Transient cerebral arteriopathy in infancy associated with enteroviral infection

Evidence of varicella zoster virus (VZV) reactivation in children with arterial ischemic stroke: Results of the VIPS II Study

Background

Varicella zoster virus (VZV) has been associated with focal cerebral arteriopathy (FCA) and arterial ischemic stroke (AIS) in childhood. The Vascular effects of Infection in Pediatric Stroke (VIPS) II study aimed to examine this relationship in the modern era when most children in North America and Australia receive VZV vaccination with live, attenuated virus.

Methods

This 22-center prospective cohort study enrolled 205 children (28 days-18 years) with AIS (2017-2022), collected baseline [hyperacute (≤72 hours; n=194) and acute (4-6 days; n=181)] and convalescent (1-6 weeks; n=74) serum samples. Sites enrolled 95 stroke-free controls with single serum samples. A virology research laboratory measured VZV IgM and IgG titers by an in-house enzyme-linked immunosorbent assay (ELISA). Baseline IgG seropositivity indicated prior exposure (vaccination/infection) and elevated IgM titers indicated recent reactivation.

Results

Median (IQR) age was 11.6 (5.5-15.6) years for cases and 11.8 (6.8-15.3) years for controls. Baseline serologies indicated prior VZV exposure in 198 cases (97%) and all controls. Parents of cases reported VZV vaccination in 160 (78%) and remote chicken pox in three (1.4%). Twenty cases (9.8%) and three controls (3.1%) had serologic evidence of recent VZV reactivation (p=0.06); all had remote VZV exposure (vaccination in 19 cases and all controls) and all were asymptomatic. Recent VZV reactivation was seen in similar proportions in arteriopathic, cardioembolic, and idiopathic stroke. Of 32 cases of FCA, 4 (12.5%) had recent VZV reactivation, versus no cases of arterial dissection (n=10) or moyamoya (n=16).

Conclusions

Serologic evidence of recent VZV reactivation (≈1-6 weeks prior to stroke) was present in one in 10 cases of childhood AIS, including those without arteriopathy. Clinically silent VZV reactivation may be a childhood stroke trigger despite widespread vaccination. These cases could represent waning immunity with reactivation of either vaccine virus or wild-type virus after an unrecognized secondary VZV infection.

Transient posterior cerebral arteriopathy: An unusual case enterovirus-related

Transient Cerebral Arteriopathy (TCA) is one of the main causes of childhood stroke. Here we present an unusual case of Arterial Ischemic Stroke (AIS) caused by a TCA of posterior flow and originally located in the right thalamus. The detection of enterovirus in the cerebrospinal fluid allowed us to suppose a probable post infectious etiology. The course of symptoms was self-limited and the child had a complete clinical recovery after five days. A new ischemic lesion on the antero-inferior paravermian region of the left cerebellum was revealed by a following brain Magnetic Resonance Imaging (MRI) three months later and these findings were reported by further brain MRI control performed after 15 months. Comparing follow up Magnetic Resonance Angiography (MRA) with previous High Resolution Vessel Wall Magnetic Resonance Imaging (HRMI), we found a vessel narrowing at the level of the Posterior Inferior Cerebellar Artery that might explain the arteriopathy process. In conclusion, clinical and radiological course allow us to speculate that this multifocal cerebral arteriopathy might be a transient lesion due to enterovirus infection. To our knowledge, there are only three articles describing TCA enterovirus-related, and brain MRA was performed in only one case; in addition, no one with the involvement of the posterior circulation.

Pediatric Stroke Imaging

BACKGROUND

Pediatric stroke is a distinct clinical entity as compared with that in adults due to its unique and diverse set of etiologies. Furthermore, the role and application of diagnostic imaging has specific constraints and considerations. The intention of this article is to review these concepts in a thorough manner to offer a pediatric stroke imaging framework that providers can employ when taking care of these patients.

METHODS

A comprehensive primary and secondary literature review was performed with specific attention to the common causes of pediatric stroke, appropriate use of neuroimaging, specific imaging findings, and developing techniques which may improve our ability to accurately diagnose these patients.

RESULTS

Findings from this literature review were synthesized and summarized in order to thoroughly review the aforementioned concepts and outline the current consensus-based approach to diagnostic imaging in pediatric stroke. Furthermore, imaging findings drawn from patients seen in our institution are demonstrated to familiarize readers with pediatric stroke neuroimaging.

