Late-onset eosinophilic chronic meningitis occurring 30 years after Taenia solium infestation in a white Caucasian woman

The leptomeninges as a critical organ for normal CNS development and function: First patient and public involved systematic review of arachnoiditis (chronic meningitis)

BACKGROUND & IMPORTANCE

This patient and public-involved systematic review originally focused on arachnoiditis, a supposedly rare "iatrogenic chronic meningitis" causing permanent neurologic damage and intractable pain. We sought to prove disease existence, causation, symptoms, and inform future directions. After 63 terms for the same pathology were found, the study was renamed Diseases of the Leptomeninges (DLMs). We present results that nullify traditional clinical thinking about DLMs, answer study questions, and create a unified path forward.

METHODS

The prospective PRISMA protocol is published at Arcsology.org. We used four platforms, 10 sources, extraction software, and critical review with ≥2 researchers at each phase. All human sources to 12/6/2020 were eligible for qualitative synthesis utilizing R. Weekly updates since cutoff strengthen conclusions.

RESULTS

Included were 887/14286 sources containing 12721 DLMs patients. Pathology involves the subarachnoid space (SAS) and pia. DLMs occurred in all countries as a contributor to the top 10 causes of disability-adjusted life years lost, with communicable diseases (CDs) predominating. In the USA, the ratio of CDs to iatrogenic causes is 2.4:1, contradicting arachnoiditis literature. Spinal fusion surgery comprised 54.7% of the iatrogenic category, with rhBMP-2 resulting in 2.4x more DLMs than no use (p<0.0001). Spinal injections and neuraxial anesthesia procedures cause 1.1%, and 0.2% permanent DLMs, respectively. Syringomyelia, hydrocephalus, and arachnoid cysts are complications caused by blocked CSF flow. CNS neuron death occurs due to insufficient arterial supply from compromised vasculature and nerves traversing the SAS. Contrast MRI is currently the diagnostic test of choice. Lack of radiologist recognition is problematic.

DISCUSSION & CONCLUSION

DLMs are common. The LM clinically functions as an organ with critical CNS-sustaining roles involving the SAS-pia structure, enclosed cells, lymphatics, and biologic pathways. Cases involve all specialties. Causes are numerous, symptoms predictable, and outcomes dependent on time to treatment and extent of residual SAS damage. An international disease classification and possible treatment trials are proposed.

Reduced Leukocyte Infiltration in Absence of Eosinophils Correlates with Decreased Tissue Damage and Disease Susceptibility in ΔdblGATA Mice during Murine Neurocysticercosis

Neurocysticercosis (NCC) is one of the most common helminth parasitic diseases of the central nervous system (CNS) and the leading cause of acquired epilepsy worldwide. NCC is caused by the presence of the metacestode larvae of the tapeworm Taenia solium within brain tissues. NCC patients exhibit a long asymptomatic phase followed by a phase of symptoms including increased intra-cranial pressure and seizures. While the asymptomatic phase is attributed to the immunosuppressive capabilities of viable T. solium parasites, release of antigens by dying organisms induce strong immune responses and associated symptoms. Previous studies in T. solium-infected pigs have shown that the inflammatory response consists of various leukocyte populations including eosinophils, macrophages, and T cells among others. Because the role of eosinophils within the brain has not been investigated during NCC, we examined parasite burden, disease susceptibility and the composition of the inflammatory reaction in the brains of infected wild type (WT) and eosinophil-deficient mice (ΔdblGATA) using a murine model of NCC in which mice were infected intracranially with Mesocestoides corti, a cestode parasite related to T. solium. In WT mice, we observed a time-dependent induction of eosinophil recruitment in infected mice, contrasting with an overall reduced leukocyte infiltration in ΔdblGATA brains. Although, ΔdblGATA mice exhibited an increased parasite burden, reduced tissue damage and less disease susceptibility was observed when compared to infected WT mice. Cellular infiltrates in infected ΔdblGATA mice were comprised of more mast cells, and αβ T cells, which correlated with an abundant CD8⁺ T cell response and reduced CD4⁺ Th1 and Th2 responses. Thus, our data suggest that enhanced inflammatory response in WT mice appears detrimental and associates with increased disease susceptibility, despite the reduced parasite burden in the CNS. Overall reduced leukocyte infiltration due to absence of eosinophils correlates with attenuated tissue damage and longer survival of ΔdblGATA mice. Therefore, our study suggests that approaches to clear NCC will require strategies to tightly control the host immune response while eradicating the parasite with minimal damage to brain tissue.

