The varicella zoster virus vasculopathies: clinical, CSF, imaging, and virologic features

Herpes simplex virus type 2 encephalitis in a child with chronic progressive white matter lesions: A case report

RATIONALE

This case is a rare manifestation of central nervous system infection of Herpes simplex virus (HSV)-2. Due to few studies in China, it provides a pathological basis for further diagnosis and treatment of HSV-2.

PATIENT CONCERNS

We describe a patient with HSV-2 virus infection who was diagnosed with HSV-2 encephalitis in a Chinese patient.

DIAGNOSIS

Based on brain biopsy and pathological findings, the patient was diagnosed with HSV-2 encephalitis.

INTERVENTIONS

Hormone and antiviral therapy were given.

OUTCOME

The patient eventually died.

LESSONS

The diagnosis and differential diagnosis of the disease is very difficult. Its differential diagnosis include cerebrovascular disease, bacteria or fungi and other viral infection of the brain.

Herpes Zoster and Long-Term Risk of Cardiovascular Disease

Background We investigated the longitudinal association of herpes zoster (HZ), commonly known as "shingles," and long-term risk of stroke or coronary heart disease (CHD) among participants in 3 large US cohorts, the NHS (Nurses' Health Study), NHS II (Nurses' Health Study II), and HPFS (Health Professionals Follow-Up Study). Methods and Results Participants were 79 658 women in the NHS (2000-2016), 93 932 women in the NHS II (2001-2017), and 31 440 men in the HPFS (2004-2016), without prior stroke or CHD. Information on HZ, stroke, and CHD was collected on biennial questionnaires and confirmed by medical record review. Cox proportional hazards regression models were used to estimate multivariable-adjusted hazard ratios for stroke and for CHD according to years since HZ compared with never HZ. During >2 million person-years of follow-up, 3603 incident stroke and 8620 incident CHD cases were documented. History of HZ was significantly and independently associated with higher long-term risk of stroke and CHD. In pooled analyses, compared with individuals with no history of HZ, the multivariable-adjusted hazard ratios (95% CIs) for stroke were 1.05 (0.88-1.25) among those with 1 to 4 years since HZ, 1.38 (1.10-1.74) for among those with 5 to 8 years since HZ, 1.28 (1.03-1.59) among those with for 9 to 12 years since HZ, and 1.19 (0.90-1.56) among those with ≥13 years since HZ. For CHD, the corresponding multivariable-adjusted hazard ratios (95% CIs) were 1.13 (1.01-1.27) for 1 to 4 years, 1.16 (1.02-1.32) for 5 to 8 years, 1.25 (1.07-1.46) for 9 to 12 years, and 1.00 (0.83-1.21) for ≥13 years. Conclusions HZ is associated with higher long-term risk of a major cardiovascular event. These findings suggest there are long-term implications of HZ and underscore the importance of prevention.

Diagnostic and therapeutic approach to adult central nervous system vasculitis

The clinical manifestations of central nervous system (CNS) vasculitis are highly variable. In the absence of a positive CNS biopsy, CNS vasculitis is particularly suspected when markers of both vascular disease and inflammation are present. To facilitate the clinical and therapeutic approach to this rare condition, CNS vasculitis can be classified according to the size of the involved vessels. Vascular imaging is used to identify medium vessel disease. Small vessel disease can only be diagnosed with a CNS biopsy. Medium vessel vasculitis usually presents with focal neurological signs, while small vessel vasculitis more often leads to cognitive deficits, altered level of consciousness and seizures. Markers of CNS inflammation include cerebrospinal fluid pleocytosis or elevated protein levels, and vessel wall, parenchymal or leptomeningeal enhancement. The broad range of differential diagnoses of CNS vasculitis can be narrowed based on the disease subtype. Common mimickers of medium vessel vasculitis include intracranial atherosclerosis and reversible cerebral vasoconstriction syndrome. The diagnostic workup aims to answer two questions: is the neurological presentation secondary to a vasculitic process, and if so, is the vasculitis primary (i.e., primary angiitis of the CNS) or secondary (e.g., to a systemic vasculitis, connective tissue disorder, infection, malignancy or drug use)? In primary angiitis of the CNS, glucocorticoids and cyclophosphamide are most often used for induction therapy, but rituximab may be an alternative. Based on the available evidence, all patients should receive maintenance immunosuppression. A multidisciplinary approach is necessary to ensure an accurate and timely diagnosis and to improve outcomes for patients with this potentially devastating condition.

Why Would a Child Have a Stroke?

Identifying the etiology of childhood arterial ischemic stroke helps prevent stroke recurrence. In addition, stroke may herald a serious underlying condition requiring treatment, such as acquired heart disease, malignancy, or autoimmune disorder. Evidence-based guidelines exist for adults to identify and treat common risk factors for primary and secondary stroke, including hypertension, diabetes, elevated lipids, atrial fibrillation, and sleep apnea, which are rarely relevant in children. However, guidelines do not exist in pediatrics. Identifying the cause of childhood stroke may be straightforward or may require extensive clinical and neuroimaging expertise, serial evaluations, and reassessment based on the evolving clinical picture. Risk factors may be present but not necessarily causative, or not causative until a triggering event such as infection or anemia occurs. Herein, we describe strategies to determine stroke etiology, including challenges and potential pitfalls.