CONCLUSIONS

The challenges posed by pediatric stroke can be mitigated, in part, by the thoughtful application of diagnostic imaging, with the ultimate hope of improving outcomes for these vulnerable patients.

Cerebral vasculitis and intracranial multiple aneurysms in a child with Lyme neuroborreliosis

Introduction. Lyme borreliosis is a multisystem tick-borne disease caused by Borrelia burgdorferi. Neurological manifestations are reported in up to 15 % of adult patients with Lyme disease, while the frequency among children is higher. The most common manifestations are painful radiculopathy, facial nerve paresis and lymphocytic meningitis. Epileptic seizures and cerebral vasculitis with stroke or aneurysms are very rare complications.

Case presentation. We describe a paediatric patient with sensorineural auditory dysfunction, headache, fatigue and epileptic seizures as sequelae of meningoencephalitis/Lyme neuroborreliosis (LNB) caused by B. burgdorferi. Brain magnetic resonance imaging revealed widespread enhancement of the leptomeninges, cranial nerves and artery walls compatible with vasculitis and disturbances in cerebrospinal fluid (CSF) circulation. The patient was treated with ceftriaxone for 2 weeks. Two years later, the patient had an ischemic stroke. Brain magnetic resonance angiography revealed multiple aneurysms, which were not present previously. The largest aneurysm was operated rapidly. The patient was treated with another course of intravenous ceftriaxone for 4 weeks and pulse therapy with corticosteroids. He recovered well.

Neuroinflammation in Ischemic Pediatric Stroke

Over the last decades, the importance of inflammatory processes in pediatric stroke have become increasingly evident. Ischemia launches a cascade of events: activation and inhibition of inflammation by a large network of cytokines, adhesion and small molecules, protease, and chemokines. There are major differences in the neonatal brain compared to adult brain, but developmental trajectories of the process during childhood are not yet well known. In neonatal stroke ischemia is the leading pathophysiology, but infectious and inflammatory processes have a significant input into the course and degree of tissue damage. In childhood, beside inflammation lanced by ischemia itself, the event of ischemia might be provoked by an underlying inflammatory pathophysiology: transient focal arteriopathy, dissection, sickle cell anemia, Moyamoya and more generalized in meningitides, generalized vasculitis or genetic arteriopathies (as in ADA2). Focal inflammatory reactions tend to be located in the distal part of the carotid artery or the proximal medial arteries, but generalized processes rather tend to affect the small arteries.

Immunotherapy for arterial ischaemic stroke in childhood: a systematic review

BACKGROUND

There is little evidence about either prevention or treatment of childhood arterial ischaemic stroke (AIS). However, drugs that regulate the immune and inflammatory response could theoretically prevent occurrence or recurrence of AIS. Additionally, as an acute treatment, they may limit the neurological damage caused by AIS. Here, we systematically review the evidence on the use of immunotherapy in childhood AIS.

DESIGN

A systematic review of publications in databases Embase and Medline from inception. All types of evidence were included from trials, cohorts, case-control and cross-sectional studies and case reports.

RESULTS

34 reports were included: 32 observational studies and 2 trials. Immunotherapy was used in two key patient groups: arteriopathy and acute infection. The majority were cases of varicella and primary angiitis of the central nervous system. All three cohorts and 80% of the case studies were treated with steroids. Recurrence rates were low. Analytical studies weakly associated steroids with lower odds of new stroke and neurological deficits, and better cognitive outcomes in the context of Moyamoya disease and tuberculosis.

CONCLUSIONS

Immunotherapies are used in children with AIS, mainly as steroids for children with arteriopathy. However, there is currently little robust evidence to either encourage or discourage this practice. There is weak evidence consistent with the hypothesis that in certain children at risk, steroids may both reduce the risk of occurrent/recurrent stroke and enhance neurological outcomes. As the potential benefit is still uncertain, this indicates that a trial of steroids in childhood AIS may be justified.

Inflammatory markers in pediatric stroke: An attempt to better understanding the pathophysiology

BACKGROUND

The mechanisms of childhood and perinatal arterial ischemic stroke (AIS) are poorly understood. Multiple risk factors include cerebral arteriopathy, congenital cardiac disease, infection, sickle cell disease, and maternal-fetal conditions in neonates. For infections and parainfectious conditions being the most important a possible inflammatory pathophysiology has long been suspected. This pilot study aims to detect, whether there are any abnormalities of inflammatory markers associated with childhood and neonatal stroke.

