ABSTRACT
The development of a tractable small animal model faithfully reproducing human coronavirus disease 2019 pathogenesis would arguably meet a pressing need in biomedical research. Thus far, most investigators have used transgenic mice expressing the human ACE2 in epithelial cells (K18-hACE2 transgenic mice) that are intranasally instilled with a liquid severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) suspension under deep anesthesia. Unfortunately, this experimental approach results in disproportionate high central nervous system infection leading to fatal encephalitis, which is rarely observed in humans and severely limits this model's usefulness. Here, we describe the use of an inhalation tower system that allows exposure of unanesthetized mice to aerosolized virus under controlled conditions. Aerosol exposure of K18-hACE2 transgenic mice to SARS-CoV-2 resulted in robust viral replication in the respiratory tract, anosmia, and airway obstruction but did not lead to fatal viral neuroinvasion. When compared with intranasal inoculation, aerosol infection resulted in a more pronounced lung pathology including increased immune infiltration, fibrin deposition, and a transcriptional signature comparable to that observed in SARS-CoV-2infected patients. This model may prove useful for studies of viral transmission, disease pathogenesis (including long-term consequences of SARS-CoV-2 infection), and therapeutic interventions.
Subject(s)
Angiotensin-Converting Enzyme 2/genetics , COVID-19/physiopathology , Disease Models, Animal , Encephalitis, Viral/prevention & control , Keratin-18/genetics , Nasal Sprays , SARS-CoV-2/physiology , Administration, Inhalation , Angiotensin-Converting Enzyme 2/metabolism , Animals , COVID-19/immunology , COVID-19/virology , Encephalitis, Viral/mortality , Epithelial Cells/metabolism , Female , Humans , Keratin-18/metabolism , Lung/immunology , Lung/pathology , Lung/physiopathology , Male , Mice , Mice, Transgenic , Promoter Regions, Genetic/genetics , Transcriptome , Virus ReplicationABSTRACT
Neurological diseases in cattle can be caused by several infectious agents. Astroviruses are increasingly recognized as the causative agent of encephalitis in various animals, including humans. In this study, a neuroinvasive astrovirus (BoAstV 20B05) was discovered in the brain tissues of an 81-month-old Korean native cattle with neurological symptoms. Lymphocyte infiltration and multifocal perivascular cuffing were observed in the cerebrum and brain stem, and viral antigens were also detected in the meninges. In particular, the concentration of the astroviral genome was high in the brain tissues. Korean BoAstV 20B05 was classified into the CH13/NeuroS1 clade and was closely related to the Neuro-Uy and KagoshimaSR28-462 strains. Our evolutionary analysis showed that Korean BoAstV 20B05 belongs to the sub-lineage NeuroS1 and evolved independently of BoAstV KagoshimaSR28-462. These results suggest that neuroinvasive astroviruses were first introduced in Korea. However, analysis is limited by the lack of reference astrovirus sequences reported in various countries within Asia, and further analysis should be performed using more strains. In this study, we identified a neuroinvasive astrovirus infection with neurological symptoms for the first time in South Korea and confirmed that BoAstV 20B05 may have been introduced in South Korea a long time ago.
Subject(s)
Astroviridae Infections/diagnosis , Encephalitis, Viral/diagnosis , Encephalitis, Viral/veterinary , Meningoencephalitis/veterinary , Animals , Astroviridae Infections/complications , Astroviridae Infections/mortality , Brain/pathology , Brain/virology , Cattle , Cattle Diseases/diagnosis , Cattle Diseases/virology , Encephalitis, Viral/classification , Encephalitis, Viral/mortality , Meningoencephalitis/mortality , Meningoencephalitis/virology , Phylogeny , Republic of KoreaABSTRACT
ABSTRACT: Although influenza is generally an acute, self-limited, and uncomplicated disease in healthy children, it can result in severe morbidity and mortality. The objectives of this study were to analyze and compare the clinical features and outcome of severe pediatric influenza with and without central nervous system (CNS) involvement.We conducted a retrospective observational study of children admitted to the pediatric intensive care unit (PICU) of China Medical University Children's Hospital in Taiwan with a confirmed diagnosis of influenza. The demographic data, clinical and laboratory presentations, therapeutic strategies, and neurodevelopmental outcomes for these patients were analyzed. Furthermore, comparison of patients with and without CNS involvement was conducted.A total of 32 children with severe influenza were admitted during the study periods. Sixteen children were categorized as the non-CNS (nCNS) group and 16 children were categorized as the CNS group. Nine of them had underlying disease. The most common complication in the nCNS group was acute respiratory distress syndrome, (nâ=â8/16), followed by pneumonia (nâ=â7/16, 44%). In the CNS group, the most lethal complication was acute necrotizing encephalopathy (nâ=â3/16) which led to 3 deaths. The overall mortality rate was higher in the CNS group (nâ=â6) than in the nCNS group (nâ=â1) (37.5% vs 6.25%, Pâ=â.03).The mortality rate of severe complicated influenza was significantly higher with CNS involvement. Children with primary cardiopulmonary abnormalities were at high risk of developing severe complicated influenza, while previously healthy children exhibited risk for influenza-associated encephalitis/encephalopathy.