The Role of Infection and Inflammation in the Pathogenesis of Pediatric Arterial Ischemic Stroke

Infections play an important role in the pathogenesis of acute ischemic stroke (AIS) in neonates and children. In neonates, chorioamnionitis or intrauterine inflammation has been implicated as a common risk factor for AIS. In infants and children, recent investigations demonstrated that even minor childhood infections are associated with subsequent increased risk for AIS. Post-infectious inflammatory mechanisms following infections with herpesviruses may lead to focal cerebral arteriopathy (FCA), one of the most common causes of AIS in a previously healthy child. Other agents such as parvovirus B19, dengue virus, and SARS-CoV-2 have recently been implicated as other potential triggers. Infections are compelling treatable stroke risk factors, with available therapies for both pathogens and downstream inflammatory effects. However, infections are common in childhood, while stroke is uncommon. The ongoing VIPS II (Vascular effects of Infection in Pediatric Stroke) study aims to identify the array of pathogens that may lead to childhood AIS and whether either unusual strains or unusual combinations of pathogens explain this paradox. Immune modulation with corticosteroids for FCA is another active area of research, with European and U.S. trials launching soon. The results of these new pediatric stroke studies combined with findings emerging from the larger field of immune-mediated post-infectious diseases will likely lead to new approaches to the prevention and treatment of pediatric stroke. This review highlights recent developments from both clinical and animal model research enhancing our understanding of this relationship between infection, inflammation, and stroke in neonates and children.

Spectrum of Large- and Medium-Vessel Vasculitis in Adults: Neoplastic, Infectious, Drug-Induced, Autoinflammatory, and Primary Immunodeficiency Diseases

PURPOSE OF REVIEW

To provide a comprehensive review of drugs and neoplastic, infectious, autoinflammatory, and immunodeficiency diseases causing medium- to large-vessel vasculitis in adults with emphasis on information essential for the initial diagnostic process.

RECENT FINDINGS

Entities with medium- to large-vessel vasculitis as clinical manifestations have been described recently (e.g., adenosine deaminase-2 deficiency, VEXAS-Syndrome), and vasculitis in established autoinflammatory or immunodeficiency diseases is increasingly being identified. In the diagnostic process of medium- to large-vessel vasculitis in adults, a large variety of rare diseases should be included in the differential diagnosis, especially if diagnosis is made without histologic confirmation and in younger patients. Although these disorders should be considered, they will undoubtedly remain rare in daily practice.

Aseptic Meningitis after Amenamevir Treatment for Herpes Zoster in the First Branch of the Trigeminal Nerve

Amenamevir has been approved for the treatment of herpes zoster (HZ); however, its therapeutic efficacy against central nervous system (CNS) infection may be insufficient due to its low spinal fluid permeability. We herein report a case of aseptic meningitis in a 91-year-old Japanese man treated with amenamevir for HZ in the trigeminal nerve region. Several cases of CNS infection have been reported in patients receiving amenamevir treatment for HZ. Patients with CNS complications often have skin rashes near the trigeminal region. Thus, we should be alert for signs of CNS infection when administering amenamevir to patients with such rashes.

Varicella zoster-associated progressive lower cranial and upper cervical polyneuropathy: a case report

Background

Multiple cranial neuropathies carry a wide range of differential diagnoses, and when combined with cerebrospinal fluid monocytosis they often suggest an infective etiology. Reactivation of varicella zoster virus has been associated with a wide range of neurological complications. Among the cranial nerves, the upper cranial nerves (trigeminal and facial nerves) are more commonly affected; there have been some reports of lower cranial polyneuropathies resulting from varicella zoster virus reactivation. However, polyneuropathy involving both the cranial and cervical nerves is rarely reported.

Case presentation

This report highlights the case of a 64-year-old Chinese man presenting with an acute, severe dysphagia and dysphonia secondary to herpes zoster-associated progressive polyneuropathy involving the lower cranial and upper cervical nerves, without any mucocutaneous manifestations.

Conclusions

To our knowledge, this is the first case of varicella zoster virus-associated cranial and cervical polyneuropathy in the literature. The report also highlights the poor sensitivity of varicella zoster virus DNA detection by polymerase chain reaction in the cerebrospinal fluid, and proposes that serology be routinely performed in such polymerase chain reaction-negative cases without a clear diagnosis.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13256-022-03484-7.

Cross-Sectional Retrospective Study to Identify Clinical and Radiographic Features Associated With VZV Reactivation in Cryptogenic Stroke Patients With CSF Testing

BACKGROUND AND PURPOSE

A large proportion of ischemic stroke patients lack a definitive stroke etiology despite extensive diagnostic testing. Varicella-Zoster Virus (VZV) can directly invade blood vessels causing vasculitis and may be associated with cryptogenic stroke (CS).

METHODS

We conducted a retrospective cross-sectional study of CS patients tested for VZV. The following were considered evidence of VZV reactivation (VZV+): positive CSF VZV PCR, anti-VZV IgM in CSF, or anti-VZV IgG CSF/serum ratio of 1:10 or higher. We describe the cohort, report VZV+ proportion with 95% confidence intervals (CI) determined with the Wald method, and compare patient groups using standard statistical tests.

RESULTS

A total of 72 CS patients met full study inclusion criteria. Most of the patients were <65 years old, had few traditional vascular risk factors, and had multifocal infarcts. Mean age was 49 years (SD ±13) and 47% were women. A total of 14 patients (19.4%; CI: 11.4-30.8%) had evidence of CNS VZV reactivation. There was no difference in evaluated demographic or radiographic features between those with versus without evidence of VZV reactivation. History of ischemic stroke in the past year (11/14 vs 25/43, P<.05) and hypertension (13/14 vs 35/58 and P<.05) were associated with VZV+.

CONCLUSION

We found a high proportion of CNS VZV reactivation in a cross-sectional cohort of CS patients selected for CSF testing. Testing for VZV might be reasonable in CS patients who are young, have multifocal infarcts, or had an ischemic stroke within the past year, but additional research is needed.

