Clinical management of infectious cerebral vasculitides

Harnessing the Potential of Exosomes in Therapeutic Interventions for Brain Disorders

Exosomes, which are nano-sized natural vesicles secreted by cells, are crucial for intercellular communication and interactions, playing a significant role in various physiological and pathological processes. Their characteristics, such as low toxicity and immunogenicity, high biocompatibility, and remarkable drug delivery capabilities-particularly their capacity to traverse the blood-brain barrier-make exosomes highly promising vehicles for drug administration in the treatment of brain disorders. This review provides a comprehensive overview of exosome biogenesis and isolation techniques, strategies for the drug loading and functionalization of exosomes, and exosome-mediated blood-brain barrier penetration mechanisms, with a particular emphasis on recent advances in exosome-based drug delivery for brain disorders. Finally, we address the opportunities and challenges associated with utilizing exosomes as a drug delivery system for the brain, summarizing the barriers to clinical translation and proposing future research directions.

Clinical and laboratory characteristics of neurosyphilis: analysis of symptoms and risk factors

BACKGROUND

The present study was conducted from 2021 to 2023 to analyze the clinical and laboratory characteristics of neurosyphilis and determine the risk factors associated with this condition.

METHODS

A total of 400 patients were enrolled, including 100 individuals diagnosed with neurosyphilis, 100 without neurosyphilis, 100 with latent syphilis, and 100 healthy control subjects. Comparative analysis methods, serum VDRL titration, and correlation analysis were employed during the study.

RESULTS

The analysis revealed significant differences in symptoms of central nervous system (CNS) involvement and serum VDRL titers among the patient groups. For instance, symptoms indicative of CNS impairment were more frequently observed in patients with neurosyphilis, and serum VDRL titers were statistically significantly higher in this same group.

CONCLUSIONS

The obtained results can be utilized in clinical practice to enhance the accuracy of neurosyphilis diagnosis and management, thereby contributing to the improvement of early detection of this condition and prevention of its complications. The study allows for the inference of the importance of early detection of (CNS) dysfunction symptoms in patients (neurosyphilis) with syphilis and identifies key factors influencing the development of this disease. The findings hold significance for the diagnosis and treatment of neurosyphilis.

Percutaneous Cerebral Angioplasty for Refractory Middle Cerebral Artery Stenosis Due to Varicella-Zoster Virus-Related Vasculopathy: A Case Report

An 81-year-old man was admitted to our hospital with left hemiplegia after treatment for herpes zoster of the first branch of the right trigeminal nerve. CSF examination revealed an elevated varicella-zoster virus (VZV) antibody index. Brain MRI showed cerebral infarction in the right middle cerebral artery (MCA) territory and vessel wall thickening and enhancing effects at the ipsilateral MCA. Despite the standard treatment, the MCA stenosis progressed with recurrent infarcts. Percutaneous cerebral angioplasty was performed to the distal portion of the right MCA without deterioration. This case can provide a treatment option for refractory progressive VZV vasculopathy.

Varicella Zoster Virus Vasculopathy: An Under-Recognized Entity

Varicella zoster virus (VZV) vasculopathy is a rare yet potentially severe neurological manifestation resulting from VZV reactivation, primarily affecting immunocompromised individuals. We present a case report of a 61-year-old male with VZV vasculopathy who initially presented with herpes zoster ophthalmicus, subsequently complicated by meningoencephalitis and an acute infarct in the territory of the left middle cerebral artery (MCA). Imaging revealed acute and chronic infarcts in the capsuloganglionic regions, accompanied by thickening and enhancement of the left MCA wall. Treatment involved a 14-day course of intravenous acyclovir, supplemented with oral prednisolone, resulting in modest clinical improvement. VZV vasculopathy represents an infrequently acknowledged neurological syndrome, particularly prevalent among immunocompromised individuals. Early recognition and appropriate intervention offer promise in ameliorating outcomes for affected patients. This case emphasizes the importance of including VZV vasculopathy in the differential diagnosis of neurological deficits, especially within high-risk populations.

The rare manifestations in tuberculous meningoencephalitis: a review of available literature

Aim: Tuberculous meningitis is an infectious disease of the central nervous system caused by Mycobacterium tuberculosis (M. tuberculosis). It mainly involves the meninges and brain parenchyma, as well as the spinal cord and meninges; Disability and mortality rates are high. In recent years, due to the increase of drug-resistant tuberculosis patients, population mobility and the prevalence of acquired immune deficiency syndrome, the incidence rate of tuberculosis has increased significantly, and tuberculous meningitis has also increased.Methods: At present, tuberculosis is still a worldwide infectious disease that seriously threatens human health, especially in underdeveloped and developing countries. China is the largest developing country in the world with a large population.Results: The situation of tuberculosis prevention and control is grim. Its disability rate is the highest in tuberculosis infection. In addition to the common non-specific manifestations, tuberculous meningoencephalitis may also have rare manifestations of stroke, hearing loss and visual loss.Conclusion: Understanding and timely improvement of corresponding examinations and targeted treatment will help improve the prognosis of patients.

De novo intracranial aneurysm formation in SARS-CoV-2 infection: first report of a yet unknown complication

BACKGROUND AND IMPORTANCE

COVID-19 is a viral infection that mainly affects the respiratory tract, but can also cause multiple inflammatory reactions, including neurological and cerebrovascular manifestations. We report the case of a COVID-19 patient who developed 'de novo' multiple cerebral aneurysms with no risk factors for aneurysm formation.

