International Prevalence and Mechanisms of SARS-CoV-2 in Childhood Arterial Ischemic Stroke During the COVID-19 Pandemic

Steno-occlusive Intracranial Large Vessel Arteriopathies in Childhood: A Pattern Oriented Approach to Neuroimaging Diagnosis

Intracranial steno-occlusive large vessel arteriopathies refer to abnormalities of the arterial wall that typically express luminal stenosis. Notably, some entities that can find themselves within this category may also express luminal dilation, and/or aneurysm formation as an alternative phenotype. Intracranial steno-occlusive large vessel arteriopathies are a leading cause of arterial ischemic stroke (AIS) in children, often progress, and can predispose to recurrent brain infarction. Intracranial arterial dissections account for a subset of cases expressing the focal cerebral arteriopathy (FCA) phenotype because the affected arterial segment, clinical presentation, and AIS patterns are very similar to the inflammatory subtype of FCA.

Trends in the Diagnosis of Pediatric Venous Thromboembolism and Arterial Ischemic Stroke during the COVID-19 Pandemic: An Administrative Database Study

OBJECTIVE

To investigate trends in the diagnosis of venous thromboembolism (VTE) and arterial ischemic stroke (AIS), and examine the use of pharmacological thromboprophylaxis during the COVID-19 pandemic.

STUDY DESIGN

This retrospective cohort study used the Pediatric Health Information Systems database to investigate patients admitted to a participating hospital between January 1, 2018, and December 31, 2021. International Classification of Diseases, 10th edition codes were used to identify VTE, AIS, and COVID-19. Pharmacy billing codes were used to investigate pharmacological thromboprophylaxis use.

RESULTS

1 759 701 unique patients underwent 2 234 135 inpatient admissions. Rate of VTE increased from 84 cases per 10 000 admissions in 2018-2019 to 108 cases per 10 000 admissions in 2020-2021, representing a 28.6% increase (P < .001). In contrast, the rate of AIS remained stable through the study period. When compared with 2018-2019, children diagnosed with VTE during 2020-2021 had longer hospitalizations and were more likely to be admitted to the intensive care unit. When analysis was limited to 2020-2021, a diagnosis code of COVID-19 was associated with a 1.35-fold (95% CI: 1.24-1.45) increase in the odds of VTE diagnosis, but not AIS. Use of pharmacologic thromboprophylaxis increased from 1.5% of hospitalizations in 2018-2019 to 3.0% of hospitalizations in 2020-2021 (P < .001). When evaluating thromboprophylaxis during 2020-2021, a diagnosis code for COVID-19 was associated with an 11-fold (95% CI: 10.86-11.49; P < .001) increase in the utilization of pharmacological thromboprophylaxis.

CONCLUSIONS

This study found an increase in the rate of VTE among hospitalized children during the pandemic. A diagnosis of COVID-19 was associated with a modest increase in odds of VTE diagnosis, which occurred despite increased use of pharmacological thromboprophylaxis.

Rapidly Progressive Contralateral Internal Carotid Artery Stenosis After COVID-19 Infection in a Down Syndrome Patient With Unilateral Moyamoya Arteriopathy

Moyamoya arteriopathy is a condition where chronic, progressive stenosis of large intracranial arteries, primarily of the anterior circulation, results in ischemia and the growth of small, abnormal collateral vessels. There is increasing evidence that infectious pathologies, such as COVID-19, may serve as a sort of trigger, or "second hit," for the development of moyamoya arteriopathy. In this article, we present the case of a 13-year-old female with Down syndrome and unilateral moyamoya arteriopathy who developed contralateral internal carotid artery (ICA) dissection and thrombus in the setting of a positive COVID-19 test and subsequently developed rapidly progressive contralateral ICA and bilateral anterior cerebral artery (ACA) moyamoya-like stenosis. The rapidly progressive contralateral ICA and bilateral ACA moyamoya-like stenosis are likely multifactorial in nature. The contralateral ICA may have had a predisposition for injury and stenosis due to the preexisting moyamoya arteriopathy, making stenosis more likely after COVID-19-induced vascular inflammation and injury as well as after a possible thrombectomy-associated injury. Based on this presentation, patients with moyamoya arteriopathy may be at risk for rapid progression of their moyamoya pathology when exposed to catalysts, including infection, such as COVID-19, and vascular injury, such as thrombectomy-induced injury. In these circumstances, high suspicion and close monitoring are essential for addressing ischemia related to the stenosis before permanent injury.