New Insights into the Pathogenesis of Giant Cell Arteritis: Mechanisms Involved in Maintaining Vascular Inflammation

The giant cell arteritis (GCA) pathophysiology is complex and multifactorial, involving a predisposing genetic background, the role of immune aging and the activation of vascular dendritic cells by an unknown trigger. Once activated, dendritic cells recruit CD4 T cells and induce their activation, proliferation and polarization into Th1 and Th17, which produce interferon-gamma (IFN-γ) and interleukin-17 (IL-17), respectively. IFN-γ triggers the production of chemokines by vascular smooth muscle cells, which leads to the recruitment of additional CD4 and CD8 T cells and also monocytes that differentiate into macrophages. Recent data have shown that IL-17, IFN-γ and GM-CSF induce the differentiation of macrophage subpopulations, which play a role in the destruction of the arterial wall, in neoangiogenesis or intimal hyperplasia. Under the influence of different mediators, mainly endothelin-1 and PDGF, vascular smooth muscle cells migrate to the intima, proliferate and change their phenotype to become myofibroblasts that further proliferate and produce extracellular matrix proteins, increasing the vascular stenosis. In addition, several defects in the immune regulatory mechanisms probably contribute to chronic vascular inflammation in GCA: a defect in the PD-1/PD-L1 pathway, a quantitative and qualitative Treg deficiency, the implication of resident cells, the role of GM-CSF and IL-6, the implication of the NOTCH pathway and the role of mucosal‑associated invariant T cells and tissue‑resident memory T cells.

Recovery of intracranial stenoses in varicella zoster virus vasculitis after long-term treatment with valacyclovir and prednisolone

BACKGROUND AND PURPOSE

Optimal treatment of intracranial stenoses in varicella zoster virus (VZV)-associated vasculitis is unknown. This study aims to evaluate the merits and potential pitfalls of a specific therapeutic strategy, initially proposed by Don Gilden in 2015.

METHODS

We describe three patients with intracranial stenoses caused by VZV vasculitis successfully treated by a long-term combination of valacyclovir and prednisolone.

RESULTS

All three patients were young men suffering from stroke. Only one reported a first contact to VZV in adulthood. All three presented stenoses in the intracranial part of the internal carotid artery or the proximal segments of the middle cerebral artery as well as an elevated cell count and positive VZV antibody index in cerebrospinal fluid. They received a combination therapy regimen with prednisone and valacyclovir about a minimum of one year. Intracranial stenoses improved markedly in one and almost resolved completely in the other two patients. Side effects of corticosteroid treatment occurred in two patients.

CONCLUSIONS

Long-term combination treatment with prednisone and valacyclovir proved to be effective in three young men suffering from intracranial stenosis due to VZV vasculitis.

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.

Atypical Imaging Findings in “Central Nervous System Varicella Zoster Virus Vasculopathy Sine Herpete”

Varicella-zoster virus (VZV) infection is notorious for central nervous system involvement, the spectrum of which encompasses vasculopathic manifestations as well. Central nervous system VZV vasculopathy (CVV) most commonly manifests as ischemic strokes or TIA, even though other less common modes of presentation are also well documented in the literature. The pathophysiological mechanism is primarily attributed to active virus infection in the blood vessels secondary to decline in varicella-specific cell-mediated immunity. More than one-third of those with CVV do not have preceding skin lesions of zoster. Hence, a high index of clinical suspicion should be entertained in the appropriate clinical scenario. We hereby describe the case of a 40-year-old lady with systemic lupus erythematosus on long-term oral steroids who presented with acute ischemic stroke involving the right PCA territory, with asymptomatic chronic infarcts in the left MCA. Further evaluation revealed concentric vessel enhancement involving right PCA on high-resolution MR vessel wall imaging with the “Moya-Moya” phenomenon on the left supraclinoid ICA/MCA segment. CSF showed mononuclear pleocytosis with a hemorrhagic component, along with positive VZV DNA PCR. A diagnosis of “CNS VZV Vasculopathy sine herpete” was made and the patient was initiated on appropriate management.

Varicella-zoster virus reactivation is frequently detected in HIV-infected individuals presenting with stroke

Infections are an underappreciated cause of stroke, particularly in young and immunocompromised individuals. Varicella-zoster virus (VZV) reactivation, particularly ophthalmic zoster, has been linked to increased risk of stroke but diagnosing VZV-associated cerebral vasculopathy is challenging as neither a recent Zoster rash, nor detectable levels of VZV DNA are universally present at stroke presentation. Detection of VZV IgG in cerebrospinal fluid (CSF-VZVG) presents a promising alternative, but requires evaluation of individual blood-CSF dynamics, particularly in the setting of chronic inflammatory states such as HIV infection. Consequently, its use has not been broadly adopted as simple diagnostic algorithms are not available. In this study looking at young adults presenting with acute stroke, we used an algorithm that includes testing for both VZV nucleic acids and CSF-VZVG which was corrected for blood-CSF barrier dynamics and poly-specific immune activation. We found that 13 of 35 (37%), including 7 with a positive CSF VZV PCR, young HIV-infected adults presenting with stroke, 3 of 34 (9%) young HIV-uninfected adults presenting with stroke and 1 of 18 (6%) HIV-infected non-stroke controls demonstrated evidence of central nervous system reactivation of VZV. This article is protected by copyright. All rights reserved.

Neurological complications of varicella zoster virus reactivation: Prognosis, diagnosis, and treatment of 72 patients with positive PCR in the cerebrospinal fluid

BACKGROUND

VZV infection can involve every level of the neurologic system: from the central nervous system (CNS) to the peripheral nervous system (PNS), including aseptic meningitis. Prognosis seems to differ between these neurological involvements. Prognostic factors remain unknown.

METHODS

This is a retrospective multicenter study including all patients with a positive VZV polymerase chain reaction (PCR) in the cerebrospinal fluid (CSF) from eight centers in Paris (France) between 2011 and 2018. Unfavorable outcome was defined as mortality linked to VZV or incomplete recovery. Modified Rankin Scale (mRS) evaluated disability before and after the infection, with the difference designated as Rankin Delta.

