Etiology and management of single small CT lesions in patients with seizures: understanding a controversy

Epilepsy Due to Solitary Calcified Cysticercus Granuloma

The calcified stage of the neurocysticercosis (NCC) is the common cause of acquired epilepsy in low and middle income countries in people aged > 20 years. Approximately 30% of adult onset seizures and epilepsy are attributable to NCC. In India and some of the Latin American countries, epilepsy due to solitary calcified NCC is the common adult onset epilepsy. The current evidence suggests that the calcified cysticercus granuloma is probably the epileptogenic focus. The mechanisms involved in the epileptogenic process are not well understood; Focal-onset seizures with or without impaired awareness are the common seizure type. Focal-onset seizure can evolve to bilateral tonic-clonic seizure. Seizure outcome with anti-seizure medication, most often with monotherapy, is very good. The seizure disorders associated with various stages of NCC can be preventable.

Complex neurocysticercosis lesions on imaging: Explained through correlative histomorphology

OBJECTIVES

Neurocysticercosis, the commonest neuro-parasite, sometimes presents as complex ring enhancing lesion causing diagnostic dilemma. We aim to establish radio-histo-morphological equivalents of early events in degeneration of the parasite to explain such imaging phenotypes.

METHODS

We compared patterns of degeneration in 23 randomly selected complex NCC on MRI with histo-morphology in 30 cysts obtained from an unrelated post mortem brain.

RESULTS

The anatomy of the parasite and the degenerative patterns of the scolex (hydropic changes, calcification, evagination, and fragmentation) and the cyst wall (undulation, accessory loculi, and frank disruption) were well demonstrated on both. The intact scolex remarkably resembled head of intestinal Taenia. The complex lesions were conglomeration of multiple communicating cysts with a single parent cyst and multiple daughter cysts. The parent cysts contained a solitary variably degenerated scolex, had thicker walls and associated chronic inflammation. The remaining cysts of the lesion complex contained no scolex, had poorly organized walls, turbid contents, and florid perilesional enhancement with leakage of contrast. Three lesions assumed a multi-cystic pseudo-tumorous pattern, of which two resolved into solitary calcific remnants on follow up.

CONCLUSION

Complex lesion in NCC result from degeneration of solitary parasite with perilesional gliosis, surrounded by multiple non-larval daughter cysts inciting acute intra and perilesional inflammation due to enhanced antigenic challenge. Possibly, attempted abortive asexual reproduction by the cellulose cyst as a preterminal event results in a "limited Racemose like transition." Correct interpretation has diagnostic and therapeutic implications as active lesions and their fibrocalcific residue may have greater epileptogenic potential.

Imaging correlates of serum enzyme-linked immunoelectrotransfer blot (EITB) positivity in patients with parenchymal neurocysticercosis: results from 521 patients

BACKGROUND

The presence of perilesional edema among patients with parenchymal neurocysticercosis (pNCC) of various lesion subtypes has not been correlated with results of serum enzyme-linked immunotransfer blot (EITB) for cysticercal antibodies.

METHODS

In total, 521 patients with pNCC were classified into solitary cysticercus granuloma (SCG), multiple lesions, at least one of which was an enhancing granuloma (GMNCC), solitary calcified cysticercal lesion (SCC) and multiple calcified cysticercal lesions (CMNCC). The proportion of EITB positivity among each lesion subtype and its association with perilesional edema were determined.

RESULTS

There were significantly higher positive EITB results in patients with GMNCC (90/111, 81.1%) compared with other lesion types. Perilesional edema was associated with positive EITB in patients with CMNCC. On univariate analysis, perilesional edema and GMNCC were associated with EITB positivity. On multivariate analysis, only GMNCC (OR 7.5; 95% CI 3.5 to 16.2) was significantly associated with EITB positivity.

CONCLUSIONS

In patients with pNCC, the presence of perilesional edema is associated with a higher probability of a positive EITB result in patients with CMNCC, suggesting a synchronicity in the mechanisms associated with formation of perilesional edema and the antibody response in this subtype. In patients with enhancing granulomas, edema is not an independent predictor of a positive EITB, suggesting that the enhancement itself is associated with a strong antibody response.

Secondary Bacterial Infection of a Solitary Cysticercus Granuloma

The most common presenting form of neurocysticercosis in the Indian subcontinent is a solitary cysticercus granuloma (SCG). Patients with typical SCGs almost never require any form of surgical intervention. Herein, we report an extremely rare case of bacterial superinfection of a left frontal SCG in a 23-year-old female, resulting in severe perilesional edema and mass effect. The patient had to undergo an emergency left decompressive hemicraniectomy and excision of the infected granuloma. Serum enzyme-linked immunoelectrotransfer blot (EITB) for cysticercal antibodies was positive and histopathological examination of the lesion revealed a cysticercus. The culture of the pus from within the lesion grew vancomycin-resistant Enterococcus spp. for which she was treated with linezolid for 6 weeks. At 6 months follow-up, she had residual motor dysphasia, right homonymous hemianopia, and right hemiparesis but was steadily improving. Secondary bacterial infection of an SCG is very uncommon and can be devastating. A high index of suspicion is therefore required when there is disproportionate perilesional edema and mass effect.

Taenia solium Cysticercosis and Its Impact in Neurological Disease

Taenia solium neurocysticercosis (NCC) is endemic in most of the world and contributes significantly to the burden of epilepsy and other neurological morbidity. Also present in developed countries because of immigration and travel, NCC is one of few diseases targeted for eradication. This paper reviews all aspects of its life cycle (taeniasis, porcine cysticercosis, human cysticercosis), with a focus on recent advances in its diagnosis, management, and control. Diagnosis of taeniasis is limited by poor availability of immunological or molecular assays. Diagnosis of NCC rests on neuroimaging findings, supported by serological assays. The treatment of NCC should be approached in the context of the particular type of infection (intra- or extraparenchymal; number, location, and stage of lesions) and has evolved toward combined symptomatic and antiparasitic management, with particular attention to modulating inflammation. Research on NCC and particularly the use of recently available genome data and animal models of infection should help to elucidate mechanisms of brain inflammation, damage, and epileptogenesis.

Antiparasitic treatment of neurocysticercosis - The effect of cyst destruction in seizure evolution

Antiparasitic agents against Taenia solium cysticercosis have been in use since 1979, although its use has been questioned on the basis that cysts would die naturally and thus treatment-induced inflammation is unnecessary. In addition, isolated reports have also questioned whether neurocysticercosis (NCC) is a cause of epilepsy. After more than three and a half decades, a large body of evidence is available. Little if any doubt exists about NCC as a cause of seizures - NCC is consistently associated with seizures when appropriate groups are compared, and in a large subset of cases, seizure semiology correlates with the anatomical location of lesions. Cyst degeneration and the subsequent inflammatory reaction increase seizure expression, although patients with non-inflamed cysts may have seizures, as do patients with long-standing, not inflamed calcified scars. Assessment of the evidence on cysticidal efficacy, safety, and the impact of cyst destruction in decreasing seizures leads to the conclusion that the benefits of antiparasitic treatment in parenchymal brain cysticercosis clearly outweigh the risks, and have provided substantive evidence of the role of NCC as a cause of seizures and epilepsy. Antiparasitic therapy should be considered a primary option in the management of patients with live or degenerating brain NCC cysts. This article is part of a Special Issue entitled "Neurocysticercosis and Epilepsy".

