Human case management and treatment of cysticercosis

Surgical nuances of giant neurocysticercosis according to intracranial location in the Southwest region of the Dominican Republic, presentation of cases, and literature review

BACKGROUND

Neurocysticercosis (NCC) is the most common infestation of the central nervous system, caused by the larval stage of the pig tapeworm Taenia solium. It is prevalent in regions with poor sanitation and underdevelopment, such as Latin America.

CASE DESCRIPTION

We present four cases in which they harbored an intraventricular/intraparenchymal, frontal convexity, cerebellomedullary, and intraparenchymal NCC cyst of medium size, respectively. Three of them underwent complete removal of the cyst by craniotomy; the fourth had a shunt for obstructive hydrocephalus first, followed by excision of a suboccipital cyst 8 months later.

CONCLUSION

The intraventricular/intraparenchymal lesion was more complex to treat than its subarachnoid counterparts because the average brain should be transected and dissected away to achieve total removal. Waterjet dissection, arachnoid microdissection, and cyst drainage allowed minor brain damage than capsule coagulation and traction. Populated prospective studies are needed better to understand the surgical nuances of these rare entities.

Surgical nuances of giant neurocysticercosis according to intracranial location in the Southwest region of the Dominican Republic, presentation of cases, and literature review

Background:

Neurocysticercosis (NCC) is the most common infestation of the central nervous system, caused by the larval stage of the pig tapeworm Taenia solium. It is prevalent in regions with poor sanitation and underdevelopment, such as Latin America.

Case Description:

We present four cases in which they harbored an intraventricular/intraparenchymal, frontal convexity, cerebellomedullary, and intraparenchymal NCC cyst of medium size, respectively. Three of them underwent complete removal of the cyst by craniotomy; the fourth had a shunt for obstructive hydrocephalus first, followed by excision of a suboccipital cyst 8 months later.

Conclusion:

The intraventricular/intraparenchymal lesion was more complex to treat than its subarachnoid counterparts because the average brain should be transected and dissected away to achieve total removal. Waterjet dissection, arachnoid microdissection, and cyst drainage allowed minor brain damage than capsule coagulation and traction. Populated prospective studies are needed better to understand the surgical nuances of these rare entities.

Solitary cysticercus in the right temporalis muscle: case report of a rare form of presentation of cysticercosis

Solitary cysticercus localized to the head and neck musculature is an unusual form of presentation of cysticercosis. Since it is rare and has non-specific manifestations, it can present a diagnostic challenge to the clinician. Our patient was a 16-year-old female who presented with a gradually increasing, painful swelling over right temple region of 6-month duration. Ultrasound and computed tomography scan revealed the presence of a solitary cysticercus in the right temporalis muscle. Surgical excision of the lesion was combined with a 4-week course of the anti-helminthic drug, Albendazole. Patient had a satisfactory resolution of symptoms and there was no recurrence in a follow-up period of 3 years. We suggest that cysticercosis should be considered as one of the possibilities in the differential diagnosis of swellings in the maxillofacial region, especially in the endemic areas. Imaging studies play an important role in confirmation of the diagnosis.

TNF-α blockade suppresses pericystic inflammation following anthelmintic treatment in porcine neurocysticercosis

Background

Neurocysticercosis (NCC) is an infection of the brain with the larval cyst of the tapeworm, Taenia solium. Cysticidal treatment induces parasite killing resulting in a post inflammatory response and seizures, which generally requires corticosteroid treatment to control inflammation. The nature of this response and how to best control it is unclear. We investigated the anti-inflammatory effects of pretreatment with etanercept (ETN), an anti-tumor necrosis factor agent, or dexamethasone (DEX), a high potency corticosteroid, on the post treatment inflammatory response in naturally infected pigs with neurocysticercosis after a single dose of the cysticidal drug praziquantel (PZQ).