Subject(s)
Encephalitis, Viral , Influenza, Human , Intensive Care Units, Pediatric/statistics & numerical data , Neurodevelopmental Disorders , Central Nervous System/virology , Child , Encephalitis, Viral/diagnosis , Encephalitis, Viral/etiology , Encephalitis, Viral/mortality , Female , Humans , Influenza A virus/isolation & purification , Influenza, Human/epidemiology , Influenza, Human/physiopathology , Influenza, Human/therapy , Influenza, Human/virology , Male , Mortality , Neurodevelopmental Disorders/diagnosis , Neurodevelopmental Disorders/epidemiology , Neurodevelopmental Disorders/etiology , Outcome and Process Assessment, Health Care , Retrospective Studies , Risk Factors , Severity of Illness Index , Taiwan/epidemiologyABSTRACT
BACKGROUND: Limited data are available on childhood encephalitis. Our study aimed to increase insight on clinical presentation, etiology, and clinical outcome of children with severe encephalitis in the Netherlands. METHODS: We identified patients through the Dutch Pediatric Intensive Care Evaluation database and included children diagnosed with encephalitis <18 years of age admitted to 1 of the 8 pediatric intensive care units (PICU) in the Netherlands between January 2003 and December 2013. We analyzed demographic characteristics, clinical symptoms, neurologic imaging, etiology, treatment and mortality. RESULTS: We included 121 children with a median age of 4.6 years (IQR 1.3-9.8). The most frequently described clinical features were headache (82.1%), decreased consciousness (79.8%) and seizures (69.8%). In 44.6% of the children, no causative agent was identified. Viral- and immune-mediated encephalitis were diagnosed in 33.1% and 10.7% of the patients. A herpes simplex virus infection (13.2%) was mainly seen in children <5 years of age, median age, 1.73 years (IQR 0.77-5.01), while immune-mediated encephalitis mostly affected older children, median age of 10.4 years (IQR, 3.72-14.18). An age of ≥ 5 years at initial presentation was associated with a lower mortality (OR 0.2 [CI 0.08-0.78]). The detection of a bacterial (OR 9.4 [CI 2.18-40.46]) or viral (OR 3.7 [CI 1.16-11.73]) pathogen was associated with a higher mortality. CONCLUSIONS: In almost half of the Dutch children presenting with severe encephalitis, a causative pathogen could not be identified, underlining the need for enhancement of microbiologic diagnostics. The detection of a bacterial or viral pathogen was associated with a higher mortality.
Subject(s)
Encephalitis, Viral/epidemiology , Encephalitis/epidemiology , Encephalitis/etiology , Infectious Encephalitis/epidemiology , Intensive Care Units, Pediatric/statistics & numerical data , Child , Child, Preschool , Encephalitis/mortality , Encephalitis, Viral/diagnosis , Encephalitis, Viral/mortality , Female , Hospitalization/statistics & numerical data , Humans , Infant , Infectious Encephalitis/diagnosis , Infectious Encephalitis/mortality , Male , Netherlands/epidemiology , Retrospective Studies , Severity of Illness IndexABSTRACT
Introduction. Previous studies of viral encephalitis have focused on acute costs, estimating incidence at 7.3 per 100â000 and total US annual charges at $2 billion in 2010.Aim. We aim to quantify the most updated longitudinal health economic impact of viral encephalitis in the USA from 2008 to 2015.Methodology. Data on patients diagnosed with viral encephalitis were obtained from the Truven Health Analytics MarketScan database. Patients with a primary diagnosis of viral encephalitis, from herpetic viruses and other viral aetiologies (e.g. West Nile fever) were included in the analysis. Data concerning healthcare resource utilization, inpatient mortality, length of stay and accrued healthcare costs were collected for up to 5 years.Results. Among 3985 patients with continuous enrolment for 13 months prior to the encephalitis diagnosis, more non-herpes simplex encephalitis (61.7â%) than herpes simplex encephalitis (HSE; 38.3â%) cases were recorded, with the majority concentrated in the southern USA (29.2â%). One-year inpatient mortality was 6.2â%, which over a 5-year period rose to 8.9â% for HSE and 5.8â% for all other viral encephalitides. HSE resulted in longer cumulative stays in the hospital (11 days vs. 4 days; P=0.0025), and accrued 37â% higher first-year costs, after adjusting for known confounders [P<0.001, cost ratio=1.37, 95â% confidence interval (1.20, 1.57)]. Additionally, HSE was associated with greater 5-year cumulative median charges ($125â338 vs. $82â317, P=0.0015).Conclusion. The health economic impact and long-term morbidity of viral encephalitis in the USA are substantial.
