Neuropsychological sequelae of bacterial and viral meningitis

Long-term sequelae after viral meningitis and meningoencephalitis are frequent, even in mildly affected patients, a prospective observational study

Introduction

An increasing number of studies demonstrate that viral meningitis and meningoencephalitis, even those with a mild course of meningitis, can result in residual sequelae.

Methods

We aimed to investigate the long-term outcome in both viral meningitis and meningoencephalitis/encephalitis patients and impact of long-term sequelae on patients' social and professional daily lives in a prospective observational study with a follow-up period of 20 months.

Results

A total of 50 patients (12% encephalitis, 58% meningoencephalitis and 30% meningitis) and 21 control persons participated in the study. The most common cause was the tick-borne encephalitis (TBE) virus. The most important persistent signs and symptoms after 2 years were subjective cognitive impairment (36%), fatigue and/or excessive daytime sleepiness (31%), disturbed nighttime sleep (31%) and headaches (13%), as well as feeling more rapidly exhausted after cognitive effort (53%). Independent of disease severity in the acute phase, almost one third of patients still reported mildly impaired social and/or professional life due to the long-term sequelae, with scores in the health status assessment still significantly lower compared to healthy controls.

Discussion

Regardless of the severity of the acute illness and despite constant improvement within 2 years, 67% of patients still had persistent signs and symptoms, but these were only relevant to everyday social or professional life in about 30% of these patients.

Tenascin-C in patients with central nervous system infections

BACKGROUND

The extracellular matrix protein tenascin-C has been discovered to be an important regulator of the response to tissue injury and repair in cerebrovascular diseases. This study investigated if tenascin-C is released in response to infections in the central nervous system (CNS).

METHODS

Tenascin-C concentration in the cerebrospinal fluid (CSF) was measured in patients, (>18 years) with and without CNS infections, admitted to a department of infectious diseases in Denmark. CSF tenascin-C was measured on the Meso-scale platform.

RESULTS

174 patients were included of which 140 were diagnosed with a CNS infection and 34 where this was ruled out (control group). Median CSF tenascin-C levels were significantly higher among patients with bacterial meningitis (147 pg/mL), viral meningitis (33 mg/mL), viral encephalitis (39 pg/mL) and Lyme neuroborreliosis (45 pg/mL) when compared to controls (21 pg/mL). Correlations between tenascin-C and CSF markers of inflammation and age were only moderate.

CONCLUSION

Levels of CSF tenascin-C are higher among patients with bacterial and viral neuroinfections, already on admission, but exhibit only a modest correlation with baseline indices of neuroinflammation. CSF tenascin-C is highest among patients with bacterial meningitis compared to the other CNS infections. Patients with unfavorable outcomes presented with higher median CSF tenascin-C than their counterparts.

The single D380 amino acid substitution increases pneumolysin cytotoxicity toward neuronal cells

Bacterial meningitis, frequently caused by Streptococcus pneumoniae (pneumococcus), represents a substantial global health threat leading to long-term neurological disorders. This study focused on the cholesterol-binding toxin pneumolysin (PLY) released by pneumococci, specifically examining clinical isolates from patients with meningitis and comparing them to the PLY-reference S. pneumoniae strain D39. Clinical isolates exhibit enhanced PLY release, likely due to a significantly higher expression of the autolysin LytA. Notably, the same single amino acid (aa) D380 substitution in the PLY D4 domain present in all clinical isolates significantly enhances cholesterol binding, pore-forming activity, and cytotoxicity toward SH-SY5Y-derived neuronal cells. Scanning electron microscopy of human neuronal cells and patch clamp electrophysiological recordings on mouse brain slices confirm the enhanced neurotoxicity of the PLY variant carrying the single aa substitution. This study highlights how a single aa modification enormously alters PLY cytotoxic potential, emphasizing the importance of PLY as a major cause of the neurological sequelae associated with pneumococcal meningitis.

Application of metabolomics in diagnostics and differentiation of meningitis: A narrative review with a critical approach to the literature

Due to its high mortality rate associated with various life-threatening sequelae, meningitis poses a vital problem in contemporary medicine. Numerous algorithms, many of which were derived with the aid of artificial intelligence, were brought up in a strive for perfection in predicting the status of sepsis-related survival or exacerbation. This review aims to provide key insights on the contextual utilization of metabolomics. The aim of this the metabolomic approach set of methods can be used to investigate both bacterial and host metabolite sets from both the host and its microbes in several types of specimens - even in one's breath, mainly with use of two methods - Mass Spectrometry (MS) and Nuclear Magnetic Resonance (NMR). Metabolomics, and has been used to elucidate the mechanisms underlying disease development and metabolic identification changes in a wide range of metabolite contents, leading to improved methods of diagnosis, treatment, and prognosis of meningitis. Mass spectrometry (MS) and Nuclear Magnetic Resonance (NMR) are the main analytical platforms used in metabolomics. Its high sensitivity accounts for the usefulness of metabolomics in studies into meningitis, its sequelae, and concomitant comorbidities. Metabolomics approaches are a double-edged sword, due to not only their flexibility, but also - high complexity, as even minor changes in the multi-step methods can have a massive impact on the results. Information on the differential diagnosis of meningitis act as a background in presenting the merits and drawbacks of the use of metabolomics in context of meningeal infections.

Clinical features and prognostic factors in adults with viral meningitis

Clinical features applicable to the entire spectrum of viral meningitis are limited, and prognostic factors for adverse outcomes are undetermined. This nationwide population-based prospective cohort study included all adults with presumed and microbiologically confirmed viral meningitis in Denmark from 2015 until 2020. Prognostic factors for an unfavourable outcome (Glasgow Outcome Scale score of 1-4) 30 days after discharge were examined by modified Poisson regression. In total, 1066 episodes of viral meningitis were included, yielding a mean annual incidence of 4.7 episodes per 100 000 persons. Pathogens were enteroviruses in 419/1066 (39%), herpes simplex virus type 2 in 171/1066 (16%), varicella-zoster virus in 162/1066 (15%), miscellaneous viruses in 31/1066 (3%) and remained unidentified in 283/1066 (27%). The median age was 33 years (IQR 27-44), and 576/1066 (54%) were females. In herpes simplex virus type 2 meningitis, 131/171 (77%) were females. Immunosuppression [32/162 (20%)] and shingles [90/149 (60%)] were frequent in varicella-zoster virus meningitis. The triad of headache, neck stiffness and hyperacusis or photophobia was present in 264/960 (28%). The median time until lumbar puncture was 3.0 h (IQR 1.3-7.1), and the median CSF leucocyte count was 160 cells/µl (IQR 60-358). The outcome was unfavourable in 216/1055 (20%) 30 days after discharge. Using unidentified pathogen as the reference, the adjusted relative risk of an unfavourable outcome was 1.34 (95% CI 0.95-1.88) for enteroviruses, 1.55 (95% CI 1.00-2.41) for herpes simplex virus type 2, 1.51 (95% CI 0.98-2.33) for varicella-zoster virus and 1.37 (95% CI 0.61-3.05) for miscellaneous viruses. The adjusted relative risk of an unfavourable outcome was 1.34 (95% CI 1.03-1.75) for females. Timing of acyclovir or valacyclovir was not associated with the outcome in meningitis caused by herpes simplex virus type 2 or varicella-zoster virus. In summary, the outcome of viral meningitis was similar among patients with different aetiologies, including those with presumed viral meningitis but without an identified pathogen. Females had an increased risk of an unfavourable outcome. Early antiviral treatment was not associated with an improved outcome in meningitis caused by herpes simplex virus type 2 or varicella-zoster virus.

Persistent dysexecutive syndrome after pneumococcal meningitis complicated by recurrent ischemic strokes: A case report

BACKGROUND

Meningitis is a possible complication of pneumococcal infection concerning acute otitis media and sinusitis. It might compromise cognitive function, both for the infection itself and the vascular events that sometimes follow the acute phase.

CASE SUMMARY

Here we describe the case of a 32-year-old female patient admitted to the emergency room due to extensive pneumococcal meningitis as a consequence of sinus outbreak. She presented with extensive laminar ischemic damage in the acute phase, resulting in severe cognitive and behavioural impairment. Four years of follow-up, through neuropsychological assessments and neuroradiological investigations, demonstrated the presence of subsequent vascular events, 3 months and 2 years after onset.

CONCLUSION

The case is discussed in light of scientific knowledge of the long-term outcomes of this pathology in order to potentially improve diagnosis and promote better outcomes.

Epidemiological characteristics and climatic variability of viral meningitis in Kazakhstan, 2014-2019

Background

The comprehensive epidemiology and impact of climate on viral meningitis (VM) in Kazakhstan are unknown. We aimed to study the incidence, in-hospital mortality and influence of climatic indicators on VM from 2014 to 2019.