Neurocysticercosis: Diagnostic problems & current therapeutic strategies

Neurocysticercosis (NCC) is the most common single cause of seizures/epilepsy in India and several other endemic countries throughout the world. It is also the most common parasitic disease of the brain caused by the cestode Taenia solium or pork tapeworm. The diagnosis of NCC and the tapeworm carrier (taeniasis) can be relatively inaccessible and expensive for most of the patients. In spite of the introduction of several new immunological tests, neuroimaging remains the main diagnostic test for NCC. The treatment of NCC is also mired in controversy although, there is emerging evidence that albendazole (a cysticidal drug) may be beneficial for patients by reducing the number of seizures and hastening the resolution of live cysts. Currently, there are several diagnostic and management issues which remain unresolved. This review will highlight some of these issues.

Pathogenesis of Taenia solium taeniasis and cysticercosis

Taenia solium infections (taeniasis/cysticercosis) are a major scourge to most developing countries. Neurocysticercosis, the infection of the human nervous system by the cystic larvae of this parasite, has a protean array of clinical manifestations varying from entirely asymptomatic infections to aggressive, lethal courses. The diversity of clinical manifestations reflects a series of contributing factors which include the number, size and location of the invading parasites, and particularly the inflammatory response of the host. This manuscript reviews the different presentations of T. solium infections in the human host with a focus on the mechanisms or processes responsible for their clinical expression.

Enhanced steroid dosing reduces seizures during antiparasitic treatment for cysticercosis and early after

OBJECTIVE

Neurocysticercosis (NCC) is a major cause of seizures and epilepsy in endemic countries. Antiparasitic treatment of brain cysts leads to seizures due to the host's inflammatory reaction, requiring concomitant steroids. We hypothesized that increased steroid dosing will reduce treatment-associated seizures.

METHODS

Open-label randomized trial comparing 6 mg/day dexamethasone for 10 days (conventional) with 8 mg/day for 28 days followed by a 2-week taper (enhanced) in patients with NCC receiving albendazole. Follow-up included active seizure surveillance and brain imaging. Study outcomes were seizure days and patients with seizures, both measured in days 11-42. Additional analyses compared days 1-10, 11-21, 22-32, 33-42, 43-60, and 61-180.

RESULTS

Thirty-two individuals were randomized into each study arm; two did not complete follow-up. From days 11 to 42, 59 partial and 6 generalized seizure days occurred in 20 individuals, nonsignificantly fewer in the enhanced arm (12 vs. 49, p = 0.114). The numbers of patients with seizures in this period showed similar nonsignificant differences. In the enhanced steroid arm there were significantly fewer days and individuals with seizures during antiparasitic treatment (days 1-10: 4 vs. 17, p = 0.004, and 1 vs. 10, p = 0.003, number needed to treat [NNT] 4.6, relative risk [RR] 0.1013, 95% confidence interval [CI] 0.01-0.74) and early after dexamethasone cessation (days 11-21: 6 vs. 27, p = 0.014, and 4 vs. 12, p = 0.021, NNT 4.0, RR 0.33, 95% CI 0.12-0.92) but not after day 21. There were no significant differences in antiparasitic efficacy or relevant adverse events.

SIGNIFICANCE

Increased dexamethasone dosing results in fewer seizures for the first 21 days during and early after antiparasitic treatment for viable parenchymal NCC but not during the first 11-42 days, which was the primary predetermined time of analysis.

Quantitative serial T2 relaxometry: a prospective evaluation in solitary cerebral cysticercosis

We describe the evolution of quantitative T2 relaxometry values on serial MRI in patients with a solitary cerebral cysticercal lesion (SCCL), and determine whether albendazole therapy affects T2 relaxation (T2R) values. Patients with new-onset seizures and MRI-confirmed SCCL were randomized to treatment with albendazole and antiepileptics ("treatment group") or antiepileptics only ("controls"). Serial MRI including T2 relaxometry was performed at baseline, three, six, 12, and 24 months. Of 123 patients recruited, 81 had more than three MRI scans (treatment group: 37; controls: 44; 58 patients had five scans). The lesion wall at baseline showed a mean T2R value of 152.3 ms, centre 474.9 and perilesional parenchyma 338.5 ms. These were significantly higher than those from normal parenchyma (114 ms). Over time, most sharply in the initial three months, T2R values fell but even at 24 months, they remained above those from normal parenchyma. A slight increase in T2R values from the lesion centre at six months was thought to represent the initiation of gliosis. In the treatment group, T2R values approached normal at 24 months, while controls had persistently higher T2R values. The decline in T2R values at six months was more prominent in the treatment group. T2R values at baseline and at three months differed significantly depending on the stage of the lesion, being higher in stage 2 SCCL. T2R values from SCCL declined over 24 months, being significantly higher in earlier stages of degeneration. A mild increase after six months may be due to the initiation of gliosis. T2R values appear to decline faster in patients who receive albendazole.

Immunological and molecular diagnosis of cysticercosis

Cysticercosis, the infection with the larval stage of Taenia solium, is a cause of neurological symptoms including seizures, affecting the quality of life of patients and their families. Diagnosis focuses on brain imaging and serological tests are mostly used as confirmatory tools. Most cases, however, occur in poor endemic areas, where both kinds of diagnostic tools are poorly available. Development of point of care diagnostic tests is one of the most important priorities for cysticercosis researches today. The ideal point of care test would require detection of viable cysticercosis and hopefully identify cases with severe or progressive forms of neurocysticercosis, leading to referral of the patient for specialized medical attention. This manuscript describes the evolution of the serological diagnosis of cysticercosis over time, and the characteristics of the most common currently available tools, their advantages and disadvantages, and their potential use in future diagnostic tests.

Drug therapy for solitary cysticercus granuloma: a systematic review and meta-analysis

OBJECTIVE

The effectiveness of anthelminthic and corticosteroid drug therapy in parenchymal neurocysticercosis is well established. The treatment of parenchymal solitary cysticercus granuloma (SCG), however, remains controversial. We attempted to obtain a consistent estimate of the efficacy of anthelminthic and corticosteroid drug treatment in SCG.

METHODS

Randomized-controlled trials (RCTs) comparing rates of seizure freedom, granuloma resolution, and residual calcification in individuals with SCG treated with anthelminthic or corticosteroid drugs with those treated with antiepileptic drugs (AEDs) alone were systematically reviewed and quantified using fixed- or random-effects meta-analysis.

