Prothrombotic abnormalities in childhood ischaemic stroke

Internal Carotid Artery Dissection With Thrombosis in a Child With Prothrombin Gene Mutation

Prothrombin gene mutation (prothrombin thrombophilia) is an inherited disorder that increases the risk of venous thrombosis. However, limited data exist on the risk of arterial stroke in an at-risk population. Several meta-analyses report slightly increased risk in specific populations. We report a 10-year-old Hispanic girl who presented to the emergency department with a seizure. This seizure occurred five days after she tripped and fell without any initial associated symptoms. She had left-sided hemiparesis on physical examination after the seizure. Imaging revealed internal carotid artery (ICA) dissection with thrombus, right caudate nucleus and putamen infarcts, and ischemic penumbra. She subsequently had an endovascular thrombectomy of the right ICA with reperfusion. Genetic testing showed a prothrombin gene mutation (G20210A). Prothrombin gene mutation was the most likely explanation for her stroke in the absence of a significant risk factor for arterial thrombosis or an underlying hypercoagulable disorder. Further investigations are required to determine the risks and evaluate the correlation between prothrombin gene mutation and ischemic stroke in children.

Pediatric vs. adult stroke: comparative study in a tertiary referral hospital, Cairo, Egypt

Background

Even though stroke is rare in children, it is associated with serious or life-threatening consequences. Despite its rarity, the occurrence of stroke in children has age-related differences in risk factors, etiopathogenesis, and clinical presentations. Unlike adults, who have arteriosclerosis as the major cause of stroke, risk factors for pediatric strokes are multiple, including cardiac disorders, infection, prothrombotic disorders, moyamoya disease, moyamoya syndrome, and others. The goal of the current study was to compare the characteristics, clinical features, etiology, subtypes, and workup of pediatric and adult strokes.

Methods

This was a hospital-based observational study conducted on 222 participants. All patients underwent a full clinical and neurological examination, full laboratory study, cardiac evaluation, and neuroimaging; CT scan, MRI, MRA, MRV, carotid duplex, and transcranial Doppler (TCD). Ischemic stroke (IS) etiology was classified according to the Trial of Org 10172 in Acute Stroke Treatment (TOAST) criteria, the "proposed classification for subtypes of arterial ischemic stroke in children," and the Oxfordshire Community Stroke Project (OCSP). Stroke severity was determined by the National Institutes of Health Stroke Scale (NIHSS) and PedNIHSS on admission.

Results

The proportion of pediatric ischemic strokes in the current study was 63.4 percent, while hemorrhagic strokes were 36.5%. The majority of the adult patients had ischemic strokes (84.1%), while hemorrhagic strokes were noted in 15.8% of the patients. According to the original TOAST classification, in the current study, the etiology of pediatric IS was other determined causes in 63.6%, undetermined etiology in 27.2%, and cardioembolic in 9.0%. For the adult group, the major stroke subtypes were large artery disease, small vessel disease, cardioembolic, other determined causes, and undetermined etiology at 49.6%, 28.6%, 6.9%, 0.6%, and 12.5%, respectively.

Conclusions

There is a greater etiological role for non-atherosclerotic arteriopathies, coagulopathies, and hematological disorders in pediatric stroke, while adults have more atherothrombotic causes. The co-existence of multiple risk factors in pediatric ischemic stroke is noticed. Thrombophilia evaluation is helpful in every case of childhood stroke. Children who have had a stroke should undergo vascular imaging as soon as possible. Imaging modalities include TCD and Doppler ultrasound, CT, MRI, MRA, and MRV, and cerebral angiography.

Arteriell ischämischer Schlaganfall im Kindes- und Jugendalter

Der arteriell ischämische Schlaganfall im Kindes- und Jugendalter gehört zu den zeitkritischsten pädiatrischen Notfällen, wird aber häufig erst mit prognostisch relevanter Zeitverzögerung diagnostiziert. Gründe sind geringe „Awareness“, die zuweilen unspezifische klinische Präsentation mit einer Breite an kritischen Differenzialdiagnosen und in der Fläche noch wenig verzahnte Akutversorgungsstrukturen. Die beim Erwachsenen etablierten Revaskularisationsstrategien zeigen auch beim Kind mögliche, z. T. spektakuläre Erfolge. Diese sind daher nach Möglichkeit auch betroffenen Kindern zur Verfügung zu stellen, auch wenn hier derzeit keine annähernd vergleichbare Evidenz vorliegt. Postakut ist die ätiologische Aufarbeitung aufgrund zu bedenkender Risikofaktoren komplex, muss aber das individuelle Risikoprofil mit Sekundärprophylaxe, Rezidivrisiko und Outcome präzise identifizieren. Die Langzeitbetreuung im multiprofessionellen, interdisziplinären Team muss die bio-psycho-sozialen Aspekte des Kindes in seiner jeweiligen Entwicklungsphase berücksichtigen.

Notfall-Neuropädiatrie – Der arteriell ischämische Schlaganfall als einer der zeitkritischsten Notfälle bei Kindern und Jugendlichen

Der arteriell ischämische Schlaganfall im Kindes- und Jugendalter gehört zu den zeitkritischsten Notfällen in der Pädiatrie. Dennoch wird er häufig mit einer oft prognostisch relevanten Zeitverzögerung diagnostiziert. Gründe dafür liegen neben der geringen Awareness auch in der zuweilen unspezifischen klinischen Präsentation mit einer herausfordernden Breite kritischer Differenzialdiagnosen sowie in der Fläche noch wenig verzahnter Akutversorgungsstrukturen. Gleichwohl zeigen grundsätzlich die beim Erwachsenen etablierten Revaskularisationsstrategien auch beim Kind ihre möglichen, zum Teil spektakulären Erfolge. Es gilt also, diese nach Möglichkeit auch den betroffenen Kindern zur Verfügung zu stellen, auch wenn hier derzeit ein nicht annähernd vergleichbarer Grad an Evidenz erreicht ist. Postakut ist die ätiologische Aufarbeitung durch die größere Bandbreite zu bedenkender Risikofaktoren besonders komplex, muss aber in der Lage sein, das individuelle Risikoprofil mit Sekundärprophylaxe, Rezidivrisiko und Outcome präzise zu identifizieren. Die Langzeitbetreuung im multiprofessionellen, interdisziplinären Team muss die biopsychosozialen Aspekte des Kindes in seiner jeweiligen Entwicklungsphase berücksichtigen und damit eine bestmögliche Integration des Kindes in sein soziales und schulisches, später berufliches Umfeld realisieren.

