Therapy of parenchymal brain cysticercosis with praziquantel

Neurocysticercosis: A Review into Treatment Options, Indications, and Their Efficacy

Neurocysticercosis, due to the localization of Taenia solium larvae in the Central Nervous System, is a neglected tropical disease still endemic in much of Latin America, Asia and sub-Saharan Africa. The therapeutic management of NC has gradually improved with the establishment of neuroimaging studies (CT and MRI) in endemic countries and with the demonstration of the efficacy of albendazole and praziquantel in the 1980s. But the morbidity and mortality of this preventable disease remain an unacceptable fact. In this scoping review, we will revise the different treatment options and their indications.

Neurocysticercosis research in Mexico: A bibliometric analysis of the Instituto Nacional de Neurología y Neurocirugía Manuel Velasco Suárez

Neurocysticercosis (NCC) is the most common neglected parasitic disease of the central nervous system and leads to many economic and health issues in endemic and non-endemic countries. A bibliometric analysis would shed light on the evolution and development of research in this field, and this is the first study on NCC research. Our institution in Mexico City, the Instituto Nacional de Neurología y Neurocirugía Manuel Velasco Suárez (INNN), has set some milestones in the management of neurocysticercosis and has a decade-long experience and such an analysis in an endemic country like Mexico will be beneficial. We tracked the scientific output in Scopus, from its foundation to March 2021. The studied variables were article type, number of citations, area (clinical/experimental), chronological profile, and preferred journals. In the period from 1964 to 2021, from a total of 3,166 articles from the institution, 232 papers are related to neurocysticercosis with a total of 7,155 citations. The trending topics in the clinical area are pharmacology and pathology in the experimental papers. The number of articles has steadily increased, but NCC is currently a neglected topic that needs further research to better address the disease burden and allow its eradication.

Neurocysticercosis. A frequent cause of seizures, epilepsy, and other neurological morbidity in most of the world

Neurocysticercosis is endemic in most of the world and in endemic areas it accounts for approximately 30% of cases of epilepsy. Appropriate diagnosis and management of neurocysticercosis requires understanding the diverse presentations of the disease since these will vary in regards to clinical manifestation, sensitivity of diagnostic tests, and most importantly, therapeutic approach. This review attempts to familiarize tropical neurology practitioners with the diverse types of neurocysticercosis and the more appropriate management approaches for each.

Rare Diseases of the Orbit

This article provides an overview of rare orbital diseases. Congenital malformations, inflammatory diseases, benign and malignant neoplasias are described. Although it represents a relatively small area of the body the orbit contains multiple different tissues. Therefore, a great variety of diseases can be found within the orbital space. That is the reason, why both the completeness and the level of detail in the description of particular diseases must be somewhat limited. Nevertheless, clinical manifestations, important aspects of diagnosis, treatment strategies, and, when specific data are available, the prognosis are described. The authors tried to highlight the most characteristic aspects of the different diseases to describe their relevant aspects in spite of the brevity of the subsections.

Inflammation in neurocysticercosis: clinical relevance and impact on treatment decisions

INTRODUCTION

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

AREAS COVERED

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

EXPERT OPINION

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

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.

A Personal Account Regarding the Origin and Evolution of Controversies in the Management of Neurocysticercosis

A panel of experts from the Infectious Disease Society of America and The American Society of Tropical Medicine and Hygiene recently published guidelines for management of neurocysticercosis, showing that clinical manifestations as well as the stage of involution and the anatomical location of parasites must be taken into account before the start of a rational therapy. Soon thereafter, isolated opinions attempted to discredit these guidelines, arguing insufficient or inadequate evidence and suggesting that they should not be followed worldwide. In view of these conflicting reports, it is appropriate to review the origin and evolution of the controversy on the medical treatment of neurocysticercosis.