Subject(s)
Encephalitis, Viral/economics , Adult , Aged , Encephalitis, Viral/diagnosis , Encephalitis, Viral/mortality , Encephalitis, Viral/virology , Female , Health Care Costs , Humans , Male , Middle Aged , Retrospective Studies , United States , Young AdultABSTRACT
The standard for diagnosing meningoencephalitis includes cerebrospinal fluid (CSF) culture and viral polymerase chain reaction (PCR). Approval of the FilmArray® BioFire® Meningitis/Encephalitis (ME) panel has reduced time to detection of several pathogens and improved diagnostic sensitivity. The objective of this study was to determine the impact on intravenous (IV) acyclovir duration of the ME panel compared to previously utilized CSF studies within a large health system with a central laboratory. A multicenter quasi-experimental cohort study of adult and pediatric patients was conducted (n = 208). The primary endpoint was duration of IV acyclovir, which was decreased (41.6 v. 30.8 hours; P < 0.01) with the ME panel. Secondary outcomes including test-turnaround time (TAT) and the impact of utilizing a central laboratory were explored. Subgroup analyses demonstrated that number of daily couriers from hospital to the central laboratory (0 versus 7 versus 3 versus 2 couriers) and hospital distance from the central laboratory (0 versus 1-10 versus 11-20 versus 21-30 miles) significantly impacted TAT (P < 0.01). While duration of IV acyclovir for the entire healthcare system was reduced, the duration at individual sites was not impacted by number of couriers or distance from the central laboratory.
Subject(s)
Acyclovir/administration & dosage , Antiviral Agents/administration & dosage , Encephalitis, Viral/diagnosis , Encephalitis, Viral/drug therapy , Meningitis, Viral/diagnosis , Meningitis, Viral/drug therapy , Multiplex Polymerase Chain Reaction/methods , Administration, Intravenous , Adult , Age Factors , Algorithms , Child , Child, Preschool , Disease Management , Encephalitis, Viral/mortality , Encephalitis, Viral/virology , Female , Humans , Male , Meningitis, Viral/mortality , Meningitis, Viral/virology , Multiplex Polymerase Chain Reaction/standards , Prognosis , Retrospective Studies , Time Factors , Treatment OutcomeABSTRACT
BACKGROUND: Human herpesvirus (HHV)-6B encephalitis has been recognized as a serious complication after allogeneic hematopoietic cell transplantation (allo-HCT). Little is known about the pathogenic mechanism for its progression. STUDY DESIGN: We retrospectively evaluated the 16 kinds of cytokines and chemokines in cerebrospinal fluid (CSF) and plasma in patients who developed HHV-6B encephalitis. Among a total of 20 patients, 12 were categorized as the poor prognosis group (died of encephalitis; n = 8 and retained sequelae; n = 4), and other eight patients were categorized as the good prognosis group (complete recovery; n = 8). RESULTS: Concentrations of CSF IL-6 and IL-8 at the onset of encephalitis were significantly higher in the poor prognosis group than in the good prognosis group (median CSF IL-6, 28.27 pg/mL vs 14.32 pg/mL, P = .004; median CSF IL-8, 128.70 pg/mL vs 59.43 pg/mL, P = .043). Regarding plasma, the concentration of each cytokine at the onset of encephalitis was not significantly different between the two groups, except IL-5. However, higher levels of IL-6, IL-7, and MCP-1 and lower levels of IL-12 were observed 1 week before the development of encephalitis in patients with poor prognosis (median IL-6; 464.17 pg/mL vs 47.82 pg/mL, P = .02; median IL-12; 1.63 pg/mL vs 6.57 pg/mL, P = .03). CONCLUSION: We found that one week before onset of HHV-6B encephalitis, poor prognosis patients had high plasma concentrations of IL-6, IL-7, and MCP-1 and low concentrations of IL-12. At the onset of encephalitis, high concentrations of IL-6 and IL-8 in CSF were more common in the poor prognosis group, consistent with other evidence that IL-6 can have a role in CNS disturbances. Our findings show that specific cytokine status is associated with severe brain damage in patients with HHV-6B encephalitis, demonstrate prognostic value of plasma IL-6 concentrations, and suggest evaluation of anti-cytokine therapeutics in patients with HHV-6B encephalitis.