Methodology/Principal findings

We followed the methods from a previously developed treatment model of NCC in naturally infected swine. The four study groups of infected pigs included 3 groups treated with PZQ on day 0: PZQ-treated alone (100 mg/kg PO; n = 9), pretreated with dexamethasone (DEX, 0.2 mg/kg IM administered on days -1, +1 and +3; n = 6), and pretreated with etanercept (ETN, 25 mg IM per animal on days -7 and 0; n = 6). The fourth group remained untreated (n = 3). As measured by quantitative RT-PCR, ETN pretreatment depressed transcription of a wide range of proinflammatory, regulatory and matrix protease encoding genes at 120 hr post PZQ treatment in capsules of cysts that demonstrated extravasated Evans Blue (EB) (a measure of blood brain barrier dysfunction) compared to animals not receiving ETN. Transcription was significantly depressed for the proinflammatory genes tumor necrosis factor (TNF)-α, and interferon (IFN)-γ; the inflammation regulating genes cytotoxic T-lymphocyte-associated protein (CTLA)4, interleukin (IL)-13 and transforming growth factor (TGF)-β; the tissue remodeling genes matrix metalloprotease (MMP)1 and 9, tissue inhibitors of metalloproteases (TIMP)1 and 2, and the genes regulating endothelial function vascular endothelial growth factor (VEGF)1, angiopoietin (Ang)1, Ang 2, and platelet endothelial cell adhesion molecule (PECAM)-1. In contrast, transcription was only modestly decreased in the DEX pretreated pigs compared to PZQ alone, and only for TNF-α, IL-6, IFN-γ, TGF-β and Ang1. IL-10 was not affected by either ETN or DEX pretreatments. The degree of inflammation, assessed by semi-quantitative inflammatory scores, was modestly decreased in both ETN and DEX pretreated animals compared to PZQ treated pigs whereas cyst damage scores were moderately decreased only in cysts from DEX pretreated pigs. However, the proportion of cysts with EB extravasation was not significantly changed in ETN and DEX pretreated groups.

Conclusions/Significance

Overall, TNF-α blockade using ETN treatment modulated expression of a large variety of genes that play a role in induction and control of inflammation and structural changes. In contrast the number of inflammatory cells was only moderately decreased suggesting weaker effects on cell migration into the inflammatory capsules surrounding cysts than on release of modulatory molecules. Taken together, these data suggest that TNF-α blockade may provide a viable strategy to manage post-treatment pericystic inflammation that follows antiparasitic therapy for neurocysticercosis.

Infection of the brain with larvae of the tapeworm Taenia solium is called neurocysticercosis (NCC), a disease with varied and serious neurological symptoms. Therapy requires antiparasitic drugs and corticosteroids to prevent seizures caused by treatment due to inflammation around dying parasites. The gene expression of the proinflammatory molecule tumor necrosis factor alpha (TNF-α) is increased in NCC. We treated three groups of naturally infected pigs with an antiparasitic drug: one group was also pretreated with an anti-TNF-α inhibitor, the second one with a corticosteroid, and the third was not pretreated. All pigs were infused with Evans blue dye (EB), which leaks where the blood brain barrier is damaged by inflammation around cysts. We compared the expression of several genes involved in inflammation, healing and fibrosis and regulation of vascular function in tissues surrounding cysts. In inflamed samples showing leaked EB, the inhibition of TNF-α suppressed nearly all the genes assessed, and this suppression was significantly stronger than the moderate decrease caused by corticosteroid pretreatment on most of the genes. On microscopic examination, the inflammation observed was slightly decreased with both pretreatments in relation to the group that was not pretreated. We believe that the inflammatory route that includes TNF-α should be further explored in the search for better management of inflammation directed to degenerating cysts.

Orofacial cysticercosis: Report of a rare case with review of literature

Cysticercosis is common in developing countries in which the combination of rural society, crowding, and poor sanitation facilities allows greater contact between humans and pigs and thus more opportunities for fecal contamination of food and water occurs. They are rarely located in oral and perioral tissues, particularly in the muscles of mastication, muscle of the facial expression, suprahyoid muscles, and postcervical musculature and also as in the tongue, buccal mucosa, and lip. Cysticercosis is a potentially fatal parasitic disease that rarely found in the maxillofacial region in humans. This paper reports the case of a young female patient presented with isolated lesion of cysticercosis involving buccinator muscle. In conclusion, we suggest that cysticercosis should be considered in the differential diagnosis of intraoral solitary nodules within the oral and maxillofacial region, especially in endemic areas. High-resolution ultrasonography is an excellent noninvasive and cost-effective modality for the diagnosis and also suggests that localized parasitic infections such as Cysticercus cellulosae can be successfully treated with conservative management using oral antiparasitic (antihelminthic) medication.