Cerebral sinovenous thrombosis in children: A single-center experience

Objective

The study aimed to evaluate the patients with a diagnosis of cerebral sinovenous thrombosis in terms of clinical findings, etiology and underlying risk factors, imaging findings, treatment, and prognosis in the long term.

Materials and Methods

Medical records of 19 patients whose ages ranged between 0 days and 17 years with clinical and radiological cerebral sinovenous thrombosis in Ege University Department of Child Neurology were retrospectively evaluated.

Results

Nine of nineteen cases were female (47.3%). The median age was 84 months (0-201 months). The most common complaint at the presentation was headache (n=12) and the most common physical examination finding was papilledema (n=11). In etiology, otitis/mastoiditis in three cases, iron deficiency anemia in three cases, sinusitis in two cases, catheter use in four cases, Behçet's disease in three cases were determined. The most common observed genetic factors causing thrombosis was methylenetetrahydrofolate reductase mutation. The transverse sinus (68.4%) is the sinus where thrombosis is most frequently observed. As a result of an average follow-up of 12 months (2-72 months), hemiparesis (n=3/19, 15.7%) and epilepsy (n=5/19, 26.3%) were recorded as sequelae findings, and no mortality was observed.

Conclusion

In cases presenting with headache, evaluation of papilledema on funduscopic examination should not be skipped. Neurological imaging should be performed in the change of consciousness of poor feeding infants and children with infections in the head and neck area or underlying chronic diseases. When cerebral sinovenous thrombosis is detected, anticoagulant therapy should be started immediately.

[Childhood stroke : What are the special features of childhood stroke?]

Childhood arterial ischemic stroke differs in essential aspects from adult stroke. It is rare, often relatively unknown among laypersons and physicians and the wide variety of age-specific differential diagnoses (stroke mimics) as well as less established care structures often lead to a considerable delay in the diagnosis of stroke. The possible treatment options in childhood are mostly off-label. Experiences in well-established acute treatment modalities in adult stroke, such as thrombolysis and mechanical thrombectomy are therefore limited in children and only based on case reports and case series. The etiological clarification is time-consuming due to the multitude of risk factors which must be considered. Identifying each child's individual risk profile is mandatory for acute treatment and secondary prevention strategies and has an influence on the individual outcome. In addition to the clinical neurological outcome the residual neurological effects of stroke on cognition and behavior are decisive for the integration of the child into its educational, later professional and social environment.

Risk Factors for Perinatal Arterial Ischemic Stroke: A Case-Control Study

Introduction

Arterial ischemic stroke in newborns is an important cause of neonatal morbidity and mortality. Its pathophysiology and associated risk factors are not yet clearly understood and defined.

Objective

The aim of this retrospective study was to investigate possible risk factors in diagnosed cases of PAIS (perinatal arterial ischemic stroke).

Materials and methods

Case-control study. Clinical data of patients with PAIS diagnosis were analyzed. Two healthy controls were selected for each PAIS case, matched for gestational age. Risk factors were explored using univariable and multivariable analysis.

Outcome

40 patients were included in the study, 24 males and 16 females; 52.5% of cases were diagnosed within the first month of birth, and 47.5% were retrospectively diagnosed. The results showed a male predominance (66.7%). The distribution of cerebral ischemic injury was predominantly medial cerebral artery (87.5%) and occurred more commonly in the left cerebral hemisphere (62.5%). Significant risk factors in the univariate analysis (P < 0.05) were primiparity, stillbirth, neonatal sepsis, asphyxia, twin pregnancy, placenta abruption, emergency cesarean section, Apgar score ≤7 after 5 min, breech presentation, and hyperbilirubinemia. In the multivariate analysis, primiparity (OR 11.74; CI 3.28-42.02), emergency cesarean section (OR 13.79; CI 3.51-54.13), birth asphyxia (OR 40.55; CI 3.08-532.94) and Apgar score ≤7 after 5 min (OR 13.75; CI 1.03-364.03) were significantly associated factors with PAIS. Only five (16.6%) patients had an abnormal thrombophilia study.

Conclusion

Risk factors of primiparity, emergency cesarean section, birth asphyxia, and Apgar score ≤7 after 5 min were significantly associated with perinatal stroke. More studies with a larger number of patients and with prolonged follow up are required to establish more clearly the associated risk factors involved in this pathology.

Cerebral hemorrhagic infarction as the initial manifestation of deep venous thrombosis in a child with patent foramen ovale

Arterial ischemic stroke (AIS), with an estimated incidence of 1.1–4.3 per 100,000, is an important cause of morbidity and mortality in children and the risk of recurrence is high. We present the case of an 11-year-old child who presented with a symptomatology of acute ischemic stroke of unknown etiology. The radiological investigation did not reveal any underlying brain abnormality that could cause the event. The diagnostic work up included an echocardiogram, which revealed a thrombus in the right atrium, in conjunction with a patent foramen ovale. The patient was initiated immediately on anticoagulation therapy with low molecular weight heparin and warfarin, but two days later she suffered pulmonary emboli, diagnosed with spiral thorax computed tomography (CT) scan. An ultrasound study of the vessels of the lower extremitiesgcsp201817-main-client.xml revealed deep venous thrombosis (DVT), which was considered to be the underlying causative mechanism.