Subject(s)
Cytokines/analysis , Encephalitis, Viral/mortality , Hematopoietic Stem Cell Transplantation/adverse effects , Herpesvirus 6, Human/isolation & purification , Roseolovirus Infections/mortality , Adult , Cytokines/immunology , Encephalitis, Viral/blood , Encephalitis, Viral/cerebrospinal fluid , Encephalitis, Viral/virology , Female , Herpesvirus 6, Human/immunology , Humans , Male , Middle Aged , Prognosis , Retrospective Studies , Roseolovirus Infections/blood , Roseolovirus Infections/cerebrospinal fluid , Roseolovirus Infections/virology , Transplantation, Homologous/adverse effectsABSTRACT
BACKGROUND: A wide range of Nipah virus (NiV) encephalitis case fatality rates (CFR) have been reported. Data on the involvement of several potential risk factors in Nipah virus transmission remain controversial. We performed a systematic review and meta-analysis to estimate the pooled CFR of NiV encephalitis and to assess the risk factors for NiV infection. METHODS: Articles published up to the 27thof November 2018 in MedLine, Embase and Web of knowledge databases were considered for this study. We included cross-sectional, cohort, and case-control studies that have reported NiV CFR and/or risk factors. Data were pooled with random-effects model. This review was registered in the PROSPERO, CRD42018116242. FINDINGS: This global review included 22 citations (25 studies) including 2156, 1682, and 474 suspected, probable, and confirmed cases of NiV encephalitis, respectively. We determined a pooled CFR for NiV encephalitis at 61.0% (95% CI, 45.7-75.4; I² = 96.8%). Climbing trees (OR = 1.4; 95% CI; 1.0-1.9), male gender (OR = 1.5; 95% CI; 1.1-2.0), travel outside their own sub-district (OR = 2.0; 95% CI; 1.4-2.9), and exposure to date palm sap (DPS) (OR = 5.7; 95% CI; 3.8-8.6) or pigs (OR = 7.6; 95% CI; 1.2-45.4) were significantly associated with NiV infection. CONCLUSION: Findings from this study suggest that NiV Encephalitis is associated with a high CFR and that male gender, travel outside their sub-district, climbing trees, and exposure to pigs and DPS are associated with an increased risk of NiV encephalitis.
Subject(s)
Encephalitis, Viral/mortality , Henipavirus Infections/mortality , Nipah Virus/pathogenicity , Animals , Female , Humans , Male , Mortality , Risk Factors , Sex Characteristics , Zoonoses/epidemiology , Zoonoses/mortalityABSTRACT
Following the discovery in 2015 of the variegated squirrel bornavirus 1 (VSBV-1) in fatal encephalitis cases among exotic squirrel breeders and a zoo animal caretaker in Germany, a case definition was developed. It was employed during trace-back animal trade investigations and sero-epidemiological studies among breeders and zoo animal caretakers of holdings with VSBV-1 infected squirrels. During the investigation, two possible human cases who had died of encephalitis were identified retrospectively among the squirrel breeders. Moreover, one probable human case was detected among the breeders who had a positive memory T-cell response to VSBV-1 antigen and antibodies against VSBV-1. The low rate of seropositivity found among living persons in risk groups that handle exotic squirrels privately or at zoos may reflect rareness of exposure to VSBV-1 during animal contact, a high lethality of infection or a combination of these factors. As a precaution against human exposure, testing of exotic squirrels for VSBV-1 infection and/or avoiding direct contact with exotic squirrels in zoos and private holdings is strongly advised.
Subject(s)
Bornaviridae/genetics , Encephalitis, Viral/diagnosis , Encephalitis, Viral/virology , Mononegavirales Infections/virology , Occupational Exposure/adverse effects , Sciuridae/virology , Zoonoses , Animals , Bornaviridae/classification , Bornaviridae/isolation & purification , Communicable Diseases, Emerging , Encephalitis, Viral/mortality , Encephalitis, Viral/pathology , Flow Cytometry , Germany/epidemiology , Humans , Mononegavirales Infections/pathology , Mononegavirales Infections/transmission , Phylogeny , Public Health Surveillance , RNA, Viral , Sequence Analysis, DNA , Serologic Tests , Zoonoses/transmission , Zoonoses/virologyABSTRACT
BACKGROUND: Eastern equine encephalitis virus is an alphavirus that naturally cycles between mosquitoes and birds or rodents in Eastern States of the US. Equine infection occurs by being bitten by cross-feeding mosquitoes, with a case fatality rate of up to 75% in humans during epizootic outbreaks. There are no licensed medical countermeasures, and with an anticipated increase in mortality when exposed by the aerosol route based on anecdotal human data and experimental animal data, it is important to understand the pathogenesis of this disease in pursuit of treatment options. This report details the clinical and pathological findings of mice infected with EEEV by the aerosol route, and use as a model for EEEV infection in humans. METHODS: Mice were exposed by the aerosol route to a dose range of EEEV to establish the median lethal dose. A pathogenesis study followed whereby mice were exposed to a defined dose of virus and sacrificed at time-points thereafter for histopathological analysis and virology. RESULTS: Clinical signs of disease appeared within 2 days post challenge, culminating in severe clinical signs within 24 h, neuro-invasion and dose dependent lethality. EEEV was first detected in the lung 1 day post challenge, and by day 3 peak viral titres were observed in the brain, spleen and blood, corresponding with severe meningoencephalitis, indicative of encephalitic disease. Lethality follows severe neurological signs, and may be linked to a threshold level of virus replication in the brain. Effective medical countermeasures for EEEV may necessitate early inoculation to inhibit infection of the brain in zoonotic incidents, and be able to traverse the blood-brain barrier to sufficiently interrupt replication in the brain in cases of aerosol infection. CONCLUSIONS: There is little human data on the hazard posed by aerosol infection with encephalitic alphaviruses, and use of EEEV as a bioweapon may be by the aerosol route. A well characterized model of aerosol exposure that recapitulates some of the most severe human clinical features is necessary to evaluate the efficacy of putative medical countermeasures, and to increase our understanding about how this route of infection induces such rapid neuro-invasion and resulting disease.