Post-treatment vascular leakage and inflammatory responses around brain cysts in porcine neurocysticercosis

Cysticidal treatment of neurocysticercosis, an infection of humans and pig brains with Taenia solium, results in an early inflammatory response directed to cysts causing seizures and focal neurological manifestations. Treatment-induced pericystic inflammation and its association with blood brain barrier (BBB) dysfunction, as determined by Evans blue (EB) extravasation, was studied in infected untreated and anthelmintic-treated pigs. We compared the magnitude and extent of the pericystic inflammation, presence of EB-stained capsules, the level of damage to the parasite, expression of genes for proinflammatory and regulatory cytokines, chemokines, and tissue remodeling by quantitative PCR assays between treated and untreated infected pigs and between EB-stained (blue) and non stained (clear) cysts. Inflammatory scores were higher in pericystic tissues from EB-stained cysts compared to clear cysts from untreated pigs and also from anthelmintic-treated pigs 48 hr and 120 hr after treatment. The degree of inflammation correlated with the severity of cyst wall damage and both increased significantly at 120 hours. Expression levels of the proinflammatory genes for IL-6, IFN-γ, TNF-α were higher in EB-stained cysts compared to clear cysts and unaffected brain tissues, and were generally highest at 120 hr. Additionally, expression of some markers of immunoregulatory activity (IL-10, IL-2Rα) were decreased in EB-stained capsules. An increase in other markers for regulatory T cells (CTLA4, FoxP3) was found, as well as significant increases in expression of two metalloproteases, MMP1 and MMP2 at 48 hr and 120 hr post-treatment. We conclude that the increase in severity of the inflammation caused by treatment is accompanied by both a proinflammatory and a complex regulatory response, largely limited to pericystic tissues with compromised vascular integrity. Because treatment induced inflammation occurs in porcine NCC similar to that in human cases, this model can be used to investigate mechanisms involved in host damaging inflammatory responses and agents or modalities that may control damaging post treatment inflammation.

Neurocysticercosis is caused by infection of the brain with the larval (cyst) stage of the tape worm Taenia solium in humans and pigs. Antiparasitic drug treatment is compromised by worsening of neurological symptoms during therapy due to reactive inflammation triggered by the dying parasite. The immune mechanisms that cause this inflammation are poorly understood. In this study, we investigated the nature of inflammation after treatment in pigs naturally infected with T. solium cysts. Evans blue dye injected into infected pigs marks areas in the brain where the normally impermeable capillaries have become more permeable, allowing damaging cells and molecules to leak out into the brain. By microscopy and measurement of gene expression for inflammation-inducing immune mediators, we show that inflammation in the brain tissues around cysts is more severe with increased vessel leakage. Furthermore, the levels of these mediators increased after antiparasitic drug treatment. A significant implication of these findings is that it may be possible to inhibit the inflammation around parasites using drugs or biologics that inhibit these inflammatory pathways and, thereby, reduce local brain damage during treatment. These observations may also be applicable to other inflammatory conditions that affect the brain.

Solitary Cysticercosis of the Temporalis Muscle: Report of a Rare Case

Patient presented with swelling over right temporal region causing the dilemma over diagnosis. Sonography and CT scan confirmed the presence of cysticercus in right temporal region. Pharmacological management was instituted and the cyst resolved eventually. Ultrasonography and CT imaging play an important role in establishing the diagnosis of rare case of cysticercosis of temporalis muscle and can be treated successfully by pharmacological modality.

Neurocysticercosis: an update

Neurocysticercosis (NCC) is the most common helminthic disease of the nervous system in humans and a major cause of acquired epilepsy worldwide. The presentation of the disease is dependent on both the immunological response of the host against the parasite as well as the location of the encysted organisms within the central nervous system (CNS). The principles of management utilized for intraparenchymal disease cannot be applied to extraparenchymal NCC. An advance in management of intraparenchymal NCC, the most common form encountered by physicians, is the use of both albendazole and praziquantel as a treatment strategy. Patients with subarachnoid NCC (SANCC) require months of treatment with both an antiparasitic agent and steroids to avoid complications such as hydrocephalus and vascular events during treatment. The determinants of successful treatment in SANCC have not been established, but response to therapy can be determined by evaluating several endpoints related to disease evolution including radiographic changes, serum antigen, and CSF antigen. Intraventricular NCC is primarily a surgical disease and data supports minimally invasive endoscopic removal of cysts in many of these patients. NCC is increasingly recognized in non-endemic countries due to increased immigration making it important for physicians to become familiar with the management of this disease.