Association of Polymorphisms in Coagulation Factor Genes and Enzymes of Homocysteine Metabolism With Arterial Ischemic Stroke in Children

Despite the identification of a wide range of inherited and acquired risk factors for arterial ischemic stroke (AIS) in children, genetic risk factors are incompletely characterized and may vary among different populations. We investigated the role of individual and combined inherited prothrombotic and intermediate-risk factors in 73 children with perinatal (n = 35) and childhood AIS (n = 38) and 100 age- and sex-matched controls. Ten polymorphisms in 8 candidate genes encoding coagulation and fibrinolytic proteins (factor V [FV] Leiden, FV HR2, factor II [FII] G20210A, β-fibrinogen [β-FBG]-455G>A, factor XIII [FXIII]-A p.Val34Leu, plasminogen activator inhibitor 1 4G/5G), homocysteine metabolism (methylenetetrahydrofolate reductase [MTHFR] C677T, MTHFR A1298C), and intermediate-risk factors (angiotensin-converting enzyme I/D, apoE ∊2-4) were detected using a multilocus genotyping assay. Allele-specific polymerase chain reaction was used for the determination of human platelet alloantigens (HPA-1, HPA-2, HPA-3, and HPA-5). Factor V Leiden was associated with an increased risk of AIS (odds ratio [OR]: 4.72, 95% confidence interval [CI]: 1.22-18.27) and perinatal AIS (OR: 8.29, 95% CI: 1.95-35.24). Human platelet antigen-3b allele carriers had a 2-fold lower risk of AIS (OR: 0.51, 95% CI: 0.26-0.98) and perinatal AIS (OR: 0.40, 95% CI: 0.18-0.92). A 2.21-fold increased risk of childhood AIS (95% CI: 1.03-4.73) was identified in FXIII-A Leu34 allele carriers. Combined FV Leiden/FV HR2, FV Leiden/MTHFR A1298C, FV Leiden/MTHFR C677T/MTHFR A1298C, and FV Leiden/FV HR2/MTHFR A1298C heterozygosity was identified in children with AIS but not in controls, which revealed a statistically significant difference. This case-control study shows that besides already documented association between FV Leiden and AIS, other previously unreported polymorphisms (FXIII-A p.Val34Leu, HPA-3) and several genotype combinations that always include heterozygous FV Leiden can be related to AIS in Croatian population.

Patent foramen ovale and stroke in childhood: A systematic review of the literature

BACKGROUND

Stroke in association with a patent foramen ovale (PFO) may be due to paradoxical embolization via a right to left intracardiac shunt but the exact contribution of PFO to stroke or stroke recurrence in childhood remains unclear.

METHODS

To review the relationship of a PFO with stroke, and evaluate associated co-morbidities. An electronic database literature search of Pubmed, Cochrane and EMBASE was performed from January 2000-December 2014.

RESULTS

149 articles were retrieved, with overlap for diagnosis, management, treatment and outcome. 65 reports were utilized for the comprehensive review. Majority of childhood arterial ischemic stroke and transient ischemic attacks are associated with prothrombotic disorders or arteriopathy. Transthoracic echocardiography with a Valsalva maneuver is highly sensitive as a screening tool but may be falsely positive. Transthoracic echocardiography with color Doppler and a concurrent bubble contrast study are excellent for visualizing the atrial septum and PFO and identifying a right to left shunt. Current literature does not support PFO closure for cryptogenic stroke in young adults without an associated risk of thromboembolism.

CONCLUSIONS

High quality research in the pediatric population is lacking and most of the data is extrapolated from adults. Paradoxical embolism from a PFO as a cause of transient ischemic attack or stroke is a diagnosis of exclusion. PFO closure should be individualized based on significant shunting and risk factors such that maximum benefit is derived from the procedure. A young person with a PFO and stroke should be thoroughly investigated to rule out other etiologies.

Paediatric arterial ischemic stroke: acute management, recent advances and remaining issues

Stroke is a rare disease in childhood with an estimated incidence of 1-6/100.000. It has an increasingly recognised impact on child mortality along with its outcomes and effects on quality of life of patients and their families. Clinical presentation and risk factors of paediatric stroke are different to those of adults therefore it can be considered as an independent nosological entity. The relative rarity, the age-related peculiarities and the variety of manifested symptoms makes the diagnosis of paediatric stroke extremely difficult and often delayed. History and clinical examination should investigate underlying diseases or predisposing factors and should take into account the potential territoriality of neurological deficits and the spectrum of differential diagnosis of acute neurological accidents in childhood. Neuroimaging (in particular diffusion weighted magnetic resonance) is the keystone for diagnosis of paediatric stroke and other investigations might be considered according to the clinical condition. Despite substantial advances in paediatric stroke research and clinical care, many unanswered questions remain concerning both its acute treatment and its secondary prevention and rehabilitation so that treatment recommendations are mainly extrapolated from studies on adult population. We have tried to summarize the pathophysiological and clinical characteristics of arterial ischemic stroke in children and the most recent international guidelines and practical directions on how to recognise and manage it in paediatric emergency.

Transcranial Doppler Sonography in Pediatric Neurocritical Care: A Review of Clinical Applications and Case Illustrations in the Pediatric Intensive Care Unit

Transcranial Doppler sonography is a noninvasive, real-time physiologic monitor that can detect altered cerebral hemodynamics during catastrophic brain injury. Recent data suggest that transcranial Doppler sonography may provide important information about cerebrovascular hemodynamics in children with traumatic brain injury, intracranial hypertension, vasospasm, stroke, cerebrovascular disorders, central nervous system infections, and brain death. Information derived from transcranial Doppler sonography in these disorders may elucidate underlying pathophysiologic characteristics, predict outcomes, monitor responses to treatment, and prompt a change in management. We review emerging applications for transcranial Doppler sonography in the pediatric intensive care unit with case illustrations from our own experience.

Isolated midbrain ischemic infarct in association with hyperlipoproteinemia (a): a report of 2 adolescent patients

Arterial ischemic strokes (AIS) localized solely to the midbrain are extremely uncommon in the pediatric population. Elevated lipoprotein (a), which promotes atherosclerosis and a prothrombotic state, has been associated with increased risk of AIS in children and adults. Here we describe a 17-year-old boy and a 15-year-old girl who presented with internuclear ophthalmoplegia secondary to an isolated midbrain AIS. Evaluation for risk factors for AIS in these otherwise healthy adolescents identified hyperlipoproteinemia (a) in combination with other potential prothrombotic conditions suggesting that hypercoagulable states such as hyperlipoproteinemia (a) may have contributed to development of small-vessel arteriopathy and localized AIS.

Guidelines for the primary prevention of stroke: a statement for healthcare professionals from the American Heart Association/American Stroke Association

The aim of this updated statement is to provide comprehensive and timely evidence-based recommendations on the prevention of stroke among individuals who have not previously experienced a stroke or transient ischemic attack. Evidence-based recommendations are included for the control of risk factors, interventional approaches to atherosclerotic disease of the cervicocephalic circulation, and antithrombotic treatments for preventing thrombotic and thromboembolic stroke. Further recommendations are provided for genetic and pharmacogenetic testing and for the prevention of stroke in a variety of other specific circumstances, including sickle cell disease and patent foramen ovale.

