Cerebrovascular disease and stroke

Risk factors for pediatric ischemic stroke and intracranial hemorrhage: A national electronic health record based study

Background

Stroke is an important cause of morbidity in pediatrics. Large studies are needed to better understand the epidemiology, pathogenesis and risk factors associated with pediatric stroke. Large administrative datasets can provide information on risk factors in perinatal and childhood stroke at low cost. The aim of this hypothesis-generating study was to use a large administrative dataset to assess for prevalence and odds-ratios of rare exposures associated with pediatric stroke.

Methods

The data for patients aged 0-18 with a diagnosis of either ischemic stroke or intracranial hemorrhage were extracted from the Cerner Health Facts EMR Database from 2000 to 2018. Prevalence of various possible risk factors for pediatric and adult stroke was assessed using ICD 9 and 10 codes. Odds ratios were calculated using a control group of patients without stroke.

Results

10,688 children were identified with stroke. 6339 (59 %) were ischemic and 4349 (41 %) were hemorrhagic. The most frequently identified risk factors for ischemic stroke across age groups were hypertension (29-44 %), trauma (19-33 %), and malignancy (11-24 %). The most common risk factors seen with hemorrhagic stroke were trauma (32-64 %), malignancy (5-19 %) and arrhythmia (9-12 %). Odds ratios across all age groups for dyslipidemia (17-64), hypertension (20-63), and tobacco exposure (3-59) were high in the ischemic stroke cohort.

Conclusion

This is the largest retrospective study of pediatric stroke of its kind from hospitals across the US in both academic and non-academic clinical settings. Much of our data was consistent with prior studies. ICD codes for tobacco exposure, hyperlipidemia, diabetes, and hypertension all had high odds ratios for stroke in children, which suggest a relationship between these conditions and pediatric stroke. However, ascertainment bias is a major concern with electronic health record-based studies. More focused study is needed into the role of these exposures into the pathogenesis of pediatric stroke.

A critical review on brain and heart axis response in COVID-19 patients: Molecular mechanisms, mediators, biomarkers, and therapeutics

Since the outbreak of highly virulent coronaviruses, significant interest was assessed to the brain and heart axis (BHA) in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-affected patients. The majority of clinical reports accounted for unusual symptoms associated with SARS-CoV-2 infections which are of the neurological type, such as headache, nausea, dysgeusia, anosmia, and cerebral infarction. The SARS-CoV-2 enters the cells through the angiotensin-converting enzyme (ACE-2) receptor. Patients with prior cardiovascular disease (CVD) have a higher risk of COVID-19 infection and it has related to various cardiovascular (CV) complications. Infected patients with pre-existing CVDs are also particularly exposed to critical health outcomes. Overall, COVID-19 affected patients admitted to intensive care units (ICU) and exposed to stressful environmental constraints, featured with a cluster of neurological and CV complications. In this review, we summarized the main contributions in the literature on how SARS-CoV-2 could interfere with the BHA and its role in affecting multiorgan disorders. Specifically, the central nervous system involvement, mainly in relation to CV alterations in COVID-19-affected patients, is considered. This review also emphasizes the biomarkers and therapy options for COVID-19 patients presenting with CV problems.

Novel wine in an old bottle: Preventive and therapeutic potentials of andrographolide in atherosclerotic cardiovascular diseases

Atherosclerotic cardiovascular disease (ASCVD) frequently results in sudden death and poses a serious threat to public health worldwide. The drugs approved for the prevention and treatment of ASCVD are usually used in combination but are inefficient owing to their side effects and single therapeutic targets. Therefore, the use of natural products in developing drugs for the prevention and treatment of ASCVD has received great scholarly attention. Andrographolide (AG) is a diterpenoid lactone compound extracted from Andrographis paniculata. In addition to its use in conditions such as sore throat, AG can be used to prevent and treat ASCVD. It is different from drugs that are commonly used in the prevention and treatment of ASCVD and can not only treat obesity, diabetes, hyperlipidaemia and ASCVD but also inhibit the pathological process of atherosclerosis (AS) including lipid accumulation, inflammation, oxidative stress and cellular abnormalities by regulating various targets and pathways. However, the pharmacological mechanisms of AG underlying the prevention and treatment of ASCVD have not been corroborated, which may hinder its clinical development and application. Therefore, this review summarizes the physiological and pathological mechanisms underlying the development of ASCVD and the in vivo and in vitro pharmacological effects of AG on the relative risk factors of AS and ASCVD. The findings support the use of the old pharmacological compound ('old bottle') as a novel drug ('novel wine') for the prevention and treatment of ASCVD. Additionally, this review summarizes studies on the availability as well as pharmaceutical and pharmacokinetic properties of AG, aiming to provide more information regarding the clinical application and further research and development of AG.

