Neural Injury and Repair in a Novel Neonatal Mouse Model of Listeria Monocytogenes Meningoencephalitis.

To improve the therapy of neonatal central nervous system infections, well-characterized animal models are urgently needed. The present study analyzes neuropathological alterations with particular focus on neural injury and repair in brains of neonatal mice with Listeria monocytogenes (LM) meningitis/meningoencephalitis using a novel nasal infection model. The hippocampal formation and frontal cortex of 14 neonatal mice with LM meningitis/meningoencephalitis and 14 uninfected controls were analyzed by histology, immunohistochemistry, and in situ tailing for morphological alterations. In the dentate gyrus of the hippocampal formation of mice with LM meningitis/meningoencephalitis, an increased density of apoptotic neurons visualized by in situ tailing (p = 0.04) and in situ tailing plus immunohistochemistry for activated Caspase-3 (p < 0.0001) was found. A decreased density of dividing cells stained with an anti-PCNA-antibody (p < 0.0001) and less neurogenesis visualized by anti-calretinin (p < 0.0001) and anti-calbindin (p = 0.01) antibodies were detected compared to uninfected controls. The density of microglia was higher in LM meningitis (p < 0.0001), while the density of astrocytes remained unchanged. Infiltrating monocytes and neutrophilic granulocytes likely contributed to tissue damage. In conclusion, in the brains of LM-infected mice a strong immune response was observed which led to neuronal apoptosis and an impaired neural regeneration. This model appears very suitable to study therapies against long-term sequelae of neonatal LM meningitis.

Meningoencephalitis in relapsing polychondritis: A case report.

RATIONALE: Aseptic meningoencephalitis is a rare central nervous system complication of relapsing polychondritis (RP). PATIENT: We report a 61-year-old Japanese male patient with spiking fever and impaired consciousness. Neurological examination revealed meningealirritation, and cerebrospinal fluid (CSF) examination showed lymphocytic pleocytosis with elevated protein (199 mg/dL) and interleukin-6 (3810 pg/mL). Serological analysis showed high levels of anti-type II collagen antibodies, and the result of auricular biopsy was consistent with the diagnosis of RP showing cartilage degeneration surrounded by inflammatory cell infiltrations. DIAGNOSIS: A clinical diagnosis of RP was made according to the diagnostic criteria established by MacAdams et al. INTERVENTION: Steroid pulse therapy (methylprednisolone 1000 mg, consecutive 3 days) followed by oral prednisolone (60 mg/day) resolved the patient's high fever and disturbance of consciousness. OUTCOMES: The patient rapidly improved after steroid treatments and has a normal quality of life under the maintenance dose of steroid plus methotrexate (4 mg/week). LESSONS: RP-associated meningoencephalitis is a rare complication with significant morbidity and mortality. It should be considered and differentiated in patients with RP with unexplained spiking fever and impaired consciousness. In addition, the assessment of cerebrospinal fluid interleukin-6 levels may be useful to investigate the disease activity of RP-related meningoencephalitis. Further prospective studies are required to confirm this result.

Plasmapheresis treatment in COVID-19-related autoimmune meningoencephalitis: Case series.

Severe SARS-CoV-2 (COVID-19) infection has the potential for a high mortality rate. In this paper, we report the results of plasmapheresis treatment in a series of severely ill patients with COVID-19-related autoimmune meningoencephalitis in the Intensive Care Unit (ICU).

A 9-month retrospective evaluation of the aetiology and management of patients presenting with encephalitis/meningoencephalitis at a South London hospital.

Encephalitis causes high morbidity and mortality. An incidence of 4.3 cases of encephalitis/100 000 population has been reported in the UK. We performed a retrospective evaluation of the diagnosis and management of adults admitted to hospital with a clinical diagnosis of encephalitis/meningoencephalitis. Clinical, laboratory and radiological data were collated from electronic records. Thirty-six patients, median age 55 years and 24 (67%) male were included. The aetiology was confirmed over nine months in 25 (69%) of whom 16 were infections (six viral, seven bacterial, two parasitic and one viral and parasitic co-infection); 7 autoimmune; 1 metabolic and 1 neoplastic. Of 24 patients with fever, 15 (63%) had an infection. The median time to computed topography, magnetic resonance imaging and electroencephalography (EEG) was 1, 8 and 3 days respectively. Neuroimaging was abnormal in 25 (69%) and 17 (89%) had abnormal EEGs. Only 19 (53%) received aciclovir treatment. Six (17%) made good recoveries, 16 (44%) had moderate disability, 8 (22%) severe disability and 6 (17%) died. Outcomes were worse for those with an infectious cause. In summary, a diagnosis was made in 69.4% of patients admitted with encephalitis/meningoencephalitis. Autoimmune causes are important to consider at an early stage due to a successful response to treatment. Only 53% of patients received aciclovir on admission. Neuroimaging and EEG studies were delayed. The results of this work resulted in further developing the clinical algorithm for managing these patients.