Methods

Nationwide electronic healthcare records were used to explore this study. ICD-10 codes of VM, demographics, and hospital outcomes were evaluated using descriptive statistics and survival analysis.

Results

During the 2014-2019 period, 10,251 patients with VM were admitted to the hospital. 51.35% of them were children, 57.85% were males, and 85.9% were from the urban population. Enteroviral meningitis was the main cause of VM in children. The incidence rate was 13 and 18 cases per 100,000 population in 2014 and 2019, respectively. Case fatality rate was higher in 2015 (2.3%) and 2017 (2.0%). The regression model showed 1°C increment in the daily average temperature might be associated with a 1.05-fold (95% CI 1.047-1.051) increase in the daily rate of VM cases, 1hPa increment in the average air pressure and 1% increment in the daily average humidity might contribute to a decrease in the daily rate of VM cases with IRRs of 0.997 (95% CI 0.995-0.998) and 0.982 (95% CI 0.981-0.983), respectively. In-hospital mortality was 35% higher in males compared to females. Patients residing in rural locations had a 2-fold higher risk of in-hospital death, compared to city residents. Elderly patients had a 14-fold higher risk of in-hospital mortality, compared to younger patients.

Conclusion

This is the first study in Kazakhstan investigating the epidemiology and impact of climate on VM using nationwide healthcare data. There was a tendency to decrease the incidence with outbreaks every 5 years, and mortality rates were higher for Russians and other ethnicities compared to Kazakhs, for males compared to females, for elder patients compared to younger patients, and for patients living in rural areas compared to city residents. The climatic parameters and the days of delay indicated a moderate interaction with the VM cases.

Treatment of Herpes Simplex Virus Type 2 Meningitis: A Survey Among Infectious Diseases Specialists in France, Sweden, Australia, and Denmark

Background

We aimed to describe attitudes toward treatment of herpes simplex virus type 2 (HSV-2) meningitis and prioritize future trials.

Methods

This was a self-administered online survey of HSV-2 meningitis treatment among infectious diseases (ID) specialists in France, Sweden, Australia, and Denmark.

Results

A total of 223 ID specialists (45% female) from France (36%), Denmark (24%), Sweden (21%), and Australia (19%) participated in the survey, primarily from university hospitals (64%). The estimated overall response rate was 11% and ranged from 6% (Australia) to 64% (Denmark). Intravenous (IV) acyclovir followed by oral valacyclovir was the favored treatment in 110 of 179 (61%), whereas monotherapy with either IV acyclovir or oral valacyclovir was used by 35 of 179 (20%) and 34 of 179 (19%), respectively. The median total duration was reported to be 7 days (interquartile range, 7-10 days) regardless of antiviral regimen. Immunocompromise influenced decisions on antiviral treatment in 110 of 189 (58%) of respondents, mainly by prolonged total duration of treatment (36/110 [33%]), prolonged IV administration (31/110 [28%]), and mandatory antiviral treatment (25/110 [23%]). Treatment with acyclovir/valacyclovir versus placebo and comparison of acyclovir versus valacyclovir were assigned the highest prioritization scores for future randomized controlled trials on HSV-2 meningitis.

Conclusions

Perceptions of indications for as well as type and duration of antiviral treatment varied substantially among ID specialists.

Sevoflurane exposure induces neurotoxicity by regulating mitochondrial function of microglia due to NAD insufficiency

Developmental neurons received with sevoflurane, the commonly used inhalational anesthetic agent in clinical surgery, several times tend to be destroyed. Microglia, the resident immune cells of the central nervous system (CNS), are activated after sevoflurane exposure, accompanied by releasing proinflammatory cytokines that damage developing neurons. The sevoflurane-induced neurotoxicity could be attributed to activated microglia presenting proinflammatory and anti-inflammatory functions. Proinflammatory microglia release cytokines to impair the CNS, while anti-inflammatory microglia engulf damaged neurons to maintain CNS homeostasis. Sevoflurane exposure promotes the secretion of proinflammatory cytokines by microglia, inhibiting the microglial phagocytic function. Microglia with poor phagocytic function cannot engulf damaged neurons, leading to the accumulation of damaged neurons. The mechanism underlying poor phagocytic function may be attributed to mitochondrial dysfunction of microglia induced by sevoflurane exposure, in which affected mitochondria cannot generate adequate ATP and NAD to satisfy the energy demand. We discovered that sevoflurane treatment impaired the mitochondrial metabolism of microglia, which resulted in NAD deficiency and couldn’t produce sufficient energy to clear damaged neurons to maintain CNS development. Our findings provide an explanation of a new mechanism underlying sevoflurane-induced neurotoxicity.

Herpes simplex virus 2 meningitis in adults: A prospective, nationwide, population-based cohort study

BACKGROUND

Data on the clinical presentation are scarce and prognostic factors of Herpes simplex virus type 2 (HSV-2) meningitis remain unknown.

METHODS

Prospective, nationwide, population-based database identifying all adults treated for HSV-2 meningitis at departments of infectious diseases in Denmark from 2015-2020. Unfavorable outcome was defined as Glasgow Outcome Scale (GOS) score of 1-4 and extended GOS score of 1-6. Modified Poisson regression was used to compute relative risks with 95% confidence intervals (RR, 95% CI) for unfavorable outcome.

RESULTS

HSV-2 meningitis was diagnosed in 205 cases (76% female, median age 35 [IQR 27-49]) yielding an incidence of 0.7/100,000/year. Common symptoms were headache 195/204 (95%), photo/phonophobia 143/188 (76%), and neck stiffness 106/196 (54%). Median time to lumbar puncture was 2.0 hours (IQR 1-4.8) and cerebrospinal fluid (CSF) leukocyte count was 360x10 6/L (IQR 166-670) with a mononuclear predominance of 97% (IQR 91-99). Lumbar puncture was preceded by brain imaging in 61/205 (30%). Acyclovir/valaciclovir was administered in 197/205 (96%) cases for a median of 10 days (IQR 7-14).Unfavorable outcome was observed in 64/205 (31%) at discharge and 19/181 (11%) after six months and was not associated with female sex (RR 1.08, 95% CI 0.65-1.79), age ≥35 years (1.28, 0.83-1.97), immuno-compromise (1.07, 0.57-2.03), or CSF leukocyte count >1,000x10 6/L (0.78, 0.33-1.84).

CONCLUSIONS

HSV-2 meningitis often presented as meningeal symptoms in younger females. Unfavorable outcome at discharge was common and was not associated with sex, age, immune-compromise, or CSF leukocyte count. Sequelae persisted beyond six months in one tenth of patients.

Cognitive decline following acute viral infections: literature review and projections for post-COVID-19

Recently, much attention has been drawn to the importance of the impact of infectious disease on human cognition. Several theories have been proposed, to explain the cognitive decline following an infection as well as to understand better the pathogenesis of human dementia, especially Alzheimer's disease. This article aims to review the state of the art regarding the knowledge about the impact of acute viral infections on human cognition, laying a foundation to explore the possible cognitive decline followed coronavirus disease 2019 (COVID-19). To reach this goal, we conducted a narrative review systematizing six acute viral infections as well as the current knowledge about COVID-19 and its impact on human cognition. Recent findings suggest probable short- and long-term COVID-19 impacts in cognition, even in asymptomatic individuals, which could be accounted for by direct and indirect pathways to brain dysfunction. Understanding this scenario might help clinicians and health leaders to deal better with a wave of neuropsychiatric issues that may arise following COVID-19 pandemic as well as with other acute viral infections, to alleviate the cognitive sequelae of these infections around the world.

Meningitis, meningoencephalitis and encephalitis in Bern: an observational study of 258 patients

Background

Depending on geographic location, causes of encephalitis, meningoencephalitis and meningitis vary substantially. We aimed to identify the most frequent causes, clinical presentation and long-term outcome of encephalitis, meningoencephalitis and meningitis cases treated in the Inselspital University Hospital Bern, Switzerland.

Methods

In this monocentric, observational study, we performed a retrospective review of clinical patient records for all patients treated within a 3-year period. Patients were contacted for a telephone follow-up interview and to fill out questionnaires, especially related to disturbances of sleep and wakefulness.

Results

We included 258 patients with the following conditions: encephalitis (18%), nonbacterial meningoencephalitis (42%), nonbacterial meningitis (27%) and bacterial meningoencephalitis/meningitis (13%). Herpes simplex virus (HSV) was the most common cause of encephalitis (18%); tick-borne encephalitis virus (TBEV) was the most common cause of nonbacterial meningoencephalitis (46%), enterovirus was the most common cause of nonbacterial meningitis (21%) and Streptococcus pneumoniae was the most common cause of bacterial meningoencephalitis/meningitis (49%). Overall, 35% patients remained without a known cause. After a median time of 16 months, 162 patients participated in the follow-up interview; 56% reported suffering from neurological long-term sequelae such as fatigue and/or excessive daytime sleepiness (34%), cognitive impairment and memory deficits (22%), headache (14%) and epileptic seizures (11%).

