challenge worldwide with diverse clinical presentations and varying management approaches. Untreated NCC can lead to increased intracranial pressure and/or hydrocephalus, with possible death. This review provides comprehensive neurosurgical insight into the heterogeneity of NCC. As there is currently no treatment algorithm for NCC, we propose a framework based on the management strategies most prevalent in the literature.

METHODS

A systematic review following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines was conducted searching PubMed, Scopus, and Embase from November 1993 to August 2023. Included articles had individual patient data on the treatments and outcomes of adult patients treated for confirmed symptomatic NCC. Relevant patient data on patient presentations, management, and outcomes and disease characteristics were collected.

RESULTS

Our analysis included 90 studies with 205 patients. Neuroimaging was diagnostic for all, with MRI being predominant (74%). Cysts were intraparenchymal (n = 69), extraparenchymal (n = 68), spinal (n = 24), and mixed distribution (n = 16). Common symptoms included seizures (39%), headache (39%), and motor weakness/paresis (28%). 67 patients presented with hydrocephalus, 30 (45%) of which received a ventriculoperitoneal shunt. NCC was most commonly treated medically with corticosteroids (56%) and albendazole (55%). Neurosurgical intervention was most commonly performed for surgical extraction of cysts (33%). Combination of medical and surgical treatment (98%, 44/45) or surgical intervention alone (98%, 40/41) was the most successful at resolving symptoms after first treatment. Resolution of symptoms with added radiographic resolution of the cyst was common with maximal treatment (n = 137, 70%).

CONCLUSION

NCC's diverse presentations and outcomes emphasize the importance of tailored therapeutic strategies. Limitations of this study include its retrospective nature and low sample sizes of individual studies. The prominence of corticosteroids, albendazole, and surgical procedures highlights their central role in NCC management, as well as the indispensable role of neurosurgeons.

Current challenges in neurocysticercosis: recent data and where we are heading

PURPOSE OF REVIEW

Neurocysticercosis (NCC) is still a significant contributor to neurological disease in vast regions of the world, and increasingly diagnosed in nonendemic countries because of travel and immigration from endemic settings. There is a need for clinicians in endemic and nonendemic regions to understand the complexities of its diagnosis and management.

RECENT FINDINGS

Recent information on the performance and use of available imaging and immunodiagnostic tools as well as antiparasitic and anti-inflammatory therapeutic regimes were assessed.

SUMMARY

Imaging and serology data should be assessed in the context of the specific type of NCC to improve diagnostic precision. In terms of therapeutic approaches, more controlled data is required on the efficacy and safety of combined antiparasitic therapy, and antiseizure and anti-inflammatory regimes should be optimized to minimize perilesional damage and reduce the risk of epilepsy.

Standardizing an Experimental Murine Model of Extraparenchymal Neurocysticercosis That Immunologically Resembles Human Infection

BACKGROUND

Neurocysticercosis (NCC) is endemic in non-developed regions of the world. Two forms of NCC have been described, for which neurological morbidity depends on the location of the lesion, which can be either within the cerebral parenchyma or in extraparenchymal spaces. The extraparenchymal form (EXP-NCC) is considered the most severe form of NCC. EXP-NCC often requires several cycles of cysticidal treatment and the concomitant use of glucocorticoids to prevent increased inflammation, which could lead to intracranial hypertension and, in rare cases, to death. Thus, the improvement of EXP-NCC treatment is greatly needed.

METHODS

An experimental murine model of EXP-NCC, as an adequate model to evaluate new therapeutic approaches, and the parameters that support it are described. EXP-NCC was established by injecting 30 Taenia crassiceps cysticerci, which are less than 0.5 mm in diameter, into the cisterna magna of male and female Wistar rats.

RESULTS

Cyst implantation and infection progression were monitored by detecting the HP10 antigen and anti-cysticercal antibodies in the serum and cerebral spinal fluid (CSF) of infected rats and by magnetic resonance imaging. Higher HP10 levels were observed in CSF than in the sera, as in the case of human EXP-NCC. Low cell recruitment levels were observed surrounding established cysticerci in histological analysis, with a modest increase in GFAP and Iba1 expression in the parenchyma of female animals. Low cellularity in CSF and low levels of C-reactive protein are consistent with a weak inflammatory response to this infection. After 150 days of infection, EXP-NCC is accompanied by reduced levels of mononuclear cell proliferation, resembling the human disease. EXP-NCC does not affect the behavior or general status of the rats.

CONCLUSIONS

This model will allow the evaluation of new approaches to control neuroinflammation and immunomodulatory treatments to restore and improve the specific anti-cysticercal immunity in EXP-NCC.

Neurocysticercosis: challenges in pediatric neurosurgery practice

PURPOSE

Neurocysticercosis (NCC) is considered a neglected infectious disease, but the most common parasitic disease of the central nervous system (CNS). Due to oral tendencies in childhood, it is hypothesized that individuals are infected around this age and develop symptoms as lately as during young adulthood. Although it is considered a benign disease, it may cause great impact in the patient's quality of life due to epilepsy, visual symptoms, and hydrocephalus, which eventually requires frequent hospitalizations. The treatment of hydrocephalus is the main challenge for neurosurgeons.

METHODS

We performed a concise review on neurocysticercosis in children and the main presentations of NCC in the neurosurgery practice and a systematic review on hydrocephalus secondary to extraparenchymal NCC.

RESULTS

Our review showed a rate of complete resolution of hydrocephalus secondary to NCC of around 80% with the first attempt of surgical treatment combined with medication therapy. Endoscopic removal of the intraventricular cysts with third ventriculostomy was the most common treatment modality. Patients previously managed with ventricular shunts are likely to have worse outcomes and complications.

CONCLUSION

Endoscopic approach is the gold standard surgical treatment for hydrocephalus secondary to neurocysticercosis.

Inflammation in neurocysticercosis: clinical relevance and impact on treatment decisions

INTRODUCTION

Neurocysticercosis is caused by the localization of Taenia solium larvae in the central nervous system. The disease remains endemic in most countries of Latin America, Asia and Africa. While major improvements have been made in its diagnosis and treatment, uncertainties persist regarding the clinical implications and treatment of the inflammatory reaction associated with the disease.

AREAS COVERED

In this review, based on PubMed searches, the authors describe the characteristics of the immune-inflammatory response in patients with neurocysticercosis, its clinical implications and the treatment currently administered. The dual role of inflammation (participating in both, the death of the parasite, and the precipitation of serious complications) is discussed. New therapeutic strategies of potential interest are presented.

EXPERT OPINION

Inflammatory reaction is the main pathogenic mechanism associated to neurocysticercosis. Its management is mainly based on corticosteroids administration. This strategy had improved prognostic of patients as it allows for the control of most of the inflammatory complications. On the other side, it might be involved in the persistence of parasites in some patients, despite cysticidal treatment, due to its immunosuppressive properties. New strategies are needed to improve therapeutical management, particularly in the severest presentations.