Comparative profile of circulating antigenic peptides in CSF, serum & urine from patients with neurocysticercosis diagnosed by immunoblotting

Traditionally serum and/or CSF specimens have been used for detection of either specific antibodies or antigens as a supportive diagnosis of NCC. However, in recent days, much interest has been shown employing noninvasive specimens such as urine. In our study, we identified and compared a profile of circulating antigenic peptides of parasite origin in three different body fluids (CSF, serum and urine) obtained from confirmed NCC cases and control subjects. The circulating antigenic peptides were resolved by SDS-PAGE and subjected to immunoblotting. For confirmation of their origin as parasite somatic or excretory secretory (ES) material, immunoreactivity was tested employing affinity purified polyclonal Taenia solium metacestode anti-somatic or ES antibodies, respectively. Only lower molecular weight antigenic peptides were found circulating in urine in contrast to serum and CSF specimens. Few somatic peptides were identified to be 100% specific for NCC (19·5 kDa in all three specimens; 131, 70 kDa in CSF and serum only; 128 kDa in CSF only). Similarly, the specific ES peptides detected were 32 kDa (in all three specimens), 16·5 kDa (in serum and CSF only), and 15 kDa (urine only). A test format detecting either one or more of these specific peptides would enhance the sensitivity in diagnosis of NCC.

Evans blue staining reveals vascular leakage associated with focal areas of host-parasite interaction in brains of pigs infected with Taenia solium

Cysticidal drug treatment of viable Taenia solium brain parenchymal cysts leads to an acute pericystic host inflammatory response and blood brain barrier breakdown (BBB), commonly resulting in seizures. Naturally infected pigs, untreated or treated one time with praziquantel were sacrificed at 48 hr and 120 hr following the injection of Evans blue (EB) to assess the effect of treatment on larval parasites and surrounding tissue. Examination of harvested non encapsulated muscle cysts unexpectedly revealed one or more small, focal round region(s) of Evans blue dye infiltration (REBI) on the surface of otherwise non dye-stained muscle cysts. Histopathological analysis of REBI revealed focal areas of eosinophil-rich inflammatory infiltrates that migrated from the capsule into the tegument and internal structures of the parasite. In addition some encapsulated brain cysts, in which the presence of REBI could not be directly assessed, showed histopathology identical to that of the REBI. Muscle cysts with REBI were more frequent in pigs that had received praziquantel (6.6% of 3736 cysts; n = 6 pigs) than in those that were untreated (0.2% of 3172 cysts; n = 2 pigs). Similar results were found in the brain, where 20.7% of 29 cysts showed histopathology identical to muscle REBI cysts in praziquantel-treated pigs compared to the 4.3% of 47 cysts in untreated pigs. Closer examination of REBI infiltrates showed that EB was taken up only by eosinophils, a major component of the cellular infiltrates, which likely explains persistence of EB in the REBI. REBI likely represent early damaging host responses to T. solium cysts and highlight the focal nature of this initial host response and the importance of eosinophils at sites of host-parasite interaction. These findings suggest new avenues for immunomodulation to reduce inflammatory side effects of anthelmintic therapy.

Therapy for neurocysticercosis

Therapy for neurocysticercosis has advanced during the last 20 years with the advent of albendazole (Zentel) and praziquantel (Cysticide). Albendazole is the current medication of choice for the treatment of neurocysticercosis and is recommended for symptomatic patients with multiple viable cysts in the brain parenchyma. Albendazole may also be useful in extraparenchymal cysticercosis, especially in the subarachnoid racemose form, when complete surgical resection of the cysts is usually impracticable. Currently, there is an intense debate over the value and safety of anticysticercal therapy. Causes for failure of anticysticercal therapy include high inter-individual variability in plasma concentration of albendazole sulfoxide and the complex interactions of several drugs with the albendazole metabolite. Furthermore, albendazole sulfoxide is an enantiomeric mixture of (+)- and (-)-albendazole sulfoxide with accumulation of the (+)-enantiomer in the cerebrospinal fluid. However, the question over which enantiomer is effective against cysticerci remains to be clarified.