CLINICAL PRESENTATION

A 55-year-old man with SARS-CoV-2 infection came to our attention for left eye blindness accompanied by ptosis, palpebral chemosis and retro-orbital pain. Brain CT and CT-angiography were negative for hemorrhages and for vascular malformations. Repeated intracerebral hemorrhages and neurological deterioration then occurred, and a new CT-angiography showed multiple intracranial aneurysms that were not present before.

CONCLUSION

Intracranial aneurysm formation as a complication of COVID-19 has not been previously reported. As other viral infections do, COVID-19 may be able to determine a vascular damage that can ultimately lead to development of an aneurysm. It is reasonable to hypothesize an involvement of the renin-angiotensin system as a pathogenic mechanism. A conservative therapy aiming at inflammatory modulation and vascular damage prevention may be warranted in these patients.

Cryptococcal meningitis and cerebral vasculitis in a patient with primary intestinal lymphangiectasia: a case report

Primary intestinal lymphangiectasia (Waldmann's disease) is a rare exudative enteropathy without precisely assessed infectious risk. We report the case of a 49-year-old male patient with meningitis and cerebral vasculitis due to Cryptococcus neoformans complicating Waldmann's disease diagnosed 12 years ago. The treatment combined liposomal amphotericin B, 3 mg/kg daily plus flucytosine 25 mg/kg/6 h, both intravenously during 15 days, then fluconazole 800 mg daily during 8 weeks, and finally 200 mg daily indefinitely. Dexamethasone 0.4 mg/kg daily during the first week was gradually decreased over 2 months. The outcome was good, and the patient is still followed 3 years later without any recurrence.

Central Nervous System Vasculitis: Primary Angiitis of the Central Nervous System and Central Nervous System Manifestations of Systemic Vasculitis

Central nervous system vasculitis (CNSV) is a group of disorders leading to inflammatory vasculopathy within the brain, spinal cord, and leptomeninges. CNSV is divided into primary angiitis of the central nervous system (PACNS) and secondary CNSV based on the underlying etiology. PACNS is a rare inflammatory disorder with poorly understood pathophysiology and heterogeneous and highly variable clinical features. The diagnosis depends on a combination of clinical and laboratory variables, multimodal imaging, and histopathological examination as well as exclusion of mimics. Several systemic vasculitides, infectious etiologies and connective tissue disorders have been shown to cause secondary CNSV and require prompt recognition.

Diagnostic Evaluation of Stroke Etiology

OBJECTIVE

Precise therapies require precise diagnoses. This article provides an evidence-based approach to confirming the diagnosis of ischemic stroke, characterizing comorbidities that provide insights into the pathophysiologic mechanisms of stroke, and identifying targets for treatment to optimize the prevention of recurrent stroke.

LATEST DEVELOPMENTS

Identifying the presence of patent foramen ovale, intermittent atrial fibrillation, and unstable plaque is now routinely included in an increasingly nuanced workup in patients with stroke, even as ongoing trials seek to clarify the best approaches for treating these and other comorbidities. Multicenter trials have demonstrated the therapeutic utility of patent foramen ovale closure in select patients younger than age 60 years. Insertable cardiac monitors detect atrial fibrillation lasting more than 30 seconds in about one in ten patients monitored for 12 months following a stroke. MRI of carotid plaque can detect unstable plaque at risk of being a source of cerebral embolism.

ESSENTIAL POINTS

To optimize the prevention of recurrent stroke, it is important to consider pathologies of intracranial and extracranial blood vessels and of cardiac structure and rhythm as well as other inherited or systemic causes of stroke. Some aspects of the stroke workup should be done routinely, while other components will depend on the clinical circumstances and preliminary testing results.

Distinct lesion features and underlying mechanisms in patients with acute multiple infarcts in multiple cerebral territories

Objective

To determine the etiology spectrum and lesion distribution patterns of patients with acute multiple infarcts in multiple cerebral territories (AMIMCT) and provide guidance for treatment and prevention strategies in these patients.

Methods

Patients with acute ischemic stroke diagnosed using diffusion-weighted imaging (DWI) were consecutively included in this study between June 2012 and Apr 2022. AMIMCT was defined as non-contiguous focal lesions located in more than one cerebral territory with acute neurological deficits. We retrospectively analyzed the clinical and imaging characteristics, etiology spectra and underlying mechanisms in patients with and without AMIMCT. Infarct lesion patterns on DWI and their relevance to etiology were further discussed.