Eosinophils are known to mediate a protective response against several parasitic infections. This is largely accomplished by eosinophil degranulation (direct killing) and modulating effective adaptive immune responses. Consequently, eosinophils can also contribute to host pathology via a bystander effect. However, the outcome of infection varies depending upon the parasite species. In the case of neurocysticercosis (NCC), the role of eosinophils in disease progression has not been investigated despite the known eosinophilic response in patients. NCC is one of the most common parasitic diseases of the brain which is caused by the metacestode (larva) of the tapeworm Taenia solium. To determine the role of eosinophils in NCC disease outcome, we used a murine model of NCC in which wildtype (WT) or eosinophil deficient mice (ΔdblGATA) were infected intracranially with Mesocestoides corti, a cestode parasite related to T. solium. Our data show that murine NCC is characterized by a robust eosinophil response that correlates with lower parasite burden in the brain. Comparison of T cell response reveals a mixed Th1/Th2 in the WT brain, and ΔdblGATA mice showed a significant decrease in both population but in particular in the Th2 response. In addition, the strong eosinophil reaction observed in WT brains correlates with exacerbated pathology and increased morbidity. Thus, our study suggest that eosinophils act as a double-edged sword playing a role in controlling the infection but worsening the disease outcome by contributing to host pathology.

Eosinophilia in Infectious Diseases

In determining the etiology of eosinophilia, it is necessary to consider the type of patient, including previous travel and exposure history, comorbidities, and symptoms. In this review, we discuss the approach to the patient with eosinophilia from an infectious diseases perspective based on symptom complexes.

Neurocysticercosis in Europe: Still a public health concern not only for imported cases

Neurocysticercosis (NCC), a parasitic disease caused by the larvae of the cestode Taenia solium, is the most frequent parasitic disease of the central nervous system (CNS) in the world and the leading cause of secondary epilepsy in Central and South America, East and South Asia, and sub-Saharan Africa. It is endemic in many low- and middle-income countries of the world. Due to increased travels and immigration, NCC may be diagnosed also in non-endemic areas. In fact, tapeworm carriers from endemic zones can transmit infection to other citizens or arrive already suffering NCC. This phenomenon, occurred first in USA during the last 30 years, has been also observed in Europe, as well as in Australia, Canada, Israel, Japan and Muslim countries of the Arab World. Actually, concerning Europe, although, in some areas only few cases have been described, nevertheless the prevalence of NCC may be considered increasing, especially in Spain and Portugal. We reviewed the literature on the burden of NCC in Europe, by a search of PubMed regarding papers from 1970 to present. We only considered on PubMed published and available papers in English, French, Italian, and Spanish, the languages understood by the authors. One hundred seventy six cases of NCC have been reported in seventeen European countries (Austria, Belgium, Denmark, Finland, France, Germany, Greece, Hungary, Ireland, Italy, Latvia, Netherlands, Sweden, United Kingdom, and Croatia, Norway, Switzerland). A particular epidemic situation is present in Spain and Portugal. In fact, we collected data that show, in Spain, an increasing incidence both in immigrated patients and in those which were born in certain Spanish geographical areas and, in Portugal, prevalence similar to that observed in endemic areas. Globally, it is clear that as a result of increased migrations and travels from endemic regions, NCC is becoming an emerging public health problem in high-income countries, particularly affecting communities where hygiene conditions are poor and sub-sequentially the parasite can spread from human to human through eggs even in absence of a travel to the tropics. NCC is a preventable disease, it derives that it's important to acquire a great consciousness of the epidemiology and to implement accurate surveillance systems.

Epidemiology and management of cysticercosis and Taenia solium taeniasis in Europe, systematic review 1990-2011

BACKGROUND

Cysticercosis is caused by the invasion of human or pig tissues by the metacestode larval stage of Taenia solium. In Europe, the disease was endemic in the past but the autochthonous natural life cycle of the parasite is currently completed very rarely. Recently, imported cases have increased in parallel to the increased number of migrations and international travels. The lack of specific surveillance systems for cysticercosis leads to underestimation of the epidemiological and clinical impacts.

OBJECTIVES

To review the available data on epidemiology and management of cysticercosis in Europe.

METHODS

A review of literature on human cysticercosis and T. solium taeniasis in Europe published between 1990-2011 was conducted.

RESULTS

Out of 846 cysticercosis cases described in the literature, 522 cases were autochthonous and 324 cases were imported. The majority (70.1%) of the autochthonous cases were diagnosed in Portugal from 1983 and 1994. Imported cases of which 242 (74.7%) diagnosed in migrants and 57 (17.6%) in European travellers, showed an increasing trend. Most of imported cases were acquired in Latin America (69.8% of migrants and 44.0% of travellers). The majority of imported cases were diagnosed in Spain (47.5%), France (16.7%) and Italy (8.3%). One third of neurosurgical procedures were performed because the suspected diagnosis was cerebral neoplasm. Sixty eight autochthonous and 5 imported T. solium taeniasis cases were reported.