Prevalence and risk factors associated with human Taenia solium infections in Mbozi District, Mbeya Region, Tanzania

Background

Taenia solium cysticercosis/taeniosis is emerging as a serious public health and economic problem in many developing countries. This study was conducted to determine prevalence and risk factors of human T. solium infections in Mbeya Region, Tanzania.

Methods and Findings

A cross-sectional survey was conducted in 13 villages of Mbozi district in 2009. Sera of 830 people (mean 37.9±11.3 years (SD); 43% females) were tested for circulating cysticerci antigen (Ag-ELISA) and antibody (Ab-ELISA). A subset of persons found seropositive by Ag-ELISA underwent computed tomography (CT) scan of the brain for evidence of neurocysticercosis. Stool samples from 820 of the same participants were tested for taeniosis by copro-antigens (copro-Ag-ELISA) and formol-ether concentration technique. Cases of T. solium taeniosis were confirmed serologically by EITB assay (rES38). A questionnaire was used for identification of risk factors. Active cysticercosis by positive Ag-ELISA was found in 139 (16.7%) persons while anti-cysticercal antibodies were detected in 376 (45.3%) persons by Ab-ELISA. Among 55 persons positive for Ag-ELISA undergoing CT scan, 30 (54.6%) were found to have structures in the brain suggestive of neurocysticercosis. Using faecal analysis, 43 (5.2%) stool samples tested positive for taeniosis by copro-Ag-ELISA while Taenia eggs were detected in 9 (1.1%) stool samples by routine coprology. Antibodies specifically against adult T. solium were detected in 34 copro-Ag-ELISA positive participants by EITB (rES38) indicating T. solium taeniosis prevalence of 4.1%. Increasing age and hand washing by dipping in contrast to using running water, were found associated with Ag-ELISA seropositivity by logistic regression. Gender (higher risk in females) and water source were risk factors associated with Ab-ELISA seropositivity. Reported symptoms of chronic severe headaches and history of epileptic seizures were found associated with positive Ag-ELISA (p≤0.05).

Conclusion

The present study indicates T. solium infection in humans is highly endemic in the southern highlands of Tanzania.

Cysticercosis caused by the zoonotic pork tapeworm, Taenia solium, is emerging as a serious public health and agricultural problem in sub-Saharan Africa. Surveys have shown cysticercosis in pigs to be highly prevalent in multiple foci in Tanzania, and a hospital-based study in the northern highlands indicated neurocysticercosis as an important cause of epileptic seizures in humans. We present here a cross-sectional community-based survey on the prevalence and risk factors of human cysticercosis and taeniosis conducted in the southern highlands – the major pig-producing area of the country. The most striking findings were that more than 15% of people surveyed were found to have active cysticercosis and nearly half of them were found to have been exposed to larval T. solium indicating a high level of environmental contamination with T. solium eggs. This was supported by finding over 4% of people having had T. solium tapeworms. A subset of persons found positive serologically for active cysticercosis underwent brain scanning and more than half of them were found to have neurocysticercosis. This strong evidence that T. solium cysticercosis/neurocysticercosis/taeniosis is highly endemic in the southern highlands of Tanzania demands urgent attention of regional and national authorities to combat the parasite.

Albendazole therapy for coagulation abnormality in children with eosinophilia

Hemorrhage may be associated with eosinophilia. Here, 2 pediatric cases of coagulation abnormality were reported. The 2 children presented ecchymoses and petechiae in the skin. Laboratory investigations revealed hypereosinophilia in the peripheral blood. Moreover, the activity of coagulation factor IX significantly decreased. The serum immunoglobulin G (IgG) antibody to cysticercus was positive in patient 1, and IgG antibodies to cysticercus and plerocercoid were positive in patient 2. These 2 patients received 2 courses of albendazole therapy, at 15 mg/kg/day in divided doses for 10 days for each course. They responded well to the therapy. This report indicates that patients with hypereosinophilia and bleeding abnormalities should undergo evaluation of coagulation pathways, including measurements of coagulation factors.