RESULTS

Seventy-two patients were included (53% male, median age 51 years, median mRS 0). Immunosuppression was reported in 42%. The clinical spectrum included 26 cases of meningitis, 27 instances of CNS involvement, 16 of PNS involvement, and 3 isolated replications (positive PCR but no criteria for neurological complications from VZV). Antiviral treatment was administered to 69 patients (96%). Sixty-two patients completed follow-up. Death linked to VZV occurred in eight cases. Unfavorable outcome (UO) occurred in 60% and was significantly associated with a higher prior mRS (Odd-ratio (OR) 3.1 [1.4-8.8] p = .012) and the presence of PNS or CNS manifestations (OR 22 [4-181] p = .001, OR 6.2 [1.3-33] p = .03, respectively, compared to meningitis). In the CSF, higher protein level (p < .0001) was also significantly associated with a higher Rankin Delta.

CONCLUSIONS

Neurological complications of VZV with evidence of CSF viral replication are heterogeneous: aseptic meningitis has a good prognosis, whereas presence of CNS and PNS involvement is associated with a higher risk of mortality and of sequelae, respectively.

Metagenomic Next-Generation Sequencing vs. Traditional Microbiological Tests for Diagnosing Varicella-Zoster Virus Central Nervous System Infection

Background

Unbiased metagenomic next-generation sequencing (mNGS) detects pathogens in a target-independent manner. It is not well-understood whether mNGS has comparable sensitivity to target-dependent nucleic acid test for pathogen identification.

Methods

This study included 31 patients with chickenpox and neurological symptoms for screening of possible varicella-zoster virus (VZV) central nervous system (CNS) infection. Microbiological diagnosing of VZV cerebrospinal fluid (CSF) infection was performed on stored CSF samples using mNGS, quantitative and qualitative VZV-specific PCR assays, and VZV IgM antibodies test.

Results

The median age was 30.0 [interquartile range (IQR), 24.3–33.3] years. 51.6% of the patients were men. About 80.6% of the patients had normal CSF white blood cell counts (≤ 5 × 10⁶/L). VZV IgM antibodies presented in 16.1% of the CSF samples, and nucleic acids were detectable in 16.1 and 9.7% using two different VZV-specific real-time PCR protocols. Intriguingly, maximal identification of VZV elements was achieved by CSF mNGS (p = 0.001 and p = 007; compared with qualitative PCR and VZV IgM antibody test, respectively), with sequence reads of VZV being reported in 51.6% (16/31) of the CSF samples. All VZV PCR positive samples were positive when analyzed by mNGS. Of note, human betaherpesvirus 6A with clinical significance was unexpectedly detected in one CSF sample.

Conclusions

Our study suggests that CSF mNGS may have higher sensitivity for VZV detection than CSF VZV PCR and antibody tests, and has the advantage of identifying unexpected pathogens.

Temporal Artery Vascular Diseases

In the presence of temporal arteritis, clinicians often refer to the diagnosis of giant cell arteritis (GCA). However, differential diagnoses should also be evoked because other types of vascular diseases, vasculitis or not, may affect the temporal artery. Among vasculitis, Anti-neutrophil cytoplasmic antibodies (ANCA)-associated vasculitis is probably the most common, and typically affects the peri-adventitial small vessel of the temporal artery and sometimes mimics giant cell arteritis, however, other symptoms are frequently associated and more specific of ANCA-associated vasculitis prompt a search for ANCA. The Immunoglobulin G4-related disease (IgG4-RD) can cause temporal arteritis as well. Some infections can also affect the temporal artery, primarily an infection caused by the varicella-zoster virus (VZV), which has an arterial tropism that may play a role in triggering giant cell arteritis. Drugs, mainly checkpoint inhibitors that are used to treat cancer, can also trigger giant cell arteritis. Furthermore, the temporal artery can be affected by diseases other than vasculitis such as atherosclerosis, calcyphilaxis, aneurysm, or arteriovenous fistula. In this review, these different diseases affecting the temporal artery are described.

Cerebrovascular Complications After Adult-Onset Varicella-Zoster Virus Encephalitis in the Central Nervous System: A Literature Review

BACKGROUND

Cerebrovascular complications after adult-onset varicella-zoster virus (VZV) encephalitis have been increasingly recognized. The aim of this study was to analyze clinical and neuroimaging findings, treatment and outcome of these patients.

METHODS

Literature review from January 2000 to December 2019. We searched for studies published in PubMed, Embase and Chinese Biomedical Literature Database. Clinical symptoms, neuroimaging findings, treatment and outcome were evaluated.

RESULTS

We analyzed 31 articles with a total of adult-onset 34 cases, including 25 cases of ischemic stroke, 6 of intracerebral hemorrhage and 3 with venous sinus thrombosis. Ischemic stroke was the major complication after VZV encephalitis accounting of 73.35%. There were more males than females in ischemia or venous sinus thrombosis groups. The middle-aged was prone to cerebral infarction, the elderly was for cerebral hemorrhage, and the young was for venous sinus thrombosis. Cognitive impairment was the most common symptom either in the ischemic group or hemorrhagic group. The lesions of VZV-associated cerebral infarction or hemorrhage were multifocal and mostly involved in the parietal lobe, followed by frontal or temporal lobes. Venous sinus thrombosis was common in the transverse sinus. Multiple stenosis of the anterior and posterior circulation vessels was found. A 60.87% of the patients with antiviral treatment in the ischemic group had favorable prognosis. All patients with anticoagulant therapy in venous sinus thrombosis group improved well; however, 60% of the patients with intracerebral hemorrhage had a poor prognosis or died.

CONCLUSION

Ischemic stroke was the majority of cerebrovascular complications after VZV encephalitis, which mainly occurred in middle-aged men. The lesions of VZV-associated cerebral infarction or hemorrhage were multifocal and did not accord with the characteristics of cerebrovascular diseases induced by atherosclerosis. The patients with venous sinus thrombosis had a relatively good prognosis. When the patient represents with some neurological symptoms about one month after VZV encephalitis, and multiple lesions probably induced by vasculitis are showed in neuroimaging, cerebrovascular complications related to VZV infection should be considered.