Presence of cerebrospinal fluid antibodies associated with autoimmune encephalitis of humans in dogs with neurologic disease.

BACKGROUND: Presumed autoimmune diseases affecting the central nervous system (CNS) of dogs are common. In people, antibodies against neuronal cell surface antigens that are associated with a wide variety of neurological syndromes have been identified. The presence of cerebrospinal fluid (CSF) autoantibodies that target neuronal cell surface proteins has not been reported in dogs with neurologic disorders. OBJECTIVES: Autoantibodies to neuronal cell surface antigens can be found in the CSF of dogs with inflammatory CNS disease. Our aim was to determine whether 6 neuronal cell surface autoantibodies were present in the CSF of dogs diagnosed with inflammatory and noninflammatory CNS disease. ANIMALS: Client-owned dogs with CNS disease and complete diagnostic evaluation including magnetic resonance imaging and CSF analysis were included. One healthy dog was included as a negative control. METHODS: Cerebrospinal fluid was tested for 6 antigenic targets with a commercially available indirect immunofluorescence assay test kit. RESULTS: There were 32 dogs with neurological disease, 19 diagnosed with inflammatory disease (encephalitis and meningitis), 10 with noninflammatory disease (neoplasia, intervertebral disk disease, degenerative myelopathy, and epilepsy), 2 with no diagnosis, and 1 with neoplasia and meningoencephalitis. Anti-N-methyl-d-aspartate receptor 1 (NMDAR1) antibodies were detected in 3 dogs (3/32; 9.38%). All 3 dogs responded to treatment of meningoencephalomyelitis of unknown etiology (MUE). CONCLUSIONS AND CLINICAL IMPORTANCE: Further evaluation of the prevalence and clinical relevance of CSF and serum antibodies to neuronal cell surface antigens is warranted. Defining antigenic targets associated with encephalitis in dogs might allow diagnostic categorization of MUE antemortem.

Successful treatment of post-transplant CMV meningoencephalitis with third-party CMV virus-specific T cells: Lessons learned.

Cytomegalovirus encephalitis is a challenging life-threatening complication following hematopoietic stem cell transplantation for which medical treatment is usually ineffective or toxic. However, in recent years, adoptive T-cell therapy has been reported to provide a significant chance of cure for patients with viral infections. Herein, two cases of pediatric patients successfully treated with third-party donor-derived virus-specific T cells for CMV meningoencephalitis are reported.

Lymphocytic choriomeningitis virus meningoencephalitis in a renal transplant recipient following exposure to mice.

Solid organ transplant recipients (SOTR) are at increased risk for a wide variety of typical and atypical infections as a consequence of impaired cell mediated and humoral immunity. We report a case of meningoencephalitis in a renal transplant recipient caused by lymphocytic choriomeningitis virus (LCMV) acquired by exposure to mice excreta. The clinical course was complicated by the development of hydrocephalus, requiring a ventriculoperitoneal shunt. To our knowledge, this is the first reported case of LCMV infection in a SOTR that was not organ donor derived.

Hypertrophic pachymeningoencephalitis associated with temporal giant cell arteritis.

We report the rare case of an 80-year-old male patient with hypertrophic pachymeningoencephalitis that may be associated with temporal arteritis. The patient presented to our neurological department with a 2-week history of latent paresis and ataxia affecting his right hand. He had been diagnosed with temporal arteritis 12 years earlier. Brain MRI showed an enhancement of the left-sided frontoparietal meninges with oedema of the adjacent tissue of the precentral and postcentral cortex. A leptomeningeal biopsy was performed. An autoimmune-mediated immunoglobulin G4-associated hypertrophic pachymeningoencephalitis was diagnosed. The patient received a high-dose corticosteroid therapy and his symptoms gradually improved. Our results suggest that hypertrophic pachymeningoencephalitis may occur as a complication of giant cell arteritis and may cause central neurological deficits by cerebral perifocal oedema.

Glial fibrillary acidic protein antibody-positive meningoencephalomyelitis.