Conclusions

In the Bern region, Switzerland, TBEV was the overall most frequently detected infectious cause, with a clinical manifestation of meningoencephalitis in the majority of cases. Long-term neurological sequelae, most importantly cognitive impairment, fatigue and headache, were frequently self-reported not only in encephalitis and meningoencephalitis survivors but also in viral meningitis survivors up to 40 months after acute infection.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12883-021-02502-3.

Long-term Cognitive Outcomes in Tuberculous Meningitis

Objective

Data on cognitive changes in patients with tuberculous meningitis (TBM) are sparse. We aimed to study the cognitive profiles of patients with grade I TBM and correlate them with the cytokine values.

Methods

Prospectively, 60 patients (M:F-31:29) with grade I TBM were recruited. Clinical details were collected; CSF estimation of cytokines, neuropsychological assessment, and correlation were performed.

Results

Mean age at presentation was 32.2 years (32.2 ± 10.1), and the duration of symptoms was 29.9 days (29.9 ± 25.9), respectively. Definitive evidence of mycobacterial infection was observed in 28.3% of the patients. Mean levels of tumor necrosis factor-α (TNF-α), interferon (IFN-γ), and interleukin-6 (IL-6) were 11.57 ± 30.35, 197.02 ± 186.64, and 127.03 ± 88.71 pg/mL, respectively. TNF-α levels were significantly elevated in definitive TBM (p = 0.044). Neuropsychological tests revealed an impaired auditory verbal learning test (88.3%), followed by complex figure test (50%), spatial span test (50%), clock drawing test (48.3%), digit span test (35%), color trail tests 1 and 2 (30% and 33.3%, respectively), and animal naming test (28.3%). Elevated levels of IFN-γ and IL-6 in TBM directly correlated with the number of impaired neuropsychological tests. During follow-up, significant improvement was noticed in animal naming test (p = 0.005), clock drawing test (p = 0.003), color trail test 2 (0.02), spatial span test (p = 0.012), and digit span test (0.035). Verbal learning did not show any significant change. Overall, the neuropsychological tests showed better recovery of attention, working memory, and category fluency and showed minimal recovery of verbal learning.

Conclusions

There is subclinical evidence of cognitive impairment in patients with TBM, and this correlated with elevated cytokines. Both the frontal and temporal lobes showed varying degrees of cognitive impairment.

Enterovirus Meningitis in Adults: A Prospective Nationwide Population-Based Cohort Study

OBJECTIVE

To test the hypothesis that enterovirus meningitis (EM) is a frequent and self-limiting condition, the epidemiology of EM in adults was examined.

METHODS

Using a prospective, nationwide, population-based database, all adults with EM confirmed by PCR of the CSF from 2015 to 2019 were included. Unfavorable outcome was defined as Glasgow Outcome Scale scores of 1-4 at discharge. Modified Poisson regression was used to compute adjusted relative risks (RRs).

RESULTS

A total of 419 cases of EM in 418 adults (46% female, median age 31 years [interquartile range (IQR) 27-35]) yielded an incidence of 1.80/100,000/year. Admission diagnoses included CNS infection 247/397 (62%), other neurologic conditions 89/397 (22%), and cerebrovascular diseases 33/397 (8%). Genotype was available for 271 cases, of which echovirus 30 accounted for 155 (57%). Patients presented with headache 412/415 (99%), history of fever 303/372 (81%), photophobia 292/379 (77%), and neck stiffness 159/407 (39%). Fever (≥38.0°C) was observed in 192/399 (48%) at admission. The median CSF leukocyte count was 130 10⁶/L (range 0-2,100) with polymorphonuclear predominance (>50%) in 110/396 (28%). Cranial imaging preceded lumbar puncture in 127/417 (30%) and was associated with non-CNS infection admission diagnoses and delayed lumbar puncture (median 4.8 hours [IQR 3.4-7.9] vs 1.5 [IQR 0.8-2.8], p < 0.001). Unfavorable outcome occurred in 99/419 (24%) at discharge; more often in female patients (RR 2.30 [1.58-3.33]) and less frequent in echovirus 30 (RR 0.67 [0.46-1.00]) in adjusted analyses. Outcome remained unfavorable in 22/379 (6%) after 6 months.

CONCLUSIONS

EM is common among young, healthy adults. Although the long-term prognosis remains reassuring, a substantial proportion have moderate disability at discharge, especially female patients.

Neuronal Damage and Neuroinflammation, a Bridge Between Bacterial Meningitis and Neurodegenerative Diseases

Bacterial meningitis is an inflammation of the meninges which covers and protects the brain and the spinal cord. Such inflammation is mostly caused by blood-borne bacteria that cross the blood-brain barrier (BBB) and finally invade the brain parenchyma. Pathogens such as Streptococcus pneumoniae, Neisseria meningitidis, and Haemophilus influenzae are the main etiological causes of bacterial meningitis. After trafficking across the BBB, bacterial pathogens in the brain interact with neurons, the fundamental units of Central Nervous System, and other types of glial cells. Although the specific molecular mechanism behind the interaction between such pathogens with neurons is still under investigation, it is clear that bacterial interaction with neurons and neuroinflammatory responses within the brain leads to neuronal cell death. Furthermore, clinical studies have shown indications of meningitis-caused dementia; and a variety of neurodegenerative diseases such as Alzheimer's disease, Parkinson's disease and Huntington's disease are characterized by the loss of neurons, which, unlike many other eukaryotic cells, once dead or damaged, they are seldom replaced. The aim of this review article is to provide an overview of the knowledge on how bacterial pathogens in the brain damage neurons through direct and indirect interactions, and how the neuronal damage caused by bacterial pathogen can, in the long-term, influence the onset of neurodegenerative disorders.

Clinical implications of intraoperative eABRs to the Evo®-CI electrode array recipients

INTRODUCTION

Electrically evoked auditory brainstem responses provide reliable clinical information to assist professionals in the auditory rehabilitation of cochlear implant users.

OBJECTIVE

This study aimed to investigate intraoperative evoked auditory brainstem response recordings in Evo®-cochlear implant electrode array recipients and its correlation with their behavioral levels and auditory performance.

METHODS

This is a retrospectivey study. Intraoperative evoked auditory brainstem responses were recorded in adult Evo®-cochlear implant electrode array recipients. Wave V latencies, amplitudes and interpeak III-V intervals were recorded in three different electrode locations and compared to the sentence recognition scores obtained from subjects after six months of device use. Evoked auditory brainstem responses thresholds were also recorded and compared to the behaviorally determined levels of the subjects in the sound processor activation.

RESULTS

Evoked auditory brainstem responses thresholds were significantly correlated with both, behavioral T- and C-levels and they were recorded at audible electrical stimulation levels in all subjects. There was a significant correlation between interpeak III-V interval recorded in the apical electrode and sentence recognition scores of the subjects.

CONCLUSIONS

Intraoperative evoked auditory brainstem responses can be used to establish audible levels for fitting the sound processor in Evo®-cochlear implant recipients and it could help professionals to plan further actions aiming to improve their auditory performance.

Plasma-Treated Water Affects Listeria monocytogenes Vitality and Biofilm Structure

Background: Plasma-generated compounds (PGCs) such as plasma-processed air (PPA) or plasma-treated water (PTW) offer an increasingly important alternative for the control of microorganisms in hard-to-reach areas found in several industrial applications including the food industry. To this end, we studied the antimicrobial capacity of PTW on the vitality and biofilm formation of Listeria monocytogenes, a common foodborne pathogen. Results: Using a microwave plasma (MidiPLexc), 10 ml of deionized water was treated for 100, 300, and 900 s (pre-treatment time), after which the bacterial biofilm was exposed to the PTW for 1, 3, and 5 min (post-treatment time) for each pre-treatment time, separately. Colony-forming units (CFU) were significantly reduced by 4.7 log10 ± 0.29 log10, as well as the metabolic activity decreased by 47.9 ± 9.47% and the cell vitality by 69.5 ± 2.1%, compared to the control biofilms. LIVE/DEAD staining and fluorescence microscopy showed a positive correlation between treatment and incubation times, as well as reduction in vitality. Atomic force microscopy (AFM) indicated changes in the structure quality of the bacterial biofilm. Conclusion: These results indicate a promising antimicrobial impact of plasma-treated water on Listeria monocytogenes, which may lead to more targeted applications of plasma decontamination in the food industry in the future.

Aseptic Viral Meningitis Secondary to Herpes Simplex Virus 2 Genital Infection

Aseptic viral meningitis is the most common cause of meningitis in the United States. Most cases of herpes simplex virus meningitis are caused by herpes simplex virus type 2 (HSV-2), with HSV-1 primarily causing viral encephalitis. In this report, we present a case of aseptic meningitis generated by the HSV-2 in an immunosuppressed 35-year-old female with a recent diagnosis of genital herpes that was left untreated due to reported side effects of medication. 