Subject(s)
Disease Susceptibility/virology , Encephalitis Virus, Eastern Equine/pathogenicity , Encephalitis, Viral/pathology , Aerosols , Animals , Brain/virology , Disease Models, Animal , Encephalitis, Viral/mortality , Female , Lung/virology , Mice , Mice, Inbred BALB C , Virus ReplicationSubject(s)
Chiroptera/virology , Disease Outbreaks , Encephalitis, Viral/epidemiology , Henipavirus Infections/epidemiology , Nipah Virus/physiology , Swine Diseases/epidemiology , Animals , Disease Reservoirs/virology , Encephalitis, Viral/mortality , Encephalitis, Viral/transmission , Encephalitis, Viral/virology , Henipavirus Infections/mortality , Henipavirus Infections/transmission , Henipavirus Infections/virology , Humans , India/epidemiology , Nipah Virus/genetics , Phoeniceae/virology , RNA, Viral/analysis , Swine , Swine Diseases/transmission , Swine Diseases/virology , ZoonosesABSTRACT
BACKGROUND: Due to the increasing number of DCD transplantations since 2015, the transmission of rabies through solid organ transplantation has become a notable problem in China and has attracted the attention of the public. CASE PRESENTATION: From 2015 to 2017, four solid organ recipients in our centre were successively diagnosed with rabies that was considered to have been transmitted from two donors who died due to viral encephalitis of unknown cause and acute disseminated encephalomyelitis. The incubation periods were 44, 48, 158 and 303 days. The four patients had neurological symptoms associated with rabies and died. The survival times were 44, 34, 8 and 6 days. Another kidney transplant recipient received timely post-exposure prophylaxis and has remained asymptomatic. CONCLUSIONS: Organs should be discarded whenever rabies is confirmed or suspected, especially in cases diagnosed as encephalitis of unknown cause. It is important to establish a supervisory system to manage donor-derived infectious diseases. When rabies-infected donor organs are inadvertently transplanted, the recipients must receive post-exposure prophylaxis in a timely manner, which may be the only possible effective method to prevent the transmission of rabies.
Subject(s)
Encephalitis, Viral/diagnosis , Organ Transplantation , Rabies/diagnosis , Adult , Child , Encephalitis, Viral/etiology , Encephalitis, Viral/mortality , Female , Humans , Kidney Transplantation , Male , Middle Aged , Post-Exposure Prophylaxis , RNA, Viral/urine , Rabies/mortality , Rabies/transmission , Rabies virus/genetics , Rabies virus/isolation & purification , Saliva/virology , Sputum/virology , Tissue DonorsABSTRACT
The importance of TLR2 and TLR9 in the recognition of infection with herpes simplex virus (HSV) and HSV-caused diseases has been described, but some discrepancies remain concerning the benefits of these responses. Moreover, the impact of TLR2/9 on innate and adaptive immune responses within relevant mucosal tissues has not been elucidated using natural mucosal infection model of HSV. Here, we demonstrate that dual TLR2/9 recognition is essential to provide resistance against mucosal infection with HSV via an intravaginal route. Dual TLR2/9 ablation resulted in the highly enhanced mortality with exacerbated symptoms of encephalitis compared with TLR2 or TLR9 deficiency alone, coinciding with highly increased viral load in central nervous system tissues. TLR2 appeared to play a minor role in providing resistance against mucosal infection with HSV, since TLR2-ablated mice showed higher survival rate compared with TLR9-ablated mice. Also, the high mortality in dual TLR2/9-ablated mice was closely associated with the reduction in early monocyte and NK cell infiltration in the vaginal tract (VT), which was likely to correlate with low expression of cytokines and CCR2 ligands (CCL2 and CCL7). More interestingly, our data revealed that dual TLR2/9 recognition of HSV infection plays an important role in the functional maturation of TNF-α and iNOS-producing dendritic cells (Tip-DCs) from monocytes as well as NK cell activation in VT. TLR2/9-dependent maturation of Tip-DCs from monocytes appeared to specifically present cognate Ag, which effectively provided functional effector CD4+ and CD8+ T cells specific for HSV Ag in VT and its draining lymph nodes. TLR2/9 expressed in monocytes was likely to directly facilitate Tip-DC-like features after HSV infection. Also, dual TLR2/9 recognition of HSV infection directly activated NK cells without the aid of dendritic cells through activation of p38 MAPK pathway. Taken together, these results indicate that dual TLR2/9 recognition plays a critical role in providing resistance against mucosal infection with HSV, which may involve a direct regulation of Tip-DCs and NK cells in VT. Therefore, our data provide a more detailed understanding of TLR2/9 role in conferring antiviral immunity within relevant mucosal tissues after mucosal infection with HSV.