Retinoic Acid Prevents the Neuronal Damage Through the Regulation of Parvalbumin in an Ischemic Stroke Model

Ischemic stroke is a neurological disease that causes brain damage by increasing oxidative stress and ion imbalance. Retinoic acid is a major metabolite of vitamin A and regulates oxidative stress, calcium homeostasis, and cell death. Intracellular calcium is involved in neuronal growth and synaptic plasticity. Parvalbumin is a calcium-binding protein that is mainly expressed in brain. In this study, we investigated whether retinoic acid has neuroprotective effects by controlling intracellular calcium concentration and parvalbumin expression in ischemic brain damage. Middle cerebral artery occlusion (MCAO) was performed to induce cerebral ischemia. Retinoic acid (5 mg/kg) or vehicle was injected into the abdominal cavity for four days before surgery and cerebral cortices were collected 24 h after MCAO for further studies. MCAO damage induced neurological deficits and histopathological changes and decreased parvalbumin expression. However, retinoic acid treatment alleviated these changes. In cultured neurons, glutamate (5 mM) exposure induced neuronal cell death, increased intracellular calcium concentration, and decreased parvalbumin expression. Retinoic acid treatment attenuated these changes against glutamate toxicity in a dose-dependent manner. It also regulates glutamate induced change in bcl-2 and bax expression. The mitigation effects of retinoic acid were greater under non-transfection conditions than under parvalbumin siRNA transfection conditions. Our findings showed that retinoic acid modulates intracellular calcium concentration and parvalbumin expression and prevents apoptosis in ischemic brain injury. In conclusion, retinoic acid contributes to the preservation of neurons from ischemic stroke by controlling parvalbumin expression and apoptosis-related proteins.

Kawasaki Disease May Increase the Risk of Subsequent Cerebrovascular Disease

BACKGROUND AND PURPOSE

Previous epidemiological investigations examining the association between Kawasaki disease (KD) and cerebrovascular disease have had conflicting results. We analyzed the association between KD and cerebrovascular disease by conducting a population-based retrospective cohort study designed to investigate the hypothesis that KD could be a risk factor for subsequent cerebrovascular disease.

METHODS

From the National Health Insurance Research Database of Taiwan, the data of children (aged 0-18 years old) with KD (n=8467) were collected. Starting with the first year of study observation (referred to as the baseline year), data was collected for each child with KD, and 4 non-KD patients matched for sex, urbanization level of residence, and parental occupation were randomly selected to form the non-KD cohort (n=33 868) for our analysis. For the period from January 1, 2000, to December 31, 2012, we calculated the follow-up person-years for each patient, which is the time from the index date to the diagnosis of cerebrovascular disease, death, or the end of 2012. Furthermore, we compared the incidence, the incidence rate ratio, and the 95% CI of cerebrovascular disease between the KD and non-KD cohorts.

RESULTS

The overall cerebrovascular disease incidence rate was found to be 3.19-fold higher, which is significantly higher, in the KD cohort than in the non-KD cohort (14.73 versus 4.62 per 100 000 person-years), and the overall risk of cerebrovascular disease remained higher in the KD cohort (adjusted hazard ratio, 3.16 [95% CI, 1.46-6.85]). Furthermore, children aged <5 years showed a significantly higher risk of subsequent cerebrovascular disease in the KD cohort (adjusted hazard ratio, 3.14 [95% CI, 1.43-6.92]).

CONCLUSIONS

This nationwide retrospective cohort study shows that KD may increase the risk of subsequent cerebrovascular disease, especially in those with KD aged <5 years old.

Chlorogenic acid alleviates neurobehavioral disorders and brain damage in focal ischemia animal models

Cerebral ischemia leads to neuronal cell death, causes neurological disorder and permanent disability. Chlorogenic acid has antioxidant, anti-inflammatory, and anti-apoptotic properties. This study investigated the neuroprotective effects of chlorogenic acid against cerebral ischemia. Focal cerebral ischemia was induced in male adult rats via middle cerebral artery occlusion (MCAO). Chlorogenic acid (30 mg/kg) or vehicle was injected in the intraperitoneal cavity 2 h after MCAO operation. Neurological behavior tests were performed 24 h after MCAO, brain edema and infarction were measured. Oxidative stress was assessed by investigating the levels of reactive oxygen species (ROS) and lipid peroxidation (LPO) levels. MCAO damage leaded to severe neurobehavioral deficits, increased ROS and LPO levels, and induced brain edema and infarction. MCAO damage caused histopathological damages and increased the number of terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL)-positive cells in the cerebral cortex. However, chlorogenic acid treatment improved neurological behavioral deficits caused by MCAO and attenuated the increase in ROS and LPO levels. It also alleviated MCAO-induced brain edema, infarction, and histopathological lesion. Chlorogenic acid treatment attenuated the increase in the number of TUNEL-positive cells in the cerebral cortex of MCAO animals. We also investigated caspase proteins expression to elucidate the neuroprotective mechanism of chlorogenic acid. Caspase-3, caspase-7, and poly ADP-ribose polymerase expression levels were increased in the MCAO damaged cortex, while chlorogenic acid mitigated these increases. These results showed that MCAO injury leads to severe neurological damages and chlorogenic acid exerts neuroprotective effects by regulating oxidative stress and caspase proteins expressions. Thus, our findings suggest that chlorogenic acid acts as a potent neuroprotective agent by modulating the apoptotic-related proteins.