RESULTS

Fifteen RCTs were identified for inclusion. Ten RCTs assigned 765 people with SCG to AED treatment with or without anthelminthic drug (albendazole) treatment. A further 5 RCTs assigned 457 people with SCG to AED treatment with or without corticosteroid drugs. Anthelminthic treatment was associated with significantly increased rates of seizure freedom (nonevent odds ratio: 2.45; 95% confidence interval: 1.49-4.03; p = 0.0004) and significantly higher rates of granuloma resolution (odds ratio: 2.09; 95% confidence interval: 1.41-3.00; p = 0.0003), but did not alter the risk of residual calcification. Corticosteroid treatment was not significantly associated with any outcome.

CONCLUSIONS

Anthelminthic treatment with albendazole provides improved rates of seizure freedom and hastens resolution of the granuloma. The role of corticosteroid treatment remains uncertain. The benefits (or lack thereof in the case of corticosteroids) are consistent when measured across different time points after treatment.

Neurocysticercosis

Cysticercosis, an infection caused by the cystic larvae of the pork tapeworm Taenia solium, is one of the most frequent parasitic infections of the human nervous system (neurocysticercosis). It is endemic in most of Latin America, the sub-Saharan Africa, and vast parts of Asia, including the Indian subcontinent. It has also been increasingly diagnosed in developed countries because of migration of people from endemic zones and exposure in travelers. The life cycle involves the development of the adult tapeworm in the human small intestine (after ingesting infected pork with cysts) and larval infection in pig tissues (after ingesting human stools containing the eggs of the tapeworm). Humans get infected by the fecal-oral route, most often from a direct contact with an asymptomatic Taenia carrier. Most common clinical presentations are seizures (particularly late-onset seizures), chronic headaches, and intracranial hypertension. However, cysticerci can locate anywhere in the human nervous system, thus potentially causing almost any neurological syndrome and making clinical diagnosis a difficult task. Neuroimaging is the main diagnostic tool, and specific serology confirms the diagnosis and helps to define the diagnosis when images are unclear. Factors such as location (extraparenchymal versus intraparenchymal), number, size and evolutive stage of the parasites determine the clinical manifestations, therapeutic approach, and prognosis. Management includes symptomatic drugs (analgesics, antiepileptic drugs, anti-inflammatory agents) and in many cases cysticidal drugs, either albendazole or praziquantel. In recent years, efforts have focused on transmission control and potential elimination in endemic regions.

Cysticercosis of the central nervous system: how should it be managed?

PURPOSE OF REVIEW

Taenia solium neurocysticercosis (NCC) has been long recognized as an important cause of neurological morbidity in most of the world. Unwarranted generalization of diagnostic and treatment recommendations made it difficult to assess individual prognosis and responses for each type of NCC. Understanding of the main clinical presentations (dependent on number, location, size, and stage of parasites, as well as on the immune response of the host) allows a better view of treatment options and expected outcomes.

RECENT FINDINGS

Current treatment options are still limited and involve symptomatic agents, antiparasitic agents, or surgery. The importance of adequate symptomatic management, the potential for improved antiparasitic treatment regimes, in particular combination therapy, and the increasingly important role of minimally invasive neurosurgery are also reviewed in this article.

SUMMARY

Treatment decisions in NCC should be individualized in relation to the type of NCC. Initial measures should focus on the symptomatic management before considering antiparasitic therapy when appropriate. Appropriate patient categorization, new antiparasitic regimes, and minimally invasive surgery are improving the prognosis of patients with NCC.

Short-course of prednisolone in solitary cysticercus granuloma: a randomized, double-blind, placebo-controlled trial

PURPOSE

To determine the effect of administration of a short course of prednisolone on seizure and radiologic outcome in patients with solitary cysticercus granuloma (SCG).

METHODS

One hundred forty-eight subjects presenting with new-onset seizures (<15 days duration) and with SCG demonstrated on imaging studies were randomly allocated to either treatment with prednisolone (40-60 mg/day for 2 weeks) or placebo in addition to standard antiepileptic drug therapy. The subjects were followed up for seizure recurrence for 9 months. Repeat computed tomography (CT, at 3 months) and magnetic resonance imaging (MRI, at 6 months) to evaluate resolution and calcification of the lesion.

KEY FINDINGS

There was no difference in the proportion of subjects with seizure recurrence during the follow-up period in the treatment (n = 16, 21.9%) and control (n = 19, 25.33%) groups (p = 0.7). However, generalized seizures occurred in a significantly lesser proportion of subjects in the treatment group (n = 3, 15.79%) in comparison to the control group (n = 12, 60.00%) (p = 0.015). There were no significant differences in the proportion of subjects with complete resolution of the SCG on repeat CT at 3 months [treatment group (27, 46.7%) and control group (23, 39.8%); p = 0.453] and repeat MRI at 6 months [treatment group (28, 46.7%) and control group (21, 38.9%); p = 0.402].

SIGNIFICANCE

The administration of a short course of prednisolone does not offer significant improvement in seizure control, although a benefit in terms of reducing the likelihood of generalized seizures is possible. Furthermore, it does not improve the chances of resolution of the SCG on follow-up imaging studies.

A diagnostic and therapeutic scheme for a solitary cysticercus granuloma

BACKGROUND

Solitary cysticercus granuloma (SCG) is one of the most common forms of presentation of neurocysticercosis (NCC). The diagnostic workup and management approach to this condition remain uncertain and controversial.

OBJECTIVE

To review evidence and develop a consensus approach to the diagnosis and treatment of SCG.

METHODS

A multidisciplinary expert group meeting was convened in order to review and discuss various aspects of management of patients with SCG. Evidence reviewed was classified and a consensus was evolved according to standard protocols.

RESULTS

SCG is commonly recognized on CT as an enhancing lesion measuring <20 mm. Further evaluation with MRI does not add much information. The use of antihelminthic agents (specifically, albendazole in combination with corticosteroids) and corticosteroids alone have been shown to improve radiologic resolution and seizure outcome in patients with SCG. However, the sizes of the effects are modest. By convention, all patients with SCG presenting with seizures are initiated on antiepileptic drugs (AEDs). Available evidence suggests that withdrawal of AEDs after complete resolution of the SCG is safe. There is a high risk of seizure relapse after AED withdrawal in patients with calcific residue following resolution of the SCG. The duration of AED prophylaxis in these individuals is unclear.

CONCLUSIONS

It is desirable to have large, multicenter trials with sufficiently long follow-up, comparing outcomes with the use of antihelminthics with or without corticosteroids and corticosteroids alone in order to dissect out the benefits accrued due to each of these classes of drugs.

Neurocysticercosis: unraveling the nature of the single cysticercal granuloma

A single enhancing lesion in the brain parenchyma, also called an inflammatory granuloma, is a frequent neurologic diagnosis. One of the commonest causes of this lesion is human neurocysticercosis, the infection by the larvae of the pork tapeworm, Taenia solium. Following the demonstration that viable cysticercosis cysts survive in good conditions for several years in the human brain, single cysticercal granulomas have been consistently interpreted as representing late degeneration of a long-established parasite. On the basis of epidemiologic, clinical, and laboratory evidence detailed in this article, we hypothesize that in most cases these inflammatory lesions correspond to parasites that die in the early steps of infection, likely as the natural result of the host immunity overcoming mild infections.