Pharmacokinetics, Safety, and Tolerability of Oxfendazole in Healthy Volunteers: a Randomized, Placebo-Controlled First-in-Human Single-Dose Escalation Study

Cysticercosis is a parasitic disease that frequently involves the human central nervous system (CNS), and current treatment options are limited. Oxfendazole, a veterinary medicine belonging to the benzimidazole family of anthelmintic drugs, has demonstrated substantial activity against the tissue stages of Taenia solium and has potential to be developed as an effective therapy for neurocysticercosis. To accelerate the transition of oxfendazole from veterinary to human use, the pharmacokinetics, safety, and tolerability of oxfendazole were evaluated in healthy volunteers in this phase 1 first-in-human (FIH) study. Seventy subjects were randomly assigned to receive a single oral dose of oxfendazole (0.5, 1, 3, 7.5, 15, 30, or 60 mg oxfendazole/kg body weight) or placebo and were followed for 14 days. Blood and urine samples were collected, and the concentrations of oxfendazole were measured using a validated ultraperformance liquid chromatography mass spectrometry method. The pharmacokinetic parameters of oxfendazole were estimated using noncompartmental analysis. Oxfendazole was rapidly absorbed with a mean plasma half-life ranging from 8.5 to 11 h. The renal excretion of oxfendazole was minimal. Oxfendazole exhibited significant nonlinear pharmacokinetics with less than dose-proportional increases in exposure after single oral doses of 0.5 mg/kg to 60 mg/kg. This nonlinearity of oxfendazole is likely due to the dose-dependent decrease in bioavailability that is caused by its low solubility. Oxfendazole was found to be well tolerated in this study at different escalating doses without any serious adverse events (AEs) or deaths. There were no significant differences in the distributions of hematology, biochemistry, or urine parameters between oxfendazole and placebo recipients. (This study has been registered at ClinicalTrials.gov under identifier NCT02234570.).

The Role of Neurosurgery in the Treatment of Intracranial Tumor-Like Inflammatory Lesions

BACKGROUND

Different inflammatory diseases can manifest as intracranial lesions. They may be indistinguishable from intracranial neoplasms in the clinical setting, imaging studies, or laboratory studies. The value of surgery in the diagnosis and the treatment of such lesions is still unclear.

METHODS

A total of 3066 reports of histopathologic examinations over a 10-year period were reviewed. Forty patients with an inflammatory intracranial lesion were identified. Clinical, radiologic, and follow-up data were analyzed and the diagnostic and therapeutic value of surgery was assessed.

RESULTS

We identified 24 women and 16 men (mean age, 47 years). The diameter of the lesion varied between 1 and 5.5 cm (mean, 2.6 cm). The location of the inflammatory lesion was intracerebral supratentorial (n = 18, 45%), intrasellar/suprasellar (n = 5, 12.5%), cerebellar (n = 5, 12.5%), in the brainstem (n = 4, 10%), in the cerebellopontine angle (n = 3, 7.5%), meningeal (n = 3, 7.5%), and at other locations (n = 6, 15%). Seventeen patients underwent surgical removal of the mass lesion, whereas in 23 patients a biopsy was taken. The lesions were classified into 7 groups: specific (infectious) granuloma (n = 10, 25%), unspecific granuloma (n = 7, 17.5%), idiopathic inflammatory pseudotumor (n = 5, 12.5%), demyelinating lesions (n = 5, 12.5%) encapsulated hematoma (n = 4, 10%), organized cerebral infarction (n = 3, 7.5%), and vasculitis (n = 4, 10%). Surgery was judged as valuable in 35 patients (87.5%).

CONCLUSIONS

The differential diagnosis of intracranial inflammatory lesions involves a wide spectrum. Surgery has a diagnostic and/or therapeutic value in most entities and clinical circumstances. However, attention must be taken to avoid surgery without a therapeutic or diagnostic value for the patient.