Results

A total of 1,213 patients were enrolled, of whom 145 (12%) were diagnosed with AMIMCT. Patients with AMIMCT tended to be younger (P = 0.016), more often female (P = 0.001), and exhibited less common conventional vascular risk factors (P < 0.05) compared to those without AMIMCT. The constitution of the Trial of Org 10,172 in Acute Stroke Treatment classification was significantly different between patients with and without AMIMCT (P = 0.000), with a higher proportion of stroke of other determined causes (67.6% vs. 12.4%). For detailed etiologies, autoimmune or hematologic diseases were the most common (26.2%) etiologies of AMIMCT, followed by periprocedural infarcts (15.2%), cardioembolism (12.4%), tumor (12.4%), large artery atherosclerosis (10.3%), and sudden drop in blood pressure (8.3%). Hypercoagulability and systemic hypoperfusion are common underlying mechanisms of AMIMCT. Distinctive lesion distribution patterns were found associated with stroke etiologies and mechanisms in AMIMCT. Most of patients with large artery atherosclerosis (73.3%), autoimmune/hematologic diseases (57.9%) manifested the disease as multiple infarct lesions located in bilateral supratentorial regions. However, 66.7% of cardioembolism and 83.8% of cardiovascular surgery related stroke presented with both supratentorial and infratentorial infarct lesions.

Conclusion

The etiologies and mechanisms of patients with AMIMCT were more complex than those without AMIMCT. The distribution characteristics of infarct lesions might have important implications for the identification of etiology and mechanism in the future, which could further guide and optimize clinical diagnostic strategies.

Human Neurocysticercosis: An Overview

Human cysticercosis is caused by ingestion of T. solium eggs from taenia carriers. Neurocysticercosis (NCC), defined as the infection of the CNS and the meninges by the larval stage of Taenia solium, is the most common helminthic infection of the CNS worldwide. Parasites may lodge in brain parenchyma, subarachnoid space, ventricular system, or spinal cord, causing pathological changes that account for the pleomorphism of this disease. Seizures/epilepsy are the most common clinical manifestation, but other patients present with headache, focal deficits, intracranial hypertension, or cognitive decline. Accurate diagnosis of NCC is possible after interpretation of clinical data together with findings of neuroimaging studies and results of immunological tests. However, neuroimaging studies are fundamental for diagnosis because immunological test and clinical manifestations only provide circumstantial evidence of NCC. The introduction of cysticidal drugs changed the prognosis of most NCC patients. These drugs have been shown to reduce the burden of infection and to improve the clinical course of the disease in many patients. Efforts should be directed to eradicate the disease through the implementation of control programs against all the steps in the life cycle of T. solium, including carriers of the adult tapeworm, infected pigs, and eggs in the environment.

When modern diagnostics is challenged by a historical disease: A case report

RATIONALE

Syphilis is a bacterial, systemic infectious disease caused by Treponema pallidum spirochetes, which spread rapidly through the body affecting various organs. The term neurosyphilis (NS) refers to a CNS infection that can occur at any stage of the disease. The lack of a gold standard for the diagnosis of NS greatly hinders diagnosis, which must be based mainly on clinical assessment.

PATIENT CONCERNS

A 58-year-old man reported dizziness and headache for a week and right-sided hearing impairment, with suspected transient cerebral ischemic attack. A month later he experience transient speech disturbance and suspected cerebral ischemic stroke.

DIAGNOSIS

MRI showed fresh ischemic lesions with a diameter up to 10 mm in the deep brain structures on the left side and foci of subacute ischemia also in the deep structures and the brain stem. Cerebrospinal fluid examination showed positive Pandy's reaction, doubtful Noone-Apelt reaction, increased protein level and decreased glucose level. The reactive result of the USR test performed (VDRL) finally allowed the diagnosis of symptomatic CNS syphilis.

INTERVENTIONS

Empiric treatment for bacterial meningitis was administered. The patient was transferred to the Department of Infectious Diseases for further treatment.

OUTCOMES

The diagnosis has been confirmed at the Department of Infectious Diseases after repeating CSF analysis including VDRL and FTA-ABS.

LESSON

Symptoms of NS are nonspecific, hence the diagnostic process is not straightforward. Despite the availability of modern diagnostic techniques, establishing a final diagnosis was challenging, but the patient ultimately received appropriate treatment. It is important to remember that syphilis is not only a disease known from history lessons but is still present in modern times and its incidence is increasing.

Neurocysticercosis With Internal Carotid Artery and Middle Cerebral Artery Vasculitis and Stenosis

A seven-year-old female child presented with sub-acute onset headache, vomiting, and aphasia with right-sided upper motor neuron (UMN) type hemiparesis and ipsilateral UMN type facial nerve weakness. Her coagulation profile and thrombotic profile were normal. MRI brain with magnetic resonance angiography (MRA) detected neurocysticercosis causing secondary vasculitis and narrowing of supraclinoid left internal carotid artery (ICA) and middle cerebral artery (MCA). The patient was given aspirin along with steroids and albendazole. She improved gradually, and her hemiparesis and facial nerve palsy improved completely by three months and aphasia by four months.

Role of exosomes in the pathogenesis, diagnosis, and treatment of central nervous system diseases

Central nervous system (CNS) diseases, such as multiple sclerosis, Alzheimer's disease (AD), and Parkinson’s disease (PD), affect millions of people around the world. Great efforts were put in disease related research, but few breakthroughs have been made in the diagnostic and therapeutic approaches. Exosomes are cell-derived extracellular vesicles containing diverse biologically active molecules secreted by their cell of origin. These contents, including nucleic acids, proteins, lipids, amino acids, and metabolites, can be transferred between different cells, tissues, or organs, regulating various intercellular cross-organ communications and normal and pathogenic processes. Considering that cellular environment and cell state strongly impact the content and uptake efficiency of exosomes, their detection in biological fluids and content composition analysis potentially offer a multicomponent diagnostic readout of several human diseases. Recently, studies have found that aberrant secretion and content of exosomes are closely related to the pathogenesis of CNS diseases. Besides, loading natural cargoes, exosomes can deliver drugs cross the blood brain barrier, making them emerging candidates of biomarkers and therapeutics for CNS diseases. In this review, we summarize and discuss the advanced research progress of exosomes in the pathological processes of several CNS diseases in regarding with neuroinflammation, CNS repair, and pathological protein aggregation. Moreover, we propose the therapeutic strategies of applying exosomes to the diagnosis, early detection, and treatment of CNS diseases.