Neuronal death in pneumococcal meningitis is triggered by pneumolysin and RrgA interactions with β-actin

Neuronal damage is a major consequence of bacterial meningitis, but little is known about mechanisms of bacterial interaction with neurons leading to neuronal cell death. Streptococcus pneumoniae (pneumococcus) is a leading cause of bacterial meningitis and many survivors develop neurological sequelae after the acute infection has resolved, possibly due to neuronal damage. Here, we studied mechanisms for pneumococcal interactions with neurons. Using human primary neurons, pull-down experiments and mass spectrometry, we show that pneumococci interact with the cytoskeleton protein β-actin through the pilus-1 adhesin RrgA and the cytotoxin pneumolysin (Ply), thereby promoting adhesion and invasion of neurons, and neuronal death. Using our bacteremia-derived meningitis mouse model, we observe that RrgA- and Ply-expressing pneumococci co-localize with neuronal β-actin. Using purified proteins, we show that Ply, through its cholesterol-binding domain 4, interacts with the neuronal plasma membrane, thereby increasing the exposure on the outer surface of β-actin filaments, leading to more β-actin binding sites available for RrgA binding, and thus enhanced pneumococcal interactions with neurons. Pneumococcal infection promotes neuronal death possibly due to increased intracellular Ca2+ levels depending on presence of Ply, as well as on actin cytoskeleton disassembly. STED super-resolution microscopy showed disruption of β-actin filaments in neurons infected with pneumococci expressing RrgA and Ply. Finally, neuronal death caused by pneumococcal infection could be inhibited using antibodies against β-actin. The generated data potentially helps explaining mechanisms for why pneumococci frequently cause neurological sequelae.

Long-Term Survival, Health, Social Functioning, and Education in Patients With an Enterovirus Central Nervous System Infection, Denmark, 1997-2016

BACKGROUND

The long-term clinical course of patients with an enterovirus central nervous system infection (ECI) is poorly understood.

METHODS

We performed a nationwide population-based cohort study of all Danish patients with ECI diagnosed 1997-2016 (n = 1745) and a comparison cohort from the general population individually matched on date of birth and sex (n = 17 450). Outcomes were categorized into mortality and risk of cancer and likely measures of neurological sequelae: neuropsychiatric morbidities, educational landmarks, use of hospital services, employment, receipt of disability pension, income, number of sick leave days, and nursing home residency.

RESULTS

Mortality in the first year was higher among patients with ECI (mortality rate ratio [MRR] = 10.0; 95% confidence interval [CI], 4.17-24.1), but thereafter mortality was not higher (MMR = 0.94; 95% CI, 0.47-1.86). Long-term outcomes for patients with ECI were not inferior to those of the comparison cohort for risk of cancer, epilepsy, mental and behavioral disorders, dementia, depression, school start, school marks, high school education, use of hospital services, employment, receipt of disability pension, income, days of sick leave, or nursing home residency.

CONCLUSIONS

Diagnosis of an ECI had no substantial impact on long-term survival, health, or social/educational functioning.

Oligodeoxynucleotides containing unmethylated cytosine-guanine motifs are effective immunostimulants against pneumococcal meningitis in the immunocompetent and neutropenic host

BACKGROUND

Bacterial meningitis is a fatal disease with a mortality up to 30% and neurological sequelae in one fourth of survivors. Available vaccines do not fully protect against this lethal disease. Here, we report the protective effect of synthetic oligodeoxynucleotides containing unmethylated cytosine-guanine motifs (CpG ODN) against the most frequent form of bacterial meningitis caused by Streptococcus pneumoniae.

METHODS

Three days prior to the induction of meningitis by intracerebral injection of S. pneumoniae D39, wild-type and Toll-like receptor (TLR9)^-/- mice received an intraperitoneal injection of 100 μg CpG ODN or vehicle. To render mice neutropenic, anti-Ly-6G monoclonal antibody was daily administrated starting 4 days before infection with a total of 7 injections. Kaplan-Meier survival analyses and bacteriological studies, in which mice were sacrificed 24 h and 36 h after infection, were performed.

RESULTS

Pre-treatment with 100 μg CpG ODN prolonged survival of immunocompetent and neutropenic wild-type mice but not of TLR9^-/- mice. There was a trend towards lower mortality in CpG ODN-treated immunocompetent and neutropenic wild-type mice. CpG ODN caused an increase of IL-12/IL-23p40 levels in the spleen and serum in uninfected animals. The effects of CpG ODN on bacterial concentrations and development of clinical symptoms were associated with an increased number of microglia in the CNS during the early phase of infection. Elevated concentrations of IL-12/IL-23p40 and MIP-1α correlated with lower bacterial concentrations in the blood and spleen during infection.

CONCLUSIONS

Pre-conditioning with CpG ODN strengthened the resistance of neutropenic and immunocompetent mice against S. pneumoniae meningitis in the presence of TLR9. Administration of CpG ODN decreased bacterial burden in the cerebellum and reduced the degree of bacteremia. Systemic administration of CpG ODN may help to prevent or slow the progression to sepsis of bacterial CNS infections in healthy and immunocompromised individuals even after direct inoculation of bacteria into the intracranial compartments, which can occur after sinusitis, mastoiditis, open head trauma, and surgery, including placement of an external ventricular drain.

Point-of-Care Approaches for Meningitis Diagnosis in a Low-Resource Setting (Southwestern Uganda): Observational Cohort Study Protocol of the "PI-POC" Trial

BACKGROUND

A timely differential diagnostic is essential to identify the etiology of central nervous system (CNS) infections in children, in order to facilitate targeted treatment, manage patients, and improve clinical outcome.

OBJECTIVE

The Pediatric Infection-Point-of-Care (PI-POC) trial is investigating novel methods to improve and strengthen the differential diagnostics of suspected childhood CNS infections in low-income health systems such as those in Southwestern Uganda. This will be achieved by evaluating (1) a novel DNA-based diagnostic assay for CNS infections, (2) a commercially available multiplex PCR-based meningitis/encephalitis (ME) panel for clinical use in a facility-limited laboratory setting, (3) proteomics profiling of blood from children with severe CNS infection as compared to outpatient controls with fever yet not severely ill, and (4) Myxovirus resistance protein A (MxA) as a biomarker in blood for viral CNS infection. Further changes in the etiology of childhood CNS infections after the introduction of the pneumococcal conjugate vaccine against Streptococcus pneumoniae will be investigated. In addition, the carriage and invasive rate of Neisseria meningitidis will be recorded and serotyped, and the expression of its major virulence factor (polysaccharide capsule) will be investigated.

METHODS

The PI-POC trial is a prospective observational study of children including newborns up to 12 years of age with clinical features of CNS infection, and age-/sex-matched outpatient controls with fever yet not severely ill. Participants are recruited at 2 Pediatric clinics in Mbarara, Uganda. Cerebrospinal fluid (for cases only), blood, and nasopharyngeal (NP) swabs (for both cases and controls) sampled at both clinics are analyzed at the Epicentre Research Laboratory through gold-standard methods for CNS infection diagnosis (microscopy, biochemistry, and culture) and a commercially available ME panel for multiplex PCR analyses of the cerebrospinal fluid. An additional blood sample from cases is collected on day 3 after admission. After initial clinical analyses in Mbarara, samples will be transported to Stockholm, Sweden for (1) validation analyses of a novel nucleic acid-based POC test, (2) biomarker research, and (3) serotyping and molecular characterization of S. pneumoniae and N. meningitidis.

RESULTS

A pilot study was performed from January to April 2019. The PI-POC trial enrollment of patients begun in April 2019 and will continue until September 2020, to include up to 300 cases and controls. Preliminary results from the PI-POC study are expected by the end of 2020.

CONCLUSIONS

The findings from the PI-POC study can potentially facilitate rapid etiological diagnosis of CNS infections in low-resource settings and allow for novel methods for determination of the severity of CNS infection in such environment.

TRIAL REGISTRATION

ClinicalTrials.gov NCT03900091; https://clinicaltrials.gov/ct2/show/NCT03900091.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

DERR1-10.2196/21430.

Infections of the central nervous system as a risk factor for mental disorders and cognitive impairment: A nationwide register-based study

BACKGROUND

CNS infections have been suggested as risk factors for cognitive decline and mental disorders; however, large-scale studies have been lacking regarding types and agents of CNS infections.

METHODS

We utilized the unique personal registration number to create a cohort of 1,709,867 individuals born 1977-2010. CNS infection was exposure and data were analysed with 1) cox regression analyses estimating hazard ratios (HR) for developing mental disorders and 2) binomial regression estimating relative risk (RR) for completion of 9th grade including average grade score in a sub-cohort born 1988-1998.