Rare Orbital Infections ~ State of the Art ~ Part II

Infections of the orbit and periorbita are relatively frequent. Identifying unusual organisms is crucial because they can cause severe local and systemic morbidity, despite their rarity. Opportunistic infections of the orbit should be considered mainly in debilitated or immunocompromised patients. The key to successful management includes a high index of suspicion, prompt diagnosis, and addressing the underlying systemic disease. This review summarizes unusual infectious processes of the orbit, including mycobacterial, fungal, and parasitic infections, as well as their pathophysiology, symptoms, signs, and treatment.

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.

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: 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.

Neurocysticercosis

Neurocysticercosis, the most common helminthic infection of the nervous system, is a major cause of acquired epilepsy worldwide. The disease occurs when humans become intermediate hosts of the tapeworm Taenia solium after ingesting its eggs by contagion from an asymptomatic Taenia carrier. Within the nervous system, parasites may locate in brain parenchyma, subarachnoid space, ventricular system, or spinal cord, causing several pathological changes that are responsible for the clinical pleomorphism of the disease. Seizures are the most common clinical manifestation, but a sizable proportion of patients develop focal deficits, intracranial hypertension, or cognitive decline. Preoperative diagnosis of neurocysticercosis is possible after proper integration of data from neuroimaging studies and immunological tests. Cysticidal drugs (albendazole and praziquantel) have changed the prognosis of most patients with neurocysticercosis. The use of these drugs has shown to reduce the parasite load within the central nervous system and to improve the clinical prognosis of the disease in many cases. Future studies should focus on disease eradication through the implementation of control programs against all the interrelated steps in the life cycle of T solium, including human carriers of the adult tapeworm, infected pigs, and eggs in the environment.

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.

Clinical management of neurocysticercosis

Neurocysticercosis is the most common helminthic disease of the nervous system and a leading cause of acquired epilepsy worldwide. Differences in the number and location of lesions as well as in the severity of the immune response against the parasites, makes neurocysticercosis a complex disease. Therefore, a single therapeutic approach is not expected to be useful in every patient. Introduction of cysticidal drugs - praziquantel and albendazole - have changed the prognosis of thousands of patients with neurocysticercosis. While pioneer trials of therapy were flawed by a poor design, recent studies have shown that cysticidal drugs results in disappearance of lesions and clinical improvement in most cases. Nevertheless, some patients with parenchymal neurocysticercosis may be left with remaining cysts and may develop recurrent seizures after therapy, and many patients with subarachnoid cysts may need repeated courses of therapy. In addition, not all forms of the disease benefit from cysticidal drugs.

Neurocysticercosis

Known as a disease of swine in ancient civilizations, cysticercosis is currently considered the most common helminthic infection of the nervous system, and a leading cause of acquired epilepsy worldwide. The disease occurs when humans become intermediate hosts of the tapeworm Taenia solium by ingesting its eggs from contaminated food or, most often, directly from a Taenia carrier by the fecal-oral route. Once in the human intestine, Taenia eggs evolve to oncospheres that, in turn, cross the intestinal wall and lodge in human tissues - especially the nervous system - where cysticerci develop. The brain is a hostile environment in which parasites attempt to escape the immune surveillance while the host is trying to drive out the infection. In some cases, cysticerci are destroyed by this immunological attack, while in others, parasites may live unchanged for years. Cysticerci may be located in brain parenchyma, subarachnoid space, ventricular system, or spinal cord, causing a myriad of pathologic changes that are the main changes responsible for the clinical pleomorphism of neurocysticercosis. Seizures are the most common clinical manifestation of the disease, but some patients present with focal deficits, intracranial hypertension, or cognitive decline. With the exception of cystic lesions showing the scolex as an eccentric nodule, neuroimaging findings of neurocysticercosis are nonspecific and may be seen in other diseases of the nervous system. Likewise, immune diagnostic tests have been faced with problems related to poor sensitivity or specificity. Accurate diagnosis is possible after interpretation of clinical data together with findings of neuroimaging studies and results of immunologic tests, in a proper epidemiologic scenario. The introduction of cysticidal drugs has changed the prognosis of neurocysticercosis. Praziquantel and albendazole have been shown to reduce the burden of infection in the brain (as seen on neuroimaging studies) and to improve the clinical course of the disease in most patients. Further efforts should be directed towards eradicating this disease through the implementation of control programs for all the interrelated steps in the life cycle of T. solium, including human carriers of the adult tapeworm, infected pigs, and eggs in the environment.