Natural history of solitary cerebral cysticercosis cases after albendazole therapy: a longitudinal follow-up study from India

OBJECTIVES

To find out natural course of solitary cerebral cysticercosis (SCC) cases after treating them with 2 weeks albendazole therapy.

MATERIAL AND METHODS

All patients with SCC were treated with 2 weeks of albendazole therapy with follow-up radiological scan at 6 months and 2 years. The evolution of lesion was noted as complete resolution, calcification or persistent active. Antiepileptic drugs (AED) prophylaxis was given for 1 year in patients with complete resolution and for 2 years in calcified lesion, respectively. AED was continued in persistent lesion group till it became calcified or resoluted completely. One-year follow-up was done in all after stopping AED.

RESULTS

Among 345 cases, 226 (65.5%) had complete resolution with very low seizure relapse rate with 1 year of seizure free period on AED treatment. On the contrary, 105 (30.5%) had calcified lesion with high seizure relapse rate after stopping AED treatment with 2 years of seizure free period. Fourteen patients (4%) could not stop their antiepileptic medication at all because of active lesion.

CONCLUSION

Two-third of patients with SCC have favorable outcome with complete resolution and needs short-term AED prophylaxis and the rest one-third requires long AED treatment to prevent seizures.

Epilepsy and neurocysticercosis: an incidence study in a Peruvian rural population

BACKGROUND

Epilepsy is a serious neurological disorder and neurocysticercosis (NCC), the central nervous system infection by the larvae of Taenia solium, is the main cause of acquired epilepsy in developing countries. NCC is becoming more frequent in industrialized countries due to immigration from endemic areas. Previously reported epilepsy incidences range from 30 to 50/100,000 people in industrialized countries and 90 to 122/100,000 people in developing countries.

OBJECTIVES

To determine the incidence of epilepsy in a cysticercosis endemic area of Peru.

METHODS

A screening survey for possible seizure cases was repeated biannually in this cohort for a period of 5 years (1999-2004) using a previously validated questionnaire. All positive respondents throughout the study were examined by a trained neurologist in the field to confirm the seizure. If confirmed, they were offered treatment, serological testing, neuroimaging (CT scans and MRI) and clinical follow-up.

RESULTS

The cohort study comprised 817 individuals. The overall epilepsy incidence rate was 162.3/100,000 person-years, and for epileptic seizures, 216.6/100,000 person-years. Out of the 8 individuals who had epileptic seizures, 4 had markers for NCC (neuroimaging and/or serology).

CONCLUSION

The incidence of epilepsy in this area endemic for cysticercosis is one of the highest reported worldwide.

Susceptibility weighted imaging in the diagnostic evaluation of patients with intractable epilepsy

AIM

Dedicated magnetic resonance imaging (MRI) protocol can diagnose epileptogenic abnormalities in patients with intractable epilepsy. However, it is not sufficiently sensitive to detect small calcified lesions that may result from infections, tumors, or vascular malformations. This study aims to study the impact of the addition of T2*gradient echo/susceptibility weighted imaging (T2*GRE/SWI) sequence to a dedicated MRI protocol.

METHOD

One hundred thirty-seven patients with intractable epilepsy underwent MRI using conventional epilepsy protocol with addition of T2*GRE/SWI sequence. Comparison of the images with and without these sequences was done for detection of calcified abnormalities/vascular abnormalities. In patients with calcified lesions, MRI findings were correlated either with histopathology or computerized tomography (CT) to confirm the presence of calcification.

RESULTS

In 16 patients the sequence gave additional information compared to conventional imaging protocol. The sequence helped in better characterization of lesions in all patients. In three patients it helped in detecting the lesion and in another three it appeared useful as it best characterized the lesions. Additional lesions were detected in two patients with old calcified granulomas. Important additional information was supplied in four patients, whereas in the remaining patients lesion conspicuity was increased.

CONCLUSION

T2*GRE/SWI sequence should form part of routine epilepsy protocol as it increases sensitivity by detecting occult calcified lesions or vascular malformations that may be responsible for the patient's seizures. This is especially important in patients from developing countries who have post-infective calcified lesions responsible for seizures and who undergo only MRI as the imaging modality for intractable seizures.

Perilesional brain oedema and seizure activity in patients with calcified neurocysticercosis: a prospective cohort and nested case-control study

BACKGROUND

Cysticercosis due to Taenia solium is a cause of adult-acquired seizures and epilepsy even in patients with only calcified larval cysts. Transient perilesional brain oedema is seen around the calcified foci but its importance, association with seizures, incidence, and pathophysiology are unknown.

METHODS

110 patients with only calcified lesions and a history of seizures or severe headaches were followed prospectively in a cohort design to assess the incidence of seizure relapse. In a nested case-control substudy, perilesional oedema was assessed by MRI at the time of seizure in symptomatic patients and in matched asymptomatic controls taken from the study population.

FINDINGS

Between November, 1999, and December, 2006, 29 patients had an incident seizure during a median follow up of 32.33 (SD 19.99) months, with an estimated 5-year seizure incidence of 36% (95% CI 25% to 49%). 24 of 29 (83%) patients with seizure relapse had an MRI evaluation within 5 days of the event; perilesional oedema was seen in 12 patients (50%) compared with two (9%) of 23 asymptomatic matched controls.

INTERPRETATION

Perilesional oedema is common and associated with episodic seizure activity in patients with calcified neurocysticercosis. Our findings are probably representative of symptomatic patients in regions where T solium neurocysticercosis is endemic and suggest a unique and possibly preventable cause of seizures in this population.

T2 relaxometry of ring lesions of the brain

AIM

To differentiate two common aetiologies of "ring lesions," tuberculomas and cysticercal cysts, using T2 relaxometry.

MATERIALS AND METHODS

Fifty-five ring-enhancing lesions of the brain (32 cysticercal cysts; 23 tuberculomas) in 27 patients with focal seizures were studied for T2 relaxation times.

RESULTS

The mean T2 relaxation times of cysticercal cysts was 617 ms (range 305-1365 ms; SD 272.2) and that of tuberculomas 161 ms (range 83-290 ms; SD 60.3; 95% confidence).

CONCLUSION

T2 relaxometry is a simple, reliable and valuable non-invasive magnetic resonance imaging (MRI) technique to differentiate between intracranial cysticercal cysts and tuberculomas, and may be incorporated in routine diagnostic protocols.

Cysticercosis Headache: An Important Differential of Childhood Headache Disorder in Endemic Countries

Neurocysticercosis is a common pediatric central nervous system (CNS) disease in endemic areas, presenting usually with seizures but has pleomorphic manifestations, including migraine-like secondary headache. We herein report a pediatric patient with tension-type headache as the sole presenting feature of single cysticercus granuloma.