METHODS

The concentration of 23 different metalloproteinases (MMPs), tissue inhibitors of MMPs (TIMPs), endothelial factors, vascular cell adhesion proteins, and cytokines in plasma were measured in 12 children with AIS, 7 healthy age matched controls and 6 full term neonates with perinatal AIS.

RESULTS

At the time of the acute event children with AIS had significantly elevated levels of MMP-9, TIMP4, IL-6, IL-8 and CRP compared to controls (p < 0.05). Except for lower IL-6 and CRP levels the pattern of children with a history of varizella-zoster virus (VZV) and other viral infections did not differ to the non-infectious group. Median levels of MMP-1, MMP-2, TIMP-1, TIMP-2, sE-selectin, sICAM-1, sVCAM-1, IL-8, IL-10, TNF-alpha, VEGF, Fetuin A were found to be higher in the neonatal group when compared with older children.

CONCLUSION

This pilot study supports the assumption of an inflammatory process and up-regulation of metalloproteinases and their inhibitors, and altered pattern of circulating pro-inflammatory cytokines, CRP and vWF levels in pediatric and neonatal AIS. It highlights the feasibility but also difficulties for similar larger future studies that should aim to clarify childhood stroke etiopathogenesis and consecutive further therapeutic options.

Childhood infections and trauma as risk factors for stroke

Stroke is as common as brain tumor in children. The etiology of childhood arterial ischemic stroke (AIS) appears to be multifactorial, resulting from the interaction between genetic predisposition and environmental triggers. The risk factors for AIS in children are markedly different from the atherosclerotic risk factors in adults. Trauma and infections have been identified as associations in previous studies and are exposures of particular interest because of their increased prevalence in the children. The aim of this review article is to provide an overview of the research studies that have addressed the role of infections and trauma in pediatric AIS.

Mechanisms of pediatric cerebral arteriopathy: an inflammatory debate

Arteriopathy is the leading cause of childhood arterial ischemic stroke, but its mechanisms are poorly understood. This review explores the possible role of inflammatory mechanisms and evidence for inflammatory pathophysiology in specific pediatric cerebral arteriopathies. Pathologically proven small-vessel central nervous system vasculitis provides a definitive inflammatory model where available treatments are likely improving outcomes. In contrast, a common large-vessel arteriopathy presents many features suggestive of inflammation, but definitive proof remains elusive. Recent advances and future research directions, including biomarker, neuroimaging, and pathologic approaches and how they might address these important clinical questions, are discussed.

The course of unilateral intracranial arteriopathy in young adults with arterial ischemic stroke

BACKGROUND AND PURPOSE

Unilateral intracranial focal nonprogressive arteriopathy is often found in children with arterial ischemic stroke. We aimed to investigate the course of unilateral intracranial arteriopathy in young adults.

METHODS

We searched the Utrecht Stroke Database for patients between 16 and 50 years of age diagnosed with anterior circulation arterial ischemic stroke and a nonatherosclerotic, unilateral intracranial large-artery arteriopathy between 1991 and 2005. We assessed clinical features, potential causes, risk factors, extent of infarction and arteriopathy at presentation, long-term angiographic course, and clinical outcome.

RESULTS

Of 356 patients with anterior circulation arterial ischemic stroke, 17 (5%) had a documented unilateral intracranial arteriopathy, of whom 14 could be included for follow-up investigations (median age, 34 years; range, 27-49 years). Median duration of follow-up was 8.8 years (range, 1.7-12.8 years). In 11 patients, onset of symptoms was not abrupt. The arteriopathy normalized completely in 5 and improved in 3 patients; in none of the patients did the arteriopathy worsen. Two of 14 patients had recurrent symptoms. Ten patients (71%) had a good outcome (modified Rankin Scale score≤2).

CONCLUSIONS

In young adults, arterial ischemic stroke is rarely caused by a unilateral intracranial arteriopathy. Similar to children, onset of symptoms in young adults is often not abrupt and the arteriopathy may improve over time. Late recurrences were rare. Possibly, a monophasic inflammatory process, as has been suggested for childhood intracranial focal nonprogressive arteriopathies, also occurs in young adults.