Praziquantel treatment in trematode and cestode infections: an update

Status and emerging issues in the use of praziquantel for treatment of human trematode and cestode infections are briefly reviewed. Since praziquantel was first introduced as a broadspectrum anthelmintic in 1975, innumerable articles describing its successful use in the treatment of the majority of human-infecting trematodes and cestodes have been published. The target trematode and cestode diseases include schistosomiasis, clonorchiasis and opisthorchiasis, paragonimiasis, heterophyidiasis, echinostomiasis, fasciolopsiasis, neodiplostomiasis, gymnophalloidiasis, taeniases, diphyllobothriasis, hymenolepiasis, and cysticercosis. However, Fasciola hepatica and Fasciola gigantica infections are refractory to praziquantel, for which triclabendazole, an alternative drug, is necessary. In addition, larval cestode infections, particularly hydatid disease and sparganosis, are not successfully treated by praziquantel. The precise mechanism of action of praziquantel is still poorly understood. There are also emerging problems with praziquantel treatment, which include the appearance of drug resistance in the treatment of Schistosoma mansoni and possibly Schistosoma japonicum, along with allergic or hypersensitivity reactions against praziquantel treatment. To cope with and overcome these problems, combined use of drugs, i.e., praziquantel and other newly introduced compounds such as triclabendazole, artemisinins, and tribendimidine, is being tried.

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.

Neurocysticercosis: a review

Neuroysticercosis is the most common helminthic infection of the nervous system, and a leading cause of acquired epilepsy worldwide. The disease occurs when humans become intermediate hosts of Taenia solium by ingesting its eggs from contaminated food or, most often, directly from a taenia carrier by the fecal-to-oral route. Cysticerci may be located in brain parenchyma, subarachnoid space, ventricular system, or spinal cord, causing pathological changes that are responsible for the pleomorphism of neurocysticercosis. Seizures are the most common clinical manifestation, but many patients present with focal deficits, intracranial hypertension, or cognitive decline. Accurate diagnosis of neurocysticercosis is possible after interpretation of clinical data together with findings of neuroimaging studies and results of immunological tests. The introduction of cysticidal drugs have changed the prognosis of most patients with neurocysticercosis. These drugs have shown to reduce the burden of infection in the brain and to improve the clinical course of the disease in most patients. Further efforts should be directed to eradicate the disease through the implementation of control programs against all the interrelated steps in the life cycle of T. solium, including human carriers of the adult tapeworm, infected pigs, and eggs in the environment.

Disseminated cysticercosis

Disseminated cysticercosis is a rare form of cysticercosis in which the cysticerci spread out through the whole body. We report the first case of a 39-year-old Mongolian with disseminated cysticercosis. He visited our hospital with generalized tonic-clonic seizure. After extensive investigation from brain computed tomography (CT), spine magnetic resonance imaging (MRI), whole body MRI and pathologic biopsy, he was diagnosed as having cysticercosis involving the brain, subcutaneous tissue, and skeletal muscles through the whole body. We treated him with the albendazole in which case the followed MRI showed that numbers of cystic lesions were copiously decreased. We report an unsual case of disseminated cysticercosis treated with medical therapy.