Association between SARS-CoV-2 Seropositivity and Severity of Out-of-Hospital Acute Ischemic Stroke Following Asymptomatic/Mild COVID-19 in Children

Objective This article investigates the frequency of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) seropositivity and its association with the severity of new-onset acute ischemic stroke (AIS) among previously healthy children with asymptomatic/mild coronavirus disease 2019 (COVID-19).

Methods A case–control study that included children < 18 years with out-of-hospital AIS of undetermined etiology and a control group of healthy children. Exclusion criteria were current respiratory symptoms, previous COVID-19 diagnosis, prior COVID-19 vaccination, active SARS-CoV-2 infection, history of hospital admission in the last 6 months, and having a stroke predisposition. We screened children for SARS-CoV-2 immunoglobulin G antibodies using enzyme-linked immunosorbent assay. The severity of stroke was evaluated using the Pediatric National Institutes of Health Stroke Scale (PedNIHSS).

Results The current study included 25 children (15 males and 10 females; median age 24 months) with out-of-hospital AIS and 25 healthy controls (11 males and 14 females; median age 24 months). SARS-CoV-2 seropositivity was detected in 15 (60%) of AIS children and 11 (44%) among controls (p = 0.258). Compared with seronegative AIS children, those seropositive for SARS-CoV-2 had higher PedNIHSS scores (median 19 vs. 8.5; p = 0.001), pediatric intensive care unit admission (93.3% vs. 40%; p = 0.007), need for mechanical ventilation (53.3% vs. 10%; p = 0.040), and D-dimer levels (median 3.5 vs. 1.75 μg/mL; p < 0.001).

Conclusion SARS-CoV-2 seropositivity may be associated with more severe AIS affecting previously healthy children during the postacute phase of asymptomatic/mildly symptomatic COVID-19.

Thrombotic complications in children with Coronavirus disease 2019 and Multisystem Inflammatory Syndrome of Childhood

Coronavirus disease 2019 (COVID-19) associated coagulopathy is multifactorial and involves inflammation driven hypercoagulability, endothelial dysfunction, platelet activation, and impaired fibrinolysis. Hospitalized adults with COVID-19 are at an increased risk of both venous thromboembolism and ischemic stroke, resulting in adverse outcomes, including increased mortality. Although COVID-19 in children follows a less severe course, both arterial and venous thromboses have been reported in hospitalized children with COVID-19. Additionally, some children develop a postinfectious, hyperinflammatory illness termed multisystem inflammatory syndrome of childhood (MIS-C), which is also associated with hypercoagulability and thrombosis. Several randomized trials have evaluated the safety and efficacy of antithrombotic therapy in adults with COVID-19, although similar pediatric data are lacking. In this narrative review, we discuss the postulated pathophysiology of COVID-19 coagulopathy and summarize principal findings of the recently completed adult trials of antithrombotic therapy. We provide an up-to-date summary of pediatric studies investigating the rate of venous thromboembolism and ischemic stroke in COVID-19 and multisystem inflammatory syndrome of childhood in addition to reviewing the findings of the single, nonrandomized pediatric trial investigating the safety of prophylactic anticoagulation. Lastly, we outline adult and pediatric consensus guidelines on the use of antithrombotic therapy in this cohort. A detailed discussion of the practical implementation and current limitations of published data will hopefully address the knowledge deficits surrounding the use of antithrombotic therapy in children with COVID-19 and generate hypotheses for future research.

The Spectrum of Pediatric Infection-Associated Intracranial Arteriopathies and Acute Ischemic Stroke at 2 Eastern Indian Tertiary Care Centres

INTRODUCTION

Major and minor pediatric infections may cause intracranial arteriopathies, the long-term outcome of which we investigated and identified the factors influencing the progression/resolution of arteriopathies.