The vascular effects of infection in Pediatric Stroke (VIPS) Study

Understanding the vascular injury pathway is crucial to developing rational strategies for secondary stroke prevention in children. The multicenter Vascular Effects of Infection in Pediatric Stroke (VIPS) cohort study will test the hypotheses that (1) infection can lead to childhood arterial ischemic stroke by causing vascular injury and (2) resultant arteriopathy and inflammatory markers predict recurrent stroke. The authors are prospectively enrolling 480 children (aged 1 month through 18 years) with arterial ischemic stroke and collecting extensive infectious histories, blood and serum samples (and cerebrospinal fluid, when clinically obtained), and standardized brain and cerebrovascular imaging studies. Laboratory assays include serologies (acute and convalescent) and molecular assays for herpesviruses and levels of inflammatory markers. Participants are followed prospectively for recurrent ischemic events (minimum of 1 year). The analyses will measure association between markers of infection and cerebral arteriopathy and will assess whether cerebral arteriopathy and inflammatory markers predict recurrent stroke.

Ischemic stroke associated with adenoviral infection in a 4-year-old boy

We present a case of childhood arterial ischemic stroke associated with proven adenoviral upper respiratory tract infection in a previously healthy 4-year-old boy. Adenoviral meningitis and encephalitis have been reported repeatedly, thus confirming the neuroinvasive capability of these viruses. However, an association between adenoviral infection and arterial ischemic stroke has not been described thus far. HIV and varicella zoster virus are the only microorganisms that have been consistently associated with arterial ischemic stroke in the absence of acute central nervous system infection. In HIV-infected individuals ischemic stroke can be caused by vasculitis and hypercoagulability. Granulomatous arteritis of the vessel wall causes post-varicella cerebral infarction and ischemic stroke after herpes zoster ophthalmicus. We suggest that in our patient a post-varicella cerebral infarction-like mechanism of adenoviral spread to the affected artery wall occurred through the ophthalmic branch of the trigeminal nerve. Adenoviruses are neuroinvasive and inflamed conjunctiva might have permitted introduction of the virus into ophthalmic nerve tissue. In consequence, the stenotic lesion of the artery might have been induced by the presence of adenovirus and the subsequent inflammatory reaction. We recommend a prompt quest for adenoviral infection in all previously healthy children with fever and clinical presentation compatible with ischemic stroke, because timely diagnosis and treatment could improve the outcome and hasten neurological recovery.

Predictors of cerebral arteriopathy in children with arterial ischemic stroke: results of the International Pediatric Stroke Study

BACKGROUND

Cerebral arteriopathies, including an idiopathic focal cerebral arteriopathy of childhood (FCA), are common in children with arterial ischemic stroke and strongly predictive of recurrence. To better understand these lesions, we measured predictors of arteriopathy within a large international series of children with arterial ischemic stroke.

METHODS AND RESULTS

Between January 2003 and July 2007, 30 centers within the International Pediatric Stroke Study enrolled 667 children (age, 29 days to 19 years) with arterial ischemic stroke and abstracted clinical and radiographic data. Cerebral arteriopathy and its subtypes were defined using published definitions; FCA was defined as cerebral arterial stenosis not attributed to specific diagnoses such as moyamoya, arterial dissection, vasculitis, or postvaricella angiopathy. We used multivariate logistic regression techniques to determine predictors of arteriopathy and FCA among those subjects who received vascular imaging. Of 667 subjects, 525 had known vascular imaging results, and 53% of those (n=277) had an arteriopathy. The most common arteriopathies were FCA (n=69, 25%), moyamoya (n=61, 22%), and arterial dissection (n=56, 20%). Predictors of arteriopathy include early school age (5 to 9 years), recent upper respiratory infections, and sickle cell disease, whereas prior cardiac disease and sepsis reduced the risk of arteriopathy. The only predictor of FCA was recent upper respiratory infection.

CONCLUSIONS

Arteriopathy is prevalent among children with arterial ischemic stroke, particularly those presenting in early school age, and those with a history of sickle cell disease. Recent upper respiratory infection predicted cerebral arteriopathy and FCA in particular, suggesting a possible role for infection in the pathogenesis of these lesions.