The role of biochemical risk factors in the etiology of AIS in children and adults

Stroke is an abrupt onset of both focal and global neurological deficits secondary to a vascular event lasting more than 24 h and with a vascular background as its only cause. It can be triggered by a rupture of a blood vessel, aneurysm (hemorrhagic stroke, HS), thrombosis or embolisms (ischemic stroke, IS). In developed countries, it is the third most common cause of death in the adult population. Stroke in children is a rare disorder with a reported frequency of about 3 cases per 100,000 children per year. The history of acute brain ischemia is burdened with neurological complications such as motor impairment, speech impairment and intellectual delay. Moreover, in children after AIS seizures and epilepsy are also quite common. Stroke is a heterogeneous disorder; its risk factors in adults are well known, however, in pediatrics, in more than 20% cases, the cause of stroke is impossible to determine. Due to the fact that stroke usually arises as a consequence of the cerebral thrombosis, many of the mechanisms responsible for its occurrence can be considered as risk factors. We have reviewed the recent case-control studies conducted on pediatric patients regarding biochemical risk factors such as elevated levels of homocysteine, fibrinogen, protein C, protein S, antithrombin III, lipoprotein(a), cholesterol and its fractions, and compared them with the results obtained from adult patients.

Proteomic and biomarker studies and neurological complications of pediatric sickle cell disease

Biomarker analysis and proteomic discovery in pediatric sickle cell disease has the potential to lead to important discoveries and improve care. The aim of this review article is to describe proteomic and biomarker articles involving neurological and developmental complications in this population. A systematic review was conducted to identify relevant research publications. Articles were selected for children under the age of 21 years with the most common subtypes of sickle cell disease. Included articles focused on growth factors (platelet-derived growth factor), intra and extracellular brain proteins (glial fibrillary acidic protein, brain-derived neurotrophic factor), and inflammatory and coagulation markers (interleukin-1β, l-selectin, thrombospondin-1, erythrocyte, and platelet-derived microparticles). Positive findings include increases in plasma brain-derived neurotrophic factor and platelet-derived growth factor with elevated transcranial Dopplers velocities, increases in platelet-derived growth factor isoform AA with overt stroke, and increases in glial fibrillary acidic protein with acute brain injury. These promising potential neuro-biomarkers provide insight into pathophysiologic processes and clinical events, but their clinical utility is yet to be established. Additional proteomics research is needed, including broad-based proteomic discovery of plasma constituents and blood cell proteins, as well as urine and cerebrospinal fluid components, before, during and after neurological and developmental complications.

Cerebral Sinovenous Thrombosis in Children and Neonates

Our aim is to present the etiology and risk factors for cerebral sinovenous thrombosis (CSVT) and the radiological findings, anticoagulant therapy used, and treatment outcome of patients with CSVT. This study included 12 patients who were treated for CSVT at the Ankara University, School of Medicine, Department of Pediatric Neurology. This study included 5 girls (41.7%) and 7 boys (58.3%) with a mean age of symptom onset of 5.2 ± 6.29 years (range: 0-18 years), who were followed at our institution for a mean of 1.8 ± 1.73 years (range: 0-6.5 years). Among the patients, 3 had no risk factors, 2 had 1 risk factor, and 7 had multiple risk factors. Anticoagulant therapy was administered to 4 patients, of which 1 had neurological sequelae; neurological sequelae or exitus occurred in 4 of the 8 patients who did not receive anticoagulant therapy. The present findings showed that appropriate prophylaxis in appropriately selected patients reduced the rate of recurrence of CSVT.

Multiple presence of prothrombotic risk factors in Croatian children with arterial ischemic stroke and transient ischemic attack

Aim

To determine the frequency of inherited and acquired prothrombotic risk factors in children with arterial ischemic stroke (AIS) and transient ischemic attacks (TIA) in Croatia.

Methods

We investigated 14 prothrombotic risk factors using blood samples from 124 children with AIS or TIA and 42 healthy children. Prothrombotic risk factors were classified into five groups: natural coagulation inhibitors (antithrombin, protein C, protein S), blood coagulation factors (FV Leiden and FII 20210), homocysteine, lipid and lipoprotein profile (lipoprotein (a), triglycerides, total, high- and low-density lipoprotein), and antiphospholipid antibodies (lupus anticoagulant, anticardiolipin, and antiphosphatidylserine antibodies).

Results

The most common prothrombotic risk factor was elevated lipoprotein (a), which was identified in about 31% of patients and in 24% of controls. Natural coagulation inhibitors were decreased in about 19% of patients, but not in controls. Pathological values of homocysteine, blood coagulation factor polymorphisms, and antiphospholipid antibodies were found in similar frequencies in all groups. Fourteen children with AIS and TIA (11.3%) and no children from the control group had three or more investigated risk factors.

Conclusion

The presence of multiple prothrombotic risk factors in children with cerebrovascular disorder suggests that a combination of risk factors rather than individual risk factors could contribute to cerebrovascular disorders in children.

Factor V leiden and ischemic stroke risk: the Genetics of Early Onset Stroke (GEOS) study

BACKGROUND

Factor V Leiden (FVL) has been associated with ischemic stroke in children but not in adults. Although the FVL mutation is associated with increased risk for venous thrombosis, its association with ischemic stroke in young adults remains uncertain. Therefore, we examined the association between FVL and ischemic stroke in participants of the Genetics of Early Onset Stroke (GEOS) study.

METHODS

A population-based case control study identified 354 women and 476 men 15 to 49 years of age with first-ever ischemic stroke and 907 controls. Participant-specific data included vascular risk factors, FVL genotype and, for cases, the ischemic stroke subtype by modified Trial of ORG 10172 in Acute Stroke criteria. Logistic regression was used to calculate odds ratios for the entire population and for subgroups stratified by risk factors and ischemic stroke subtype.

RESULTS

The frequency of the FVL mutation was similar between ischemic stroke patients (3.6%; 95% confidence interval [CI] 2.5%-5.1%) and nonstroke controls (3.8%; 95% CI 2.7%-5.2%). This frequency did not change significantly when cases were restricted to patients with stroke of undetermined etiology (4.1%; 95% CI 2.6%-6.4%).

CONCLUSIONS

Among young adults, we found no evidence for an association between FVL and either all ischemic stroke or the subgroup with stroke of undetermined etiology.