Treatment of neurocysticercosis: current status and future research needs

Here we put forward a roadmap that summarizes important questions that need to be answered to determine more effective and safer treatments. A key concept in management of neurocysticercosis is the understanding that infection and disease due to neurocysticercosis are variable and thus different clinical approaches and treatments are required. Despite recent advances, treatments remain either suboptimal or based on poorly controlled or anecdotal experience. A better understanding of basic pathophysiologic mechanisms including parasite survival and evolution, nature of the inflammatory response, and the genesis of seizures, epilepsy, and mechanisms of anthelmintic action should lead to improved therapies.

Intravenous methyl prednisolone in patients with solitary cysticercus granuloma: A random evaluation

PURPOSE

To evaluate the role of intravenous methyl prednisolone in patients with solitary cysticercus granuloma with new-onset seizures.

METHODS

In this open-label, randomized, prospective, follow-up study, 52 patients with new-onset seizures and a single enhancing CT lesion of cysticercus were randomly divided in two groups to receive either intravenous methyl prednisolone for 5 days along with antiepileptic drug (n=25) or antiepileptic drug monotherapy (n=27) alone. The patients were followed up for at least for 9 months. Repeat CT scans were performed after 2 months.

RESULTS

After 2 months, lesion disappeared in 60% patients of intravenous methyl prednisolone group and 18.5% patients receiving only antiepileptic drug (p=0.001). As far as seizure recurrence was concerned, a lower number (16% versus 33%) of intravenous methyl prednisolone treated patient had recurrence, the difference was insignificant.

CONCLUSION

Intravenous methyl prednisolone therapy helps in early resolution of solitary cysticercus granuloma.

Epidemiologic classification of seizures associated with neurocysticercosis: observations from a sample of seizure disorders in neurologic care in India

AIMS

To determine the etiologic role of neurocysticercosis (NC) in a hospital-based sample of epilepsies divided according to International League Against Epilepsy (ILAE) epidemiological criteria and number of seizures prior to presentation.

METHODS

A sample comprising 1026 consecutive patients with either definite seizures or epilepsy attending a Neurology Outpatient Service was divided into four subgroups: single seizure (n = 314), incident epilepsy (n = 127), prevalent epilepsy (n = 398) and recurrent acute symptomatic seizures (RASS) (n = 175). The etiologic contribution of NC to each of the subgroups was examined with imaging studies.

RESULTS

Neurocysticercosis was diagnosed on imaging studies in 34.6% of patients with seizure disorder of any type, 59.2% of those with a single seizure, 23.7% of those with recurrent seizure disorder, 92.0% of those with RASS, none of cases of incident epilepsy and 2.0% with prevalent epilepsy. A diagnosis of NC was significantly associated with single seizures (P < 0.001).

CONCLUSIONS

Imaging abnormalities consistent with NC are frequently noted in persons presenting with a single seizure in neurologic care in NC-endemic countries like India. The probability of diagnosing NC diminishes with increasing numbers of seizures. Among samples of individuals with recurrent-unprovoked seizures, it is rare for imaging to demonstrate lesions of NC.

Differential Diagnosis Between Cerebral Tuberculosis and Neurocysticercosis by Magnetic Resonance Spectroscopy

Single enhancing brain lesions (SELs), mostly as a result of neurocysticercosis or tuberculosis, are a common cause of seizures. Ten patients with SELs caused by neurocysticercosis (n=6) or tuberculosis (n=4) were examined by proton magnetic resonance spectroscopy. Tuberculomas had a high peak of lipids, more choline, and less N-acetylaspartate and creatine. The choline/creatine ratio was greater than 1 in all tuberculomas but in none of the cysticerci. Magnetic resonance spectroscopy differentiates SELs caused by cysticercosis or tuberculosis and may avoid brain biopsies or unnecessary antituberculosis treatments.

Prednisolone-responsive headache in patients with solitary cysticercus granuloma and seizures

BACKGROUND

Solitary cysticercus granuloma is the commonest imaging abnormality in Indian patients with new-onset seizures. Few patients, in addition, complain of disabling headache.

OBJECTIVE

To report our experience of 16 patients with new-onset headache, seizures, and solitary cysticercus granuloma.

METHODS

Sixteen consecutive patients, who had moderate to severe new-onset headache and fulfilled the diagnostic criteria of solitary cysticercus granuloma, were included in the study. The inclusion criteria were: occurrence of seizures, minimal or no neurologic deficit, absence of papilledema, no evidence of any systemic disorder, and computed tomography showing a single ring/disk-enhancing lesion of <20 mm in diameter. Patients received antiepileptic monotherapy, oral analgesics, and prednisolone (1.5 mg/kg/day for 7 days). Prednisolone was then tapered over the next 7 days. Patients were followed for 6 months. Follow-up computed tomography was performed after 2 months; in all 16 patients, the scans showed complete disappearance of the lesion.

RESULTS

After 14 days (at first follow-up), all patients reported significant improvement in headache. Follow-up after 2 months revealed that all patients were headache-free. None of the patients reported any recurrence of headache.

CONCLUSION

This open-label study suggests the effectiveness of prednisolone for disabling headache in Indian patients with solitary cysticercus granuloma and seizures. There is a need, however, for more scientifically rigorous studies for further confirmation of our results.

Calcific neurocysticercosis and epileptogenesis

Neurocysticercosis is responsible for increased rates of seizures and epilepsy in endemic regions. The most common form of the disease, chronic calcific neurocysticercosis, is the end result of the host's inflammatory response to the larval cysticercus of Taenia solium. There is increasing evidence indicating that calcific cysticercosis is not clinically inactive but a cause of seizures or focal symptoms in this population. Perilesional edema is at times also present around implicated calcified foci. A better understanding of the natural history, frequency, epidemiology, and pathophysiology of calcific cysticercosis and associated disease manifestations is needed to define its importance, treatment, and prevention.

Corticosteroids versus albendazole for treatment of single small enhancing computed tomographic lesions in children with neurocysticercosis

Single small enhancing computed tomographic (CT) lesions representing cysticercus granuloma are a common cause of focal seizures in children. Controversy exists regarding the efficacy of various modalities of treatment. We conducted a randomized prospective trial to evaluate the efficacy of corticosteroids, albendazole, and corticosteroids with albendazole in children with focal seizures and single small enhancing CT lesions. The study population consisted of 133 children with focal seizures of recent onset (< 3 months) and single small enhancing CT lesions who presented to the Neurocysticercosis Clinic of Pediatric Neurology Services at the Advanced Pediatrics Centre, Postgraduate Institute of Medical Education and Research, an urban teaching and tertiary care hospital in Chandigarh, North India. All children were randomly assigned to receive corticosteroids (group S), albendazole (group A), or both corticosteroids and albendazole (group SA) for 28 days. CT was done at 3 and 6 months after enrollment in the study. Of the 133 patients enrolled, 23 were lost to follow-up. Of the remaining 110 patients, 38 patients were in group S, 37 in group A, and 35 in group SA. All children were followed up for at least 18 months. Disappearance of the lesion on CT scan was noted in 52.6% of patients in group S, 59.5% in group A, and 62.9% in Group SA (P > .1) at the 3-month follow-up. After the 6-month follow-up, disappearance of the lesion was noted in 76.3% in group S, 75.7% in group A, and 74.2% in group SA (P > .1). Twenty-three patients had seizure recurrence while on antiepilepsy drugs: 36.8% of patients in group S, 13.5% in group A, and 11.4% in group SA (P < .05). Seizure recurrence after antiepilepsy drug withdrawal was seen in seven children (three in group S and two each in groups A and SA). In conclusion, there was no significant difference in resolution of CT lesions in the three therapy groups at 3 and 6 months of follow-up. Children in the corticosteroid group had significantly more seizure recurrences while on antiepilepsy drugs.