The course and outcome of unilateral intracranial arteriopathy in 79 children with ischaemic stroke

Arteriopathies are the commonest cause of arterial ischaemic stroke (AIS) in children. Repeated vascular imaging in children with AIS demonstrated the existence of a ‘transient cerebral arteriopathy’ (TCA), characterized by lenticulostriate infarction due to non-progressive unilateral arterial disease affecting the supraclinoid internal carotid artery and its proximal branches. To further characterize the course of childhood arteriopathies, and to differentiate TCA from progressive arterial disease, we studied the long-term evolution of unilateral anterior circulation arteriopathy, and explored predictors of stroke outcome and recurrence. From three consecutive cohorts in London, Paris and Utrecht, we reviewed radiological studies and clinical charts of 79 previously healthy children with anterior circulation AIS and unilateral intracranial arteriopathy of the internal carotid bifurcation, who underwent repeated vascular imaging. The long-term evolution of arteriopathy was classified as progressive or TCA. Clinical and imaging characteristics were compared between both groups. Logistic regression modelling was used to determine possible predictors of the course of arteriopathy, functional outcome and recurrence. After a median follow-up of 1.4 years, 5 of 79 children (6%) had progressive arteriopathy, with increasing unilateral disease or bilateral involvement. In the others (94%), the course of arteriopathy was classified as TCA. In 23% of TCA patients, follow-up vascular imaging showed complete normalization, the remaining 77% had residual arterial abnormalities, with improvement in 45% and stabilization in 32%. Stroke was preceded by chickenpox in 44% of TCA patients, and in none of the patients with progressive arteriopathies. Most infarcts were localized in the basal ganglia. In 14 (19%) of TCA patients, transient worsening of the arterial lesion was demonstrated before the arteriopathy stabilized or improved. Thirteen TCA patients (18%) had a recurrent stroke or TIA. Thirty TCA patients (41%) had a good neurological outcome, compared with none of the five patients with progressive arteriopathy. Arterial occlusion, moyamoya vessels and ACA involvement were more frequent in progressive arteriopathies. Cortical infarct localization was significantly associated with poor neurological outcome (OR 6.14, 95% CI 1.29–29.22, P = 0.02), while there was a trend for occlusive arterial disease to predict poor outcome (OR 3.00, 95% CI 0.98–9.23, P = 0.06). Progressive arteriopathy was associated with recurrence (OR 18.77, 95%CI 1.94–181.97, P = 0.01). The majority of childhood unilateral intracranial anterior circulation arteriopathies (94%) have a course that is consistent with TCA, in which transient worsening is common. Although the arterial inflammation probably causing TCA is ‘transient’, most children are left with permanent arterial abnormalities and residual neurological deficits.

Cerebrospinal fluid analysis in the diagnosis and treatment of arterial ischemic stroke

With the advent of magnetic resonance imaging as a rapid and accurate way to diagnose arterial ischemic stroke, cerebrospinal fluid assessment is rarely performed, unless infectious or inflammatory processes are obvious. Recent advances in the understanding of the pathophysiology of childhood stroke have implicated a growing list of discrete or occult infectious and inflammatory conditions which may involve intracranial arteries and neighboring structures. Cerebrospinal-fluid assessment may allow the detection of markers identifying processes (including infectious, inflammatory, metabolic, and traumatic) potentially involved in cerebral vasculopathy and stroke. The analysis of cerebrospinal fluid in arterial ischemic strokes, including apparently idiopathic strokes, may yield essential information on pathophysiology, allowing for optimal therapeutic decisions and prognostic considerations.

Stroke in Childhood

BACKGROUND

Childhood stroke is increasingly recognized as an important cause of morbidity and mortality. Risk factors for stroke in childhood are different than those traditionally seen in adults.

REVIEW SUMMARY

This review summarizes, in brief, the epidemiology, risk factors, evaluation, treatment, outcome, and recurrence risk of children with arterial ischemic stroke (AIS). Areas of controversy and those that require further study are highlighted. Tables summarizing important points of the history, physical examination, and diagnostic evaluation of AIS are provided.

CONCLUSIONS

Children with stroke should be carefully evaluated for risk factors and possible etiology of stroke. At the present time, treatment is based upon extrapolation from the adult literature and expert opinion, as no evidence-based guidelines exist, except in sickle cell anemia. International, multicenter trials are beginning and should provide some answers over the next few years.

Toward the definition of cerebral arteriopathies of childhood

PURPOSE OF REVIEW

To facilitate and standardize the diagnosis of cerebrovascular conditions in childhood, particularly in the field of arterial ischemic diseases.

RECENT FINDINGS

Progress in diagnostic techniques in the past decade have led to newly established etiologies for childhood stroke, most of which represent some form of vascular pathology. These advances must be integrated into a modern nomenclature system with revised definitions of stroke and arterial wall diseases-arteriopathies-in childhood.

SUMMARY

This nomenclature system is intended to facilitate and enhance clinical research in childhood stroke, particularly multicenter collaborative studies.