Neurocysticercosis

Neurocysticercosis (NCC) is the most common cause of acquired epilepsy in developing countries. It can present variably depending on the location and stage of cysts in the nervous system, and the host immune response. The most common presentation of parenchymal NCC is with seizures that are usually focal and brief; status epilepticus occurs in some cases. About a third of cases have headache and vomiting. Diagnosis is made by either CT or MRI. Single, small, contrast enhancing lesions are the most common; visualization of a scolex is diagnostic. Some cases have multiple cysts with a characteristic starry-sky appearance. Although treatment with cysticidal therapy continues to be debated, there is increasing evidence that it helps through increased and faster resolution of CT lesions; whether there is any improvement in long-term seizure control needs further study. It should not be used in cysticercus encephalitis or in ophthalmic NCC and used with caution in extraparenchymal NCC. It is of no use in calcified lesions. Corticosteroids are used simultaneously to reduce cerebral oedema. Seizures respond well to a single antiepileptic, and the seizure recurrence rate is low in cases with single lesions; those with multiple, persistent or calcified lesions usually have recurrent seizures. Extraparenchymal NCC is often associated with intracranial hypertension, hydrocephalous and chronic meningitis; it has a guarded prognosis; surgical intervention is required in many cases. Management of NCC needs to be individualized. NCC is potentially eradicable; proper sanitation, hygiene and animal husbandry are warranted.

Acute obstructive hydrocephalus due to cysticercosis during pregnancy

BACKGROUND

Cysticercosis, due to the parasite Taenia solium, can involve any organ. When central nervous system infection occurs, signs and symptoms depend on the location of the cerebral lesions. Most patients develop seizures, focal symptoms, or headaches with nausea and vomiting.

CASE

A case of extraparenchymal (intraventricular) cysticercosis was diagnosed in a patient at term who presented with acute alteration in mental status. Ventriculostomy was performed because of acute obstructive hydrocephalus. Labor ensued and was augmented with oxytocin. Intrapartum management included magnesium sulfate seizure prophylaxis and corticosteroids. Intracranial pressures ranged between 4 and 12 cm H2O peripartum with approximately 300 mL of cerebrospinal fluid drained over the first 24 hours. Postpartum management included craniotomy with resection of a larval cyst and oral praziquantel therapy.

CONCLUSION

This case describes an uncommon presentation of neurocysticercosis that should be considered in gravidas with acute mental status changes.

Antiparasitic drugs in neurocysticercosis: albendazole or praziquantel?

This article evaluates the findings and conclusions of a recent meta-analysis of published data comparing the efficacy of the treatment of neurocysticercosis with albendazole and praziquantel in terms of both resolution of brain cysts and seizure control. From 103 related articles indexed in PubMed and the Cochrane Database of Controlled Trials, and quoted in reference lists, six prospective trials comparing albendazole with praziquantel (including patients infected with parasites in their cystic stage without perilesional inflammation and examining partial or total disappearance of cysts and/or control of seizures) were evaluated. The small number and heterogeneity of the included studies makes it difficult to assess the analyses provided. One of the studies was a pilot trial, at least three had grossly inadequate sample sizes and, owing to the way in which the data are presented in one of the studies, it is not possible to extract the proportion of parasites that resolved. None of the studies was designed to evaluate seizure control. The current published data does not provide enough basis to determine conclusively the superiority of either albendazole or praziquantel as first-line treatment of neurocysticercosis, and the choice of an antiparasitic drug is still guided by collateral factors, including drug availability and costs.

Disseminated cysticercosis: a case report and review of the literature

Introduction

Cysticercosis is a common tropical disease. One of the uncommon manifestations of cysticercosis is its disseminated form.

Case presentation

We report an immunocompetent patient with disseminated cysticercosis, who had involvement of the brain, subcutaneous tissues, skeletal muscles, right orbit and thyroid gland. In addition, this patient developed a serum sickness which responded to therapy.

Conclusion

Wide spread dissemination is a rare complication of cysticercosis. A planned approach to therapy is required.

Albendazole versus praziquantel in the treatment of neurocysticercosis: a meta-analysis of comparative trials

Background

Neurocysticercosis, infection of the brain with larvae of Taenia solium (pork tapeworm), is one of several forms of human cysticercosis caused by this organism. We investigated the role of albendazole and praziquantel in the treatment of patients with parenchymal neurocysticercosis by performing a meta-analysis of comparative trials of their effectiveness and safety.