Short-term neurological outcomes in ischemic and hemorrhagic pediatric stroke

BACKGROUND

The aim of this study was to retrospectively assess short-term neurological outcomes in pediatric stroke with regard to patient characteristics.

METHODS

Children aged 28 days-18 years with arterial ischemic stroke (AIS), cerebral sinovenous thrombosis (CSVT), and hemorrhagic stroke (HS) between 2007 and 2013 were evaluated. Neurological findings in the first 3 months were accepted as short-term prognosis, and modified Rankin scale was used.

RESULTS

A total of 33 patients (62%) with AIS, 12 (23%) with HS, and eight (15%) with CSVT were included. Moya moya syndrome was the most common new diagnosis in AIS. Stroke recurred in five (15%); and one AIS patient with posterior circulation infarct died (3%). Prognosis in AIS was favorable for 20 patients (61%) and poor for 13 patients (39%). Forty-two percent of HS were of vascular origin. Seven patients (70%) with HS had good prognosis and three (30%) had poor prognosis with no death. Homocysteine-related hypercoagulability was most frequently noted in the etiology of CSVT. Synchronous systemic thrombosis was observed in three CSVT patients (37.5%) and death occurred in two (25%). Prognosis was evaluated as favorable for three CSVT patients (37.5%) and poor for five (62.5%). For thrombophilia, thrombosis panel was performed fully in 83% of AIS and CSVT patients.

CONCLUSIONS

Pediatric stroke is associated with a poor prognosis in a substantial number of patients in the short term, with CSVT having the worst prognosis. Detailed patient characteristics are listed not only for ischemic but also for hemorrhagic stroke; and a full thrombosis panel was achieved for most ischemic stroke patients.

Pediatric Arterial Ischemic Stroke: Clinical Presentation, Risk Factors, and Pediatric NIH Stroke Scale in a Series of Chilean Patients

Stroke is an important cause of morbidity and mortality in children. Clinical presentation is diverse, and multiple risk factors have been described. The aim of this retrospective study is to describe the clinical presentation, risk factors, and the Pediatric National Institute of Health Stroke Scale (PedNIHSS) in a series of pediatric Chilean patients with the diagnosis of arterial ischemic stroke (AIS). Children diagnosed with AIS aged between 29 d and 18 y were enrolled (1989 to 2016). Clinical characteristics and risk factors were described. PedNIHSS severity score was estimated for patients older than 4 mo of age. Sixty-two patients were included, 66% were male, and the mean age of presentation was 3.5 y. Seventy-nine percent presented motor deficit, 45% seizures, and 15% consciousness impairment. Eighty-two percent had a unilateral stroke and 73% had anterior circulation territory affected. The main risk factors were arteriopathy (63%) and infection (43%). The PedNIHSS mean was 7.6, ranging between 0 and 17. In the categories in which it was possible to apply χ² test, only the acute systemic conditions category was statistically significant (P = 0.03), being higher in the group of patients younger than 3 y old. We confirmed male predominance in AIS and the most frequent presenting symptom was motor deficit. We found at least 1 risk factor in all patients with complete information. We confirmed arteriopathy as the most frequent risk factor, and acute systemic conditions were higher in patients younger than 3 y old with statistical significance (P = 0.03). The majority of patients presented mild to moderate severity in the PedNIHSS score.

[Cerebral infarction related to varicella zoster virus vasculopathy]

A 14-year-old girl developed transient disturbance of consciousness, dysarthria, and clumsiness of the right upper limb 4 months after herpes zoster ophthalmicus. Brain MRI showed acute cerebral infarction in the left middle cerebral artery (MCA) territory. CT angiography demonstrated mild stenosis in the top of the left internal carotid artery and the proximal side of the MCA. Cerebrospinal fluid (CSF) examination showed slightly mononuclear pleocytosis (6/μl). Titer of the anti-varicella zoster virus (VZV) IgG antibodies in CSF was increased, and gadolinium-enhanced brain MRI (T₁-weighted imaging) revealed enhancement of the vessel walls at the stenotic lesions. Based on the diagnosis of VZV vasculopathy, methylprednisolone and valacicrovir were administered, followed by acyclovir, in addition to antithrombotic therapy using aspirin and warfarin. After these treatment, her right upper clumsiness was resolved and gadolinium-enhancement of the vessel walls was disappeared on MRI. VZV vasculopathy may cause ischemic stroke in young patients, especially in children. A careful history-taking about herpes is necessary to detect the disease as a potential cause in young stroke patients.

A pictorial review of imaging in paediatric stroke

Stroke is recognised as an important disease in adults. Paediatric stroke is less understood, yet still an important cause of morbidity and mortality, with an incidence of 5 per 100 000 children and is one of the top 10 leading causes of death in children. In adults the vast majority of strokes are ischaemic, whereas in children haemorrhage makes up half the cases. The incidence of neonatal stroke is much higher, at up to 45 per 100 000 population; however, the underlying causes are less understood. This paper acts as a guide to the different causes of stroke with the key differences on imaging discussed.