METHODS

We collected the clinical and radiological data of children aged 1 month-15 years who had ischemic stroke with definite arteriopathy following a recent febrile infection. Repeated neuroimaging was done over the next year to ascertain recurrent strokes and the progression and resolution of arteriopathies.

RESULTS

The anterior circulation was more frequently affected (83.33%), predominantly involving the middle cerebral artery (41.67%), resolving in 20.84% of cases and progressing in 33.33% of cases. Lesions were commonly unilateral (54.17%) and stenotic (75%), resulting predominantly in cortical infarcts (45.83%), with hemiparesis being the most common neurodeficiency. Apart from tubercular meningitis patients, others had a good functional outcome.

CONCLUSION

Lower age, minor infections, and unilateral arteriopathies had a significantly higher chance of resolution. Postviral arteriopathies had a significantly lower chance of progression compared with those following bacterial infections. Progressive and bilateral arteriopathies were significantly associated with worse outcomes and recurrent strokes.

Pediatric Ischemic Stroke

OBJECTIVE

Pediatric cerebrovascular disease is one of the leading causes of death and disability in children. Survivors of childhood stroke and their families are often left to cope with long-lasting sequelae, such as barriers to school reentry and long-term challenges in attaining independence as adults. Because childhood stroke is rare and providers may not be familiar with the disorder, this article reviews the risk factors, acute management, and sequelae of ischemic stroke in children.

LATEST DEVELOPMENTS

High-quality evidence has resulted in an organized approach to emergent treatment of ischemic stroke in adults, but most front-line providers are less prepared for emergent stroke management in children. The level of evidence for reperfusion therapies in children remains low but is growing. Thrombolysis and thrombectomy are sometimes considered for hyperacute treatment of stroke in children. Readiness for pediatric stroke at regional centers should include an organized approach to pediatric stroke triage and management based on extrapolation from adult stroke trials, expert consensus, and emerging pediatric studies.

ESSENTIAL POINTS

This review provides up-to-date information about ischemic stroke risk factors and management in children. Preparation for rapid stroke diagnosis and management in children may improve outcomes.

Advances in the Diagnosis and Treatment of Pediatric Arterial Ischemic Stroke

Though rare, stroke in infants and children is an important cause of mortality and chronic morbidity in the pediatric population. Neuroimaging advances and implementation of pediatric stroke care protocols have led to the ability to rapidly diagnose stroke and in many cases determine the stroke etiology. Though data on efficacy of hyperacute therapies, such as intravenous thrombolysis and mechanical thrombectomy, in pediatric stroke are limited, feasibility and safety data are mounting and support careful consideration of these treatments for childhood stroke. Recent therapeutic advances allow for targeted stroke prevention efforts in high-risk conditions, such as moyamoya, sickle cell disease, cardiac disease, and genetic disorders. Despite these exciting advances, important knowledge gaps persist, including optimal dosing and type of thrombolytic agents, inclusion criteria for mechanical thrombectomy, the role of immunomodulatory therapies for focal cerebral arteriopathy, optimal long-term antithrombotic strategies, the role of patent foramen ovale closure in pediatric stroke, and optimal rehabilitation strategies after stroke of the developing brain.