Cerebral Infarction and Evan's Ratio on MRI Affect the Severity and Prognosis of Tuberculosis Meningitis Patients

Background: Magnetic resonance imaging (MRI) is widely used in the diagnosis of tuberculous meningitis (TBM) and its complications. We aimed to explore the relationship between MRI features and neurological deficits and TBM patients’ prognosis. Methods: patients diagnosed with TBM were subjected to a neurological evaluation on admission and divided into groups based on the Medical Research Council (MRC) scale. After several years of follow-up, the patients were further divided into groups according to the Modified Rankin Score (MRS). Their MR images were analyzed for meningeal enhancement, tuberculomas, infarction, hydrocephalus, and abscess, including the location and size of the lesion. Any changes in MRI features during the follow-up were recorded. MRI features between groups were compared, and the relationship between dynamic changes in images and Rankin grading was explored. Results: We found significant differences in acute cerebral infarction (ACI) and old cerebral infarctions (OCI) between the MRC groups, and the ORs of ACI and OCI were 21.818 (95% CI: 2.440−195.075) and 6.788 (95% CI: 1.516−30.392), respectively. There were significant differences in ACI, OCI, and Evan’s ratio between the MRS groups (p < 0.05), and the ORs of ACI, OCI, and hydrocephalus were 6.375 (95% CI: 1.501−27.080), 5.556 (95% CI: 1.332−23.177), and 9.139 (95% CI: 2.052−40.700), respectively. The changes of Evan’s ratio were related to the MRS grading (r = 0.335, p = 0.040). Conclusions: For patients with TBM, the presence of ACI or OCI is associated with neurological deficits, and ACI, OCI, and hydrocephalus can be regarded as poor prognostic predictors. Changes in Evan’s ratio will affect the outcome.

Locked-in Syndrome Due to Meningovascular Syphilis: A Case Report and Literature Review

We herein report a 46-year-old man presenting with locked-in syndrome secondary to meningovascular syphilis. Brain magnetic resonance imaging (MRI) demonstrated multiple acute infarctions in the left ventromedial pons, right basis pontis, and left basal ganglia. His locked-in syndrome was hypothesized to have been caused by thrombosis of the small paramedian branches of the basilar artery due to syphilitic arteritis. This is a unique case of bilateral ventromedial pontine infarction caused by meningovascular syphilis that presented as locked-in syndrome. Meningovascular syphilis should be included in the differential diagnosis of uncommon stroke, particularly in young men.

A case of ischemic stroke secondary to varicella-zoster virus meningoencephalitis

Varicella-zoster virus (VZV) lurks in cranial nerves and other brain ganglias after infection. Because middle cerebral artery (MCA) receives the ipsilateral trigeminal ganglia afferent innervations, the reactivated VZV infects the adventitia and intima of cerebral artery wall probably through this way and causes vascular inflammation, finally resulting in artery remodeling, vessel occlusion, and ischemia. In fact, there is a growing clinical recognition that there is an association between VZV reactivation and subsequent stroke. Here, we showed a case of ischemic stroke secondary to varicella-zoster virus meningoencephalitis and reviewed the literature to emphasize the importance of VZV-associated vasculopathy.

Risk factors of intracranial infection in patients after intracranial aneurysm surgery: Implication for treatment strategies

Postoperative intracranial infection after intracranial aneurysm is relatively common in clinical setting; it is necessary to analyze the clinical risk factors of postoperative intracranial infection, to provide reliable evidence to the management of aneurysm.Patients with intracranial aneurysm admitted from January 1, 2016, to November 30, 2020, are included. We collected the patient's personal and treatment data, and analyzed the risk factors of intracranial infection by multivariate logistic regression analysis. We compared the cerebrospinal fluid (CSF) indicators and serological indicators and analyzed their correlation with intracranial infection by spearman analysis.A total of 236 patients with intracranial aneurysm were included; the incidence of postoperative intracranial infection was 12.71%. There were significant differences in the diabetes, intraoperative aneurysm rupture, intraoperative CSF leakage, duration of surgery, and estimated blood loss between infection and non-infection group. Logistic regression indicated that diabetes [odds ratio (OR) 2.053, 95% confidence interval (95% CI) 1.092∼3.385], intraoperative aneurysm rupture (OR 2.239, 95% CI 1.173∼4.312), intraoperative CSF leakage (OR 2.168, 95% CI 1.033∼3.451), duration of surgery ≥360 minutes (OR 1.926, 95% CI 1.108∼2.655), and estimated blood loss ≥125 mL (OR 2.459, 95% CI 1.854∼3.447) were the independent risk factors of postoperative intracranial infection in patients with aneurysm surgery (all P < .05). Klebsiella pneumoniae, Escherichia coli, and Staphylococcus epidermidis were the top 3 commonly seen pathogens. Spearman analyses indicated that PCT, CRP, LA, LDH were all correlated with intracranial infection (all P < .05).There are multiple factors for the postoperative intracranial infection in patients with aneurysm. Coping strategies should be formulated targeted on those risks to improve the prognosis of patients.