RESULTS

CNS infection increased the risk for developing mental disorders with a HR of 1.34 (95% CI 1.27-1.42). The highest risk observed was within the first 6 months after the CNS infection with a HR of 26.98 (95% CI 21.19-34.35). Viral CNS infections (HR 1.47, 95% CI 1.35-1.61) conferred a higher risk (p < 0.001) than bacterial (HR 1.24, 95% CI 1.15-1.35). Encephalitis (HR 1.64, 95% CI 1.41-1.90) conferred a higher risk (p < 0.001) than meningitis (HR 1.26, 95% CI 1.18-1.35). The risk was highest for organic mental disorders (HR 6.50, 95% CI 5.11-8.28) and disorders of intellectual development (HR 3.56, 95% CI 2.94-4.31), with a HR of 19.19 (95% CI 7.46-49.35) for profound disorder of intellectual development (IQ < 20). Furthermore, CNS infection decreased the RR of completing 9th grade of mandatory schooling (RR 0.89, 95% CI 0.88-0.91) and lowered average grade score for completers (p < 0.001).

CONCLUSIONS

CNS infections increased the risk for mental disorders and decreased the likelihood of completing 9th grade, indicating long-term consequences of CNS infections.

Etiology, Clinical Presentation and Incidence of Infectious Meningitis and Encephalitis in Polish Children

Little is known about the causes and the frequency of meningitis and encephalitis in Poland. We did a retrospective single-center cohort study of children under 18 years old hospitalized with infectious meningitis or encephalitis. Incidence rates were calculated using collected data from patients from the North-East Poland only. A total of 374 children hospitalized between 1 January 2015 and 31 December 2019 were included in the study. A total of 332 (89%) children had meningitis, and 42 (11%) had encephalitis. The etiology of the infection was established in 331 (89%) cases. Enteroviruses accounted for 224 (60%) of all patients. A total of 68 (18%) cases were tick-borne infections. Bacterial pathogens were detected in 26 (7%) children. The median length of hospital stay for children with enteroviral meningitis was 7 days (IQR 7–9), increasing to 11 days (8–13) in those treated with antibiotics. The incidence of meningitis was estimated to be 32.22 (95% CI, 25.33–40.98) per 100,000 and that of encephalitis to be 4.08 (95% CI, 2.07–8.02) per 100,000. By the broad use of molecular diagnostic methods, we managed to identify etiology of the infection in the majority of children. Our data suggest that thorough diagnostics of central nervous system infections are needed to rationalize treatment.

Targeting the complement system in bacterial meningitis

Bacterial meningitis is most commonly caused by Streptococcus pneumoniae and Neisseria meningitidis and continues to pose a major public health threat. Morbidity and mortality of meningitis are driven by an uncontrolled host inflammatory response. This comprehensive update evaluates the role of the complement system in upregulating and maintaining the inflammatory response in bacterial meningitis. Genetic variation studies, complement level measurements in blood and CSF, and experimental work have together led to the identification of anaphylatoxin C5a as a promising treatment target in bacterial meningitis. In animals and patients with pneumococcal meningitis, the accumulation of neutrophils in the CSF was mainly driven by C5-derived chemotactic activity and correlated positively with disease severity and outcome. In murine pneumococcal meningitis, adjunctive treatment with C5 antibodies prevented brain damage and death. Several recently developed therapeutics target C5 conversion, C5a, or its receptor C5aR. Caution is warranted because treatment with C5 antibodies such as eculizumab also inhibits the formation of the membrane attack complex, which may result in decreased meningococcal killing and increased meningococcal disease susceptibility. The use of C5a or C5aR antagonists to specifically target the harmful anaphylatoxins-induced effects, therefore, are most promising and present opportunities for a phase 2 clinical trial.

[S2k guideline for the diagnosis and therapy of zoster and post-zoster neuralgia]

Diese Leitlinie richtet sich an Dermatologen, Ophthalmologen, HNO-Ärzte, Pädiater, Neurologen, Virologen sowie Infektiologen, Anästhesisten und Allgemeinmediziner in Klinik und Praxis und dient zur Information für andere medizinische Fachrichtungen, die an der Behandlung des Zoster beteiligt sind. Darüber hinaus soll die Leitlinie Kostenträgern und politischen Entscheidungsträgern zur Orientierung dienen. Die Leitlinie wurde im formellen Konsensusverfahren (S2k) von Dermatologen, Virologen/Infektiologen, Ophthalmologen, HNO-Ärzten, Neurologen, Pädiatern und Anästhesisten/Schmerzmedizinern erstellt.

Die Leitlinie stellt einen Überblick über die klinische und molekulare Diagnostik sowie den Antigennachweis, die Antikörperkultur und Viruskultur dar. Diagnostisch besondere Situationen und komplizierte Verläufe der Erkrankung finden ebenfalls Berücksichtigung. Die antivirale Therapie des Zoster und der Postzosterneuralgie wird im Allgemeinen und für besondere Situationen dargelegt. Detaillierte Angaben zur Schmerzbehandlung finden Erwähnung und sind in einer Übersicht dargestellt. Ebenso werden die lokaltherapeutischen Maßnahmen thematisiert.

Long-term neurologic and cognitive outcome and quality of life in adults after pneumococcal meningitis

OBJECTIVES

To perform a cross-sectional cohort study on long-term neurologic, cognitive and quality-of-life outcome in adults surviving pneumococcal meningitis.

METHODS

Adult survivors of community-acquired pneumococcal meningitis from a Dutch nationwide prospective cohort study were evaluated 1 to 5 years after acute illness. The control group consisted of partners or proxies of patients. Neurologic examination was performed and cognitive domains were tested with the Vienna Test System Cognitive Basic Assessment Test set (VTS COGBAT). The Research and Development (RAND)-36 and adapted Cognitive and Emotional Consequences of Stroke (CLCE)-24 questionnaires assessed perceived cognitive functioning and quality of life. Differences between group scores were tested with multivariate analyses of variance.

RESULTS

A total of 80 pneumococcal meningitis patients and 69 controls were evaluated. After a median of 2 years (interquartile range, 2-3) after acute illness, 27 (34%) of 79 patients had persistent neurologic sequelae, most commonly hearing loss (21/79, 27%). On overall neuropsychologic evaluation, patients performed worse than the controls (MANCOVA; p 0.008), with alertness (z score -0.33, p 0.011) and cognitive flexibility (z score -0.33, p 0.027) as the most affected domains. Cognitive impairment was present in 11 (14%) of 79 patients. CLCE-24 questionnaires revealed cognitive impairment on all domains, most commonly for cognitive speed (53/75, 71%), attention (45/75, 60%) and memory (46/75, 61%). Patients had lower quality-of-life scores than controls (item physical functioning, (median) patients vs. controls, 80 vs. 95, p < 0.001; social functioning, (median) 81 vs. 100, p 0.003; perceived health, (mean) 59 vs. 70, p 0.005), which correlated with cognitive complaints (R = 0.66, p < 0.001).

CONCLUSIONS

Adults after pneumococcal meningitis are at high risk of long-term neurologic and neuropsychologic deficits impairing daily life activities and quality of life.

Encephalitis and aseptic meningitis: short-term and long-term outcome, quality of life and neuropsychological functioning

For those surviving encephalitis, the influence on daily life of patients and their relatives may be substantial. In contrast, the prognosis after aseptic meningitis (ASM) is considered good. In this prospective study in patients with encephalitis (n = 20) and ASM (n = 46), we show that both groups experienced reduced Health Related Quality of Life (HRQoL) at two months after discharge, and that workability was reduced in 37% of the patients with ASM. However, 12 months after discharge no neuropsychological deficits were detected in the ASM group, whereas patients with encephalitis had lower scores on tests of fine motor and psychomotor skills as well as on learning and memory. We also found that for patients with encephalitis, neopterin, as a marker of Th1 cell induced macrophage activation, and a putatively neurotoxic ratio of the kynurenine pathway (KP) measured during the acute phase was associated with lower HRQoL. Our data show that not only encephalitis, but also ASM has substantial short-term influence on HRQoL and workability. For patients with encephalitis we suggest a link between immune activation and activation of the KP during the acute phase with impaired HRQoL.

Incidence, aetiology, and sequelae of viral meningitis in UK adults: a multicentre prospective observational cohort study

BACKGROUND

Viral meningitis is increasingly recognised, but little is known about the frequency with which it occurs, or the causes and outcomes in the UK. We aimed to determine the incidence, causes, and sequelae in UK adults to improve the management of patients and assist in health service planning.