Subject(s)
Central Nervous System/virology , Herpes Simplex/immunology , Killer Cells, Natural/immunology , Lymphocyte Activation , Monocytes/immunology , Toll-Like Receptor 2/immunology , Toll-Like Receptor 9/immunology , Animals , Central Nervous System/immunology , Cytokines/genetics , Dendritic Cells/immunology , Encephalitis, Viral/mortality , Female , Immunity, Innate , Immunity, Mucosal , Mice , Mice, Inbred BALB C , Mice, Knockout , Toll-Like Receptor 2/genetics , Toll-Like Receptor 9/genetics , Vagina/immunology , Vagina/virology , Viral LoadABSTRACT
BACKGROUND: Data to guide neurointensivists seeing patients with West Nile Neuroinvasive disease (WNND) are lacking. We present a comparatively large series of patients with WNND admitted to the intensive care unit (ICU) and provide data on their early diagnosis, triage to the ICU and predictors of short-term outcomes. METHODS: We retrospectively identified patients aged ≥ 18 years old with WNND from January 1999 to November 2016. Demographic and clinical data, the modified Rankin Scale at discharge and disposition were collected. Univariate analysis was performed to find predictors of ICU admission and to assess the impact of ICU admission on the short-term outcomes. P values < 0.05 were considered significant. RESULTS: Among 26 patients, 16 were admitted to the ICU. Age < 60 years and the presentation with encephalitis and acute flaccid paralysis predicted ICU admission (P = 0.044 and 0.0007). Among patients requiring ICU admission, four died and no one was discharged home. ICU admission predicted longer hospital stay (P = 0.021), inhospital death (P = 0.034), survival with inability to walk independently (P = 0.0094), and discharge disposition other than home (P = 0.007). In the ICU group, older age was associated with longer hospital stay (P = 0.0001) and inhospital death (P = 0.035). CONCLUSION: WNND requiring ICU care has a high morbidity and mortality, especially among older patients. Survivors are highly disabled at discharge, but many improve over time. Therefore, more data on the long-term prognosis of survivors are needed to guide the goals of care in the acute setting.
Subject(s)
Encephalitis, Viral , Intensive Care Units/statistics & numerical data , Meningitis, Viral , Outcome Assessment, Health Care/statistics & numerical data , Paralysis , West Nile Fever , Adult , Aged , Critical Illness , Encephalitis, Viral/diagnosis , Encephalitis, Viral/etiology , Encephalitis, Viral/mortality , Encephalitis, Viral/therapy , Female , Humans , Male , Meningitis, Viral/diagnosis , Meningitis, Viral/etiology , Meningitis, Viral/mortality , Meningitis, Viral/therapy , Middle Aged , Paralysis/diagnosis , Paralysis/etiology , Paralysis/mortality , Paralysis/therapy , Retrospective Studies , West Nile Fever/complications , West Nile Fever/diagnosis , West Nile Fever/mortality , West Nile Fever/therapyABSTRACT
BACKGROUND: Viral encephalitis is a dangerous compromise between the need to robustly clear pathogen from the brain and the need to protect neurons from bystander injury. Theiler's murine encephalomyelitis virus (TMEV) infection of C57Bl/6 mice is a model of viral encephalitis in which the compromise results in hippocampal damage and permanent neurological sequelae. We previously identified brain-infiltrating inflammatory monocytes as the primary driver of this hippocampal pathology, but the mechanisms involved in recruiting these cells to the brain were unclear. METHODS: Chemokine expression levels in the hippocampus were assessed by microarray, ELISA, RT-PCR, and immunofluorescence. Monocyte infiltration during acute TMEV infection was measured by flow cytometry. CCL2 levels were manipulated by immunodepletion and by specific removal from neurons in mice generated by crossing a line expressing the Cre recombinase behind the synapsin promoter to animals with floxed CCL2. RESULTS: Inoculation of the brain with TMEV induced hippocampal production of the proinflammatory chemokine CCL2 that peaked at 6 h postinfection, whereas inoculation with UV-inactivated TMEV did not elicit this response. Immunofluorescence revealed that hippocampal neurons expressed high levels of CCL2 at this timepoint. Genetic deletion of CCR2 and systemic immunodepletion of CCL2 abrogated or blunted the infiltration of inflammatory monocytes into the brain during acute infection. Specific genetic deletion of CCL2 from neurons reduced serum and hippocampal CCL2 levels and inhibited inflammatory monocyte infiltration into the brain. CONCLUSIONS: We conclude that intracranial inoculation with infectious TMEV rapidly induces the expression of CCL2 in neurons, and this cellular source is necessary for CCR2-dependent infiltration of inflammatory monocytes into the brain during the most acute stage of encephalitis. These findings highlight a unique role for neuronal production of chemokines in the initiation of leukocytic infiltration into the infected central nervous system.