Successful Intravenous Thrombolysis in Ischemic Stroke Caused by Tuberculous Meningitis: A Case Report

Tuberculous meningitis (TBM) has a variety of clinical manifestations and complications, and ischemic stroke is a common complication of TBM. However, there is no established prevention or treatment for stroke associated with TBM, and the safety and efficiency of thrombolysis in acute stroke caused by TBM remain unknown. Herein, we present a case of successful intravenous thrombolysis in ischemic stroke caused by TBM. A 50-year-old male patient with cerebral infarction had substantially improved neurological function after intravenous thrombolysis, and he was subsequently found to have TBM. Our findings suggest that intravenous thrombolysis might be an effective acute treatment method for infectious stroke.

Progressive Stroke Caused by Neurosyphilis With Concentric Enhancement in the Internal Cerebral Artery on High-Resolution Magnetic Resonance Imaging: A Case Report

Background: Neurosyphilis can initially present as a stroke. However, the general management strategy for stroke may not be effective for this condition. Intracranial vessel wall imaging indicating arteritis can help differentiate neurosyphilis from other causes of stroke.

Case presentation: A 59-year-old Chinese woman presented with an acute infarct in the left basal ganglia and multiple stenoses in the bilateral middle cerebral arteries, anterior cerebral artery, and basilar artery, which aggravated twice, despite antiplatelet treatment. High-resolution magnetic resonance imaging (HR-MRI) suggested concentric enhancement in the left middle cerebral artery. Treponema pallidum test results were positive, suggesting neurosyphilis.

Conclusions: HR-MRI provides valuable information regarding arteritis, which is helpful in differentiating neurosyphilis from other causes of stroke. Antiplatelet medication should be used judiciously for neurosyphilis-related stroke.

Pathogens in Vasculitis: Is It Really Idiopathic?

Vasculitis is an autoimmune disease characterized by the infiltration of leukocytes in blood vessels. An increasing number of studies on human and animal models have implicated various microorganisms in the pathogenesis of vasculitis. Previous studies have shown the presence of infectious agents, including viruses, bacteria, and fungi, in diseased vessels. However, despite continued research, the link between infection and vasculitis is not fully understood, possibly owing to the lack of appropriate animal models that mirror human disease and the technical limitations of pathogen detection in blood vessels. Among the pathogen-induced animal models, Candida albicans water-soluble fraction (CAWS)-induced coronary arteritis is currently considered one of the representative models of Kawasaki (KD) disease. Advances in metagenomic next-generation sequencing have enabled the detection of all nucleic acids in tissue, which can help identify candidate pathogens, including previously unidentified viruses. In this review, we discuss the findings from reports on pathogen-associated vasculitis in animal models and humans, with a specific focus on the investigation of the pathogenesis of vasculitis. Further studies on animal models and microbes in diseased vessels may provide important insights into the pathogenesis of vasculitis, which is often considered an idiopathic disease.

Ruptured cerebral pseudoaneurysm in an adolescent as an early onset of COVID-19 infection: case report

The clinical manifestations of coronavirus disease 2019 (COVID-19) are non-specific and multi-inflammatory. They vary from mild to severe manifestations that can be life-threatening. The association of SARS-CoV-2 infection and pseudoaneurysm formation or rupture of an already existing aneurysm is still unexplored. Several mechanisms may be involved, including the direct destruction to the artery by the viral infection or through the release of the inflammatory cytokines. We are presenting a case of a 13-year-old girl with a ruptured cerebral pseudoaneurysm of the left middle cerebral artery (M2 segment) with severe intracerebral hemorrhage as the earliest manifestation of COVID-19 infection.

Sepsis-associated encephalopathy and septic encephalitis: an update

INTRODUCTION

Sepsis-associated encephalopathy (SAE) and septic encephalitis (SE) are associated with increased mortality, long-term cognitive impairment, and focal neurological deficits.

AREAS COVERED

The PUBMED database was searched 2016-2020. The clinical manifestation of SAE is delirium, SE additionally is characterized by focal neurological symptoms. SAE is caused by inflammation with endothelial/microglial activation, increase of permeability of the blood-brain-barrier, hypoxia, imbalance of neurotransmitters, glial activation, axonal, and neuronal loss. Septic-embolic (SEE) and septic-metastatic encephalitis (SME) are characterized by focal ischemia (SEE) and small abscesses (SME). The continuum between SAE, SME, and SEE is documented by imaging techniques and autopsies. The backbone of treatment is rapid optimum antibiotic therapy. Experimental approaches focus on modulation of inflammation, stabilization of the blood-brain barrier, and restoration of membrane/mitochondrial function.

EXPERT OPINION

The most promising diagnostic approaches are new imaging techniques. The most important measure to fight delirium remains establishment of daily structure and adequate sensory stimuli. Dexmedetomidine and melatonin appear to reduce the frequency of delirium, their efficacy in SAE and SE remains to be established. Drugs already licensed for other indications or available as food supplements which may be effective in SAE are statins, L-DOPA/benserazide, β-hydroxybutyrate, palmitoylethanolamide, and tetracyclines or other bactericidal non-lytic antibiotics.