METHODS

We did a multicentre prospective observational cohort study of adults with suspected meningitis at 42 hospitals across England. Nested within this study, in the National Health Service (NHS) northwest region (now part of NHS England North), was an epidemiological study. Patients were eligible if they were aged 16 years or older, had clinically suspected meningitis, and either underwent a lumbar puncture or, if lumbar puncture was contraindicated, had clinically suspected meningitis and an appropriate pathogen identified either in blood culture or on blood PCR. Individuals with ventricular devices were excluded. We calculated the incidence of viral meningitis using data from patients from the northwest region only and used these data to estimate the population-standardised number of cases in the UK. Patients self-reported quality-of-life and neuropsychological outcomes, using the EuroQol EQ-5D-3L, the 36-Item Short Form Health Survey (SF-36), and the Aldenkamp and Baker neuropsychological assessment schedule, for 1 year after admission.

FINDINGS

1126 patients were enrolled between Sept 30, 2011, and Sept 30, 2014. 638 (57%) patients had meningitis: 231 (36%) cases were viral, 99 (16%) were bacterial, and 267 (42%) had an unknown cause. 41 (6%) cases had other causes. The estimated annual incidence of viral meningitis was 2·73 per 100 000 and that of bacterial meningitis was 1·24 per 100 000. The median length of hospital stay for patients with viral meningitis was 4 days (IQR 3-7), increasing to 9 days (6-12) in those treated with antivirals. Earlier lumbar puncture resulted in more patients having a specific cause identified than did those who had a delayed lumbar puncture. Compared with the age-matched UK population, patients with viral meningitis had a mean loss of 0·2 quality-adjusted life-years (SD 0·04) in that first year.

INTERPRETATION

Viruses are the most commonly identified cause of meningitis in UK adults, and lead to substantial long-term morbidity. Delays in getting a lumbar puncture and unnecessary treatment with antivirals were associated with longer hospital stays. Rapid diagnostics and rationalising treatments might reduce the burden of meningitis on health services.

FUNDING

Meningitis Research Foundation and UK National Institute for Health Research.

The cerebral protective effect and mechanism of action of vitamin B6 adjuvant ceftriaxone in experimental pneumococcal meningitis

BACKGROUND

Pneumococcal meningitis is one of the most common infectious diseases with a high-mortality rate and long-term neurological sequelae, affecting up to 50% of survivors. Pneumococcal compounds are pro-inflammatory mediators that induce an innate immune response and tryptophan degradation through the kynurenine pathway. Vitamin B6 (vitB6) is an important vitamin which acts as a cofactor at the active sites of enzymes that catalyze a great number of reactions involved in the metabolism of tryptophan through the kynurenine pathway and may thus limit the accumulation of neurotoxic metabolites and preserve the cellular energy status. The aim of this study was to investigate the neuroprotective effect of adjuvant treatment with vitB6 in pneumococcal meningitis.

METHODS

The effects of vitB6 on the clinical symptoms, the expression of kynureninase (KYN), Kynurenic acid (KYNA), nicotinamide adenine dinucleotide (NAD) and cytokines in brain tissue and memory of infant Wistar rats subjected to pneumococcal meningitis were researched. At the same time, Kynurenine 3-monooxygenase (KMO) inhibitor Ro 61-8048 was applied in order to further investigate the brain protective effect of vitB6 in bacterial meningitis.

RESULTS

Adjuvant therapy of bacterial meningitis with vitB6 could improve the clinical symptoms, learning performance, lead to the maintenance of cellular NAD+ and ATP homeostasis and significantly down-regulate the levels of cytokines in the brain tissue by affecting the KYN pathway.

CONCLUSIONS

Adjuvant treatment with vitB6 in pneumococcal meningitis could exert neuroprotective effect via increasing the preservation of cellular energy through affecting the KYN pathway and reducing of the inflammatory response.

P3 Cognitive Potential in Cochlear Implant Users

Introduction  The P3 cognitive evoked potential is recorded when a subject correctly identifies, evaluates and processes two different auditory stimuli.

Objective  to evaluate the latency and amplitude of the P3 evoked potential in 26 cochlear implant users with post-lingual deafness with good or poor speech recognition scores as compared with normal hearing subjects matched for age and educational level.

Methods  In this prospective cohort study, auditory cortical responses were recorded from 26 post-lingual deaf adult cochlear implant users (19 with good and 7 with poor speech recognition scores) and 26 control subjects.

Results  There was a significant difference in the P3 latency between cochlear implant users with poor speech recognition scores (G-) and their control group (CG) ( p  = 0.04), and between G- and cochlear implant users with good speech discrimination (G+) ( p  = 0.01). We found no significant difference in the P3 latency between the CG and G+. In this study, all G- patients had deafness due to meningitis, which suggests that higher auditory function was impaired too.

Conclusion  Post-lingual deaf adult cochlear implant users in the G- group had prolonged P3 latencies as compared with the CG and the cochlear implant users in the G+ group. The amplitudes were similar between patients and controls. All G- subjects were deaf due to meningitis. These findings suggest that meningitis may have deleterious effects not only on the peripheral auditory system but on the central auditory processing as well.

Adjuvant non-bacteriolytic and anti-inflammatory combination therapy in pneumococcal meningitis: an investigation in a mouse model

OBJECTIVES

Therapy with antibiotics, dexamethasone, and supportive intensive care has improved the prognosis of pneumococcal meningitis, but mortality remains high. Here, we investigated an adjunctive combination therapy of the non-bacteriolytic antibiotic daptomycin plus several anti-inflammatory agents to identify the currently most promising adjunctive combination therapy for pneumococcal meningitis.

METHODS

C57BL/6 mice were infected by injection of pneumococci into the cisterna magna. Treatment was begun 21 h after infection, and consisted of ceftriaxone plus (a) dexamethasone, (b) dexamethasone plus daptomycin, (c) daptomycin, (d) daptomycin plus an anti-IL1 antibody, (e) daptomycin plus roscovitine, or (f) daptomycin plus an anti-C5 antibody. Animals were followed until 45 h after infection. Furthermore, adjunctive daptomycin plus anti-C5 antibodies were assessed in a long-term follow-up.

RESULTS

Adjunctive treatment with daptomycin and an anti-C5 antibody was superior to adjunctive dexamethasone and reduced disease symptoms (clinical score 1.1 ± 1.1 versus 5.0 ± 2.7, p < 0.0083), improved explorative activity (open field test 17.8 ± 8.2 versus 7.4 ± 4.3 crossed fields/2 minutes, p < 0.0083), and reduced hearing impairment (thresholds for click stimulus 96.1 ± 14.7 versus 114.8 ± 9.3 dB SPL, p < 0.0083) in the acute stage. Furthermore, explorative activity (14.4 ± 7.3 crossed fields/2 minutes versus 6.3 ± 7.2, p < 0.05) and cognitive function (t-maze test, exploration time previously unknown alley 72.4 ± 14.3 versus 48.7 ± 25.6%, p < 0.05) was improved at 2 weeks after infection. Treatment with daptomycin plus an anti-IL-1β antibody or roscovitine was not of significant benefit in comparison to adjunctive therapy with dexamethasone.

CONCLUSIONS

An adjunctive combination of the non-lytic antibiotic daptomycin plus an anti-C5 antibody was superior to standard therapy with adjunctive dexamethasone in the treatment of pneumococcal meningitis.

Infectious meningitis and encephalitis in adults in Denmark: a prospective nationwide observational cohort study (DASGIB)

OBJECTIVES

To monitor epidemiological trends of infectious meningitis (bacterial and viral) and encephalitis in Denmark.

METHODS

Nationwide prospective observational study of all cases of proven community-acquired infectious meningitis and encephalitis in adults treated in all infectious diseases departments in Denmark from 1 January 2015 to 30 June 2016. We included data on symptoms, aetiology, treatment and outcome assessed by the Glasgow Outcome Scale (GOS) 30 days after discharge. GOS 1-4 was categorized as unfavourable outcome.

RESULTS

During 18 months of observation, we identified 252 cases of viral meningitis (3.6/100 000/year), 214 cases of bacterial meningitis (3.1/100 000/year) and 96 cases of infectious encephalitis (1.4/100 000/year). In bacterial meningitis, Streptococcus pneumoniae was the most frequent infectious agent (n = 101) followed by Staphylococcus aureus (n = 24) and β-haemolytic streptococci (n = 14). Meningococcal meningitis was rare (n = 11). In encephalitis, herpes simplex virus type 1 was most common (n = 37) followed by varicella zoster virus (n = 20), whereas varicella zoster virus (n = 61) was most common in viral meningitis followed by enterovirus (n = 50) and herpes simplex virus type 2 (n = 46). Case fatality and unfavourable outcome occurred in 31/214 (15%) and 96/214 (45%) with bacterial meningitis and in 5/96 (5%) and 55/89 (62%) with encephalitis. For viral meningitis, unfavourable outcome occurred in 41/252 (17%).

CONCLUSIONS

The epidemiology and clinical presentation of the examined central nervous system infections differed considerably and bacterial meningitis was more frequent than previously estimated. Overall prognosis remains poor for bacterial meningitis and encephalitis. Prospective nationwide clinical databases of central nervous system infections may be superior to epidemiological monitoring based on notifications or laboratory systems.