Iron Deficiency Anemia Prevalence at First Stroke or Transient Ischemic Attack

Background:

Iron deficiency anemia (IDA) has been implicated in the etiology of transient ischemic attack and ischemic stroke. This study aimed to: 1) document IDA prevalence in patients ≥ 65 years of age admitted to hospital with transient ischemic attack or first ischemic stroke, and 2) investigate dietary intake as a predictor of iron status.

Methods:

Ninety-four patients were enrolled. An algorithm containing values for hemoglobin, ferritin, total iron binding capacity, transferrin saturation, and serum transferrin receptor measured at admission was used to identify IDA. Usual dietary intake was assessed with the Clue II food frequency questionnaire.

Results:

Prevalence estimates were 6.4% for IDA, 2.1% for iron deficiency without anemia, and 6.4% for anemia from other causes. IDA prevalence was significantly higher than published National Health and Nutrition Examination Survey III (NHANES III) estimates for gender-specific age groups ≥ 70 years (One-Sample Proportion Test; males p = 0.038 [n= 37]; females p = 0.002 [n=44]). A comparison of IDA prevalence against selected controls from the NHANES III database yielded an odds ratio (OR) of 6.3, 95% confidence interval (CI) 0.8 to 53.7, which was not statistically significant (Fisher's Exact Test; n=94; p = 0.118). Multivariate linear regression analysis of dietary intake with indicators of iron status (n=58) revealed only iron supplements (p = 0.013) and heme iron intake (p = 0.038) as negative predictors of total iron binding capacity (p<0.05).

Conclusions:

These findings support the initiation of a prospective case control study to investigate IDA as a risk factor for ischemic stroke in elderly patients.

Small-animal PET demonstrates brain metabolic change after using bevacizumab in a rat model of cerebral ischemic injury

To evaluate the effect of bevacizumab on cerebral ischemia, we used 2-deoxy-2-(18)F-fluoro-D-glucose ((18)F-FDG) small-animal positron emission tomography (PET) in the middle cerebral artery occlusion (MCAO) rat model. After baseline neurologic function tests and PET studies, MCAO Sprague-Dawley rats received bevacizumab or normal saline (controls). Weekly PET imaging and neurologic function tests showed that the (18)F-FDG accumulation in the bevacizumab group was similar to that in the controls during the first 2 weeks, but lower than in controls at weeks 3 and 4. However, no difference was found in neurological scores between the groups. The number of von Willebrand factor-positive cells in the bevacizumab group was lower than that in controls. The expression of vascular endothelial growth factor was higher than in controls at week 4. These results suggested that bevacizumab does not influence functional recovery in this model of cerebral ischemia during a 4-week period, but inhibits vascular formation and metabolic recovery, which may be considered in cancer patients with a recent ischemic stroke.

Cognitive outcomes following arterial ischemic stroke in infants and children

This study sought to investigate cognitive outcomes following pediatric arterial ischemic stroke and explore predictors. Participants included 36 children with perinatal or childhood arterial ischemic stroke and a comparison group of 15 children with asthma. Outcomes included cognitive ability, executive functions, and neurological function (Pediatric Stroke Outcome Measure). Magnetic resonance imaging measured lesion location and volume. Mean cognitive scores were at the low end of the average range. Children with arterial ischemic stroke performed significantly below normative populations and significantly below the asthma group on inhibitory control (Cohen's d = .68). Both the Pediatric Stroke Outcome Measure and lesion volume were negatively correlated with cognitive outcome (Spearman r = -.01 to -.42 Pediatric Stroke Outcome Measure; r =-.14 to -.32 Volume). Following arterial ischemic stroke, children performed at the low end of the average range on measures of cognitive functioning. Cognitive outcomes depend on a variety of factors.

Childhood stroke: results of 130 children from a reference center in Central Anatolia, Turkey

BACKGROUND

Although stroke among children is rare, it can cause significant morbidity and mortality. We aim to share our experience of children with arterial ischemic stroke.

METHODS

The initial symptoms, demographical features, risk factors, neurological examination, neuroradiological findings, and clinical follow-up data of 130 Turkish children seen between 2002 and 2013 were retrospectively analyzed.

RESULTS

Sixty-eight patients were male. Thirty of the children were aged from 1 to 12 months (seven of them died in this period). Focal neurological signs were the most common presentation, and hemiplegia or hemiparesis were the most common focal signs. Underlying risk factors were detected in 103 patients. Infections and congenital heart disease were the most common risk factors. Seven of the nine children with recurrent arterial ischemic strokes had one or more underlying diseases (moyamoya disease in two children along with factor V Leiden mutation, tuberculous meningitis, congenital heart disease, homocystinuria, and hemiconvulsion-hemiplegia-epilepsy syndrome). The arterial ischemic stroke was located in the middle cerebral circulation in 68 (36 left and 32 right) and in the posterior cerebral artery in 41. Eighteen children died. The neurological outcome was assessed in 98 children. Of these children, 66 children have neurological deficits and 52 children have seizures. Stroke in the first year of life is more often fatal. Recurrent stroke is associated with poor prognosis.