Clinical profile of Solitary Seizures

BACKGROUND

Solitary seizure is one of the controversies in neurology. This study was taken up to study the clinical profile of solitary seizure and the factors related to seizure recurrence with a view to evolve guidelines for management.

METHODS

We studied 150 cases of solitary seizure. All our patients were males. The age varied from 18-52 years. The diagnosis of seizure was confirmed with history. Apart from clinical neurological examination, blood counts, urinalysis and screening investigations to exclude possible underlying metabolic disorders were done. Inter-ictal EEG and contrast enhanced CT scan were done.

RESULTS

CT scan was abnormal in 28 cases. EEG was abnormal in 33; clinical abnormality was noted in 15 cases. Median follow up duration was 1.2 years. 18 patients had seizure recurrence. Type of seizure, EEG findings (normal or abnormal) and treatment with antiepileptic drugs did not have any effect on seizure recurrence. Seizure recurrence was less common in presence of CT scan abnormality though it was not significant statistically. Routine laboratory tests of blood count, blood sugar and urinalysis were normal in all cases.

CONCLUSION

In cases of solitary seizure, type of seizure, results of EEG and CT scan findings are not likely to predict seizure recurrence. Treatment with antiepileptic drugs does not prevent seizure recurrence. Laboratory investigations like blood counts, urinalysis and blood sugar estimation are unlikely to be of value in routine work-up of these cases.

Interictal serum S100B levels in chronic neurocysticercosis and idiopathic epilepsy

OBJECTIVE

To assess whether serum S100B levels could reflect a glial response in patients with epilepsy secondary to neurocysticercosis (NCC) and with idiopathic epilepsy.

SUBJECTS AND METHODS

Serum S100B levels were measured using an immunoluminometric assay in 20 patients with focal epilepsy related to chronic NCC (NCC group), and 19 patients with focal epilepsy (EPI group), matched by epidemiological and clinical data. Epileptic patients were compared with 20 healthy controls (CON group) matched by age and sex.

RESULTS

No difference was observed in S100B levels among NCC, EPI and CON groups (P>0.39). Serum S100B levels were not affected by antiepileptic drugs, frequency and type of seizures. Preliminarily, significantly higher levels of S100B were observed in patients with bilateral electroencephalographic (EEG) findings than in patients with unilateral and normal EEG findings (P<0.05).

CONCLUSION

Serum S100B is normal in patients with focal epilepsy related or not to chronic NCC.

Pyruvate: An in vivo marker of cestodal infestation of the human brain on proton MR spectroscopy

PURPOSE

To study intracranial cestodal cysts using in vivo proton magnetic resonance spectroscopy ((1)H MRS) in an effort to identify metabolite(s) that may help in recognizing the parasitic etiology and, perhaps, viability of such tapeworm cysts. Cestodal infestations of the human central nervous system (CNS)-cysticercosis and hydatidosis-are not rare. Identification of a scolex is considered diagnostic of cysticercosis on imaging. In its absence, however, the features are non-specific.

MATERIALS AND METHODS

Three patients with intracranial hydatid cysts and 13 patients with intracranial cysticercal cysts (four intraventricular, seven parenchymal, and two subarachnoid racemose cysts) were studied on a 1.5-T MR system. In vivo (1)H MRS was performed by multivoxel two-dimensional hybrid chemical shift imaging technique (TE = 135 msec). In vitro (1)H NMR and mass spectroscopy (matrix assisted laser desorption/ionization [MALDI]) were performed on excised cysticercal and hydatid cyst fluid. MALDI spectra for pyruvate and succinate were also obtained.

RESULTS

Alanine, pyruvate, and acetate were seen in all the three hydatid cysts. Lactate was seen in racemose cysticercal cysts. A large resonance at 2.4 ppm, confirmed as pyruvate at mass spectroscopy, was seen in 13 cestodal cysts. Pyruvate was not seen in one each of racemose, intraventricular, and parenchymal cysticercal cysts.

CONCLUSION

Pyruvate is the predominant metabolite in cestodal cysts infesting the human CNS. It may be a marker of parasitic etiology and perhaps that of viability of such intracranial cysts.

Neurocysticercosis in children: clinical findings and response to albendazole therapy in a randomized, double-blind, placebo-controlled trial in newly diagnosed cases

The clinical findings of neurocysticercosis, diagnosed primarily on the basis of computed tomography (CT), and response to albendazole therapy in a randomized, double-blind, placebo-controlled trial were studied in 72 newly diagnosed children aged 1.5-12 years admitted to hospital in New Delhi, India, during March to July 2000. The lesions by initial CT were mostly single with perilesional oedema, and were located in the parietal lobes. The most common clinical finding was partial seizure (79.2%). The outcome of the albendazole trial was assessed through changes in CT lesions and status of seizure after 6 months of follow-up; about 55% of the lesions had disappeared and about 80% of the children were seizure-free. The frequency of healing of CT lesions in the albendazole-treated group and placebo group was 54.2% and 55.2%, respectively, and the frequency of a seizure-free state in the albendazole-treated group and placebo group was 87.5% and 77.5%, respectively; the differences were not statistically significant. Changes in lesions by CT and the recurrence of seizures after 6 months of follow-up were not related to the number of lesions by initial CT and albendazole was not beneficial in neurocysticercosis in children with ring-enhancing lesions in CT.

Imaging findings in neurocysticercosis

The diagnosis of neurocysticercosis was greatly improved by the introduction of computed tomography (CT) and magnetic resonance imaging (MRI). These techniques demonstrate the number and topography of lesions, their stage of involution, and the degree of inflammatory reaction of the host against the parasites and have largely replaced previous radiological procedures such as plain roentgenograms, pneumoencephalograms, cerebral angiography and myelography. In general, MRI provides better image detection and definition. The possibility of multiplanar reconstruction of images, its capability to visualize the posterior fossa without bone artifacts, and its high contrast resolution (far superior to that of CT) allow MRI to recognize many forms of cysticercosis not visualized on CT. However, the costs of MRI are high and the equipment is scarcely available in many endemic countries, and its sensitivity for the detection of calcified lesions is poor. CT remains the best screening neuroimaging procedure for patients with suspected neurocysticercosis, and MRI is the imaging modality of choice for the evaluation of patients with intraventricular cysticercosis, brainstem cysts and small cysts located over the convexity of cerebral hemispheres. Its better image definition also suggests that MRI is superior to CT in the follow-up of the patients after therapy.