A right-to-left shunt and prothrombotic disorders in pediatric patients presenting with transient ischemic attack

Arterial ischemic stroke is an important cause of morbidity and mortality in pediatric population. A right-to-left shunt (RLS) across the patent foramen ovale was recently demonstrated as a possible risk factor for pediatric stroke. Prothrombotic disorders are frequently identified in pediatric patients with stroke. Data regarding RLS and prothrombotic disorders in pediatric patients presenting with transient ischemic attack (TIA) are lacking. The aims of the present study were (1) to compare the prevalence and grade of RLS in pediatric patients presenting with TIA vs. controls using contrast transcranial Doppler with Valsalva maneuver and (2) to identify prothrombotic disorders in pediatric patients presenting with TIA. Twenty-three consecutive pediatric patients presenting with TIA were included in the study. Logistic regression analysis showed that RLS was significantly associated with TIA (OR 4.75, 95 % CI 1.39-16.2, p = 0.013). The prevalence of RLS was significantly higher in patients in comparison to controls (p = 0.019). Significantly more microembolic signals (MES) were detected in patients than in controls (p = 0.003). Prothrombotic disorders were identified in 14 of the 23 patients. Both the prevalence of RLS and number of detected MES were significantly higher in pediatric patients presenting with TIA in comparison to controls. Prothrombotic disorders were identified in a high proportion of patients. These findings suggest that paradoxical embolism may be important in pediatric patients presenting with TIA.

Inherited prothrombotic risk factors in children with first ischemic stroke

Stroke in children is a heterogeneous disorder. Over 100 risk factors for stroke have been reported and genetic predisposition to stroke has been established. The most frequently reported risk factors are congenital heart malformations, hemolytic anemias, collagen vascular diseases, some rare inborn metabolic disorders, trauma, infection and thrombophilia. The aim of this article is to provide an overview of investigated inherited prothrombotic risk factors in children with first ischemic stroke. Various prothrombotic risk factors have been investigated in pediatric stroke including elevated homocysteine and lipoprotein (a), antithrombin, protein C and protein S deficiency, Factor V Leiden, Factor II G20210A and plasminogen activator inhibitor-1 4G/5G polymorphism. Despite similar criteria for inclusion of different studies in meta-analyses investigating first ischemic stroke in children, the obtained results were not consistent for all prothrombotic risk factors. The discrepancies found could be explained by methodological issues like different sample sizes, patient populations included and lack of controls. In order to provide the necessary power for randomized control trials, multi-center, multi-national approaches like International Pediatric Stroke Study have been initiated with the aim to describe risk factors for childhood stroke and explore their relationship with presentation, age, geography, and infarct characteristics. Although it is evident from numerous studies that the frequency of inherited prothrombotic factors is increased in pediatric stroke, single thrombophilia does not fully explain stroke in a child as it represents only a mild risk factor. Further studies are needed, as improved understanding of underlying mechanisms will improve primary and secondary prevention of childhood stroke.

Nine kindreds of familial sticky platelet syndrome phenotype

INTRODUCTION

Sticky platelet syndrome (SPS) is most likely a hereditary thrombophilia characterized by platelet hyperaggregation after low concentrations of platelet inducers--adenosine diphosphate and/or epinephrine. We present 9 kindreds with SPS familial occurrence.

MATERIAL AND METHODS

Familial trait of SPS was looked up in the database of the National Center of Hemostasis and Thrombosis. Families with at least 3 SPS-positive members were studied, described, and presented.

RESULTS

In the group of 1093 symptomatic patients, SPS was confirmed in 240 cases. Familial occurrence with at least 3 SPS-positive relatives was found in 9 cases.

CONCLUSION

The exact pathogenesis of SPS is not sufficiently explained. Our findings seem to support the idea that SPS might have an autosomal dominant hereditary fashion.

Caring for cerebral venous sinus thrombosis in children

Cerebral venous sinus thrombosis in children is increasingly recognized as diagnostic tools and clinical awareness has improved. It is a multifactorial disease where prothrombotic risk factors and predisposing clinical conditions usually in combination constitute the underlying etiology. Clinical features range from headache, seizures to comatose state. Although symptomatic treatment involving control of infections, seizures and intracranial hypertension is uniform, use of anticoagulation and local thrombolytic therapy is still controversial. Morbidity and mortality can be significant and long-term neurological sequelae include developmental delay, sensorimotor and visual deficits and epilepsy.

[Infratentorial ischemic stroke in children: Three case reports]

Ischemic stroke is rare in children, most of which occur in the supratentorial brain, and infratentorial infarcts are very rare. Some clinical manifestations may be similar but others such as ataxia and cranial nerve palsy are more specific. Vertebral artery dissection is the most frequent cause of stroke in the vertebrobasilar territory, but the cause most often remains unknown in children. We report three cases of infratentorial stroke in children. The first observation concerns a 4-year-old boy brought to medical attention because left hemicorporal motor deficit associated with ataxia following a minor cranial traumatism. While computed tomography (CT) of the brain was normal, magnetic resonance imaging (MRI) revealed an area of signal alteration on the diffusion-weighted image within the right protuberance. The second observation is a 15-year-old girl who developed sudden-onset ataxia. The CT scan and MRI of the brain revealed an acute bilateral cerebellar stroke. MRI angiography showed an anatomical variant of the left vertebral artery that did not participate in the Willis polygon. In these two observations, no other abnormalities were detected except they were homozygotous for MTHFR mutation in the first observation and minor alpha-thalassemia for the second one. The outcome in these two children was good without sequelae after a 6-month follow-up. The third observation is a 6-year-old girl who suddenly exhibited cephalalgia, ataxia, and left visual impairment. The brain MRI revealed left occipital and cerebellar strokes due to vertebral artery dissection. The authors recommend the systematic search for vertebral artery dissection in cases of infratentorial stroke.

Paediatric arterial ischaemic stroke and cerebral sinovenous thrombosis in Denmark 1994-2006: a nationwide population-based study

AIM

To assess the incidence rates (IR), clinical characteristics, risk factors, treatment and outcomes of paediatric arterial ischaemic stroke (AIS) and cerebral sinovenous thrombosis (CSVT).

METHODS

Using population-based, nationwide medical registries, we identified all patients aged 0-18 years at the time of hospitalization with first-ever AIS and/or CSVT in Denmark between 1994 and 2006. Medical records were retrieved and reviewed.