Detection of human herpesviruses in cerebrospinal fluids collected from patients suspected of neuroinfectious diseases

The full spectrum of human herpesviruses (HHV)-associated neuroinfectious diseases in immunocompetent adults remains unclear. Hence, we sought to elucidate the epidemiology and clinical features of these diseases. The study subjects were patients over 16 years old suspected of neuroinfectious diseases who underwent spinal tap performed by neurologists in our university hospital between April 2013 and March 2018. The presence of seven HHV DNAs in cerebrospinal fluid (CSF) was determined by real-time PCR. HHV DNAs were detected in 33 (10.2%) of the 322 patients. The most frequently detected herpesvirus was varicella zoster virus (VZV) (19 patients), followed by HHV-6 (four patients), herpes simplex virus (HSV)-1 (three patients), HSV-2 (three patients), and Epstein-Barr virus (two patients). HHV DNAs were detected in CSF collected from patients with various neuroinfectious diseases, including myelitis, peripheral neuritis, encephalitis, and meningitis. All patients with HSV-1 DNA had encephalitis, whereas all patients with HSV-2 DNA had meningitis. Eleven of the 19 patients with VZV DNA had meningitis. Patients with VZV-associated encephalitis (median age, 80 years) were significantly older than non-encephalitis patients (median age, 60.5 years) (P = 0.046). Although post-herpetic neuralgia was observed in seven (54%) of the 13 patients with VZV and without encephalitis, no such neurological sequela was observed in the four encephalitis patients. In conclusion, HHVs were associated with approximately 10% of neuroinfectious diseases in this cohort. VZV was the most common pathogen, probably due to the large number of VZV meningitis patients. In addition, patients with VZV-associated meningitis were significantly younger than patients with VZV-associated encephalitis.

High-resolution intracranial vessel wall imaging in cerebral viral infections evaluations

Purpose

Vascular complications can be seen in various viral CNS infections. Variable neuro-imaging findings have been described in the literature elucidating the parenchymal changes with vascular involvement. Vessel wall imaging (VWI) can help to detect these vascular involvements. We aimed to describe the role and usefulness of VWI in the evaluation of various viral CNS infections.

Methods

In this prospective study, we included 15 cases of various diagnosed viral CNS infections (varicella, HIV encephalopathy, HSV encephalitis, Japanese encephalitis, dengue, COVID-19). VWI and time-of-flight MR angiography (TOF MRA) were included in imaging protocol. All cases were evaluated for the presence of cerebral parenchymal changes, vascular enhancement, and vascular stenosis.

Results

We found infarctions in all 5 cases of varicella, 1 case of HIV encephalopathy, and 1 case of COVID-19 encephalopathy. All these cases also showed vascular enhancement and stenosis on VWI. The rest of the cases, including 1 case of HIV encephalopathy, 3 cases of herpes encephalitis, 2 cases of dengue, and 2 cases of Japanese encephalitis did not have any vascular complication, and also did not show vascular enhancement or stenosis.

Conclusion

VWI can be useful in the detection of vascular involvement in various viral infections of CNS which show a relatively higher cerebrovascular complication rate like varicella, HIV encephalopathy, and COVID-19. However, VWI may not be useful in the routine evaluation of other viral infections like herpes, dengue, and Japanese encephalitis, which have a very low rate of cerebrovascular complication rate.

Approach to Neurologic Complications in the Immunocompromised Patient

Neurologic complications are common in immunocompromised patients, including those with advanced human immunodeficiency virus, transplant recipients, and patients on immunomodulatory medications. In addition to the standard differential diagnosis, specific pathogens and other conditions unique to the immunocompromised state should be considered in the evaluation of neurologic complaints in this patient population. A thorough understanding of these considerations is critical to the inpatient neurologist in contemporary practice, as increasing numbers of patients are exposed to immunomodulatory therapies. In this review, we provide a chief complaint-based approach to the clinical presentations and diagnosis of both infectious and noninfectious complications particular to immunocompromised patients.

Clinical use of steroids in viral central nervous system (CNS) infections: three challenging cases

The role of adjunctive corticosteroids in reducing morbidity and mortality of viral CNS infections remains poorly defined. Clinicians are often left in a quagmire regarding steroid use in complex and rapidly evolving viral CNS infections. Limited studies have explored the underlying mechanisms behind the potential benefit of steroids. Here, we describe steroid use in three cases of viral CNS disease: varicella zoster virus (VZV), Powassan virus, and influenza A-associated acute necrotizing encephalopathy.

[A case of neuro-Behçet's disease triggered by herpes zoster-associated uveitis]

A 69-year-old man was admitted for persistent fever, arthralgia, and visual impairment. Physical examination demonstrated bilateral uveitis and recurrent aphthous stomatitis. The PCR analysis of the aqueous humor of the anterior chamber was positive for the Varicella-zoster virus (VZV). Although no neurological defect was evident, the cerebrospinal fluid contained elevated monocytes but was negative for VZV-PCR. Brain MRI revealed Gd-enhanced lesions in the subcortical white matter, basal ganglia, and cerebellum. With his positive HLAB51, he was diagnosed with neuro-Behcet's disease (NBD) and was successfully treated with high-dose prednisolone. Although the pathogenesis of Behcet's disease is still unknown, the involvement of viral infection is reported. The present case implies that NBD could be triggered by herpes zoster virus associate-uveitis; the accumulation of such cases would help clarify the pathogenesis of Behcet's disease.

Current Clinical Applications of Intracranial Vessel Wall MR Imaging

Intracranial vessel wall MR imaging (VWI) is increasingly being used as a valuable adjunct to conventional angiographic imaging techniques. This article will provide an updated review on intracranial VWI protocols and image interpretation. We review VWI technical considerations, describe common VWI imaging features of different intracranial vasculopathies and show illustrative cases. We review the role of VWI for differentiating among steno-occlusive vasculopathies, such as intracranial atherosclerotic plaque, dissections and Moyamoya disease. We also highlight how VWI may be used for the diagnostic work-up and surveillance of patients with vasculitis of the central nervous system and cerebral aneurysms.

