Onchocerca volvulus is not detected in the cerebrospinal fluid of persons with onchocerciasis-associated epilepsy.

OBJECTIVES: Epidemiological evidence links onchocerciasis with the development of epilepsy. The aim of this study was to detect Onchocerca volvulus microfilariae or its bacterial endosymbiont, Wolbachia, in the cerebrospinal fluid (CSF) of persons with onchocerciasis-associated epilepsy (OAE). METHODS: Thirteen persons with OAE and O. volvulus skin snip densities of >80 microfilariae were recruited in Maridi County (South Sudan) and their CSF obtained. Cytospin centrifuged preparations of CSF were examined by light microscopy for the presence of O. volvulus microfilariae. DNA was extracted from CSF to detect O. volvulus (O-150 repeat) by quantitative real-time PCR, and Wolbachia (FtsZ gene) by standard PCR. To further investigate whether CSF from onchocerciasis-infected participants could induce seizures, 3- and 7-day old zebrafish larvae were injected with the CSF intracardially and intraperitoneally, respectively. For other zebrafish larvae, CSF was added directly to the larval medium. RESULTS: No microfilariae, parasite DNA, or Wolbachia DNA were detected in any of the CSF samples by light microscopy or PCR. All zebrafish survived the procedures and none developed seizures. CONCLUSIONS: The absence of O. volvulus in the CSF suggests that OAE is likely not caused by direct parasite invasion into the central nervous system, but by another phenomenon triggered by O. volvulus infection.

Next generation sequencing based pathogen analysis in a patient with neurocysticercosis: a case report.

BACKGROUND: Accurate and early diagnosis of neurocysticercosis (NCC) remains a challenge due to the heterogeneity of its clinical, immunological and imaging characteristics. The presence of cysticercus DNA in cerebrospinal fluid (CSF) of NCC patients has been previously detected via conventional PCR assays. To the best of our knowledge, the use of CSF Next-Generation Sequencing (NGS) based pathogen analysis in patients with NCC infection has never been reported. CASE PRESENTATION: This study reports the clinical, imaging, and immunological features of a patient initially presenting with several months of headache who further developed a pure sensory stroke. NGS was used to detect the pathogen, and her CSF demonstrated the presence of Taenia solium-DNA. This finding was confirmed by a positive reaction to CSF cysticercosis antibodies. After antiparasitic treatment, secondary CSF NGS revealed the DNA index have dropped considerably compared to the initial NGS readings. CONCLUSIONS: NGS is a promising tool for the early and accurate diagnosis of central nervous system (CNS) infection, especially in the setting of atypical clinical manifestations. Further studies are required to evaluate the persistence of DNA in the CSF of patients.

Angiostrongylus cantonensis DNA in Cerebrospinal Fluid of Persons with Eosinophilic Meningitis, Laos.

Definitive identification of Angiostrongylus cantonensis parasites from clinical specimens is difficult. As a result, regional epidemiology and burden are poorly characterized. To ascertain presence of this parasite in patients in Laos with eosinophilic meningitis, we performed quantitative PCRs on 36 cerebrospinal fluid samples; 4 positive samples confirmed the parasite's presence.

Impedimetric nanostructured genosensor for detection of schistosomiasis in cerebrospinal fluid and serum samples.

Schistosomiasis is a neglected disease closely related to the low levels of social development and a serious public health problem. In this work, we performed an electrochemical detection of Schistosoma mansoni DNA with a self-assembled monolayer of mercaptobenzoic acid (MBA) immobilizing nanostructures composed of gold nanoparticles (AuNPs) and magnetite nanoparticles (Fe3O4_NPs). Electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV) were used to monitor the hybridization process. MBA-Fe3O4_NPs-AuNPs-DNAprobe system reveals an effective electrochemical response indicating the surface modification. The proposed biosystem was capable to recognize specific nucleotide sequence of S. mansoni present in cerebrospinal fluid (CFS) and serum samples at different genome DNA concentrations. The biorecognition resulted in an increase in the electron transfer resistance and a decrease of the current peaks at higher DNA concentrations during electrochemical measurements. The developed platform showed a DNA detection limit of 0.781 and 0.685pgµL-1 for serum and CFS, respectively. Therefore, the obtained biosensor can be considered as a useful tool for specific detection of S. mansoni at low concentrations in various biological fluids.

Real-Time Polymerase Chain Reaction Detection of Angiostrongylus cantonensis DNA in Cerebrospinal Fluid from Patients with Eosinophilic Meningitis.