Understanding Etiology of Hearing Loss as a Contributor to Language Dysfluency and its Impact on Assessment and Treatment of People who are Deaf in Mental Health Settings

Working with individuals who are deaf in mental health settings can be complex work, necessitating consideration for the difference in language abilities. These differences include not only the language differences of American Sign Language (ASL) and English, but also the range of heterogeneity within the Deaf Community. Multiple influences such as mental illness, medical conditions, language deprivation and the etiology of deafness can impact how a person acquires and uses language. This article will discuss how various causes of deafness create the potential for specific language dysfluencies with individuals who are deaf in mental health settings. The article will also discuss the use of communication assessments to examine specific language dysfluency patterns and attempt to offer possible corresponding interventions.

Prevention of Memory Impairment and Neurotrophic Factors Increased by Lithium in Wistar Rats Submitted to Pneumococcal Meningitis Model

The aim of this study was to investigate the effects of lithium on brain-derived neurotrophic factor (BDNF), nerve growth factor (NGF), and glial cell line-derived neurotrophic factor (GDNF) expression in the hippocampus and on memory in experimental pneumococcal meningitis. The mood-stabilizer lithium is known as a neuroprotective agent with many effects on the brain. In this study, animals received either artificial cerebrospinal fluid or Streptococcus pneumoniae suspension at a concentration of 5 × 10⁹ CFU/mL. Eighteen hours after induction, all animals received ceftriaxone. The animals received saline or lithium (47.5 mg/kg) or tamoxifen (1 mg/kg) as adjuvant treatment, and they were separated into six groups: control/saline, control/lithium, control/tamoxifen, meningitis/saline, meningitis/lithium, and meningitis/tamoxifen. Ten days after meningitis induction, animals were subjected to open-field habituation and the step-down inhibitory avoidance tasks. Immediately after these tasks, the animals were killed and their hippocampus was removed to evaluate the expression of BDNF, NGF, and GDNF. In the meningitis group, treatment with lithium and tamoxifen resulted in improvement in memory. Meningitis group showed decreased expression of BDNF and GDNF in the hippocampus while lithium reestablished the neurotrophin expression. Lithium was able to prevent memory impairment and reestablishes hippocampal neurotrophin expression in experimental pneumococcal meningitis.

CX3CR1+ monocytes modulate learning and learning-dependent dendritic spine remodeling via TNF-α

Impaired learning and cognitive function often occurs during systemic infection or inflammation. Although activation of the innate immune system has been linked to the behavioral and cognitive effects that are associated with infection, the underlying mechanisms remain poorly understood. Here we mimicked viral immune activation with poly(I:C), a synthetic analog of double-stranded RNA, and longitudinally imaged postsynaptic dendritic spines of layer V pyramidal neurons in the mouse primary motor cortex using two-photon microscopy. We found that peripheral immune activation caused dendritic spine loss, impairments in learning-dependent dendritic spine formation and deficits in multiple learning tasks in mice. These observed synaptic alterations in the cortex were mediated by peripheral-monocyte-derived cells and did not require microglial function in the central nervous system. Furthermore, activation of CX₃CR1^highLy6C^low monocytes impaired motor learning and learning-related dendritic spine plasticity through tumor necrosis factor (TNF)-α-dependent mechanisms. Taken together, our results highlight CX₃CR1^high monocytes and TNF-α as potential therapeutic targets for preventing infection-induced cognitive dysfunction.

Role of neural barriers in the pathogenesis and outcome of Streptococcus pneumoniae meningitis

Bacterial meningitis is an inflammatory disease of the meninges of the central nervous system (CNS). Streptococcus pneumoniae (S. pneumoniae), Neisseria meningitidis, and Haemophilus influenzae are the major bacterial pathogens causing meningitis with S. pneumoniae being responsible for two thirds of meningitis cases in the developed world. To reach the CNS following nasopharyngeal colonization and bacteraemia, the bacteria traverse from the circulation across the blood brain barrier (BBB) and choroid plexus. While the BBB has a protective role in healthy individuals by shielding the CNS from neurotoxic substances circulating in the blood and maintaining the homeostasis within the brain environment, dysfunction of the BBB is associated with the pathophysiology of numerous neurologic disorders, including bacterial meningitis. Inflammatory processes, including release of a broad range of cytokines and free radicals, further increase vascular permeability and contribute to the excessive neural damage observed. Injury to the cerebral microvasculature and loss of blood flow auto-regulation promote increased intracranial pressure and may lead to vascular occlusion. Other common complications commonly associated with meningitis include abnormal neuronal hyper-excitability (e.g., seizures) and loss of hearing. Despite the existence of antibiotic treatment and adjuvant therapy, the relatively high mortality rate and the severe outcomes among survivors of pneumococcal meningitis in developing and developed countries increase the urgency in the requirement of discovering novel biomarkers for the early diagnosis as well as novel treatment approaches. The present review aimed to explore the changes in the brain vascular barriers, which allow S. pneumoniae to invade the CNS, and describe the resultant brain injuries following bacterial meningitis.

Hearing performance as a predictor of postural recovery in cochlear implant users

Objective

This study aimed to evaluate if hearing performance is a predictor of postural control in cochlear implant (CI) users at least six months after surgery.

Methods

Cross-sectional study including (CI) recipients with post-lingual deafness and controls who were divided into the following groups: nine CI users with good hearing performance (G+), five CI users with poor hearing performance (G−), and seven controls (CG). For each patient, computerized dynamic posturography (CDP) tests, a sensory organization test (SOT), and an adaptation test (ADT) were applied as dual task performance, with first test (FT) and re-test (RT) on the same day, including a 40–60 min interval between them to evaluate the short-term learning ability on postural recovery strategies. The results of the groups were compared.

Results

Comparing the dual task performance on CDP and the weighted average between all test conditions, the G+ group showed better performance on RT in SOT4, SOT5, SOT6, and CS, which was not observed for G− and CG. The G− group had significantly lower levels of short-term learning ability than the other two groups in SOT5 (p = 0.021), SOT6 (p = 0.025), and CS (p = 0.031).

Conclusion

The CI users with good hearing performance had a higher index of postural recovery when compared to CI users with poor hearing performance.

Bacterial Peptidoglycan Traverses the Placenta to Induce Fetal Neuroproliferation and Aberrant Postnatal Behavior

Maternal infection during pregnancy is associated with adverse outcomes for the fetus, including postnatal cognitive disorders. However, the underlying mechanisms are obscure. We find that bacterial cell wall peptidoglycan (CW), a universal PAMP for TLR2, traverses the murine placenta into the developing fetal brain. In contrast to adults, CW-exposed fetal brains did not show any signs of inflammation or neuronal death. Instead, the neuronal transcription factor FoxG1 was induced, and neuroproliferation leading to a 50% greater density of neurons in the cortical plate was observed. Bacterial infection of pregnant dams, followed by antibiotic treatment, which releases CW, yielded the same result. Neuroproliferation required TLR2 and was recapitulated in vitro with fetal neuronal precursor cells and TLR2/6, but not TLR2/1, ligands. The fetal neuroproliferative response correlated with abnormal cognitive behavior in CW-exposed pups following birth. Thus, the bacterial CW-TLR2 signaling axis affects fetal neurodevelopment and may underlie postnatal cognitive disorders.

The UK joint specialist societies guideline on the diagnosis and management of acute meningitis and meningococcal sepsis in immunocompetent adults

Bacterial meningitis and meningococcal sepsis are rare conditions with high case fatality rates. Early recognition and prompt treatment saves lives. In 1999 the British Infection Society produced a consensus statement for the management of immunocompetent adults with meningitis and meningococcal sepsis. Since 1999 there have been many changes. We therefore set out to produce revised guidelines which provide a standardised evidence-based approach to the management of acute community acquired meningitis and meningococcal sepsis in adults. A working party consisting of infectious diseases physicians, neurologists, acute physicians, intensivists, microbiologists, public health experts and patient group representatives was formed. Key questions were identified and the literature reviewed. All recommendations were graded and agreed upon by the working party. The guidelines, which for the first time include viral meningitis, are written in accordance with the AGREE 2 tool and recommendations graded according to the GRADE system. Main changes from the original statement include the indications for pre-hospital antibiotics, timing of the lumbar puncture and the indications for neuroimaging. The list of investigations has been updated and more emphasis is placed on molecular diagnosis. Approaches to both antibiotic and steroid therapy have been revised. Several recommendations have been given regarding the follow-up of patients.