[Infection associated cerebral vasculitis]

Infections are a frequent cause of cerebral vasculitis, important to diagnose because a specific treatment may be required. Infection-associated vasculitis can be caused by angiotropic pathogens (varicella zoster virus, syphilis, aspergillus). They can be associated with subarachnoidal meningitis (tuberculosis, pyogenic meningitis, cysticercosis). They can appear contiguously to sinuses or orbital infection (aspergillosis, mucormycosis). Finally, they also may be due to an immune mechanism in the context of chronic infections (hepatitis B virus, hepatitis C virus, human immunodeficiency virus). Cerebral vasculitis are severe conditions and their prognosis is directly linked to early recognition and diagnosis. Infectious causes must therefore be systematically considered ahead of cerebral vasculitis, and the appropriate investigations must be determined according to the patient's clinical context. We propose here an update on the infectious causes of cerebral vasculitis, their diagnosis modalities, and therapeutic options.

Potential mechanisms of hemorrhagic stroke in elderly COVID-19 patients

The novel severe acute respiratory syndrome coronavirus 2 is the causative agent of coronavirus disease 2019, a new human infectious disease. While fever, cough, and respiratory distress are typical first symptoms, a fraction of those affected present instead with neurological symptoms suggestive of central nervous system compromise. This review summarizes the potential contribution of coronavirus disease 2019 to hemorrhagic stroke in the elderly and proposes possible mechanisms. Reports show that the most affected patients have underlying chronic diseases such as hypertension and diabetes, which are two key risk factors for hemorrhagic stroke. Angiotensin-converting enzyme 2 is the main host cell surface receptor interacting with the severe acute respiratory syndrome coronavirus 2 spike glycoprotein to allow viral entry and infection. We speculate that ensuing downregulation of angiotensin-converting enzyme 2 expression may compound the risk conferred by pre-existing comorbidities and critically influence the pathogenesis of hemorrhagic stroke by elevating blood pressure and impairing cerebrovascular endothelial function. Additionally, both age- and/or disease-related immune dysfunction and enhanced catecholamine release secondary to anxiety and stress may also aggravate central nervous system symptoms of severe acute respiratory syndrome coronavirus 2 infection. Thus, assessment of systemic inflammatory biomarkers and tight control of hemodynamic parameters upon admission are crucial to minimize mortality and morbidity in coronavirus disease 2019 patients with central nervous system symptoms suggestive of incipient stroke.

Stroke Risk Following Infection in Patients with Continuous-Flow Left Ventricular Assist Device

BACKGROUND

Infection has been associated with stroke in patients with left ventricular assist devices (LVAD); however, little data exist on the timing, type and mortality impact of infection-related stroke.

METHODS

Prospectively collected data of HeartMate II (N = 332) and HeartWare (N = 70) LVAD patients from a single center were reviewed. Only strokes (ischemic or hemorrhagic) that occurred within 6 weeks following a LVAD infection were considered in analyses. The association between LVAD infections (wound, pump pocket, driveline and/or bloodstream infection [BSI]), specific pathogens and ischemic and hemorrhagic strokes was evaluated using multivariable logistic regression analysis. The impact of infection-related stroke on cumulative survival was assessed using Kaplan-Meier analysis.

RESULTS

Of 402 patients, LVAD infection occurred in 158 (39%) including BSI in 107 (27%), driveline infection in 67 (17%), wound infection in 31 (8%) and pump pocket infection in 24 (6%). LVAD infection-related stroke occurred in 20/158 (13%) patients in a median of 4 days (0-36 days) from documented infection. In multivariable analysis, ischemic stroke was associated with wound infection (aOR 9.0, 95% CI 2.4-34.0, P = 0.001) and BSI (aOR 7.7, 95% CI 0.9-66.0, P = 0.064), and hemorrhagic stroke was associated with BSI in 100% of cases (P = 0.01). There was no association with driveline or pump pocket infection. The cumulative survival rate among patients with infection-related stroke was significantly lower compared to those with LVAD infection but no stroke (log-rank P < 0.001). There was a trend toward shorter stroke-free survival among patients with LVAD infection.

CONCLUSIONS

LVAD infections, particularly BSI, are significantly associated with stroke, and infection-related stroke conferred significantly lower cumulative survival.

Cerebral HSV-1 Vasculitis as a Fatal Complication of Immunosuppression in Non-Hodgkin´s Lymphoma: A Case Report and Review of the Literature

Patients with lymphoma are predisposed to infection because of the immunocompromised state related to the disease itself and as a consequence of chemo-/radiotherapy. Here, we report a case of Herpes-simplex virus encephalitis (HSE) in an immunosuppressed patient with splenic marginal zone lymphoma (SMZL), a rare indolent variant of non-Hodgkin´s lymphoma (NHL). The course was complicated febrile neutropenia and HSV-1-related cerebral vasculitis causing progressive ischemic stroke. This case illustrates the expanding spectrum of atypical clinical and radiological manifestations of HSE in patients treated with myelotoxic drugs. Moreover, we summarize the few central nervous system manifestations of SMZL reported in the literature and discuss distinct causes of neurological deterioration in patients with NHL.