CONCLUSION

Tuberculous meningitis is still a risk factor for arterial ischemic stroke in Turkey. Arterial ischemic stroke in the first year of life and recurrent arterial ischemic stroke represent poor prognostic features.

Inherited thrombophilia in pediatric ischemic stroke: an Egyptian study

Pediatric stroke is relatively uncommon, with often subtle clinical presentations. Numerous predisposing risk factors can be both inherited and acquired, including cardiac disease, vascular abnormalities, infectious diseases, collagen tissue diseases, inborn errors of metabolism, anticardiolipin antibody, lupus anticoagulant, deficiencies of protein C, protein S, antithrombin, or plasminogen, and prothrombotic mutations. We explored risk factors, clinical features, and neuroimaging among Egyptian children with ischemic stroke, and estimated the prevalence of inherited thrombophilia. We included 20 children with ischemic stroke, recruited from the Pediatric Neurology Outpatient Clinic (Ain Shams University). Basic clinical evaluations for stroke and genotyping for factor V 1691 G-A (factor V Leiden), prothrombin 20210 G-A mutations, and methylenetetrahydrofolate reductase 677 C-T polymorphisms were performed using real-time polymerase chain reaction, with fluorescent melting curve detection analysis. Ten patients (50%) manifested methylenetetrahydrofolate reductase polymorphisms (six homozygotes and four heterozygotes). Heterozygous factor V Leiden was present in five (25%), whereas prothrombin mutation was present in only one (5%). Five patients (25%) manifested combined prothrombotic abnormalities. Thirteen demonstrated evidence of inherited thrombophilic disorder; 25% manifested more than one mutation. For appropriate risk assessment, even in the presence of overt acquired thrombotic risk factors, physicians should request complete thrombophilia screening for patients with stroke.

[Experts' recommendations: stroke management in the intensive care unit. Pediatric specificities (excluding neonates)]

Stroke in children is not rare. Although there are no randomized trials on childhood stroke, except in sickle cell disease patients, several international guidelines have described quality criteria for stroke management in children. Age-adapted management is required, involving collaboration with a pediatric neurologist and hospitalization in a pediatric intensive care or continuous care unit. All symptomatic treatments used in adults can be recommended in children, including homeostasis assessment and maintenance or blood exchange in sickle cell disease patients. Specific treatments such as thrombolysis or mechanical thrombectomy are not recommended in children, except in the framework of clinical trials, but can be beneficial in adolescents. Multidisciplinary decision-making should be the rule in such situations. Adolescents may be managed in adult stroke units. Indications for surgery in children are adapted from adult guidelines. Appropriate management of cerebral venous thrombosis in children is similar to that in adults. The best management possible can be achieved through a multidisciplinary dialogue between the pediatric neurologist and the adult intensivist or neurologist.

Cerebrovascular disease and stroke in Korean male adolescent

PURPOSE

This study aimed to estimate the prevalence and incidence of cerebrovascular disease (CVD) and stroke in Korean male adolescents.

MATERIALS AND METHODS

The authors reviewed all medical certificates, medical records, and radiologic images from the examinations of Korean military conscription from January 2008 to May 2011.

RESULTS

Of the 101,156 examinees, 40 had CVD and stroke during adolescence. The overall prevalence and incidence of CVD and stroke was 39.54 cases per 100,000 adolescents and 2.08 cases per 100,000 adolescents per year, respectively and these were similar to the worldwide data. There were 3 cases of aneurysm, 3 cases of dural arteriovenous fistula, 11 cases of arteriovenous malformation, 4 cases of cavernous hemangioma, 4 cases of cerebrovascular infarction, 16 cases of Moyamoya disease, and 1 case of missing data. The incidence of arteriovenous malformation (0.57 cases per 100,000 adolescents per year) was lower than the incidence for the worldwide general population. The incidence of Moyamoya disease was higher than that in any other country (15.82 cases per 100,000 adolescents, vs. 0.83 cases per 100,000 adolescents per year).

CONCLUSION

We observed ischemic and hemorrhagic stroke, each accounting for approximately half of cases, and high incidence of Moyamoya disease with low incidence of arteriovenous malformation in Korean male adolescents.

