Neurocysticercosis

[Neurocysticercosis and Lennox-Gastaut syndrome: case report]

Report of a girl with the epileptic, hydrocephalic and encephalitic form of neurocysticercosis, diagnosed by cerebrospinal fluid and computed tomography exams, during her second year of life and an evolution with multiple types of seizures, prolonged periods of intracranial hypertension due to obstruction in the ventriculoperitoneal shunt, psychomotor regression and blindness until she was 10 years old, when the Lennox-Gastaut syndrome was diagnosed. Nowadays the patient is 16 years old and presents complex partial seizures with automatism not completely controlled with clobazan and oxcarbazepine, associated to left spastic hemiparesis, universal hyperreflexia, psychomotor agitation, self-mutilation, amaurosis and severe mental retardation. The association between neurocysticercosis and Lennox-Gastaut syndrome was first described in 1973 by Frochtengarten & Scarante in a Brazilian girl with a similar clinical picture.

Improved detection of intraventricular cysticercal cysts with the use of three-dimensional constructive interference in steady state MR sequences

BACKGROUND AND PURPOSE

Before the advent of MR imaging, intraventricular cysts were difficult to diagnose noninvasively. Among the invasive procedures used were contrast ventriculography and CT ventriculography. MR imaging, with its multiplanar imaging capabilities, excellent depiction of tissue contrast, and versatile parameters, is an important tool in the assessment of intraventricular cystic lesions. We investigated the role of three-dimensional constructive interference in steady state (3D-CISS) MR sequences in the evaluation of intraventricular cysticercal cysts.

METHODS

The study group comprised 11 patients with intraventricular cysticercal cysts. MR studies included spin-echo (SE) T1-weighted, turbo-SE T2-weighted, and 3D-CISS sequences. All images were obtained on a superconducting 1.5-T MR unit. The routine and 3D-CISS sequences were reviewed and interpreted separately by two neuroradiologists.

RESULTS

All patients underwent surgery for excision of intraventricular cysticercal cysts. Eight patients had cysts in the fourth ventricle, two in the lateral ventricle, and one in the third ventricle. SE T1-weighted images showed the cystic wall in nine cases, the scolex in four, and the cystic fluid in two. Turbo-SE T2-weighted images showed the cystic wall and scolex in three and four cases, respectively. The routine sequences did not show the scolex, cystic wall, or cystic fluid together in any of the 11 patients. 3D-CISS images showed the scolex in all 11 patients and the cystic wall and cystic fluid in eight patients each. In seven of the 11 patients, 3D-CISS images showed the scolex, cystic wall, and fluid together.

CONCLUSION

The 3D-CISS sequence is more sensitive and specific than routine SE sequences in the diagnosis of intraventricular cysticercal cysts.

Clinical aspects of neurocysticercosis in children

The purpose of this report was to evaluate the clinical aspects of neurocysticercosis in children from a Brazilian region. A retrospective study of 25 children with this neuroparasitosis was performed. The diagnosis was based on clinical, cerebrospinal fluid, and neuroimaging findings. The patients were predominantly male (72%), were 1 to 11 years of age (average = 8 years, 6 months), and most resided in urban areas (68%). The more frequent manifestations were epileptic seizures (72%), headache (60%), learning disability (24%), behavioral changes (12%), psychomotor involution (8%), and intracranial hypertension (4%). The neurologic examination was normal in 80% of the patients. Twenty-two children received only symptomatic drugs. Three patients underwent treatment with cysticidal drugs, one with praziquantel and two with albendazole, with complete remission of the signs in one patient (33%) and improvement in two others (67%). Of the 25 patients, 43.4% had remission and 47.8% had improvement. We emphasize the need to consider neurocysticercosis as a differential diagnosis in children coming from endemic areas and presenting with learning disabilities, behavioral changes, and psychomotor involution. The clinical aspects in most of the children from the Botucatu region suggest a spontaneous resolution of neurocysticercosis without the need for cysticidal treatment.

Endoscopic management of cysticercal cysts within the lateral and third ventricles

OBJECT

In this report the authors review their 3-year experience with the endoscopic management of patients with hydrocephalus who harbored cysticercal cysts within the third and lateral ventricles. The management plan was to utilize an endoscopic approach to remove the cysts and to incorporate techniques useful in treating obstructive hydrocephalus. The ultimate goals were to avoid having to place a complication-prone cerebrospinal fluid shunt and to eliminate the risk of complications related to cyst degeneration.

