Diagnosis of atypical neurocysticercosis by polymerase chain reaction analysis: case report

Next-Generation Sequencing of Cerebrospinal Fluid for the Diagnosis of Neurocysticercosis

Background: Neurocysticercosis (NCC) is the most common helminthic infection of the central nervous system (CNS). The diagnosis of NCC is sometimes challenging due to its heterogenous clinical manifestations and the variable sensitivity and specificity of neuroimaging and serological tests. Methods: Next-generation sequencing (NGS) of cerebrospinal fluid (CSF) was used to detect pathogens in patients with clinically suspected CNS infections. A series of patients diagnosed with NCC is reviewed here. Results: Using NGS of CSF, four patients were diagnosed with NCC. The reads corresponding to Taenia solium ranged from 478 to 117,362, with genomic coverage of 0.0564-11.15%. Reads corresponding to T. solium were not found in non-template controls and far exceeded those of the background microorganisms in patients with NCC, facilitating the interpretation of the NGS results. Conclusions: This case series demonstrates that NGS of CSF is promising in the diagnosis of NCC in difficult to diagnose cases. Larger studies are needed in the future.

Validity of a PCR assay in CSF for the diagnosis of neurocysticercosis

Objective:

To prospectively evaluate the validity of a PCR assay in CSF for the diagnosis of neurocysticercosis (NC).

Methods:

We conducted a multicenter, prospective case-control study, recruiting participants from 5 hospitals in Cuenca, Ecuador, from January 2015 to February 2016. Cases fulfilled validated diagnostic criteria for NC. For each case, a neurosurgical patient who did not fulfill the diagnostic criteria for NC was selected as a control. CT and MRI, as well as a CSF sample, were collected from both cases and controls. The diagnostic criteria to identify cases were used as a reference standard.

Results:

Overall, 36 case and 36 control participants were enrolled. PCR had a sensitivity of 72.2% (95% confidence interval [CI] 54.8%–85.8%) and a specificity of 100.0% (95% CI 90.3%–100.0%). For parenchymal NC, PCR had a sensitivity of 42.9% (95% CI 17.7%–71.1%), and for extraparenchymal NC, PCR had a sensitivity of 90.9% (95% CI 70.8%–98.9%).

Conclusions:

This study demonstrated the usefulness of this PCR assay in CSF for the diagnosis of NC. PCR may be particularly helpful for diagnosing extraparenchymal NC when neuroimaging techniques have failed.

Classification of evidence:

This study provides Class III evidence that CSF PCR can accurately identify patients with extraparenchymal NC.

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.

Cysticerci-related single parenchymal brain enhancing lesions in non-endemic countries

OBJECTIVE

Review of case reports and case series of patients with single cysticercus granulomas in non-endemic countries to determine the characteristics of this form of neurocysticercosis in these regions.

METHODS

MEDLINE and manual search of patients with single cysticercus granulomas diagnosed in non-endemic countries from 1991 to 2011. Abstracted data included: demographic profile, clinical manifestations, form of neurocysticercosis, and whether the disease occurred in immigrants, international travelers, or citizens from non-endemic countries who had never been abroad.

RESULTS

A total of 77 patients were found. Of these, 61 (79%) were diagnosed since the year 2000. Thirty-four patients (44%) patients were immigrants from endemic countries, 18 (23%) were international travelers returning from disease-endemic areas, and the remaining 25 (33%) were citizens from non-endemic countries who had never been abroad. Most immigrants and international travelers became symptomatic two or more years after returning home. Countries with the most reported patients were Kuwait (n=18), UK (n=11), Australia (n=8), USA (n=7), Japan (n=6), and Israel (n=5).

CONCLUSIONS

A single cerebral cysticercus granuloma in a non-endemic country is not a rare event. As seen in endemic regions, these cases have a good prognosis although more surgical procedures are performed in non-endemic countries, likely reflecting a decrease of diagnostic suspicion for cysticercosis and an increased availability of surgical options. The mean age of the reported cases was 25 years, and immigrants most often developed the disease greater than two years after arrival into a non-endemic area, suggesting a significant delay between infection and symptoms. However, some may have been infected and developed the disease while residing in non-endemic countries.

Neurocysticercosis in a preschool-age child: case report

Neurocysticercosis is a frequent cause of epilepsy and other neurologic abnormalities in all age groups, however by virtue of its prolonged incubation period as well as young children's nutritional habits, it is rarely seen in preschool-age children. The objective of this study is to report the case of a 2 year-old child who presented with new-onset seizures. Her diagnostic features, including neuroradiologic findings, are described and compared with the literature. No matter how young he or she may be, every child who presents with new-onset seizures or other unexplained neurologic features and whose CT or MRI shows cystic lesions or contrast-enhancing rounded lesions should raise a suspicion of neurocysticercosis.