Neurologic Infections in Patients on Immunomodulatory and Immunosuppressive Therapies

PURPOSE OF REVIEW

Both broadly immunosuppressive medications and selective immunomodulatory agents that act on particular components of the immune system are increasingly used in the treatment of neurologic and non-neurologic diseases. These therapies predispose patients to particular infections, some of which may affect the nervous system. Therefore, familiarity with the clinical and radiologic features of neurologic infections associated with specific immunomodulatory therapies is of importance for the practicing neurologist. This article reviews these neuroinfectious conditions, as well as other neurologic complications unique to transplant recipients and other patients who are immunocompromised.

RECENT FINDINGS

Diagnosis of infectious pathogens in patients who are immunocompromised may be particularly challenging because a decreased immune response can lead to atypical imaging or laboratory findings. Next-generation sequencing and other novel diagnostic modalities may improve the rate of early identification of neurologic infections in patients who are immunocompromised and ultimately ameliorate outcomes in this vulnerable population.

SUMMARY

A broad range of bacterial, viral, fungal, and parasitic infections of the nervous system can complicate solid organ and hematopoietic cell transplantation as well as other forms of immunocompromise. In addition to neurologic infections, such patients are at risk of neurotoxic and neuroinflammatory complications related to immunomodulatory and immunosuppressive therapies. Early recognition of infectious and noninfectious complications of immunocompromise is essential to guide appropriate treatment, which can include antimicrobial therapy and, in some cases, withdrawal of the predisposing medication with a transition to an alternative regimen.

Encephalitis and Brain Abscess

PURPOSE OF REVIEW

This article reviews infections of the brain parenchyma and includes an overview of the epidemiology, pathogenesis, diagnostic approach, and management of infectious encephalitis and brain abscess.

RECENT FINDINGS

The epidemiology of infectious encephalitis and brain abscess has changed in recent years. Vaccination has reduced the incidence of certain viruses associated with encephalitis, while a decrease in fulminant otogenic infections has led to fewer brain abscesses associated with otitis media. However, changes in climate and human population density and distribution have enabled the emergence of newer pathogens and expanded the geographic range of others, and greater adoption of intensive immunosuppressive regimens for autoimmune conditions has increased the risk of opportunistic infections of the brain. The widespread use of early neuroimaging, along with improved diagnostic methodologies for pathogen detection, newer antimicrobial therapies with better brain penetration, and less invasive neurosurgical techniques, has resulted in better outcomes for patients with infectious encephalitis and brain abscess. Novel technologies including metagenomic next-generation sequencing are increasingly being applied to these conditions in an effort to improve diagnosis. Nevertheless, both infectious encephalitis and brain abscess continue to be associated with substantial mortality.

SUMMARY

Infectious encephalitis and brain abscess can present as neurologic emergencies and require rapid assessment, thorough and appropriate diagnostic testing, and early initiation of empiric therapies directed against infectious agents. Close clinical follow-up, proper interpretation of diagnostic results, and appropriate tailoring of therapeutic agents are essential to optimizing outcomes. Diagnosis and management of parenchymal brain infections are complex and often best achieved with a multidisciplinary care team involving neurologists, neurosurgeons, neuroradiologists, infectious disease physicians, and pathologists.

Infection, Infectious Agents and Vascular Disease

BACKGROUND

Infectious agents may be involved in the pathogenesis of vascular disease and related complications. The aim of this review is to analyze the most relevant information on the common infections related to vascular disease, discussing the main pathophysiological mechanisms.

METHODS

In the current review, the most important evidence on the issue of infections and vascular disease is searched on Medline, Scopus, and ScienceDirect database.

RESULTS

Among infectious agents, herpesviruses, parvovirus B19, hepatitis viruses, human immunodeficiency virus, severe acute respiratory syndrome coronavirus 2, treponema pallidum, mycobacterium tuberculosis, pseudomonas aeruginosa, staphylococcus aureus, and candida albicans seem to particularly related to vascular disease.

CONCLUSION

Infectious agents may affect vessel's homeostasis and functionality, both on the arterial and venous side, by means of several pathophysiological mechanisms such as dysregulation in vasomotor function, thromboembolic complications, initiation and progression of atherosclerosis, alteration of perivascular adipose tissue, recruiting inflammatory cells and molecules.

Arteriopathy in pediatric stroke: an underestimated clinical entity

BACKGROUND

Pediatric arterial ischemic stroke (AIS), which was thought to be a rare disorder, is being increasingly recognized as an important cause of neurological morbidity, thanks to new advances in neuroimaging.

OBJECTIVE

The aim of this study was to review the main etiologies of stroke due to arteriopathy in children.

METHODS

Using a series of cases from our institution, we addressed its epidemiological aspects, physiopathology, imaging findings from CT, MR angiography, MR conventional sequences and MR DWI, and nuclear medicine findings.

RESULTS

Through discussion of the most recent classification for childhood AIS (Childhood AIS Standardized Classification and Diagnostic Evaluation, CASCADE), we propose a modified classification based on the anatomical site of disease, which includes vasculitis, varicella, arterial dissection, moyamoya, fibromuscular dysplasia, Takayasu's arteritis and genetic causes (such as ACTA-2 mutation, PHACE syndrome and ADA-2 deficiency). We have detailed each of these separately. Conclusions: Prompt recognition of AIS and thorough investigation for potential risk factors are crucial for a better outcome. In this scenario, neurovascular imaging plays an important role in diagnosing AIS and identifying children at high risk of recurrent stroke.

Late neurosyphilis and VZV meningoencephalitis coinfection

The incidence of syphilis has increasing recently, largely attributable to improved screening that may result in the diagnosis of chronic untreated infections. These patients can develop severe or subtle neurologic symptoms that can be missed and, therefore, detected accidentally while a patient is evaluated for other mimicking neurological infections. A 58-year-old man with diabetes presented with 2 days of aphasia, headache, chills and confusion. He had an MRI brain with evidence of a prior cerebrovascular accident. Subsequently, he developed a fever and thoracic dermatomal rash consistent with herpes zoster. A lumbar puncture was performed, and cerebrospinal fluid analysis revealed a lymphocytic pleocytosis, a reactive Venereal Disease Research Laboratory test and positive varicella-zoster virus (VZV) PCR. He was suspected to have both late neurosyphilis and acute meningoencephalitis from VZV. This paper will discuss how to approach the diagnosis of late neurosyphilis and possible associations with herpesvirus central nervous system infections.