METHODS

A retrospective analysis of 10 patients with hydrocephalus and cysticercal cysts within the third or lateral ventricles who were endoscopically managed was performed. A general description of the instrumentation and technique used for removal of the intraventricular cysts is given. At presentation, neuroimaging revealed findings suggestive of obstructive hydrocephalus in eight patients. Seven of the 10 patients treated endoscopically were spared the necessity of shunt placement. Three successful third ventriculostomies and one therapeutic septum pellucidotomy were performed. Despite frequent rupture of the cyst walls during removal of the cysts, there were no cases of ventriculitis. The endoscopic approach allowed successful removal of a cyst situated in the roof of the anterior third ventricle. One patient suffered from recurrent shunt obstructions secondary to a shunt-induced migration of cysts from the posterior fossa to the lateral ventricles.

CONCLUSIONS

The endoscopic removal of third and lateral ventricle cysticercal cysts, combined with a third ventriculostomy or septum pellucidotomy in selected cases, is an effective treatment in patients with hydrocephalus and should be considered the primary treatment for this condition.

Recent Developments in the Epidemiology, Diagnosis, Treatment, and Prevention of Neurocysticercosis

Neuroimaging studies have revealed that neurocysticercosis is a major cause of neurologic disease in most developing countries and is an emerging disease in industrialized areas. Patients with neurocysticercosis present mainly with seizures (parenchymal form) or intracranial hypertension (ventricular/subarachnoid forms). Management should be based on a thorough understanding of the pathogenesis and natural history of infection. Symptoms of active parenchymal neurocysticercosis result from the host inflammatory response to the dying metacestode form. Careful use of anticonvulsants will result in an excellent clinical outcome. The anthelminthic drugs albendazole and praziquantel are effective in killing the cysts, but their long-term effect on prognosis is unproven. Patients with obstructive hydrocephalus from ventricular cysts should be managed surgically by cerebrospinal fluid diversion or cyst removal. Treatment with antiparasitic drugs (especially albendazole) and corticosteroids may decrease the incidence of shunt failure. Current efforts at control of the disease include mass human or porcine chemotherapy in endemic zones and vaccination.

Endoscopic management of cysticercal cysts within the lateral and third ventricles

In this report the authors review their 3-year experience with the endoscopic management of patients with hydrocephalus who harbored cysticercal cysts within the third and lateral ventricles. The management plan was to utilize an endoscopic approach to remove the cysts and to incorporate techniques useful in treating obstructive hydrocephalus. The ultimate goals were to avoid having to place a complication-prone cerebrospinal fluid shunt and to eliminate the risk of complications related to cyst degeneration.

A retrospective analysis of 10 endoscopically managed patients with hydrocephalus and cysticercal cysts within the third or lateral ventricles was performed. A general description of the instrumentation and the technique used for removal of the intraventricular cysts is given. At presention, neuroimaging revealed findings suggestive of obstructive hydrocephalus in eight patients.

Seven of the 10 patients treated endoscopically were spared the necessity of shunt placement. Three successful third ventriculostomies and one therapeutic septum pellucidotomy were performed. Despite frequent rupture of the cyst walls during removal of the cyst, there were no cases of ventriculitis. The endoscopic approach successfully allowed removal of a cyst situated in the roof of the anterior third ventricle. One patient suffered from recurrent shunt obstructions secondary to a shunt-induced migration of cysts from the posterior fossa to the lateral ventricles.

The endoscopic removal of third and lateral ventricle cysticercal cysts, combined with a third ventriculostomy or septum pellucidotomy in selected cases, is an effective treatment in patients with hydrocephalus and should be considered the primary treatment for this condition.

Community prevalence study of taeniasis and cysticerosis in Bail, Indonesia

Taenia solium, a human cestode parasite endemic throughout most of South-east Asia, causes a number of public health and economic problems. The parasite is endemic in Bali due to a mix of cultural and religious practices. Immunoepidemiological investigation of three rural communities revealed a taeniasis prevalence of 0.72% (3/415). One of the three cases was due to Taenia solium, the other two to Taenia saginata. A further nine cases of Taenia infection were identified from patients from villages surrounding the chosen communities, suggesting that prevalence levels may be higher in other areas. Seroprevalence of human cysticercosis by immunoblot was 1.65% (6/363), though all cases were detected within a single community (6/115; prevalence 5.22%). Several other cases of subcutaneous cysticercosis were identified from local clinics, suggesting continued transmission of Taenia solium in the region. Other intestinal helminth parasites identified within the communities were Ascaris lumbricoides (29.9%), Trichuris trichiuria (33.9%) and hookworm (8.2%).

Lack of association between parenchymal neurocysticercosis and HLA Class I and Class II antigens

Neurocysticercosis, caused by encysted larvae of the tapeworm Taenia solium, is the most common infection of the central nervous system and a major public health problem in many countries. Prevalence in the region of Curitiba, located in the southern Brazilian State of Paraná, is one of the highest in the world. The genetics of host susceptibility to neurocysticercosis (NCC) is still obscure. To investigate if major histocompatibility complex (MHC) genes influence individual susceptibility to NCC, we performed a case-control association analysis. Fifty-two Caucasoid patients and 149 matched controls were typed for antigens of the HLA-A, B, C, DR and DQ loci. All patients had computerized tomography and clinical features compatible with parenchymal NCC. Indirect immunofluorescence of cerebrospinal fluid showed that 19 (37%) of the patients presented anti-cysticercus antibodies at titers <FONT FACE="Symbol">³</font> 1:10. Frequencies of HLA specificities in the whole group of patients and in the subgroup with antibodies in cerebrospinal fluid were compared to those of the control group. No significant difference was found. These results do not support the hypothesis of HLA gene participation in susceptibility to parenchymal neurocysticercosis.