Glial fibrillary acidic protein antibody-positive meningoencephalomyelitis is a newly described, possibly under-recognised, severe inflammatory condition of the nervous system. The clinical presentation is variable but most commonly is a combination of meningitis, encephalitis and myelitis; other manifestations may include seizures, psychiatric symptoms and tremor. There is a significant association with malignancies, often occult, and with other autoimmune conditions. Although the disease responds well to corticosteroids acutely, it typically relapses when these are tapered, and so patients need long-term immunosuppression. We report a young man presenting with subacute meningoencephalitis and subsequent myelitis, and discuss the typical presentation and management of this severe but treatable condition.

Post-traumatic stress after PICU and corticosteroid use.

AIM: To examine the association between corticosteroid use in paediatric intensive care units (PICU) and subsequent symptoms of post-traumatic stress disorder (PTSD). METHODS: The subjects were children aged 8-16 years admitted to PICU with sepsis, meningoencephalitis (ME) and other disorders. Illness information was extracted from case notes; 3-6 months post discharge children completed a PTSD symptom questionnaire (eight-item Impact of Events Scale (IES-8)) assessing intrusion and avoidance symptoms. Saliva samples were also collected for cortisol profile analysis. RESULTS: 53 children completed the IES-8 questionnaires. 33 provided saliva samples. 19 (36%) received corticosteroids. In children with sepsis (n=15), corticosteroid use was associated with significantly lower PTSD intrusion symptom scores. There was a trend towards an association between corticosteroid use and lower evening cortisol levels. There was a comparable but weaker trend in children with ME. DISCUSSION: Corticosteroid use may be associated with fewer PTSD symptoms and lower evening cortisol levels following PICU admission in children with sepsis.

Clinical and immunological characteristics of the spectrum of GFAP autoimmunity: a case series of 22 patients.

OBJECTIVE: To report the clinical and immunological characteristics of 22 new patients with glial fibrillar acidic protein (GFAP) autoantibodies. METHODS: From January 2012 to March 2017, we recruited 451 patients with suspected neurological autoimmune disease at the Catholic University of Rome. Patients' serum and cerebrospinal fluid (CSF) samples were tested for neural autoantibodies by immunohistochemistry on mouse and rat brain sections, by cell-based assays (CBA) and immunoblot. GFAP autoantibodies were detected by immunohistochemistry and their specificity confirmed by CBA using cells expressing human GFAPα and GFAPδ proteins, by immunoblot and immunohistochemistry on GFAP-/- mouse brain sections. RESULTS: Serum and/or CSF IgG of 22/451 (5%) patients bound to human GFAP, of which 22/22 bound to GFAPα, 14/22 to both GFAPα and GFAPδ and none to the GFAPδ isoform only. The neurological presentation was: meningoencephalomyelitis or encephalitis in 10, movement disorder (choreoathetosis or myoclonus) in 3, anti-epileptic drugs (AED)-resistant epilepsy in 3, cerebellar ataxia in 3, myelitis in 2, optic neuritis in 1 patient. Coexisting neural autoantibodies were detected in five patients. Six patients had other autoimmune diseases. Tumours were found in 3/22 patients (breast carcinoma, 1; ovarian carcinoma, 1; thymoma, 1). Nineteen patients were treated with immunotherapy and 16 patients (84%) improved. Histopathology analysis of the leptomeningeal biopsy specimen from one patient revealed a mononuclear infiltrate with macrophages and CD8+ T cells. CONCLUSIONS: GFAP autoimmunity is not rare. The clinical spectrum encompasses meningoencephalitis, myelitis, movement disorders, epilepsy and cerebellar ataxia. Coexisting neurological and systemic autoimmunity are relatively common. Immunotherapy is beneficial in most cases.

Subclinical meningoventriculitis as a cause of obstructive hydrocephalus.

Communicating hydrocephalus may complicate infantile bacterial meningitis, typically presenting with systemic features of infection. We report a rare case of 'subclinical meningoventriculitis' causing obstructive hydrocephalus and its challenging management. A healthy 10-week-old immunocompetent male patient presented with failure to thrive and vomiting, secondary to presumed gastro-oesophageal reflux. The child was neurologically alert, afebrile with normal inflammatory markers. Progressive macrocephaly prompted an MRI confirming triventricular hydrocephalus secondary to aqueductal stenosis. An endoscopic third ventriculostomy was performed however abandoned intraoperatively due to the unexpected finding of intraventricular purulent cerebrospinal fluid. A 6-week course of intravenous ceftriaxone was commenced for Escherichia coli meningoventriculitis. However, the child was readmitted 18 days postoperatively with acute hydrocephalus requiring a ventricular washout and staged ventriculoperitoneal shunt insertion at 4 weeks. Serial head circumference measurements are paramount in the assessment of a paediatric patient. In an immunocompetent child, a subclinical fibropurulent meningoventriculitis can result in several management challenges.