RESULTS

We identified 211 patients with AIS and 40 patients with CSVT corresponding to IRs of 1.33 (95% CI 1.16-1.52) and 0.25 (95% CI 0.19-0.34) per 100,000 person-years, respectively. The IRs peaked in infancy (<1 year) for both AIS and CSVT with an additional peak among adolescents (15-18 years) for CSVT. The IR of AIS increased 3.9% per year (p=0.036), whereas no changes were found for CSVT. In total, 48.2% of the patients received antithrombotic treatment; no major complications were observed. All-cause and thrombosis-related 30-day case fatality ratios were 3.6% and 2.4%, respectively; neurological sequelae were found in 56.2% of patients.

CONCLUSION

The IR of AIS was highest in infants and had increased with 3.9% annually during the observation period. The IR of CSVT had an additional peak in adolescence and remained unchanged over time.

Current proceedings of childhood stroke

Stroke is a sudden onset neurological deficit due to a cerebrovascular event. In children, the recognition of stroke is often delayed due to the low incidence of stroke and the lack of specific assessment measures to this entity. The causes of pediatric stroke are significantly different from that of adult stroke. The lack of safety and efficiency data in the treatment is the challenge while facing children with stroke. Nearly half of survivors of pediatric stroke may have neurologic deficits affecting functional status and quality of life. They may cause a substantial burden on health care resources. Hence, an accurate history, including onset and duration of symptoms, risk factors, and a complete investigation, including hematologic, neuroimaging, and metabolic studies is the key to make a corrective diagnosis. A prompt and optimal treatment without delay may minimize the damage to the brain.

Imaging of nonaccidental injury and the mimics: issues and controversies in the era of evidence-based medicine

Because of the controversy involving the determination of child abuse, or nonaccidental injury (NAI), radiologists must be familiar with the issues, literature, and principles of evidence-based medicine to understand the role of imaging. Children with suspected NAI must receive protective evaluation along with a timely and complete clinical and imaging work-up. Imaging findings cannot stand alone and must be correlated with clinical findings, laboratory testing, and pathologic and forensic examinations. Only the child protection investigation may provide the basis for inflicted injury in the context of supportive clinical, imaging, biomechanical, or pathology findings.

Cerebral angiopathies as a cause of ischemic stroke in children: differential diagnosis and treatment options

BACKGROUND

Ischemic stroke in children can present with an epileptic seizure or be initially asymptomatic. The median time to diagnosis is 24 hours.

METHODS

This review is based on a selective literature search, with additional consideration of published guidelines and the authors' personal experience.

RESULTS

In Europe and the USA, the combined incidence of ischemic and hemorrhagic stroke in childhood is 2.5 to 10 per 100 000 children per year. 40% of ischemic strokes in childhood occur after an infectious illness or in association with a congenital heart defect, sickle-cell anemia, or a coagulopathy. Arterial dissection and chronic, progressive cerebral arteriopathies, particularly moyamoya disease, each account for up to 10% of childhood strokes. Magnetic resonance imaging can be used to demonstrate infarcts and to display the perfusion of ischemic areas and the surrounding brain tissue; arterial and venous occlusions can be defined more precisely. Children with arterial dissection, vasculitis, and para-infectious cerebral ischemia should be treated empirically, with medications and supportive care, according to the treatment plans developed for adults. For patients with moyamoya disease, surgical revascularization with extra-intracranial bypass techniques is recommended.

DISCUSSION

The current data provide an inadequate evidence base for the treatment of stroke in children. Potential revascularization or thrombolysis must be discussed individually in each case. For the treatment of temporary, para-infectious cerebral ischemia, hemodynamic optimization is an available option. Better evidence is needed regarding the surgical treatment of moyamoya disease.

Guidelines for the primary prevention of stroke: a guideline for healthcare professionals from the American Heart Association/American Stroke Association

BACKGROUND AND PURPOSE

This guideline provides an overview of the evidence on established and emerging risk factors for stroke to provide evidence-based recommendations for the reduction of risk of a first stroke.

METHODS

Writing group members were nominated by the committee chair on the basis of their previous work in relevant topic areas and were approved by the American Heart Association (AHA) Stroke Council Scientific Statement Oversight Committee and the AHA Manuscript Oversight Committee. The writing group used systematic literature reviews (covering the time since the last review was published in 2006 up to April 2009), reference to previously published guidelines, personal files, and expert opinion to summarize existing evidence, indicate gaps in current knowledge, and when appropriate, formulate recommendations using standard AHA criteria (Tables 1 and 2). All members of the writing group had the opportunity to comment on the recommendations and approved the final version of this document. The guideline underwent extensive peer review by the Stroke Council leadership and the AHA scientific statements oversight committees before consideration and approval by the AHA Science Advisory and Coordinating Committee.

RESULTS

Schemes for assessing a person's risk of a first stroke were evaluated. Risk factors or risk markers for a first stroke were classified according to potential for modification (nonmodifiable, modifiable, or potentially modifiable) and strength of evidence (well documented or less well documented). Nonmodifiable risk factors include age, sex, low birth weight, race/ethnicity, and genetic predisposition. Well-documented and modifiable risk factors include hypertension, exposure to cigarette smoke, diabetes, atrial fibrillation and certain other cardiac conditions, dyslipidemia, carotid artery stenosis, sickle cell disease, postmenopausal hormone therapy, poor diet, physical inactivity, and obesity and body fat distribution. Less well-documented or potentially modifiable risk factors include the metabolic syndrome, excessive alcohol consumption, drug abuse, use of oral contraceptives, sleep-disordered breathing, migraine, hyperhomocysteinemia, elevated lipoprotein(a), hypercoagulability, inflammation, and infection. Data on the use of aspirin for primary stroke prevention are reviewed.

CONCLUSIONS

Extensive evidence identifies a variety of specific factors that increase the risk of a first stroke and that provide strategies for reducing that risk.

Factor V Leiden and prothrombin 20210G>A [corrected] mutation and paediatric ischaemic stroke: a case-control study and two meta-analyses

AIM

To determine whether factor V Leiden (FVL) and prothrombin (PT) 20210G>A mutation are associated with paediatric ischaemic stroke.