Development of an Animal Model for Neurocysticercosis: Immune Response in the Central Nervous System Is Characterized by a Predominance of γδ T Cells

Neurocysticercosis is the most common parasitic disease of the central nervous system worldwide. It is caused by the metacestode form of the helminth Taenia solium. Study of the immune response in the human brain has been limited by the chronic progression of the disease, the influence of corticosteroid treatment, and the scarcity of patients who undergo surgical intervention. To better understand the immune response and associated pathology in neurocysticercosis, a mouse model was developed by intracranial infection of BALB/c mice with Mesocestoides corti, a cestode organism related to T. solium. The immune response reveals the presence of abundant inflammatory infiltrates appearing as early as 2 days postinfection in extraparenchymal regions. In contrast, infiltration of immune cells into parenchymal tissue is significantly delayed. There is a natural progression of innate (neutrophils and macrophages), early induced (NK cells and γδ T cells), and adaptive immune responses (αβ T cells and B cells) in infected mice. γδ T cells are the predominant T cell population. A cell-mediated Th1 pathway of cytokine expression is evident in contrast to the previously described Th2 phenotype induced in the periphery.

Solitary cysticercus granuloma of the brainstem. Report of four cases

Isolated brainstem involvement in patients who have neurocysticercosis is rare. The authors describe the clinical and radiological features of four patients with a solitary cysticercus granuloma of the brainstem and discuss their case management. In three of the patients the onset of symptoms was fairly rapid, occurring over a few days. The granuloma appeared as an enhancing lesion measuring 20 mm or less, with a ring- or disklike appearance on computerized tomography and magnetic resonance imaging. A stereotactic biopsy provided the definitive diagnosis in one patient. In two patients the granuloma resolved spontaneously with complete regression of symptoms and signs and in one patient the granuloma resolved following albendazole therapy. In all patients, outcome was excellent or good (follow-up evaluation 6 months-3 years) with only one patient having persistent paresthesias on one side of his body. Because spontaneous resolution is the rule, a conservative approach to case management, including observation, is recommended. The importance of recognizing this entity and avoiding unnecessary surgical intervention or empirical antituberculous chemotherapy is emphasized.

[Neurocysticercosis: contribution of autopsies in the consolidation of mandatory notification in Ribeiräo Preto-SP,Brazil]

Neurocysticercosis is a serious public health problem in several countries of Asia, Africa and Latin America. The objective of the present study is to present autopsy findings of neurocysticercosis in the Pathology Division of the University Hospital, Medical School of Ribeirão Preto, University of São Paulo, from 1992 to 1997. Neurocysticercosis was detected in 38 (1.5%) of 2522 autopsies. In twenty two (57.9%) of these, the diagnosis was made post-mortem, while 16 (42.1%) had a previous diagnosis of cysticercosis based on laboratory and imaging studies. Reviewing the medical records, we found that 21 patients (55.2%) were neurologically asymptomatic, while the various clinical manifestations in the others were in accordance with the literature. The high frequency of asymptomatic individuals detected only post-mortem indicates the importance of autopsies as an additional source of data to consolidate the compulsory notification of cysticercosis. Considering the results of this study, the new coefficient of prevalence of cysticercosis in Ribeirão Preto is 67 cases/100,000 inhabitants.

Central nervous system vasculitis

Central nervous system vasculitis occurs in a variety of clinical settings. Some exhibit a distinct age preference; others a tissue tropism. Most frequently encountered are giant cell arteritis (temporal arteritis) and vasculitis secondary to infections. The central nervous system may be involved in the antineutrophil cytoplasmic antibody-associated systemic vasculitides and occasionally neurologic abnormalities appear as a presenting manifestation of disease. Isolated angiitis of the central nervous system, a rare form of vasculitis that is restricted to the central nervous system, must be distinguished from other causes of central nervous system inflammation and from noninflammatory vascular disease. We are learning a great deal about the cellular mechanisms of vascular inflammation in general. Some manifestations of the clinical disease result from histologic features of the infiltrate and the size of affected vessel. However, the local consequences of inflammation, such as increased coagulation and altered vasomotor tone, as well as the systemic consequences, such as activation of the central noradrenergic systems, trigeminovascular system, and hypothalamic pituitary adrenal axis, contribute both to pathogenesis of disease and to recovery.