Cerebrovascular manifestations of herpes simplex virus infection of the central nervous system: a systematic review

BACKGROUND

Intracerebral hemorrhage and ischemic stroke are increasingly recognized complications of central nervous system (CNS) infection by herpes simplex virus (HSV).

AIM OF THE STUDY

To analyze clinical, imaging, and laboratory findings and outcomes of cerebrovascular manifestations of HSV infection.

METHODS

Systematic literature review from January 2000 to July 2018.

RESULTS

We identified 38 patients (median age 45 years, range 1-73) comprising 27 cases of intracerebral hemorrhage, 10 of ischemic stroke, and 1 with cerebral venous sinus thrombosis. Intracerebral hemorrhage was predominantly (89%) a complication of HSV encephalitis located in the temporal lobe. Hematoma was present on the first brain imaging in 32%, and hematoma evacuation was performed in 30% of these cases. Infarction was frequently multifocal, and at times preceded by hemorrhage (20%). Both a stroke-like presentation and presence of HSV encephalitis in a typical location were rare (25% and 10%, respectively). There was evidence of cerebral vasculitis in 63%, which was exclusively located in large-sized vessels. Overall mortality was 21% for hemorrhage and 0% for infarction. HSV-1 was a major cause of hemorrhagic complications, whereas HSV-2 was the most prevalent agent in the ischemic manifestations.

CONCLUSION

We found a distinct pathogenesis, cause, and outcome for HSV-related cerebral hemorrhage and infarction. Vessel disruption within a temporal lobe lesion caused by HSV-1 is the presumed mechanism for hemorrhage, which may potentially have a fatal outcome. Brain ischemia is mostly related to multifocal cerebral large vessel vasculitis associated with HSV-2, where the outcome is more favorable.

Treatment of Syphilis-Associated Cerebral Vasculitis: Reappearance of an Old Question

BACKGROUND

Cerebral vasculitis caused by neurosyphilis is a re-emerging problem with diagnostic and treatment issues, especially for human immunodeficiency virus patients.

METHODS

We present a case of relapsing syphilis-associated cerebral vasculitis, despite the recommended first-line antibiotic treatment, that was successfully treated with a second intravenous penicillin G course and corticosteroids.

RESULTS

A 50-year old man went to the emergency department for bilateral episodes of red and painful eyes with progressive but severe visual acuity loss. He was diagnosed with bilateral panuveitis and neurosyphilis favored by an unknown human immunodeficiency virus infection with a CD4 count of 236 mm³. Despite appropriate and well-conducted treatment including intravenous penicillin G, short-term corticosteroid, and highly active antiretroviral therapy, a symptomatic relapse of the syphilis-associated cerebral vasculitis occurred. After a second course of penicillin and corticosteroids, he made a complete recovery.

CONCLUSIONS

Neurosyphilis and human immunodeficiency virus co-infection is a reappearing challenging situation that should be considered with care by physicians because recommended antibiotic treatment sometimes fails. Corticosteroid therapy should be discussed in case of cerebral vasculitis.

MCA-to-MCA Bypass with Interposition Graft for Ruptured Mycotic Middle Cerebral Artery Aneurysm

Mycotic aneurysm, also referred to as infected aneurysm, is a rare entity that may result from the bacterial infection or infective endocarditis.^1-3 The treatment options include conservative medication and endovascular or direct microsurgical intervention.^1,4,5 However, the optimal strategy remains unknown and cerebral revascularization may be required in some rare cases.⁶ In this surgical video, we demonstrate a distal middle cerebral artery (MCA) mycotic aneurysm that we treated by intracranial-intracranial bypass with an interpositional graft. Our patient is a 53-year-old male who presented with a 6-day history of severe headache. He was subsequently admitted to our institution. Preoperative computed tomography angiography showed a left temporal hematoma (>30 mL) and an opercular segment of the MCA (M3) aneurysm, which was highly suspicious for mycotic origin. A standard frontotemporal craniotomy was carried out with preservation of superficial temporal artery (STA). Following the sylvian fissure dissection, the aneurysm was exposed with the characteristics of a thick wall and an undefinable neck, which made direct clip application difficult. The aneurysm was resected initially, and 2 cut ends were reconnected by an STA graft. Following arterial reconstruction, intraoperative Doppler revealed a patent status of the interpositional graft vessel. Postoperatively, no neurologic deficit was observed and computed tomography angiography demonstrated total elimination of the aneurysm without stenosis of the graft vessel. Low-molecular dextran was prescribed rather than aspirin, as there was concern for hemorrhage. Antibiotic treatment was used for at least 4 weeks, and the patient was transferred to the inpatient cardiology team for management of endocarditis. A 4-month follow-up angiogram showed a patent STA and excellent left distal MCA blood flow (Video 1). The favorable outcome of this case revealed that MCA-to-MCA bypass with interpositional graft is a safe, effective method for the unclippable cerebral aneurysm. As other authors have asserted, a full dose of long-term antibiotic therapy remains essential following intervention.⁷ Meanwhile, dextran has proved to be a viable alternative for anticoagulation during perioperative management of bypass surgery.^8,9.