Methods and Principal Findings

We performed a search in the PubMed database, Cochrane Database of Controlled Trials, and in references of relevant articles. Six studies were included in the meta-analysis. Albendazole was associated with better control of seizures than praziquantel in the pooled data analysis, when the generic inverse variance method was used to combine the incidence of seizure control in the included trials (patients without seizures/[patients×years at risk]) (156 patients in 4 studies, point effect estimate [incidence rate ratio] = 4.94, 95% confidence interval 2.45–9.98). In addition, albendazole was associated with better effectiveness than praziquantel in the total disappearance of cysts (335 patients in 6 studies, random effects model, OR = 2.30, 95% CI 1.06–5.00). There was no difference between albendazole and praziquantel in reduction of cysts, proportion of patients with adverse events, and development of intracranial hypertension due to the administered therapy.

Conclusions

A critical review of the available data from comparative trials suggests that albendazole is more effective than praziquantel regarding clinically important outcomes in patients with neurocysticercosis. Nevertheless, given the relative scarcity of trials, more comparative interventional studies—especially randomized controlled trials—are required to draw a safe conclusion about the best regimen for the treatment of patients with parenchymal neurocysticercosis.

Neurocysticercosis is a parasitic disease caused by the pork tapeworm, Taenia solium, when the larval form of the parasite lodges in the central nervous system. This disease is most commonly found among members of agricultural societies with poor sanitary conditions and economies based on breeding livestock (especially pigs) with low hygiene standards. It is a disease with long history in humans, and the usual therapeutic intervention was surgery until the development of antiparasitic cysticidal agents, the most common being praziquantel and albendazole. T. solium infection can take many different forms in humans, but we concentrated on parenchymal neurocysticercosis with viable cysts. A consensus statement by a panel of experts on the subject supports the use of antiparasitic treatment, but does not indicate either albendazole or praziquantel as the drug of choice for this type of neurocysticercosis, because data from single relevant clinical trials are not conclusive. We conducted a meta-analysis to further evaluate the comparative effectiveness and safety of albendazole and praziquantel for this particular type of neurocysticercosis. The outcomes of our meta-analysis suggest that albendazole is more effective than praziquantel in controlling seizures in affected patients and in leading to the total disappearance of cysts and subsequently cure of patients with neurocysticercosis.

Neuronavigation guided surgery for parenchymal neurocysticercosis in two patients

Neurocysticercosis is a rare disease in the Baltic area while it is common in the endemic regions. Two patients with serologically negative parenchymal neurocysticercosis from our neurosurgical department who underwent extirpation of the cystic lesions with neuronavigation guided surgery are reported in this paper. Though most publications propose medical treatment with albendazole and praziquantel for parenchymal neurocysticercosis, surgery can be an option for diagnosis and treatment in conjunction with cysticidal medication if the diagnosis is unclear particularly in non-endemic areas.

Control of Taenia solium cysticercosis/taeniosis

Cysticercosis is emerging as a serious public health and agricultural problem in many poorer countries of Latin America, Africa, and Asia. Caused by the pork tapeworm, Taenia solium, this zoonotic disease forms larval cysts in humans and pigs that can lead to epilepsy and death in humans, reduces the market value of pigs and makes pork unsafe to eat. It occurs where pigs range freely, sanitation is poor, and meat inspection is absent or inadequate, and is thus strongly associated with poverty and smallholder farming. Although theoretically easy to control and declared eradicable cysticercosis remains neglected in most endemic countries due to lack of information and awareness about the extent of the problem, suitable diagnostic and management capacity, and appropriate prevention and control strategies. Human neurocysticercosis occurs when the larval cysts develop in the brain. It is considered to be the most common parasitic infection of the human nervous system and the most frequent preventable cause of epilepsy in the developing world. Thus far the infection has not been eliminated from any region by a specific program, and no national control programs are yet in place. We consider the tools available for combating cysticercosis and suggest simple packages of interventions, which can be conducted utilizing existing services and structures in the endemic countries to provide appropriate and sustainable control of the disease.