CONCLUSIONS

Cysticercosis remains a challenge for European care providers, since they are often poorly aware of this infection and have little familiarity in managing this disease. Cysticercosis should be included among mandatory reportable diseases, in order to improve the accuracy of epidemiological information. European health care providers might benefit from a transfer of knowledge from colleagues working in endemic areas and the development of shared diagnostic and therapeutic processes would have impact on the quality of the European health systems.

Neurocysticercosis in Western Europe: a re-emerging disease?

The objective of the study was to estimate the magnitude of neurocysticercosis in Western Europe and to determine the pattern of disease expression in the region. Review of patients with neurocysticercosis diagnosed in Western Europe from 1970 to 2011. Abstracted data included: demographic profile, clinical manifestations, form of neurocysticercosis, and whether the disease occurred in immigrants, European international travelers, or Europeans who had never been abroad. A total of 779 patients were found. Of these, only 28 were diagnosed before 1985. Countries with more reported patients were Portugal (n = 384), Spain (n = 228), France (n = 80), The United Kingdom (n = 26), and Italy (n = 21). Information on citizenship status, clinical manifestations, and forms of the disease was available in only 30-40% of patients. Immigrants accounted for 53% of cases, European travelers for 8%, and non-traveler Europeans for 39%. Immigrants/European travelers were most often diagnosed during the new Millennium, presented most often with seizures, and had less frequently inactive (calcified) neurocysticercosis than non-traveler Europeans. The prevalence of neurocysticercosis in Western Europe may be on the rise. The pattern of disease expression is different among immigrants/European travelers than among non-traveler Europeans. It is possible that some patients had acquired the disease as the result of contact with Taenia solium carriers coming from endemic countries. Much remains to be learned on the prevalence of neurocysticercosis in this region.

Neurocysticercosis among international travelers to disease-endemic areas

OBJECTIVE

Review of neurocysticercosis in citizens from non-endemic countries who developed the disease after a travel to endemic regions, to estimate the magnitude of the disease and to determine the pattern of disease expression in travelers to disease-endemic areas.

METHODS

MEDLINE and manual search of international travelers with neurocysticercosis diagnosed in countries where the disease is not endemic, from 1981 to October 2011. Abstracted data included: demographic profile of patients, clinical manifestations, form of neurocysticercosis, and therapy.

RESULTS

A total of 35 articles reporting 52 patients were found. Most patients were originally from Western Europe, Australia, Israel, and Japan. Mean age was 36.5 ± 15.1 years, and 46% were women. Common places for travelling were the Indian Subcontinent, Latin America, and Southeast Asia. Mean time spent aboard was 56.6 ± 56.1 months. Most patients developed symptoms 2 years or more after returning home. Seizures were the most common clinical manifestation of the disease (73%), and all but six patients had parenchymal brain cysticercosis (a single cysticercus granuloma was the most common neuroimaging finding, in 21 patients). Twenty patients underwent surgical resection of the brain lesion for diagnostic purposes, and 22 received cysticidal drugs.

CONCLUSIONS

Neurocysticercosis is rare in international travelers to endemic countries, and most often occurs in long-term travelers. It is possible that most of these patients get infected by contact with a taenia carrier. The time elapsed between disease acquisition and symptoms occurrence suggests that, at least in some patients, clinical manifestations are related to reactivation of an infection that has previously been controlled by the host immune system.

Severe cysticercal meningitis: clinical and imaging characteristics

In disease-endemic areas, severe cysticercal meningitis (SCM) is characterized by intense inflammatory cerebrospinal fluid (CSF) and negative bacterial and fungal cultures. There have been no systematic studies of SCM. We characterized patients with SCM and compare them with neurocysticercosis (NC) patients with mild CSF abnormalities by conducting a nine-year retrospective review at a neurological referral center. Two groups of patients were compared: group A, those with severe CSF pleocytosis > 1,000 cells/mm(3) (n = 12), and group B, those with CSF pleocytosis <or= 1,000 cells/mm(3) (n = 126). All patients had positive CSF results in an enzyme-linked immunosorbent assay for cysticercal antigens and negative CSF cultures for bacteria, fungi, and mycobacteria. Intracranial hypertension, meningeal signs, CSF hypoglycorrachia, and a longer clinical course of NC were more frequently seen in group A. It is likely that SCM often goes unrecognized. Its correct identification may reduce morbidity and risks of unnecessary surgery in patients with chronic NC and CSF shunts.