METHODS

The study consisted of two parts. Case-control study included neuroradiologically confirmed paediatric ischaemic stroke patients from two tertiary children's hospitals in Estonia. For control group, DNA was obtained from 400 anonymous screening test cards of newborns born consecutively in all delivery departments of Estonia in January 2005. Meta-analyses was performed to assess the association between paediatric sinovenous thrombosis and FVL and PT 20210G>A.

RESULTS

A total of 75 children (45 boys, 30 girls) were included into the case-control study: 19 with childhood arterial ischaemic stroke, 49 with perinatal arterial ischaemic stroke and seven with cerebral venous thrombosis. Both FVL and PT 20210G>A occurred significantly more frequently among patients with sinovenous thrombosis compared with controls (OR = 12.9; 95% CI: 2.3-73.0 and OR = 11.9; 95% CI: 2.1-67.2, respectively). The difference was not significant between childhood/perinatal arterial ischaemic stroke and controls. Meta-analyses (including our study) revealed that both FVL and PT 20210G>A are associated with paediatric sinovenous thrombosis (OR = 3.1; 95% CI: 1.8-5.5 and OR = 3.1; 95% CI: 1.4-6.8, respectively).

CONCLUSION

FVL and PT 20210G>A are associated with paediatric sinovenous thrombosis.

Meta-analysis of factor V Leiden and ischemic stroke in young adults: the importance of case ascertainment

BACKGROUND AND PURPOSE

The factor V Leiden mutation is associated with ischemic stroke in children but not in adults. Whether it is associated with ischemic stroke in young adults, however, is uncertain.

METHODS

To address this issue, we performed a meta-analysis of 18 case-control studies of ischemic stroke in adults 50 years of age and younger published before June 2009.

RESULTS

Across all studies, factor V Leiden was detected in 154 of 2045 cases (7.5%) and 217 of 5307 controls (4.1%), yielding a fixed-effect odds ratio of 2.00 (95% CI, 1.59-2.51). However, further analyses revealed substantial heterogeneity among these studies (P=0.005 for Q-test of heterogeneity). Hypothesizing that this heterogeneity could be related to differences among studies in case selection criteria, we stratified the meta-analysis into studies for which case samples were enriched or not enriched to include cases having an increased likelihood of prothrombotic genetic involvement ("selected" ischemic stroke studies, n=9) and those that recruited cases from consecutive neurology referrals or hospitalizations ("unselected" ischemic stroke studies, n=8). Among the 9 "selected" ischemic stroke studies, factor V Leiden was more strongly associated with stroke (OR, 2.73; 95% CI, 1.98-3.75), whereas among the 8 "unselected" ischemic stroke studies, the association between factor V Leiden and stroke was substantially weaker (OR, 1.40; 95% CI, 0.998-1.95). This difference was found to be statistically significant (P=0.003 for Woolf test for heterogeneity).

CONCLUSIONS

We conclude that factor V Leiden is associated with ischemic stroke in young adults, particularly in patient populations in which there is an increased clinical suspicion of prothrombotic state.

Thrombosis in the pediatric population

Whereas thrombotic events in critically ill children do not occur as commonly as in adults, they are being recognized with increasing frequency in the pediatric intensive care unit. The reasons for this are not clear but likely include an increased awareness of the problem and the ability to make a diagnosis using relatively noninvasive tests. In this section, I attempt to define the extent of the problem, summarize and discuss the relevant literature (pointing out where published experience in the pediatric population differs from that in adult patients), and suggest some guidelines regarding thrombophilia treatment and the management of thrombotic events.

Crossing the blood-brain barrier: clinical interactions between neurologists and hematologists in pediatrics - advances in childhood arterial ischemic stroke and cerebral venous thrombosis

PURPOSE OF REVIEW

The past year has marked a period of growing awareness of the need for improved diagnosis and treatment in children with arterial ischemic stroke (AIS) and cerebral sinus venous thrombosis (CSVT). Here we review these conditions, highlighting the importance of the intersection between hematologic abnormalities and pediatric stroke as they impact clinical management.

RECENT FINDINGS

Recent multicenter cohort studies are beginning to clarify the incidence, risk factors, clinical course and outcomes of AIS and CSVT in children. Key findings include: diagnosis rests on adequate neuroimaging and is often delayed more than 24 h after symptom onset; multiple risk factors and inciting events are often involved; one or more prothrombotic risk factors are common; recurrence is common; and selected groups of patients benefit from anticoagulation, and less frequently, thrombolytic therapies.

SUMMARY

Progress in caring for children with AIS and CSVT requires greatly improved awareness of cerebrovascular disease among primary providers, who are most often the first point of contact, more rapid and specific diagnosis using appropriate advanced neuroimaging technologies, comprehensive hematologic evaluation for inherited and acquired thrombophilias, and multidisciplinary approaches to treatment. Additional large cohort studies and clinical trials are greatly needed to further clarify these issues.

Methylenetetrahydrofolate reductase gene polymorphism and childhood stroke

Genotyping for the methylenetetrahydrofolate reductase gene (MTHFR) has been recommended for part of the evaluation for underlying prothrombotic state in childhood stroke; however, studies are inconclusive regarding the role of this gene and also the role of hyperhomocysteinemia, which is the putative mechanism by which MTHFR polymorphism is related to stroke. The prevalence of MTHFR polymorphism in childhood arterial ischemic stroke and cerebral sinovenous thrombosis was compared with that of a reference population, and prevalence of hyperhomocysteinemia was reviewed. In arterial ischemic stroke, the prevalence of at-risk methylenetetrahydrofolate reductase genotypes was 27%, and in cerebral sinovenous thrombosis it was 13%; the population prevalence was 26%. The odds ratio for at-risk genotype in childhood arterial ischemic stroke was 1.06 (95% confidence interval, 0.22-4.0); in cerebral sinovenous thrombosis, it was 0.42 (95% confidence interval, 0.01-3.6). No tested cases had hyperhomocysteinemia. MTHFR polymorphism and hyperhomocysteinemia were not risk factors in childhood arterial ischemic stroke or cerebral sinovenous thrombosis in the Intermountain West region.