Cysteine proteinase inhibitors in murine cysticercosis

We explored the prophylactic efficacies of two novel protease inhibitors in murine cysticercosis. Our results demonstrated a 95% and 80% reduction in parasite burden for mice injected with Z-LLL-FMK and Z-LLY-FMK, respectively. Further studies are merited on the role of cysteine proteinase inhibitors in treatment of cysticercosis.

Neurocysticercosis

Neurocysticercosis is a leading cause of seizures and epilepsy in the developing world and is an increasingly important health issue in the United States. Recent results from the Cysticercosis Working Group in Peru provide new evidence supporting the use of antiparasitic agents in highly selected patients with active cysts and seizures.

Neurocysticercosis in Mexico

Cysticercosis is caused by the establishment of Taenia solium larvae (cysticerci), mainly in the central nervous system (CNS) and skeletal muscle of humans and pigs, after ingestion of eggs shed in human faeces by the adult tapeworm (see centrepage diagram). Human neurocysticercosis - often a life-threatening disease - is increasingly recognized as a public health problem, especially in developing countries. Clinical incidence of neurocysticercosis can reach 7% in Mexico and 18% in the Ekari population of New Guinea, while prevalence in autopsies ranges from 0.4% to 3.6% in several countries of Latin America, Asia and Africa. Many cases have also been recently reported in the USA, usually in immigrants. In this review, Ana Flisser focuses on the problems of cysticercosis in Mexico, where the disease is now recognized as a priority both in public health and economic terms. Recognition of the problem has been greatly aided in recent years by new developments in diagnosis - especially computed tomography (CT) to diagnose early stages of neurocysticercosis - and by improved drug treatment.

Neurocysticercosis: a review

BACKGROUND

In North America, the largest number of neurosurgical cases stemming from parasitic infections involves the larval form of Taenia solium, the infectious organism causing neurocysticercosis. This infection of the central nervous system (CNS) is most commonly seen in areas with significant immigrant populations and can often present particular challenges to treating physicians.

METHODS

A review of the literature was performed, highlighting the epidemiology, parasitology, and clinical manifestations of neurocysticercosis. Particular attention was paid to 4 locations of neurocysticercosis lesions: parenchymal, subarachnoid/cisternal, intraventricular, and spinal.

RESULTS

Both medical and surgical interventions may be necessary for adequate treatment of neurocysticercosis, depending on various factors, including location of lesion.

CONCLUSIONS

A review of neurocysticercosis, with particular attention paid to location of disease involvement in the CNS, provides important information to the clinical management of this disease.

Neurocysticercosis in children

Neurocysticercosis is a major cause of neurologic disease worldwide. The clinical presentations are pleomorphic depending on the stage and location of cysts in the nervous system. Most children (> 80%) present with seizures, particularly partial seizures; headache and vomiting are seen in about a third of cases. Diagnosis is made by either computed tomography (CT) or magnetic resonance imaging. Single enhancing lesions are the most common finding. Visualization of a scolex confirms the diagnosis. Some cases have multiple cysts; the "starry-sky" appearance in cases with innumerable cysts is characteristic. Most children require anticonvulsants. Corticosteroids are indicated in those with cerebral edema. The efficacy of cysticidal therapy continues to be debated. Controlled studies suggest that cysticidal therapy helps in increased and faster resolution of CT lesions, but there is no conclusive evidence that it improves long-term seizure control. The prognosis in cases with single lesions is good; seizure control is achieved with a single anticonvulsant, and the recurrence rate is low. Children with multiple lesions have recurrent seizures. Extraparenchymal neurocysticercosis is rare in children and carries a poor prognosis. Neurocysticercosis must be considered in the differential diagnosis of seizures and a wide variety of neurologic disorders, particularly in endemic areas.