Subject(s)
Chemokine CCL2/biosynthesis , Encephalitis, Viral/mortality , Hippocampus/pathology , Monocytes/immunology , Neurons/metabolism , Animals , Cardiovirus Infections/immunology , Cardiovirus Infections/metabolism , Cardiovirus Infections/pathology , Chemotaxis, Leukocyte/immunology , Encephalitis, Viral/immunology , Encephalitis, Viral/metabolism , Encephalitis, Viral/pathology , Hippocampus/immunology , Hippocampus/virology , Mice , Mice, Inbred C57BL , TheilovirusABSTRACT
In this retrospective analysis using the Transplant Registry Unified Management Program, we identified 145 patients with human herpesvirus (HHV)-6 encephalitis among 6593 recipients. The cumulative incidences of HHV-6 encephalitis at 100 days after transplantation in all patients, recipients of bone marrow or PBSCs and recipients of cord blood were 2.3%, 1.6% and 5.0%, respectively. Risk factors identified in multivariate analysis were male sex, type of transplanted cells (relative risk in cord blood transplantation, 11.09, P<0.001; relative risk in transplantation from HLA-mismatched unrelated donor, 9.48, P<0.001; vs transplantation from HLA-matched related donor) and GvHD prophylaxis by calcineurin inhibitor alone. At 100 days after transplantation, the overall survival rate was 58.3% and 80.5% among patients with and without HHV-6 encephalitis, respectively (P<0.001). Neuropsychological sequelae remained in 57% of 121 evaluated patients. With both foscarnet and ganciclovir, full-dose therapy (foscarnet ⩾180 mg/kg, ganciclovir ⩾10 mg/kg) was associated with better response rate (foscarnet, 93% vs 74%, P=0.044; ganciclovir, 84% vs 58%, P=0.047). HHV-6 encephalitis is not rare not only in cord blood transplant recipients but also in recipients of HLA-mismatched unrelated donors. In this study, development of HHV-6 encephalitis was associated with a poor survival rate, and neurological sequelae remained in many patients.
Subject(s)
Encephalitis, Viral/therapy , Herpesvirus 6, Human/pathogenicity , Stem Cell Transplantation/methods , Adolescent , Antiviral Agents/therapeutic use , Encephalitis, Viral/mortality , Encephalitis, Viral/virology , Foscarnet/therapeutic use , Ganciclovir/therapeutic use , Humans , Registries , Retrospective Studies , Risk Factors , Roseolovirus Infections , Stem Cell Transplantation/adverse effects , Survival Analysis , Tissue Donors , Transplantation, Homologous/adverse effectsABSTRACT
Braak and Del Tredici have proposed that typical Parkinson disease (PD) has its origins in the olfactory bulb and gastrointestinal tract. However, the role of the olfactory system has insufficiently been explored in the pathogeneses of PD and Alzheimer disease (AD) in laboratory models. Here, we demonstrate applications of a new method to process mouse heads for microscopy by sectioning, mounting, and staining whole skulls ('holocranohistochemistry'). This technique permits the visualization of the olfactory system from the nasal cavity to mitral cells and dopamine-producing interneurons of glomeruli in the olfactory bulb. We applied this method to two specific goals: first, to visualize PD- and AD-linked gene expression in the olfactory system, where we detected abundant, endogenous α-synuclein and tau expression in the olfactory epithelium. Furthermore, we observed amyloid-ß plaques and proteinase-K-resistant α-synuclein species, respectively, in cranial nerve-I of APP- and human SNCA-over-expressing mice. The second application of the technique was to the modeling of gene-environment interactions in the nasal cavity of mice. We tracked the infection of a neurotropic respiratory-enteric-orphan virus from the nose pad into cranial nerves-I (and -V) and monitored the ensuing brain infection. Given its abundance in the olfactory epithelia, we questioned whether α-synuclein played a role in innate host defenses to modify the outcome of infections. Indeed, Snca-null mice were more likely to succumb to viral encephalitis versus their wild-type littermates. Moreover, using a bacterial sepsis model, Snca-null mice were less able to control infection after intravenous inoculation with Salmonella typhimurium. Together, holocranohistochemistry enabled new discoveries related to α-synuclein expression and its function in mice. Future studies will address: the role of Mapt and mutant SNCA alleles in infection paradigms; the contribution of xenobiotics in the initiation of idiopathic PD; and the safety to the host when systemically targeting α-synuclein by immunotherapy.