Sensitive in vitro system to assess morphological and biochemical effects of praziquantel and albendazole on Taenia solium cysts

Neurocysticercosis resulting from Taenia solium infections is a major cause of adult-acquired seizures worldwide. Disease is caused by larval cysts, and treatment consists of the anthelmintic drugs albendazole or praziquantel. There are no standard methods to assess drug activity to T. solium cysts in vitro. Morphological, functional, and biochemical changes that might reflect damaging (inhibiting, cytotoxic) drug effects were analyzed after exposure of cysts to albendazole sulfoxide (ABZ-SO), the major active metabolite of the drug in vivo, praziquantel (PZQ), or combinations of both. PZQ exposure led to a decrease in cyst size and inhibition of evagination, whereas ABZ-SO exposure resulted in minimal changes. Alkaline phosphatase (AP) is normally secreted by cysts, and both drugs inhibited AP secretion at concentrations of 5 and 50 ng/ml for PZQ and ABZ-SO, respectively. Some combinations of both drugs resulted in additive and/or synergistic activities. Parasite-specific antigen, detected in the cerebrospinal fluid and blood of infected patients, is also normally secreted by T. solium cysts. Antigen secretion was similarly inhibited by ABZ-SO and PZQ and a combination of both drugs, suggesting that inhibition of secretion is a common downstream consequence of the activities of both drugs. These studies establish quantitative methods to measure in vitro anthelmintic activity and suggest combination therapy with ABZ-SO and PZQ may have clinical benefit.

Treatment of neurocysticercosis: is it beneficial?

Neurocysticercosis is the most common parasitic disease of the CNS. Intracranial neurocysticercosis is classified into cerebral parenchymal and extraparenchymal forms (subarachnoidal and intraventricular). Current medical therapy for parenchymal and extraparenchymal neurocysticercosis invovles the use of anticysticercal drugs. Albendazole and praziquantel are two commonly used drugs. Most experts prefer to always use oral or parenteral corticosteroids along with anticysticercal drugs. The role of anticysticercal drugs in the treatment of parenchymal neurocysticercosis has always been a subject of intense controversy. Whether therapy with anticysticercal drugs results in improved seizure-related prognosis remains a major concern. A recent meta-analysis evaluating six controlled trials suggests that treatment with anticysticercal drugs results in better resolution of colloidal and vesicular cysticerci; in patients taking anticysticercal drugs, there was a lower risk of seizure reccurence in patients with colloidal cysticerci and a significant reduction in the rate of generalized seizures in patients with vesicular cysticerci. However, the findings of the study by Carpio et al. have revived the controversy regarding this treatment. These authors noted that the effect of a single dose of albendazole is, at best, only modest. Only a minority of patients with parenchymal neurocysticercosis benefitted and became cyst free and there was a lack of effectiveness toward the associated seizure disorders. No response was seen in patients with degenerative parenchymal or extraparenchymal forms of neurocysticercosis. Carpio et al. suggest that there is a need for further studies that employ different approaches, such as the use of high initial doses of albendazole, the use of two anticysticercal drugs or repeated prolonged courses of albendazole.

Orbital cysticercosis: diagnosis and treatment controversies

Orbital cysticercosis is a rare condition and its management is controversial. We report 2 cases of orbital cellulitis associated with cysticercosis in which the treatment with antihelminthics was withheld. The 2 children had good evolution with spontaneous progressive resolution. The current literature is reviewed.

Methotrexate as a corticosteroid-sparing agent in complicated neurocysticercosis

BACKGROUND

A subset of patients with neurocysticercosis developed chronic or recurrent perilesional inflammation and required long-term and high-dose corticosteroid therapy. Such therapy frequently results in severe adverse effects. The purpose of this study was to determine whether methotrexate can be used as an effective corticosteroid-sparing or replacement agent in patients with complicated neurocysticercosis.

METHODS

This study was a nonblinded, prospective, observational trial. Patients with neurocysticercosis who required prednisone (15 mg/day) or its equivalent for > or =2 months, were likely to require long-term corticosteroid therapy by nature of their disease, developed serious complications due to corticosteroid use, or presented with a long-term history of corticosteroid use and had continued evidence of ongoing inflammation were eligible for methotrexate treatment.