The role of imaging studies for evaluation of stroke in children

Stroke is a major cause of morbidity and mortality in children and long-term neurological deficits. Although cerebrovascular disorders occur less often in children than in adults, recognition of stroke in children has probably increased because of the widespread application of noninvasive diagnostic studies such as magnetic resonance imaging and computed tomography.Computed tomography (CT) should be the first imaging choice in the emergency setting when stroke is suspected. It will show the presence of hemorrhage (eg, bleeding from arteriovenous malformation). It is often normal within the first hours in arterial ischemic stroke. As in adults, magnetic resonance imaging is the neuroimaging modality to confirm the clinical diagnosis of ischemic stroke. In children, however, magnetic resonance imaging requires sedation and may not be as readily available as CT. Perfusion imaging demonstrates flow within the brain and can detect areas that are at risk of ischemia; however, further studies in the pediatric population need to be validated for this technique in children. Angiography detects arterial disease (eg, aneurysm); however, its use has been largely superseded by better magnetic resonance angiography, which is sensitive enough to visualize lesions in the proximal anterior cerebral artery, middle cerebral artery, and distal internal carotid artery (ICA). Magnetic resonance imaging using diffusion- weighted imaging is the most versatile and sensitive imaging technique for identifying ischemic lesions. In the future, we need to identify the pediatric patient presenting to the emergency department with an acute stroke and develop a pathway for the use of particular imaging techniques (eg, CT vs magnetic resonance imaging).

Thromboembolism in pediatric inflammatory bowel disease: systematic review

BACKGROUND

Several studies suggest an increased risk of venous and arterial thromboembolism (TE) in adults with inflammatory bowel disease (IBD) compared to the general population. We performed a systematic review of studies on incidence and characteristic of TE in children with IBD.

METHODS

We searched Medline, LILACS, EMBASE, POPLINE, CINHAL, and reference lists of identified articles, without language restrictions, in August 2010.

RESULTS

Population studies suggest that there is an increased risk of TE in children with IBD compared to controls. TE occurred in children with IBD in all age ranges, mostly (82.8%) during active disease, and more frequently in children with ulcerative colitis (odds ratio [OR] 3.7, 95% confidence interval [CI] 1.8-7.6). At least one specific risk factor for TE was recognized in 50% of cases; two risk factors were present in 24%. Out of 92 published cases of TE in children with IBD, 54.3% occurred in cerebral site, 26% in the limbs, 13% in the abdominal vessels, and the remaining in the retina and lungs. After a first episode of TE, an early recurrence was observed in 11.4% of children, a late recurrence in 10%. A number of different therapeutic schemes were used. Overall mortality was 5.7% and was mostly associated with cerebral TE.

CONCLUSIONS

Population studies are needed to clarify the risk of TE in children with IBD, the relative weight of other risk factors, the characteristics of the events, and to define guidelines of therapy and prophylaxis.

Inherited thrombophilia in childhood arterial stroke: data from Lebanon

Pediatric ischemic stroke still represents a burden, and more than half of the survivors will experience cognitive or motor disabilities. The objective of this study was to investigate the role of thrombophilia in a cohort of children with arterial ischemic stroke. The records of infants and children with clinically and radiologically confirmed stroke were reviewed. Patients with venous or perinatal stroke were not included. Thirty-three patients were diagnosed with arterial ischemic stroke. The male/female ratio was 1.75:1. The median age was 4 years. The most frequent clinical manifestations were hemiparesis (54.5%) and seizures (33.3%). Genetic thrombophilia testing was available on 24 patients. Nine of the 24 patients (37.5%) were heterozygous for factor V Leiden. None of the patients carried the factor II G20210A variant. Ten patients (41.7%) were heterozygous and 3 (12.5%) were homozygous for methylenetetrahydrofolate reductase (MTHFR) C677T variant. Fifteen patients (62.5%) had one or more genetic polymorphism. Factor V Leiden was significantly associated with arterial ischemic stroke (P < 0.001). Stroke recurred in 2 children with multiple risk factors and MTHFR C677T mutation. Factor V Leiden is one of the major genetic risk factors for pediatric arterial ischemic stroke in Lebanon. MTHFR C677T was prevalent among patients with recurrent stroke.

Ischemic stroke in infants and children: practical management in emergency

Stroke is a rare disease in children, with an estimated incidence 13/100000 and a significant impact on morbidity and mortality. Clinical presentation and risk factors, present in almost half of pediatric patients, are not the same as in adults. The diagnosis of stroke in children is often delayed because signs and symptoms can be subtle and nonspecific. History and clinical examination should exclude underlying diseases or predisposing factors. Neuroimaging is crucial in defining diagnosis. Other tests might be necessary, according to the clinical picture. We present here the most recent practical directions on how to diagnose and manage arterial stroke in children, according to different international guidelines on the subject.

Current concepts in the management of stroke in children with sickle cell disease

Stroke is the most significant complication of sickle cell disease (SCD) in children with the potential for major morbidity and mortality. The recent two decades have witnessed tremendous advancements in understanding the pathophysiology of stroke, risk stratification of children and the role of timely preventative interventions. The aetiopathogenesis, types of stroke and specific risk factors are reviewed here with special emphasis on the role of transcranial Doppler ultrasonogram in the early identification of at-risk children. Published studies on primary and secondary prevention of stroke in children with SCD are analysed with respect to the levels of evidence, in favour of preventative and therapeutic strategies. The roles of the neurologist and the neurosurgeon are highlighted.