Subject(s)
Brain/metabolism , Brain/virology , Encephalitis, Viral/virology , Olfactory Mucosa/anatomy & histology , Olfactory Mucosa/metabolism , Reoviridae Infections/virology , alpha-Synuclein/metabolism , Amyloid beta-Protein Precursor/genetics , Amyloid beta-Protein Precursor/metabolism , Animals , Brain/diagnostic imaging , Brain/pathology , Disease Models, Animal , Encephalitis, Viral/immunology , Encephalitis, Viral/mortality , Encephalitis, Viral/pathology , Female , Head , Humans , Immunohistochemistry , Male , Mammalian orthoreovirus 3 , Mice , Mice, 129 Strain , Mice, Inbred C57BL , Mice, Transgenic , Neural Pathways/anatomy & histology , Neural Pathways/diagnostic imaging , Neural Pathways/metabolism , Neural Pathways/pathology , Olfactory Mucosa/pathology , Olfactory Receptor Neurons/metabolism , Olfactory Receptor Neurons/virology , Reoviridae Infections/immunology , Salmonella Infections/immunology , Salmonella Infections/pathology , Salmonella typhimurium , Tissue Preservation/methods , alpha-Synuclein/geneticsABSTRACT
BACKGROUND: Enterovirus 71 (EV-A71) shows a potential of rapid death, but the natural history of the infection is poorly known. This study aimed to examine the natural history of EV-A71 infection. METHODS: This was a prospective longitudinal observational study performed between January 1st and October 31st, 2012, at three hospitals in Guangdong, China. Subjects with positive EV-A71 RNA laboratory test results were included. Disease progression was documented with MRI, autopsies, and follow-up. Symptoms/signs with potential association with risk of death were analyzed. RESULTS: Among the 288 patients, neurologic symptoms and signs were observed (emotional movement disorders, dyskinesia, involuntary movements, autonomic dysfunction, and disturbance of consciousness). Some of them occurred as initial symptoms. Myoclonic jerks/tremors were observed among >50% of the patients; nearly 40% of patients presented fatigue and 25% were with vomiting. Twenty-eight patients (9.7%) presented poor peripheral perfusion within 53.4 ± 26.1 h; 23 patients (8.0%) presented pulmonary edema and/or hemorrhage within 62.9 ± 28.6 h. Seventeen (5.9%) patients were in a coma. Seven (2.4%) patients died within 62.9 ± 28.6 h. Seventy-seven survivors underwent head and spinal cord MRI and 37.7% (29/77) showed abnormalities. Two fatal cases showed neuronal necrosis, softening, perivascular cuffing, colloid, and neuronophagia phenomenon in the brainstem. CONCLUSIONS: Patients with EV-A71 infection showed high complexity of symptoms and onset timing. Death risk may be indicated by autokinetic eyeball, eyeball ataxia, severe coma, respiratory rhythm abnormality, absent pharyngeal reflex, ultrahyperpyrexia, excessive tachycardia, pulmonary edema and/or hemorrhage, and refractory shock and ataxic respiration. Early assessment of these symptoms/signs is important for proper management.
Subject(s)
Encephalitis, Viral/diagnosis , Enterovirus A, Human/pathogenicity , Enterovirus Infections/diagnosis , Enterovirus Infections/virology , Hemorrhage/diagnosis , Pulmonary Edema/diagnosis , Respiration Disorders/diagnosis , Autopsy , Child , Child, Preschool , China/epidemiology , Coma , Disease Outbreaks , Disease Progression , Encephalitis, Viral/mortality , Encephalitis, Viral/physiopathology , Enterovirus A, Human/isolation & purification , Enterovirus Infections/mortality , Enterovirus Infections/physiopathology , Female , Hemorrhage/mortality , Hemorrhage/physiopathology , Humans , Infant , Longitudinal Studies , Magnetic Resonance Imaging , Male , Prospective Studies , Pulmonary Edema/mortality , Pulmonary Edema/physiopathology , Respiration Disorders/mortality , Respiration Disorders/physiopathology , Respiratory Rate/physiologyABSTRACT
In Georgia, causative agents among infants with systemic infections are generally not identified and "neonatal sepsis" is usually diagnosed and treated without determining the etiology. The objective of this study was to estimate the role of viral pathogens (Herpesviridae and Enteroviruses) among neonates with generalized infections. A cross-sectional study was performed among neonates younger than <8 weeks admitted to a neonatal intensive care unit (NICU) at the two largest pediatric hospitals in Tbilisi, Georgia. Laboratory tests were performed by consensus and then by type-specific PCR methods. A total of 187 infants were recruited from the NICUs; most participants (74.9%) were of normal birth weight at admission to the NICU and half (51.3%) were younger than 7 days of age. Almost all babies (91.4%) were treated with a broad-spectrum antibiotic despite a lack of microbe identification. While the overall mortality rate of infants with a systemic infection was 21.9 %, neonatal outcomes were more favorable when the infection was due to enteroviruses (2.9% mortality rate) compared to a herpesvirus infection (16.1% mortality rate). Multivariate analyses identified independent predictors associated with neonatal mortality. These included etiology of infection, APGAR score and the type of delivery. Our investigation suggests that viral pathogens play a substantial role in systemic infections among NICU infants. Utilizing molecular-based testing in these cases could improve both the clinical management and outcomes of neonates with generalized infections.