Patterns of Local and Systemic Cytokines in Bacterial Meningitis and its Relation with Severity and Long-Term Sequelae

Bacterial meningitis (BM) is a pyogenic infection present in the subarachnoid space, potentially fatal and frequently associated with neurological sequelae. During BM, cytokines (CTs) are locally produced. We sought to determine the CTs' clinical role as disease severity predictors in adults, which is not completely clear. Using a bead-based flow cytometric assay, levels of six CTs were determined in cerebrospinal fluid (CSF) and plasma from 18 adult BM patients and 19 uninfected controls. Long-term neurological sequelae were evaluated using the Glasgow Outcome Scale (GOS). All evaluated CTs were higher in CSF than in plasma, and the levels of CSF interleukin (IL)-6, IL-8, IL-10, IL-1β, and tumor necrosis factor-α and plasma IL-10 and IL-12p70 were significantly higher in patients with severe sepsis than with sepsis, suggesting an association with clinical severity. There was a strong negative correlation between CSF IL-6 and plasma IL-12p70 with GOS score, supporting the possible role of these CTs in the development of neurological long-term sequelae. These findings could be helpful to identify candidates to receive neuroprotective treatments and early physiotherapy schemes.

Clinical Presentation, Aetiology, and Outcomes of Meningitis in a Setting of High HIV and TB Prevalence

Meningitis causes significant morbidity and mortality globally. The aim of this study was to study the clinical presentation, aetiology, and outcomes of meningitis among adult patients admitted to Queen Mamohato Memorial Hospital in Maseru, Lesotho, with a diagnosis of meningitis. A cross-sectional study was conducted between February and April 2014; data collected included presenting signs and symptoms, laboratory results, and clinical outcomes. Descriptive statistics were used to summarise data; association between variables was analysed using Fisher's exact test. 56 patients were enrolled; the HIV coinfection rate was 79%. The most common presenting symptoms were altered mental status, neck stiffness, headache, and fever. TB meningitis was the most frequent diagnosis (39%), followed by bacterial (27%), viral (18%), and cryptococcal meningitis (16%). In-hospital mortality was 43% with case fatalities of 23%, 40%, 44%, and 90% for TB, bacterial, cryptococcal, and viral meningitis, respectively. Severe renal impairment was significantly associated with mortality. In conclusion, the causes of meningitis in this study reflect the high prevalence of HIV and TB in our setting. Strategies to reduce morbidity and mortality due to meningitis should include improving diagnostic services to facilitate early detection and treatment of meningitis and timely initiation of antiretroviral therapy in HIV-infected patients.

Neurocognitive functions and brain atrophy after proven neuroborreliosis: a case-control study

Background

Patients often report neurocognitive difficulties after neuroborreliosis (NB). The frequency and extent of cognitive problems in European patients have been studied incompletely.

Methods

Sixty patients received a neurological and neuropsychological work-up 6 months or longer after treatment for proven NB. Quality of life, psychiatric symptom load, and brain atrophy were measured. All results were compared with a group of 30 healthy control persons adapted for age, gender and education being serologically negative for Borrelia burgdorferi senso latu. A cognitive sum score and a global sum score including cognitive, psychological results and quality of life data was calculated for both groups.

Results

Patients after NB showed a lower (i.e. more impaired) score on the Scripps Neurological rating scale (SNRS), but the observed neurological deficits were generally mild (mean ± SD: 97.1 ± 4.7 vs. 99.1 ± 2.4, p = 0.02). The mean neuropsychological domain results of the NB group were all within the normal range. However, a lower performance was found for the frontal executive function z-values (mean ± SD –0.29 ± 0.60 vs. 0.09 ± 0.60; p = 0.0059) of NB patients. Comparing the global sum score (mean ± SD 11.3 ± 4.2 _NB vs. 14.3 ± 2.9 _control, p = 0.001) and the cognitive sum score of the NB group with those of the control group (mean ± SD -0.15 ± 0.42 _NB vs. 0.08 ± 0.31 _control, p = 0.0079), both differences were statistically different. The frequencies of impaired global sum scores and those of the pathological cognitive sum scores (p = 0.07) did not differ statistically. No significant differences were found for health-related quality of life (hrQoL), sleep, psychiatric symptom load, or brain atrophy.

Conclusion

The mean cognitive functions of patients after proven NB were in the normal range. However, we were able to demonstrate a lower performance for the domain of frontal executive functions, for the mean cognitive sum score and the global sum score as a sign of subtle but measurable sequelae of neuroborreliosis. Brain atrophy is not a common consequence of neuroborreliosis.

The outcomes of children with pediatric acute respiratory distress syndrome: proceedings from the Pediatric Acute Lung Injury Consensus Conference

OBJECTIVE

To provide additional details and evidence behind the recommendations for outcomes assessment of patients with pediatric acute respiratory distress syndrome from the Pediatric Acute Lung Injury Consensus Conference.

DESIGN

Consensus conference of experts in pediatric acute lung injury.

METHODS

A panel of 27 experts met over the course of 2 years to develop a taxonomy to define pediatric acute respiratory distress syndrome and to make recommendations regarding treatment and research priorities. The outcomes subgroup comprised four experts. When published data were lacking, a modified Delphi approach emphasizing strong professional agreement was used.

RESULTS

The Pediatric Acute Lung Injury Consensus Conference experts developed and voted on a total of 151 recommendations addressing the topics related to pediatric acute respiratory distress syndrome, seven of which related to outcomes after pediatric acute respiratory distress syndrome. All seven recommendations had strong agreement. Children with acute respiratory distress syndrome continue to have a high mortality, specifically, in relation to certain comorbidities and etiologies related to pediatric acute respiratory distress syndrome. Comorbid conditions, such as an immunocompromised state, increase the risk of mortality even further. Likewise, certain etiologies, such as non-pulmonary sepsis, also place children at a higher risk of mortality. Significant long-term effects were reported in adult survivors of acute respiratory distress syndrome: diminished lung function and exercise tolerance, reduced quality of life, and diminished neurocognitive function. Little knowledge of long-term outcomes exists in children who survive pediatric acute respiratory distress syndrome. Characterization of the longer term consequences of pediatric acute respiratory distress syndrome in children is vital to help identify opportunities for improved therapeutic and rehabilitative strategies that will lessen the long-term burden of pediatric acute respiratory distress syndrome and improve the quality of life in children.

CONCLUSIONS

The Consensus Conference developed pediatric-specific recommendations for pediatric acute respiratory distress syndrome regarding outcome measures and future research priorities. These recommendations are intended to promote optimization and consistency of care for children with pediatric acute respiratory distress syndrome and identify areas of uncertainty requiring further investigation.

Employment and disability pension after central nervous system infections in adults

In this nationwide population-based cohort study using national Danish registries, in the period 1980-2008, our aim was to study employment and receipt of disability pension after central nervous system infections. All patients diagnosed between 20 and 55 years of age with meningococcal (n = 451), pneumococcal (n = 553), or viral (n = 1,433) meningitis or with herpes simplex encephalitis (n = 115), who were alive 1 year after diagnosis, were identified. Comparison cohorts were drawn from the general population, and their members were individually matched on age and sex to patients. Five years after diagnosis, the differences in probability of being employed as a former patient with pneumococcal meningitis or herpes simplex encephalitis versus being a member of the comparison cohorts were -19.9% (95% confidence interval (CI): -24.7, -15.1) and -21.1% (95% CI: -33.0, -9.3), respectively, and the corresponding differences in probability of receiving disability pension were 20.2% (95% CI: 13.7, 26.7) and 16.2% (95% CI: 6.2, 26.3). The differences in probability of being employed or receiving disability pension in former meningococcal or viral meningitis patients versus members of the comparison cohorts were small. In conclusion, pneumococcal meningitis and herpes simplex encephalitis were associated with substantially decreased employment and increased need for disability pension. These associations did not seem to apply to meningococcal meningitis or viral meningitis.

Decompressive craniectomy and early cranioplasty in a 15-year-old boy with N. meningitidis meningitis

Background:

Intracranial hypertension is a well-known life-threatening complication of bacterial meningitis. Investigations on decompressive craniectomy after failure of conservative management are scarce, but this surgical treatment should be considered and performed expeditiously, as it lowers the intracranial pressure and improves brain tissue oxygenation. Early cranioplasty can further aid the rehabilitation.

Case Description:

A 15-year-old boy was admitted to our emergency department because of sudden onset of neurologic decline and consecutive loss of consciousness. Clinical examination and imaging showed elevated intracranial pressure, leading to the suspected diagnosis of meningitis. Intracranial pressure monitoring was installed, but the initiated conservative management failed. Finally, the patient underwent bilateral decompressive craniectomy. The microbiological test showed growth of Neisseria meningitidis. After full neurologic recovery, cranioplasty with two CAD/CAM titanium implants was conducted successfully.

Conclusions:

This unique report shows that decompressive craniotomy with duroplasty may be a crucial therapeutic approach in bacterial meningitis with refractory increased intracranial pressure and brainstem compression. Early cranioplasty with a patient-specific implant allowed the early and full reintegration of the patient.