Homozygous mutation in SAMHD1 gene causes cerebral vasculopathy and early onset stroke

We describe an autosomal recessive condition characterized with cerebral vasculopathy and early onset of stroke in 14 individuals in Old Order Amish. The phenotype of the condition was highly heterogeneous, ranging from severe developmental disability to normal schooling. Cerebral vasculopathy was a major hallmark of the condition with a common theme of multifocal stenoses and aneurysms in large arteries, accompanied by chronic ischemic changes, moyamoya morphology, and evidence of prior acute infarction and hemorrhage. Early signs of the disease included mild intrauterine growth restriction, infantile hypotonia, and irritability, followed by failure to thrive and short stature. Acrocyanosis, Raynaud's phenomenon, chilblain lesions, low-pitch hoarse voice, glaucoma, migraine headache, and arthritis were frequently observed. The early onset or recurrence of strokes secondary to cerebral vasculopathy seems to always be associated with poor outcomes. The elevated erythrocyte sedimentation rate (ESR), IgG, neopterin, and TNF-α found in these patients suggested an immune disorder. Through genomewide homozygosity mapping, we localized the disease gene to chromosome (Chr) 20q11.22-q12. Candidate gene sequencing identified a homozygous mutation, c.1411-2A > G, in the SAMHD1 gene, being associated with this condition. The mutation appeared at the splice-acceptor site of intron 12, resulted in the skipping of exon 13, and gave rise to an aberrant protein with in-frame deletion of 31 amino acids. Immunoblotting analysis showed lack of mutant SAMHD1 protein expression in affected cell lines. The function of SAMHD1 remains unclear, but the inflammatory vasculopathies of the brain found in the patients with SAMHD1 mutation indicate its important roles in immunoregulation and cerebral vascular hemeostasis.

Childhood stroke in Sweden I: incidence, symptoms, risk factors and short-term outcome

AIM

To evaluate the incidence, presenting symptoms, diagnostic delay, risk factors and short-term outcome of childhood stroke in a population-based cohort of Swedish children.

METHODS

We retrospectively reviewed the records of children experiencing their first stroke during a 7-year period in Uppsala-Örebro Health Care Region covering one-fifth of the Swedish population. Arterial ischaemic stroke (AIS), cerebral sinus venous stroke and nontraumatic haemorrhagic stroke (HS) in children aged > 28 days and < 18 years were included.

RESULTS

We identified 51 children (23 boys and 28 girls; median age 13). The average annual incidence of stroke was 1.8 per 100,000 children. AIS was found in 51% of the children, HS in 41% and cerebral sinus venous stroke in 8%. One-third of the children had underlying diseases, and one-third had vascular malformations. Six girls used oral contraceptives, three of these were smokers and two had iron deficiency anaemia. Two children died in the acute stage (4%), and 40/49 (82%) had some neurological dysfunction at discharge.

CONCLUSION

The incidence of childhood stroke was 1.8 per 100,000 children and year, and the primary mortality was 4%. Risk factors of importance were oral contraceptives, smoking and anaemia in combinations.

Stroke in early childhood due to homocystinuria

A previously healthy girl, age 3 years 9 months, presented with right-sided hemiparesis and seizures. Ischemic infarction was confirmed through magnetic resonance imaging and magnetic resonance angiography. Extensive evaluation to discover the underlying etiologies and risk factors predisposing this patient to stroke included coagulation defects, cardiac anomalies, congenital inborn metabolism deficiency, and infections and trauma. Based on the clinical and laboratory results, a diagnosis of homocystinuria was made. Homocystinuria is an inherited disorder that affects the metabolism of the amino acid methionine. Although homocystinuria is usually associated with ischemic strokes, the sudden onset of stroke as the initial clinical presentation of homocystinuria is very rare in early childhood. Based on this case, however, metabolic screening for hyperhomocystinemia is recommended in any child presenting with a stroke.

Cerebrovascular complications in pediatric intensive care unit

Cerebrovascular complications are being frequently recognized in the pediatric intensive care unit in the recent few years. The epidemiology and risk factors for pediatric stroke are different from that of the adults. The incidence of ischemic stroke is almost slightly more than that of hemorrhagic stroke. The list of diagnostic causes is increasing with the availability of newer imaging modalities and laboratory tests. The diagnostic work up depends on the age of the child and the rapidity of presentation. Magnetic resonance imaging, computerized tomography and arteriography and venography are the mainstay of diagnosis and to differentiate between ischemic and hemorrhagic events. Very sophisticated molecular diagnostic tests are required in a very few patients. There are very few pediatric studies on the management of stroke. General supportive management is as important as the specific treatment. Most of the treatment guidelines and suggestions are extrapolated from the adult studies. Few guidelines are available for the use of anticoagulants and thrombolytic agents in pediatric patients. So, our objective was to review the available literature on the childhood stroke and to provide an insight into the subject for the pediatricians and critical care providers.