Acute Stroke Caused by Progressive Intracranial Artery Stenosis Due to Varicella Zoster Virus Vasculopathy after Chemotherapy for Malignant Lymphoma

Decreased cell-mediated immunity can reactivate Varicella zoster virus (VZV), which can lead to various neurological complications, including vasculopathy. We herein report the case of a patient with acute stroke with progressive internal carotid artery stenosis due to VZV vasculopathy after chemotherapy for malignant lymphoma. Treatment for VZV vasculopathy improved the stenosis and prevented recurrent stroke. VZV vasculopathy is an important treatable cause of stroke in immunosuppressed patients.

Pulsed Radiofrequency of the Trigeminal Ganglion for Treating Postherpetic Neuralgia of the Ophthalmic Branch

Postherpetic neuralgia (PHN) is a painful, long-lasting condition as a consequence of nerve damage resulting from a herpes zoster infection. Although there are many different treatments available to reduce pain duration and severity, PHN is often refractory to them and no single therapy shows an effective cure for all cases of PHN, especially for those involving the ophthalmic branch of the trigeminal nerve. Pulsed radiofrequency (PRF) is a minimally invasive procedure for pain treatment that has been practiced over the past decade. However, its clinical efficacy and safety for treating PHN involving the ophthalmic branch of the trigeminal nerve have not been evaluated. Objective. This study aimed to evaluate the efficacy and safety of PRF for treating PHN involving the ophthalmic branch of the trigeminal ganglion. Study Design. An observational study. Setting. All patients received PRF of the ophthalmic branch of the trigeminal nerve, pain intensity was assessed by a visual analogue scale (VAS), and complications before and after PRF stimulation were noted. Methods. Thirty-two patients with PHN of the ophthalmic branch were treated by PRF of the ophthalmic branch with controlled temperature at 42°C for 8 min. Pain relief, corneal reflex, sleep quality, and satisfaction were assessed for all patients. Results. Thirty out of 32 patients (93.75%) reported significant pain reduction after PRF treatment. Twenty-eight of them (87.5%) were satisfied with their sleep and obtained a pain score lower than 3 following the procedure. Only two patients had a recurrence of the severe burning pain and returned to the hospital for other medical therapies 2 weeks after the PRF procedure. No patient lost the corneal reflex. Limitations. This study is an observational study and a nonprospective trial with a short-term follow-up period. Conclusion. PRF of the trigeminal ganglion of the ophthalmic branch can significantly reduce pain sensation and improve sleep quality and satisfaction for PHN of the ophthalmic branch.

Expanding the clinical and neuroimaging features of post-varicella arteriopathy of childhood

OBJECTIVE

Post-varicella arterial ischemic stroke (AIS) is considered an uncommon cause of pediatric stroke that is considered a self-limiting, monophasic disease. However, in a subset of patients, disease recurs; the prevalence of vasculopathy or AIS recurrence, severity of clinical outcomes, and standardized therapies have not been well characterized. Herein, we determined the clinical-neuroradiological features, long-term evolution, and relationship between acute phase treatment and vasculopathy recurrence in a pediatric population with post-varicella AIS.

METHODS

Clinical, laboratory, and neuroradiological features of 22 children with post-varicella AIS between 2010 and 2019 (16 males, mean age at stroke 4 years, range 1.7-10) were reviewed. Statistical analyses were performed using χ² and Fisher exact tests.

RESULTS

Of the 22 cases, mean time from varicella to stroke was 4.5 months with 3 cases presenting more than 12 months after rash; 21 (95%) were not vaccinated for varicella; 3 (13.6%) had posterior circulation involvement; and 5 (22.7%) had AIS or vasculopathy recurrence, of which 4 recurred 6.1 months to 2.8 years after initial clinical onset. Recurrence was associated with lack of antiviral treatment during the first episode (p = 0.02).

CONCLUSIONS

Post-varicella AIS can occur months after rash making diagnosis challenging. Because recurrent vasculopathy was seen predominantly in cases not treated with antiviral therapy during initial presentation, it is important to rapidly diagnose post-varicella AIS through clinical criteria and/or virological testing then treat with antivirals to prevent recurrence.

Infectious Myelopathies

In the setting of both globalization and increasing use of immunosuppressive therapy, infectious myelopathies are an important cause of morbidity worldwide. Clinical spinal cord syndromes related to infection are varied, including transverse myelitis, acute flaccid paralysis related to anterior horn cell involvement, spinal cord compression, chronic spastic paraparesis, and myeloradiculitis. Causative pathogens include viruses, parasites, pyogenic and atypical bacteria, and fungi. The epidemiology, clinical characteristics, diagnosis, and treatment of selected organisms will be discussed in this article.

Implementation and Rationale for a Unified Clinical and Imaging Protocol for Evaluation and Treatment of Moyamoya Angiopathy: A Single Institutional Experience

Moyamoya disease (MMD) is a complex and incompletely-understood cerebrovascular pathological entity that requires thorough clinical and imaging evaluation. Moyamoya is rare, thereby making the establishment of an effective, thorough and interdisciplinary patient evaluation protocol challenging, even within specialized referral centers. Nevertheless, implementation of such a protocol is crucial in order to provide the best possible evaluation and treatment for MMD patients. Here, we describe our institution's implementation of, rationale for, and experience with a comprehensive multidisciplinary collaboration and evaluation strategy for adult patients with moyamoya. This evaluation course consists of, first of all, a thorough clinical and laboratory evaluation with a vascular neurologist. This is followed by a comprehensive imaging assessment which evaluates angiographic and parenchymal features, in addition to cerebrovascular functionality. Finally, appropriate referrals are made to consulting services as indicated, which includes vascular neurosurgery. These steps are described in detail herein.