Elevated levels of soluble P-selectin in mice alter blood-brain barrier function, exacerbate stroke, and promote atherosclerosis

Cerebrovascular and cardiovascular diseases are a major cause of morbidity and mortality. Soluble P-selectin (sP-selectin) is a biomarker for platelet/endothelial activation and is considered a risk factor for vascular disease. sP-selectin enhances procoagulant activity by inducing leukocyte-derived microparticle production and promotes activation of leukocyte integrins. However, it is not known whether it directly contributes to vascular complications. We investigated the effect of increased levels of sP-selectin on blood-brain barrier (BBB) function, stroke outcome, and atherosclerosis by comparing wild-type mice with P-sel(DeltaCT/DeltaCT) mice in which the endogenous P-selectin gene was replaced with a mutant that produces abnormally high plasma levels of sP-selectin. P-sel(DeltaCT/DeltaCT) mice presented several abnormalities, including (1) higher BBB permeability, with 25% of the animals showing differential permeability between the right and left hemispheres; (2) altered social behavior with increased aggression; (3) larger infarcts in the middle cerebral artery occlusion ischemic stroke model; and (4) increased susceptibility to atherosclerotic, macrophage-rich lesion development in both male and female mice on the apoE(-/-) genetic background. Thus, elevated sP-selectin is not only a biomarker for vascular disease, but also may contribute directly to atherosclerosis and cerebrovascular complications.

Inherited prothrombotic risk factors in children with stroke, transient ischemic attack, or migraine

OBJECTIVE

The aim of this study was to investigate the prevalence and possible association of inherited prothrombotic risk factors in children with stroke, transient ischemic attack, or migraine.

METHODS

We performed genotypic analysis for factor V G1691A, factor II G20210A, methylenetetrahydrofolate reductase C677T, and 4 common platelet glycoprotein polymorphisms (human platelet alloantigen-1, -2, -3, and -5) in 150 children <18 years of age with established diagnoses of stroke, transient ischemic attack, or migraine. Children were classified into 5 groups, namely, childhood arterial ischemic stroke (N = 33), perinatal arterial ischemic stroke (N = 26), hemorrhagic stroke (N = 20), transient ischemic attack (N = 36), and migraine (N = 35). The control group consisted of 112 children < or =18 years of age from the same geographical region who had no history of neurologic or thromboembolic diseases.

RESULTS

Heterozygosity for factor V G1691A was associated with approximately sevenfold increased risk for arterial ischemic stroke, perinatal arterial ischemic stroke, and transient ischemic attack. Increased risk for transient ischemic attack was found in carriers of the human platelet alloantigen-2b allele, human platelet alloantigen-5a/b genotype, and combined human platelet alloantigen-2b and human platelet alloantigen-5b genotype. The presence of the human platelet alloantigen-2b allele was associated with a 2.23-fold increased risk for migraine, whereas carriers of the human platelet alloantigen-3b allele had a lower risk for arterial ischemic stroke than did carriers of the human platelet alloantigen-3a allele.

CONCLUSIONS

Factor V G1691A has an important role in susceptibility to arterial ischemic stroke, both in the perinatal/neonatal period and in childhood, as well as transient ischemic attacks. A minor impact of human platelet alloantigen polymorphisms suggests that platelet glycoprotein polymorphisms may increase the risk of transient ischemic attacks and migraine, but this should be confirmed in larger studies.

Advances in perinatal ischemic stroke

Increasingly distinct patterns of focal ischemic injury in the fetal and perinatal brain are recognized. Improved classification has afforded advances in risk factor identification, pathophysiology hypotheses, outcome prediction, and potential avenues for intervention. Cerebrovascular occlusion leading to perinatal stroke may be arterial or venous, symptomatic or subclinical, and it can occur across multiple time frames. Distinguishing causative factors from mere associations represents a major challenge with important implications for studies of pathogenesis. The adverse outcomes suffered by most children highlight the need for further research. Reviewed here are the current understandings, recent advancements, and future directions for research in perinatal ischemic stroke.

Pediatric antiphospholipid syndrome: clinical and immunologic features of 121 patients in an international registry

OBJECTIVES

The purpose of this study was to obtain data on the association of antiphospholipid antibodies with clinical manifestations in childhood and to enable future studies to determine the impact of treatment and long-term outcome of pediatric antiphospholipid syndrome.

PATIENTS AND METHODS

A European registry extended internationally of pediatric patients with antiphospholipid syndrome was established as a collaborative project of the European Antiphospholipid Antibodies Forum and Lupus Working Group of the Pediatric Rheumatology European Society. To be eligible for enrollment the patient must meet the preliminary criteria for the classification of pediatric antiphospholipid syndrome and the onset of antiphospholipid syndrome must have occurred before the patient's 18th birthday.

RESULTS

As of December 1, 2007, there were 121 confirmed antiphospholipid syndrome cases registered from 14 countries. Fifty-six patients were male, and 65 were female, with a mean age at the onset of antiphospholipid syndrome of 10.7 years. Sixty (49.5%) patients had underlying autoimmune disease. Venous thrombosis occurred in 72 (60%), arterial thrombosis in 39 (32%), small-vessel thrombosis in 7 (6%), and mixed arterial and venous thrombosis in 3 (2%). Associated nonthrombotic clinical manifestations included hematologic manifestations (38%), skin disorders (18%), and nonthrombotic neurologic manifestations (16%). Laboratory investigations revealed positive anticardiolipin antibodies in 81% of the patients, anti-beta(2)-glycoprotein I antibodies in 67%, and lupus anticoagulant in 72%. Comparisons between different subgroups revealed that patients with primary antiphospholipid syndrome were younger and had a higher frequency of arterial thrombotic events, whereas patients with antiphospholipid syndrome associated with underlying autoimmune disease were older and had a higher frequency of venous thrombotic events associated with hematologic and skin manifestations.

CONCLUSIONS

Clinical and laboratory characterization of patients with pediatric antiphospholipid syndrome implies some important differences between antiphospholipid syndrome in pediatric and adult populations. Comparisons between children with primary antiphospholipid syndrome and antiphospholipid syndrome associated with autoimmune disease have revealed certain differences that suggest 2 distinct subgroups.

Cryptogenic stroke in a boy with atrial septal defect and hyperhomocysteinemia

In children, clinical recognition of stroke and determination of its exact etiology are extremely difficult. The authors described a case of cryptogenic stroke in a 14-year-old-boy with asymptomatic atrial septal defect and hypercoagulable state. Paradoxical embolism was hypothesized as the responsible etiopathological mechanism. It is crucial to increase clinician awareness of stroke in children.