Fusobacterial brain abscess: a review of five cases and an analysis of possible pathogenesis

OBJECT

The cases of five patients with fusobacterial brain abscess are presented. The authors discuss their attempt to determine the pathogenesis.

METHODS

The clinical and microbiological features of five cases of fusobacterial brain abscess are reviewed. Isolates of 2031 Fusobacterium spp. and other anaerobes collected (1989-2002) at our institution were analyzed and compared for incidences and isolation sources. The findings were correlated with extensive literature on the subject. The five patients were men between 45 and 74 years of age. All experienced an insidious onset of the disease and probable hematogenous seeding of the organism(s). One patient had a monomicrobic Fusobacterium necrophorum abscess, whereas the others had polymicrobic F. nucleatum abscesses. Despite surgery and a regimen of antibiotic medications and dexamethasone, three patients experienced a paradoxical deterioration 3 days postoperatively that necessitated reevacuation of the lesion. The evacuants observed at that time contained numerous leukocytes but no microorganisms, suggesting intensified inflammation as the likely cause of deterioration. This explanation is supported by literature that fusobacteria strongly activate neutrophils. An analysis of the 2031 anaerobes from blood, wounds, and abscesses showed the considerable virulence of Fusobacterium spp., which were able to enter and/or sustain themselves in the blood circulation. This pattern was similar to that of Clostridium spp., but different from those of Peptostreptococcus spp., Bacteroides spp., and Prevotella spp., which were less invasive but more abundant.

CONCLUSIONS

Some fusobacterial brain abscesses may be associated with a paradoxical postoperative deterioration, which is probably due to intensified inflammation following treatment. The blood-borne dissemination and invasive behavior of fusobacteria likely initiate such a brain abscess, and further seeding of other synergic bacteria leads to a polymicrobic abscess.

Taenia solium cysticercosis

The larval stage of the pork tapeworm (Taenia solium) infects the human nervous system, causing neurocysticercosis. This disease is one of the main causes of epileptic seizures in many less developed countries and is also increasingly seen in more developed countries because of immigration from endemic areas. Little information is available on the natural evolution of taeniasis or cysticercosis. Available therapeutic measures include steroids, treatments for symptoms, surgery, and, more controversially, antiparasitic drugs to kill brain parasites. Efforts to control and eliminate this disease are underway through antiparasitic treatment of endemic populations, development of pig vaccines, and other measures.

Human case management and treatment of cysticercosis

Disease manifestations due to neurocysticercosis vary markedly and depend upon the location, size and number of cysts as well as the viability or degeneration of cysts and presence, type and degree of host response. Accordingly, the clinical management for each patient should be individualized. Treatment modalities include: (1) larvicidal drugs such as albendazole or praziquantel in patients with viable cysts; (2) corticosteroids or other agents to suppress or prevent the host's immune response; (3) anti-seizure medication(s) to treat or prevent recurrent seizures; (4) surgical interventions; and (5) the use of supportive family, social or health agencies in impaired individuals. Although it is known that larvicidal treatment kills viable cysts that commonly resolve or calcify, the clinical benefit of this treatment in the most common presentations is unproven. However, medical treatment of giant subarachnoid cysts, large parenchymal cysts or orbital cysts causing mass effect has led to definite clinical improvement in uncontrolled trials. Whether there is faster radiological improvement and/or clinical benefit in the treatment of cysts showing signs of inflammation by magnetic resonance imaging (enhancement and/or edema) is like-wise controversial. There is no general understanding when or how to use corticosteroids to suppress natural or treatment-induced inflammation around cysts although their use when inflammation contributes or could be expected to cause undue morbidity or mortality is reasonable. Anti-seizure medication should usually be employed in patients with seizures or patients who may likely develop seizures. Surgical intervention is required to alleviate mass effect, remove some cysts causing obstruction of the ventricles, shunt placement for hydrocephalus, and sometimes for removal and/or decompression of large or critically located cysts before larvicidal treatment.