MRI of Emergent Intracranial Infections and Their Complications

Acute intracranial infections of the central nervous system and skull base are uncommon but time sensitive diagnoses that may present to the emergency department. As symptoms are frequently nonspecific or lack typical features of an infectious process, a high index of suspicion is required to confidently make the diagnosis, and imaging may not only serve as the first clue to an intracranial infection, but is often necessary to completely characterize the disease process and exclude any confounding conditions. Although computed tomography is typically the initial imaging modality for many of these patients, magnetic resonance imaging offers greater sensitivity and specificity in diagnosing intracranial infections, characterizing the full extent of infection, and identifying potential complications. The aim of this article is to serve as a review of the typical and most important imaging manifestations of these infections that can be encountered in the emergent setting.

Acute Viral Illnesses and Ischemic Stroke: Pathophysiological Considerations in the Era of the COVID-19 Pandemic

The severe acute respiratory syndrome coronavirus 2 or coronavirus disease 2019 (COVID-19) pandemic has raised concerns about the correlation with this viral illness and increased risk of stroke. Although it is too early in the pandemic to know the strength of the association between COVID-19 and stroke, it is an opportune time to review the relationship between acute viral illnesses and stroke. Here, we summarize pathophysiological principles and available literature to guide understanding of how viruses may contribute to ischemic stroke. After a review of inflammatory mechanisms, we summarize relevant pathophysiological principles of vasculopathy, hypercoagulability, and hemodynamic instability. We will end by discussing mechanisms by which several well-known viruses may cause stroke in an effort to inform our understanding of the relationship between COVID-19 and stroke.

Varicella zoster virus anterior uveitis complicated by thalamic stroke

We report a case of varicella zoster virus (VZV)-associated anterior uveitis in a patient with weight loss, arthritis and signs of inflammatory bowel disease. Her clinical course included the development of a thalamic stroke secondary to VZV cerebral vasculopathy. Following antiviral therapy, the patient's neurologic symptoms recovered and her ophthalmic findings improved.

Cerebral vasculitis of medium-sized vessels as a possible mechanism of brain damage in COVID-19 patients

BACKGROUND AND PURPOSE

Cerebral complications related to COVID-19 were recently reported, and the underlying mechanisms of brain damage remain uncertain, probably multifactorial. Among various hypotheses suggested, a possible vasculitis was issued but never confirmed. Herein, we aimed to describe brain MRIs focused on the intracranial vessel wall in a population of COVID-19 patients with neurologic manifestations.

MATERIALS AND METHODS

Between March 1 and May 31, 2020, 69 consecutive COVID-19 patients with neurologic manifestations underwent a brain MRI allowing the study of the intracranial vessel wall at Strasbourg University hospitals and were retrospectively included. During the same period, 25 consecutive patients, without suspicion of SARS-CoV-2 infection, underwent a brain MRI urgently, with the same imaging protocols. A vasculitis seemed likely when imaging demonstrated vessel wall thickening with homogeneous and concentric enhancement.

RESULTS

Among the 69 COVID-19 patients included, 11 (16%) presented arterial vessel wall thickening with homogeneous and concentric enhancement, compatible with cerebral vasculitis. These neuroimaging findings were not found among the 25 patients without SARS-CoV-2 infection, and the difference was statistically significant (p = 0.03). Middle cerebral arteries, basilar artery, and posterior cerebral arteries were the most frequent vessels involved. For nine of them, imaging demonstrated ischemic or hemorrhagic complications.

CONCLUSION

Cerebral vasculitis of medium-sized vessels seems to be one of the mechanisms at the origin of brain damage related to COVID-19.

[Varicella-zoster meningoencephalitis and vasculitis after treatment with amenamevir to herpes zoster in the trigeminal nerve area]

A 78-year-old woman was diagnosed with herpes zoster in the first branch of the trigeminal nerve and was treated with amenamevir. Subsequently, she was hospitalized for postherpetic neuralgia. Fever and unconsciousness were observed, and a diagnosis of varicella-zoster virus meningoencephalitis and vasculitis was made. In addition to the antithrombotic therapy, she was treated with intravenous acyclovir and steroid pulse therapy; however, her unconsciousness persisted. Amenamevir was not transferrable to the spinal fluid and resulted in an incomplete treatment of herpes zoster in the cerebral nerve region, suggesting that this case may be related to the severe course of the disease.

Central nervous system infections produced by varicella zoster virus

PURPOSE OF REVIEW

Varicella zoster virus (VZV) causes varicella, establishes latency, then reactivates to produce herpes zoster. VZV reactivation can also cause central nervous system (CNS) disease with or without rash. Herein, we review these CNS diseases, pathogenesis, diagnosis, and treatment.

RECENT FINDINGS

The most common CNS manifestation of VZV infection is vasculopathy that presents as headache, cognitive decline, and/or focal neurological deficits. VZV vasculopathy has also been associated with cerebral amyloid angiopathy and moyamoya syndrome. Rarely, VZV will produce a meningitis, encephalitis, cerebellitis, and myelopathy. Pathogenic mechanisms include direct VZV infection of affected tissue, persistent inflammation, and/or virus-induced hypercoagulability. Diagnosis is confirmed by the temporal association of rash to disease onset, intrathecal synthesis of anti-VZV antibodies, and/or the presence of VZV DNA in CSF. Most cases respond to intravenous acyclovir with corticosteroids.

SUMMARY

VZV produces a wide spectrum of CNS disorders that may be missed as some cases do not have an associated rash or a CSF pleocytosis. Clinicians must be vigilant in including VZV in their differential diagnosis of CNS infections as VZV is a ubiquitous pathogen; importantly, VZV CNS infections are treatable with intravenous acyclovir therapy and corticosteroids.