Neurological complications of Zika virus infection

INTRODUCTION

Zika virus (ZIKV) disease is a vector-borne infectious disease transmitted by Aedes mosquitoes. Recently, ZIKV has caused outbreaks in most American countries. Areas covered: Publications about neurological complications of ZIKV infection retrieved from pubmed searchers were reviewed, and reference lists and relevant articles from review articles were also examined. Vertical/intrauterine transmission leads to congenital infection and causes microcephaly and congenital ZIKV syndrome. ZIKV preferentially infects human neural progenitor cells and triggers cell apoptosis. ZIKV RNA has been identified in foetal brain tissue and brains of microcephalic infants who died; amniotic fluid and placentas of pregnant mothers; and umbilical cord, cerebro-spinal fluid and meninges of newborns. The increase in the number of Guillain-Barre syndrome (GBS) cases during the ZIKV outbreak in the Americas provides epidemiological evidence for the link between ZIKV infection and GBS. Less frequently reported ZIKV neurological complications include encephalitis/meningoencephalitis, acute disseminated encephalomyelitis, myelitis, cerebrovascular complications (ischemic infarction; vasculopathy), seizures and encephalopathy, sensory polyneuropathy and sensory neuronopathy. Analysis of GBS incidence could serve as an epidemiological 'marker' or sentinel for ZIKV disease and other neurological complications associated to ZIKV. Expert commentary: An expanding spectrum of neurological complications associated with ZIKV infection is being recognised.

Pediatric stroke related to Lyme neuroborreliosis: Data from the Swiss NeuroPaediatric Stroke Registry and literature review

BACKGROUND

Cerebrovascular complications of Lyme neuroborreliosis (LNB) are poorly documented in the paediatric population.

METHODS

We performed a retrospective analysis from prospectively registered cases of acute ischemic stroke (AIS) from the Swiss NeuroPaediatric Stroke Registry (SNPSR) from 2000 to 2015. Only cases with serologically confirmed LNB were included. In addition, a literature review on paediatric stroke cases secondary to Lyme neuroborreliosis in the same time frame was performed.

RESULTS

4 children out of 229 children with arterial ischemic childhood stroke and serologically confirmed LNB were identified in the SNPSR giving a global incidence of 1.7%. Median age was 9.9 years. A prior history of tick bites or erythema migrans (EM) was reported in two cases. Clinical presenting signs were suggestive of acute cerebellar/brainstem dysfunction. On imaging, three children demonstrated a stroke in the distribution of the posterior inferior cerebellar artery. The remaining fourth child had a "stroke-like" picture with scattered white matter lesions and a multifocal vasculitis with prominent basilar artery involvement. Lymphocytic pleocytosis as well as intrathecal synthesis of Borrelia burgdorferi antibodies were typical biological features. Acute intravenous third generation cephalosporins proved to be effective with rapid improvement in all patients. No child had recurrent stroke. Data from the literature concerning eight patients gave similar results, with prominent posterior circulation stroke, multifocal vasculitis and abnormal CSF as distinctive features.

CONCLUSIONS

Lyme Neuroborreliosis accounts for a small proportion of paediatric stroke even in an endemic country. The strong predilection towards posterior cerebral circulation with clinical occurrence of brainstem signs associated with meningeal symptoms and CSF lymphocytosis are suggestive features that should rapidly point to the diagnosis. This can be confirmed by appropriate serological testing in the serum and CSF. Clinicians must be aware of this rare neurological complication of Lyme disease that demands specific antibiotic treatment.

Infectious diseases causing autonomic dysfunction

OBJECTIVES

To review infectious diseases that may cause autonomic dysfunction.

METHODS

Review of published papers indexed in medline/embase.

RESULTS

Autonomic dysfunction has been reported in retrovirus (human immunodeficiency virus (HIV), human T-lymphotropic virus), herpes viruses, flavivirus, enterovirus 71 and lyssavirus infections. Autonomic dysfunction is relatively common in HIV-infected patients and heart rate variability is reduced even in early stages of infection. Orthostatic hypotension, urinary dysfunction and hypohidrosis have been described in tropical spastic paraparesis patients. Varicella zoster reactivation from autonomic ganglia may be involved in visceral disease and chronic intestinal pseudo-obstruction. Autonomic and peripheral nervous system dysfunction may happen in acute tick-borne encephalitis virus infections. Hydrophobia, hypersalivation, dyspnea, photophobia, and piloerection are frequently observed in human rabies. Autonomic dysfunction and vagal denervation is common in Chagas disease. Neuronal depopulation occurs mainly in chagasic heart disease and myenteric plexus, and megacolon, megaesophagus and cardiomyopathy are common complications in the chronic stage of Chagas disease. Parasympathetic autonomic dysfunction precedes left ventricle systolic dysfunction in Chagas disease. A high prevalence of subclinical autonomic neuropathy in leprosy patients has been reported, and autonomic nerve dysfunction may be an early manifestation of the disease. Autonomic dysfunction features in leprosy include anhidrosis, impaired sweating function, localised alopecia ,and reduced heart rate variability. Urinary retention and intestinal pseudo-obstruction have been described in Lyme disease. Diphtheritic polyneuropathy, tetanus and botulism are examples of bacterial infections releasing toxins that affect the autonomic nervous system.

CONCLUSIONS

Autonomic dysfunction may be responsible for additional morbidity in some infectious diseases.