Thrombotic Events in MIS-C Patients: A Single Case Report and Literature Review

Multisystem Inflammatory Syndrome in Children (MIS-C) is a systemic hyperinflammatory disorder that is associated with a hypercoagulable state and a higher risk of thrombotic events (TEs). We report the case of a 9-year-old MIS-C patient with a severe course who developed a massive pulmonary embolism that was successfully treated with heparin. A literature review of previous TEs in MIS-C patients was conducted (60 MIS-C cases from 37 studies). At least one risk factor for thrombosis was observed in 91.7% of patients. The most frequently observed risk factors were pediatric intensive care unit hospitalization (61.7%), central venous catheter (36.7%), age >12 years (36.7%), left ventricular ejection fraction <35% (28.3%), D-dimer >5 times the upper limit of normal values (71.9%), mechanical ventilation (23.3%), obesity (23.3%), and extracorporeal membrane oxygenation (15%). TEs may concurrently affect multiple vessels, including both arterial and venous. Arterial thrombosis was more frequent, mainly affecting the cerebral and pulmonary vascular systems. Despite antithrombotic prophylaxis, 40% of MIS-C patients developed TEs. Over one-third of patients presented persistent focal neurological signs, and ten patients died, half of whom died because of TEs. TEs are severe and life-threatening complications of MIS-C. In case with thrombosis risk factors, appropriate thromboprophylaxis should be promptly administered. Despite proper prophylactic therapy, TEs may occur, leading in some cases to permanent disability or death.

Neurological consequences of SARS-CoV-2 infections in the pediatric population

COVID-19 in the pediatric population is mostly asymptomatic. However, 1 out of 5 children presents non-specific neurologic symptoms such as headache, weakness, or myalgia. Furthermore, rarer forms of neurological diseases are increasingly being described in association to a SARS-CoV-2 infection. Encephalitis, stroke, cranial nerves impairment, Guillain-Barré syndrome or acute transverse myelitis have been reported and account for around 1% of pediatric COVID-19 cases. Some of these pathologies may occur during or after the SARS-CoV-2 infection. The pathophysiological mechanisms range from direct invasion of the central nervous system (CNS) by SARS-CoV-2 itself to postinfectious immune-mediated CNS inflammation. In most cases, patients presenting neurological pathologies related to SARS-CoV-2 infection are at greater risk of life-threatening complications and should be closely monitored. Further studies are needed to acknowledge the potential long-term neurodevelopmental consequences of the infection.

Diagnosis of Pediatric Stroke in Resource Limited Settings

Global awareness of stroke as a significant cause of neurologic sequelae and death in children has increased over the years as more data in this field becomes available. However, most published literature on pediatric stroke have limited geographic representation. Data on childhood stroke from developing countries remains limited. Thus, this paper reviewed geographic/ethnic differences in pediatric stroke risk factors highlighting those reported in low- and middle-income countries, and proposes a childhood arterial ischemic stroke diagnostic algorithm for resource limited settings. Stroke risk factors include cardiac disorders, infectious diseases, cerebral arteriopathies, hematologic disorders, inflammatory diseases, thrombophilia and genetic conditions. Infection of the central nervous system particularly tuberculous meningitis, is a leading cause of pediatric arterial ischemic stroke in developing countries. Stroke should be considered in children with acute focal neurologic deficit especially in the presence of aforementioned risk factors. Cranial magnetic resonance imaging with angiography is the neuroimaging modality of choice but if unavailable, cranial computed tomography with angiography may be performed as an alternative. If both are not available, transcranial doppler together with neurologic exam may be used to screen children for arterial ischemic stroke. Etiological diagnosis follows with the aid of appropriate laboratory tests that are available in each level of care. International collaborative research on stroke risk factors that are prevalent in low and middle income countries will provide information for drafting of stroke care guidelines that are universal yet inclusive taking into consideration regional differences in available resources with the goal of reducing global stroke burden.

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.

SARS-CoV-2 Infection and Increased Risk for Pediatric Stroke

BACKGROUND

There is an increased risk of stroke in adults with severe acute respiratory syndrome coronavirus 2 (coronavirus disease 2019 [COVID-19]) infection, but whether there is a similar association with stroke in children is unclear. Our objective was to determine whether there is a correlation between COVID-19 infection, multisystem inflammatory syndrome in children (MIS-C), and pediatric ischemic stroke.

METHODS

This was a retrospective, population-based cohort analysis between March 1, 2020, and June 30, 2021, conducted at a children's hospital. Pediatric patients with a diagnosis of ischemic stroke were identified using ICD-10 diagnoses of ischemic stroke, cerebrovascular accident, or cerebral infarction.