The epidemiology of childhood stroke

This paper reviews the epidemiology of childhood stroke. Stroke is an important condition in children. It is one of the top ten causes of childhood death and there is a high risk of serious morbidity for the survivors. Epidemiological data are an integral part of disease understanding and high quality studies are required to ensure that this data is robust. Incidence rates from population-based studies vary from 1.3 per 100,000 to 13.0 per 100,000. Factors found to influence incidence rates include age, gender, and ethnicity but there are also many inherent differences between studies. Temporal analysis of mortality rates from childhood stroke shows falling rates but there has been little long-term study of changes in incidence rates. Improved epidemiological data should be a goal of the national and international collaborative networks that are studying childhood stroke.

Epidemiology of childhood stroke in Estonia

We investigated the incidence and 30-day case-fatality of childhood stroke in Estonia, and clinical signs and risk factors of childhood stroke. A retrospective (1995-2003) and prospective study (2004-2006) of childhood stroke (arterial ischemic, hemorrhagic, and sinovenous thrombosis) and transient ischemic attack was conducted. Stroke-incidence calculation was based on the prospective study. Clinical diagnoses of stroke were confirmed by neuroradiology. The incidence rate of childhood stroke in Estonia was 2.73/100,000 person-years for children aged 30 days to 18 years: 1.61/100,000 for arterial ischemic stroke, 0.87/100,000 for hemorrhagic stroke, 0.25/100,000 for sinovenous thrombosis, and 0.37/100,000 for transient ischemic attack. No arterial ischemic stroke patients died within 30 days, but case-fatality for intracerebral hemorrhage was 46%. Focal signs occurred in 100% of arterial ischemic strokes and 64% of intracerebral hemorrhage cases. Risk factors were identified in 35/48 (73%) children with cerebrovascular attacks. Six children with arterial ischemic stroke (6/24, 25%) manifested more than one risk factor. The incidence rate of childhood stroke in Estonia is similar to that in earlier data.

New Alzheimer amyloid beta responsive genes identified in human neuroblastoma cells by hierarchical clustering

Alzheimer's disease (AD) is characterized by neuronal degeneration and cell loss. Aβ₄₂, in contrast to Aβ₄₀, is thought to be the pathogenic form triggering the pathological cascade in AD. In order to unravel overall gene regulation we monitored the transcriptomic responses to increased or decreased Aβ₄₀ and Aβ₄₂ levels, generated and derived from its precursor C99 (C-terminal fragment of APP comprising 99 amino acids) in human neuroblastoma cells. We identified fourteen differentially expressed transcripts by hierarchical clustering and discussed their involvement in AD. These fourteen transcripts were grouped into two main clusters each showing distinct differential expression patterns depending on Aβ₄₀ and Aβ₄₂ levels. Among these transcripts we discovered an unexpected inverse and strong differential expression of neurogenin 2 (NEUROG2) and KIAA0125 in all examined cell clones. C99-overexpression had a similar effect on NEUROG2 and KIAA0125 expression as a decreased Aβ₄₂/Aβ₄₀ ratio. Importantly however, an increased Aβ₄₂/Aβ₄₀ ratio, which is typical of AD, had an inverse expression pattern of NEUROG2 and KIAA0125: An increased Aβ₄₂/Aβ₄₀ ratio up-regulated NEUROG2, but down-regulated KIAA0125, whereas the opposite regulation pattern was observed for a decreased Aβ₄₂/Aβ₄₀ ratio. We discuss the possibilities that the so far uncharacterized KIAA0125 might be a counter player of NEUROG2 and that KIAA0125 could be involved in neurogenesis, due to the involvement of NEUROG2 in developmental neural processes.

Novel multi-modal strategies to promote brain and spinal cord injury recovery

Stroke is the leading cause of disability in the United States, and yet no definitive interventions can drive the nervous system beyond its measurable but often limited spontaneous recovery. Treatment to limit injury progression and enhance repair after stroke or other types of central nervous system injury is complicated by the heterogeneous nature of cell death and wound healing mechanisms and the multiple barriers to functional recovery. The heterogeneity of injury and repair mechanisms requires interventions that are broad and multi-modal, but also intrinsically safe. We describe a process to identify such interventions by screening multiple individual targets in the historically separate realms of neuroprotection, repair, and regeneration against a library of FDA-approved compounds with known safety. We have identified nearly 10 compounds that are able to activate simultaneously protective and reparative genes. These compounds have a theoretical therapeutic window that spans from evolving injury (minutes to hours) to stable injury (days to months to years). It is our hypothesis that these compounds will be most efficacious when paired with training. The notion is that drugs will alter the propensity of the nervous system toward recovery, whereas specific training will engage the needed instructive cues to achieve this goal. Indeed, robotic training can provide a level of motor learning that seems to enhance the salutary effects of training. In a system that depends heavily on cells that do not easily replenish themselves, cellular therapies could also ultimately be an important part of the cocktail. We conclude that combinations of interventions will be needed to surmount the multiple barriers to recovery in stroke and other types of brain and spinal cord injury recovery.