Neurocysticercosis in children: clinical characteristics and outcome

A study was undertaken on 176 children with neurocysticercosis to determine the clinical behaviour and long-term outcome of cases. The children were followed up prospectively in the paediatric neurology clinic for 6 years. Diagnosis was based primarily on CT scans. All the CT lesions were parenchymal and mostly single (87%) with ring enhancement and peri-lesional oedema. Partial seizure was the predominant presenting seizure type. About 65% of cases had recurrences at varying intervals during treatment. Albendazole therapy given to some cases did not appear to have any beneficial effect on seizure control. Repeat CTs done at varying intervals after the first seizures showed disappearance of the lesions in about 50% of cases. The majority of lesions disappeared without the use of albendazole. Recurrence of seizures after withdrawal of anti-epileptic medication was observed in 19% of the cases. Parenchymal neurocysticercosis in children commonly presents with partial seizures and ring lesions on CT. The disease can be managed well by anti-epileptic medication alone and the prognosis is good.

Current consensus guidelines for treatment of neurocysticercosis

Taenia solium neurocysticercosis is a common cause of epileptic seizures and other neurological morbidity in most developing countries. It is also an increasingly common diagnosis in industrialized countries because of immigration from areas where it is endemic. Its clinical manifestations are highly variable and depend on the number, stage, and size of the lesions and the host's immune response. In part due to this variability, major discrepancies exist in the treatment of neurocysticercosis. A panel of experts in taeniasis/cysticercosis discussed the evidence on treatment of neurocysticercosis for each clinical presentation, and we present the panel's consensus and areas of disagreement. Overall, four general recommendations were made: (i) individualize therapeutic decisions, including whether to use antiparasitic drugs, based on the number, location, and viability of the parasites within the nervous system; (ii) actively manage growing cysticerci either with antiparasitic drugs or surgical excision; (iii) prioritize the management of intracranial hypertension secondary to neurocysticercosis before considering any other form of therapy; and (iv) manage seizures as done for seizures due to other causes of secondary seizures (remote symptomatic seizures) because they are due to an organic focus that has been present for a long time.

Single enhancing computerized tomography-detected lesion in immunocompetent patients

Single enhancing computerized tomography (CT)-documented lesions may occur in several infectious and neoplastic diseases of the central nervous system and are the most common radiological abnormality seen in patients with acute-onset seizures in India and many other developing countries. Similar CT-documented lesions have also been reported in the developed world where these lesions are often considered to be caused by neoplasms or tuberculoma. Histopathological studies in India and even in some developed countries revealed that neurocysticercosis (NCC) is the most likely cause of these lesions provided they fulfill a rigid set of clinical and radiological criteria. Single cysticercus granuloma measures less than 20 mm in diameter, may be associated with cerebral edema not severe enough to produce midline shift, and occur in patients with seizures, normal neurological status, and no evidence of active systemic disease. When these lesions resolve spontaneously, either disappearing or changing into a calcified nodule, the diagnosis of NCC is very likely. The second most common cause of these CT-detected lesions is tuberculoma; in patients with these lesions similar clinical and neuroimaging features are also present. Few authors believe that in poor and developing countries, where both tuberculosis and NCC are common, it is difficult to differentiate between tuberculoma and a single cysticercal granuloma. The most interesting feature of these solitary enhancing lesions is their spontaneous disappearance within weeks or months. Some lesions "heal" by becoming calcified. These patients require only antiepileptic therapy, and this medication may be withdrawn safely after the lesion has resolved on CT scanning. In several studies provision of anticysticercal drugs has been attempted, but because of conflicting results, their role in the management of these single lesions is uncertain. Neurosurgeons have a very limited role to play. In very rare situations, if the lesion increases in size and if focal neurological deficits manifest or seizures are uncontrolled, a brain biopsy sample may be required and histopathological evaluation performed to establish the correct diagnosis.

Detection of antigen B of Cysticercus cellulosae in cerebrospinal fluid for the diagnosis of human neurocysticercosis

Neurocysticercosis (NCC) is a major cause of morbidity and mortality in developed and developing countries. The diagnosis of this disease remains a problem. We report the detection of specific antigenic fraction (antigen B) of Cysticercus cellulosae by enzyme-linked immunosorbent assay (ELISA) in various fractions of cerebrospinal fluid (CSF) obtained by high performance liquid chromatographic (HPLC) separation, for the diagnosis of human NCC. Forty patients attending or admitted to Nehru Hospital, Chandigarh were included in the study: 10 with suspected NCC, 20 with other neurological diseases and 10 undergoing surgery under spinal anaesthesia for non-neurological conditions, who served as controls. CSF samples collected from all patients and controls were subjected to chromatographic separation on an HPLC system. Antigen B (AgB) was detected in separated fractions by an ELISA test and compared with the detection of antibody response in CSF samples by indirect haemagglutination (IHA) technique. Antigen B was detected in 9 out of 10 patients with suspected NCC based on clinical symptoms and radioimaging reports, but in none of the control subjects. However, antigen B was also detected in 9 out of 20 patients with other neurological disorders, mostly tubercular meningitis. Antibody response by IHA was found positive in only 2 of 10 cases clinically suspected of NCC. In conclusion, antigen B detection in CSF samples may be a useful adjunct to clinical suspicion and radiological reports for the diagnosis of NCC as there is no gold standard criteria to confirm this disease. However, the test needs to be evaluated on more patients in countries where tuberculosis and cysticercosis are endemic due to the high cross reactivity with samples from tubercular meningitis patients.

Single small enhancing computed tomographic (CT) lesions in Indian patients with new-onset seizures. A prospective follow-up in 75 patients

This study was planned to observe the clinical and radiological course of single small enhancing CT lesions in Indian patients presenting with new-onset-seizures. In this study, 75 patients with new-onset seizures and a single enhancing CT lesion were prospectively followed up for 1 year. All patients fulfilled the criteria of cysticercus granuloma. The repeat CT scans were performed 2 months after the first CT scan. Antiepileptic drug therapy was the only form of treatment given. The majority of patients were below 20 years of age. Simple partial seizure, with or without secondary generalization, was the commonest type of seizure encountered in these patients. In follow-up CT scans 84% of patients showed either disappearance or regression in the size of lesion. The proportion of patients showing complete disappearance of CT lesions was 0.73 (95% CI, 0.61-0.80). In 11 (15%) patients the lesions were calcified. In nine patients, in whom the lesion had persisted or regressed, another follow-up CT scan (6 months after the second scan) revealed either complete disappearance or calcification of the lesions. The majority (86.6%) of patients remained seizure free for 1 year after starting antiepileptic drugs. Ten patients experienced seizure recurrences within the first month of therapy. The proportion of patients who remained seizure free was 0.86 (95% CI, 0.76-0.92). Four patients experienced seizure recurrence even after complete disappearance of CT lesions. In the majority of patients the lesions disappeared spontaneously and in a few the lesions calcified; hence these patients did not require anticysticercal therapy. Antiepileptic therapy was helpful in controlling further recurrences of seizures in most of the patients. A few patients experienced seizures even after disappearance of CT lesions.