Angiostrongylus cantonensis is the most common infectious cause of eosinophilic meningitis. Timely diagnosis of these infections is difficult, partly because reliable laboratory diagnostic methods are unavailable. The aim of this study was to evaluate the usefulness of a real-time polymerase chain reaction (PCR) assay for the detection of A. cantonensis DNA in human cerebrospinal fluid (CSF) specimens. A total of 49 CSF specimens from 33 patients with eosinophilic meningitis were included: A. cantonensis DNA was detected in 32 CSF specimens, from 22 patients. Four patients had intermittently positive and negative real-time PCR results on subsequent samples, indicating that the level of A. cantonensis DNA present in CSF may fluctuate during the course of the illness. Immunodiagnosis and/or supplemental PCR testing supported the real-time PCR findings for 30 patients. On the basis of these observations, this real-time PCR assay can be useful to detect A. cantonensis in the CSF from patients with eosinophilic meningitis.

Eosinophilia à deux: a brain nagging souvenir from the Philippines.

Angiostrongylus cantonensis is the most common cause of eosinophilic meningitis. Although a rare condition among travelers, increased travel and global transportation of food products may result in more cases across non-endemic, developed countries in the future. We here describe two men with headache and painful skin after visiting the Philippines as presenting symptoms. Subsequently, confusion and focal neurologic symptoms developed. Both had increased serum eosinophils; however, CSF eosinophilia was only demonstrated after repeated lumbar puncture. In the CSF of both, Angiostrongylus spp. DNA was detected. Both were treated with albendazole combined with corticosteroids, after which symptoms improved.

Diagnosis of neuroschistosomiasis by antibody specificity index and semi-quantitative real-time PCR from cerebrospinal fluid and serum.

We describe the case of a 16-year-old German male expatriate from Ghana who presented with obstipation, dysuria, dysaesthesia of the gluteal region and the lower limbs, bilateral plantar hypaesthesia and paraesthesia without pareses. A serum-cerebrospinal fluid (CSF) Schistosoma spp. specific antibody specificity index of 3.1 was considered highly suggestive of intrathecal synthesis of anti-Schistosoma spp. specific antibodies, although standardization of this procedure has not previously been described. Diagnosis was confirmed by detection of Schistosoma DNA in CSF by semi-quantitative real-time PCR at 100-fold concentration compared with serum. Accordingly the two diagnostic procedures, which have not previously been applied for routine diagnosis, appear to be useful for the diagnosis of neuroschistosomiasis. Clinical symptoms resolved following anthelmintic and anti-inflammatory therapy.

Toxocara encephalitis presenting with autonomous nervous system involvement.

Human toxocariasis has been reported to cause a broad spectrum of neurological syndromes, including encephalitis, meningitis and meningo-radiculitis. Nevertheless, cerebral infection by Toxocara may go undiagnosed due to its rarity, elusive symptoms and lack of availability of appropriate testing. We report the case of a 54-year-old man who presented with abdominal pain and paralytic ileus approximately 3 weeks after having eaten raw snails (a folk remedy for peptic ulcer). Three weeks later, marked eosinophilia ensued, associated with mental clouding, nystagmus, diplopia, peripheral limbs ataxia, urinary retention, slackened deep tendon reflexes, arthralgias and myalgias. Cerebrospinal fluid (CSF) examination demonstrated an eosinophilic meningitis, and Toxocara canis cerebral infection was diagnosed by positive serology and by the detection of T. canis DNA in the CSF. The patient made a full recovery following treatment with albendazole and corticosteroids. Physicians should be aware of this rare presentation of toxocariasis, whose diagnosis is, today, facilitated by molecular biology techniques. A history of ingestion of raw snails may alert the clinician to consider the possibility of such an uncommon condition.

Neurocysticercosis: detection of Taenia solium DNA in human cerebrospinal fluid using a semi-nested PCR based on HDP2.

Human neurocysticercosis (NC) is caused by Taenia solium larvae lodged in the central nervous system. This disease is usually diagnosed by radiology but the results are not always clear-cut and so immunological assays are often also used. A semi-nested PCR, based on the non-coding HDP2 sequence of T. saginata, has now been developed for detecting DNA from T. solium cysticerci and confirming NC. This PCR, which amplifies a 171-bp T. solium product, allowed the specific detection of just 174 attograms of T. solium DNA. The efficacy of the PCR was tested using cerebrospinal fluid (CSF) from neurological patients, including 46 confirmed Mexican cases of NC and 32 patients from non-endemic Spain. Eighteen of the confirmed cases [including 10 (71%) of the 14 with vesicular extraparenchymal cysticerci and four (17%) of the 24 with damaged cysticerci] and two (33%) of the six patients with 'uncertain' diagnosis (in whom a diagnosis of NC could not be established by radiological and immunological studies) were found PCR-positive. The 36 patients known to have neurological problems other than NC were found PCR-negative. The HDP2 PCR offers a new tool in the diagnosis of NC and in exploring the pathogenesis of this serious disease.