RESULTS

Four patients are described in this study: 2 with subarachnoid neurocysticercosis, 1 with severe intraventricular and parenchymal disease, and 1 with recurrent perilesional edema around calcified lesions. Chronic inflammation due to neurocysticercosis resulted in lacunar infarcts, visual impairment, hydrocephalus, and seizures in these patients and necessitated long-term treatment with corticosteroids, which resulted in multiple adverse effects. The addition of methotrexate, prescribed at < or =20 mg/week, allowed for the successful reduction of corticosteroid use in all 4 patients and resulted in the improvement of many corticosteroid-associated adverse effects.

CONCLUSIONS

Methotrexate is a beneficial corticosteroid-sparing or replacement agent for patients with neurocysticercosis who develop chronic or recurrent perilesional inflammation.

Taenia coenurus in the orbit of a chinchilla

A 4-year old, male intact, captive-bred chinchilla (Chinchilla lanigera) was presented due to progressive exophthalmos of the right eye over a 5-month period. Ophthalmic examination revealed exophthalmos with dorsal displacement of the right globe. Retropulsion was decreased and a fluctuant, subcutaneous mass could be palpated posterior and dorsal to the central aspect of the zygomatic bone. Transdermal ultrasonography revealed a fluid-filled mass consistent with a cyst located within the ventral right orbit. Computed tomography demonstrated dorsal displacement of the globe, lateral displacement of the zygomatic arch, and numerous mineral-dense foci within the lumen of the cyst. The cyst was removed en bloc by ventral transpalpebral orbitotomy. Histopathology revealed a single capsulated cyst with multiple invaginated protoscolices, characterized by a prominent scolex with refractile hooklets, suckers, and abundant calcareous corpuscles consistent with a Taenia coenurus. Exophthalmos resolved with surgical therapy and there was no evidence of recurrence or postoperative complications over a period of 2 years. To the authors' knowledge, this is the first reported case of an orbital cyst of parasitic origin in a chinchilla.

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.

Bilateral disk edema with unilateral macular serous fluid secondary to neurocysticercosis

PURPOSE

The purpose of this article is to document a case of neurocysticercosis that manifested clinically with bilateral disk edema and serous fluid accumulation in the macula of the left eye. We also describe the recovery of visual-field loss (O.D.) and diminution of bilateral disk edema following anti-helminthic treatment.

CASE REPORT

A 41-year-old woman reporting headaches came to us with bilateral disk edema and co-existing serous macular fluid in the left eye.

RESULTS

Magnetic resonance imaging (MRI) revealed the presence of large multi-septated cysts that exhibited peripheral enhancement, with minimal surrounding edema at the posterior left temporal lobe. Scattered punctate lesions, suggesting areas of calcification, were also observed within both temporal lobes. The optic chiasm appeared compressed. This presentation was considered characteristic of neurocysticercosis and the patient was prescribed a regimen of 200mg albendazole b.i.d. The patient responded well to the treatment, with progressive resolution of the bilateral disk edema and macular fluid.

CONCLUSION

Although rare, cases of cysticercosis and neurocysticercosis may still be encountered in industrialized nations, where the parasite has been almost eradicated. Ocular signs of disk edema and macular serous fluid secondary to neurocysticercosis may correspond to optic nerve, parenchymal, or extraparenchymal disease.

The current status of neurocysticercosis in Eastern and Southern Africa

Some information has been documented on the epidemiology of neurocysticercosis in Eastern and Southern Africa through the monitoring of hospital-based patients with neurocysticercosis, community-based serological surveys of particular socio-economic groups of people and surveys of porcine cysticercosis. Studies have revealed that non-pork eaters have as great a chance of infection as a pork eater, the Xhosa-speaking people of the Eastern Cape Province have the highest prevalence of cysticercosis/taeniosis in South Africa probably due to the common practice of free-range pig farming and the lack of sanitation in these areas. Several studies have revealed high prevalence rates in children and interestingly, patients with active cysts suffering from epilepsy. A startling mode of transmission is where self-trained healers use Taenia segments either for benevolent (e.g. in the treatment of severe intestinal tapeworm infections) or malevolent (evil) purposes (e.g. women "poisoning" an unfaithful husband or lover by adding the contents of Taenia solium segments to beer).