Cognitive Performance of Patients with Epilepsy and Calcified Neurocysticercotic Lesions: A Case-Control Study

Neuropsychological tests were applied to 20 patients with focal epilepsy related to calcified neurocysticercosis (NCC) (mean: three lesions/patient; NCC group), 22 patients with focal epilepsy without NCC (EPI group), and 29 healthy controls matched for age, sex, and educational level. The EPI and NCC groups were matched for age at onset of epilepsy, epilepsy duration, frequency of attacks, seizure semiology, interictal EEG findings, and antiepileptic drugs used. There were no differences in the digit span, word span, calculus, and Mini-Mental State examination among the three groups studied. The NCC and EPI groups showed lower scores than controls in immediate and delayed verbal memory, famous faces test, spatial recognition span, abstractions and judgment, and visuoconstructional abilities. The EPI group, but not the NCC group, also had lower scores in a praxis tests. There were no differences between the NCC and EPI groups in any of the tests applied (P > 15), except for the spatial recognition span, which was lower in the former. Cognitive impairment is a prevalent neuropsychological feature of patients with epilepsy and NCC.

Short regimen of praziquantel in the treatment of single brain enhancing lesions

Twenty-six patients with single enhancing brain lesion (SEL) were openly assigned to receive single-day praziquantel therapy (n=14), or not (n=12). From 14 treated patients, complete resolution was found in 11, partial resolution in two, and the remaining case was later diagnosed as an arteriovenous malformation. Side effects presented in only one patient and remitted in the same day with symptomatic treatment. Conversely, the lesions persisted unchanged in six of 12 patients in the non-treatment group. Untreated patients with persisting lesions were prescribed praziquantel treatment. After this, SELs disappeared in three cases, other diagnoses (brain tuberculoma and arteriovenous malformation) were made in two, and one was not evaluated. When analyzed in regard to the baseline serology, resolution of lesions on computed tomography was found in 13 (complete=12, partial=1) of 14 seropositive patients, whereas it only happened in six (complete=5, partial=1) of 12 seronegative patients. Serological screening defines a subset of SEL patients with good prognosis. If antiparasitic therapy is to be used in patients with SEL, and we cannot find a strong argument against it, single-day praziquantel is the regimen of choice based on duration, costs, and minimal side effects.

Risk of seizures and neurocysticercosis in household family contacts of children with single enhancing lesions

A small, single enhancing lesion (SEL) is often noted upon computed tomography (CT) in children and young adults with recent focal or generalized seizures. A high frequency of seizures has been reported in family members of persons with SEL. We studied the prevalence of seizures and cysticercus electro-immuno-transfer blot (EITB) based seropositivity among family members, specifically household family contacts of pediatric subjects with a SEL. An attempt was also made to determine the etiology of seizures in household family contacts using magnetic resonance imaging (MRI). Information regarding seizure semiology, personal and food habits and detailed family pedigrees was obtained from 20 consecutive pediatric subjects with a SEL and 51 of their household family contacts. EITB sero-assays and stool examinations were performed on all participating subjects. MRIs were done on all EITB positive household family contacts. A family history of seizures was obtained in six index children (30%) (five household first-degree relatives and two distant relatives). Seventeen index children (85%) and 14 family contacts (27%) were EITB positive. A tendency towards clustering of EITB positive cases within individual families was observed. Stool examinations did not reveal Taenia species ova in any of EITB positive subjects. Neuroimaging studies revealed abnormalities consistent with active or inactive neurocysticercosis in all five household family contacts with history of seizures. Four of these five subjects were EITB positive and one was EITB negative. We concluded that children with SEL and seizures may have a family history of seizures. There is a high seropositivity rate in household family contacts of pediatric subjects with solitary cysticercus granulomas (SCGs). EITB based seropositivity in household family contacts with seizures, strongly predicts a cysticercal etiology for seizures. It may be worthwhile to screen household family contacts of children with SEL for taeniasis-cysticercosis.

Focal cortical-subcortical calcifications (FCSCs) and epilepsy in the Indian subcontinent

PURPOSE

A focal cortical-subcortical calcification (FCSC) is a common finding on computed tomography (CT) in individuals with focal or generalized seizures in the Indian subcontinent. We sought to determine the relation of FCSCs to epilepsy by comparing the lobe of seizure origin by electroclinical and CT evaluations and to study the nature and severity of epilepsy associated with FCSCs.

METHODS

The relation of these FCSCs to epilepsy/seizures was studied in 40 patients, seen for the first time to the neurology outpatient department of a tertiary care hospital. An attempt was made to classify seizures and determine their lobe of origin based on clinical-electroencephalographic (EEG) criteria of the International League Against Epilepsy (ILAE). The clinical lobe of origin was compared with the location of the FCSC on CT scan. In addition, records of the CT unit of the same hospital were reviewed retrospecitvely, to identify cases with an FCSC and their referral diagnoses.

RESULTS

Thirty-one (77.5%) patients with FCSCs were considered to have localization-related epilepsy (frontal lobe epilepsy, 20; temporal lobe epilepsy, three; parietal lobe epilepsy, one; occipital lobe epilepsy, three; and definitely localization related but having ambiguous localization features, four) based on ictal semiology and EEG studies. Other ILAE categories in the cohort included epilepsy without unequivocal focal or generalized features (four patients; 10%), isolated seizures (one patient; 2.5%), juvenile absence epilepsy (one patient; 2.5%), and insufficient data to classify epilepsy (three patients; 7.5%). Radiologic sites for FCSCs included frontal (20; 50%), temporal (six; 15%), parietal (seven; 17.5%), and occipital (seven; 17.5%). Electroclinical and radiologic data were congruent in localizing and lateralizing seizures in 22 (55%) patients. The FCSC was truly incidental in one patient with juvenile absence epilepsy. Discordance between the clinical and radiologic localizations was noted in five (12.5%) instances. Magnetic resonance imaging (MRI) did not reveal additional lesions corresponding to lobes of origin as determined by electroclinical analysis. Discordance was surmised to be a result of seizure spread from a silent region to symptomatic cortex. In 12 (30%) patients, electroclinical and radiologic congruence could not be ascertained because ictal descriptions were either inadequate or ambiguous, and EEG findings were noncontributory. Review of 4,452 CT scans of brain performed in the CT unit revealed 29 (0.65%) cases with FCSCs in individuals with nonseizure disorders, that could be labeled as incidental.

CONCLUSIONS

An FCSC is an important radiologic finding in localization-related epilepsy in the Indian subcontinent. The severity of epilepsy ranges from asymptomatic cases to daily seizures.