RESULTS

We identified 16 patients, seven male and nine female, with ischemic stroke. Ages were 8 months to 17 years (median 11.5 years). More Asian (6%) and black (13%) patients had strokes compared with population prevalence (2% each, respectively). No patients had active COVID-19 infection. COVID-19 antibodies were identified in five of 11 patients tested (45%), of whom three were diagnosed with MIS-C. 82% of the strokes occurred between February and May 2021. The peak incidence was in February 2021, which was two months after peak incidence of pediatric cases of COVID-19 and one month after the peak of MIS-C cases.

CONCLUSIONS

Our study suggests that prior COVID-19 infection, but not acute infection, is correlated with a risk for stroke in the pediatric population. The risk for stroke appears to be distinct from the risk for MIS-C.

Hemostatic and Thrombotic Considerations in the Diagnosis and Management of Childhood Arterial Ischemic Stroke: A Narrative Review

Although rare in children, arterial ischemic stroke (AIS) is associated with increased mortality and neurological morbidity. The incidence of AIS after the neonatal period is approximately 1-2/100,000/year, with an estimated mortality of 3-7%. A significant proportion of children surviving AIS experience life-long neurological deficits including hemiparesis, epilepsy, and cognitive delays. The low incidence of childhood AIS coupled with atypical clinical-presentation and lack of awareness contribute to delay in diagnosis and consequently, the early initiation of treatment. While randomized-clinical trials have demonstrated the efficacy and safety of reperfusion therapies including thrombolysis and endovascular thrombectomy in appropriately-selected adult patients, similar data for children are unavailable. Consequently, clinical decisions surrounding reperfusion therapy in childhood AIS are either extrapolated from adult data or based on local experience. The etiology of childhood AIS is multifactorial, often occurring in the setting of both acquired and congenital risk-factors including thrombophilia. While multiple studies have investigated the association of thrombophilia with incident childhood AIS, its impact on stroke recurrence and therefore duration and intensity of antithrombotic therapy is less clear. Despite these limitations, a significant progress has been made over the last decade in the management of childhood AIS. This progress can be attributed to international consortiums, and in selected cohorts to federally-funded clinical trials. In this narrative review, the authors have systematically appraised the literature and summarize the hemostatic and thrombotic considerations in the diagnosis and management of childhood AIS focusing on the evidence supporting reperfusion therapies, relevance of thrombophilia testing, and duration and drug choices for secondary-prophylaxis.

Thromboembolic complications in children with COVID-19 and MIS-C: A narrative review

COVID-19 and multisystem inflammatory syndrome in children (MIS-C) have been associated with a higher incidence of hypercoagulability and thromboembolic events (TEs), even in children, leading to relevant morbidity, and mortality. However, our understanding of such complications in childhood is limited. To better understand the incidence, clinical manifestations, risk factors, and management of COVID-19 and MIS-C-related TEs in children, a review of the current literature and a brief update on pathophysiology are given. Sixty-two studies, describing 138 patients with TEs associated with COVID-19 or MIS-C, were included. The overall number of TEs was 157, as 16 patients developed multiple TEs: venous TEs represented the majority (54%), followed by arterial thrombosis (38%, mainly represented by arterial ischemic stroke-AIS), and intracardiac thrombosis (ICT) (8%). Within the venous TEs group, pulmonary embolism (PE) was the most frequent, followed by deep venous thrombosis, central venous sinus thrombosis, and splanchnic venous thrombosis. Notably, 10 patients had multiple types of venous TEs, and four had both venous and arterial thrombosis including a newborn. Most of them (79 cases,57%) had at least one predisposing condition, being obesity the most frequent (21%), especially in patients with PE, followed by malignancy (9%). In 35% of cases, no data about the outcome were available About one-third of cases recovered, 12% improved at discharge or follow-up, and 6% had persistent neurological sequelae. The mortality rate was 12%, with death due to comorbidities in most cases. Most fatalities occurred in patients with arterial thrombosis. Pediatricians should be aware of this life-threatening possibility facing children with SARS-CoV-2 infection or its multisystemic inflammatory complication, who abruptly develop neurological or respiratory impairment. A prompt intensive care is essential to avoid severe sequelae or even exitus.