Central nervous system vasculitis in children:

Towards a histological diagnosis of childhood small vessel CNS vasculitis

BACKGROUND

Primary small vessel CNS vasculitis (sv-cPACNS) is a challenging inflammatory brain disease in children. Brain biopsy is mandatory to confirm the diagnosis. This study aims to develop and validate a histological scoring tool for diagnosing small vessel CNS vasculitis.

METHODS

A standardized brain biopsy scoring instrument was developed and applied to consecutive full-thickness brain biopsies of pediatric cases and controls at a single center. Stains included immunohistochemistry and Hematoxylin & Eosin. Nine North American neuropathologists, blinded to patients' presentation, diagnosis, and therapy, scored de-identified biopsies independently.

RESULTS

A total of 31 brain biopsy specimens from children with sv-cPACNS, 11 with epilepsy, and 11 with non-vasculitic inflammatory brain disease controls were included. Angiocentric inflammation in the cortex or white matter increases the likelihood of sv-cPACNS, with odds ratios (ORs) of 3.231 (95CI: 0.914-11.420, p = 0.067) and 3.923 (95CI: 1.13-13.6, p = 0.031). Moderate to severe inflammation in these regions is associated with a higher probability of sv-cPACNS, with ORs of 5.56 (95CI: 1.02-29.47, p = 0.046) in the cortex and 6.76 (95CI: 1.26-36.11, p = 0.025) in white matter. CD3, CD4, CD8, and CD20 cells predominated the inflammatory infiltrate. Reactive endothelium was strongly associated with sv-cPACNS, with an OR of 8.93 (p = 0.001). Features reported in adult sv-PACNS, including granulomas, necrosis, or fibrin deposits, were absent in all biopsies. The presence of leptomeningeal inflammation in isolation was non-diagnostic.

CONCLUSION

Distinct histological features were identified in sv-cPACNS biopsies, including moderate to severe angiocentric inflammatory infiltrates in the cortex or white matter, consisting of CD3, CD4, CD8, and CD20 cells, alongside reactive endothelium with specificity of 95%. In the first study of its kind proposing histological criteria for evaluating brain biopsies, we aim to precisely characterize the type and severity of the inflammatory response in patients with sv-cPACNS; this can enable consolidation of this population to assess outcomes and treatment methodologies comprehensively.

Primary central nervous system vasculitis and headache: Ten themes

PURPOSE OF REVIEW

The primary central nervous system (CNS) vasculitides refers to clinicopathologic disorders that share the histopathology of inflammation of cerebral or spinal blood vessels. Unrecognized and therefore untreated, vasculitis of the CNS results in irreversible injury and disability making these disorders of paramount importance to clinicians.

RECENT FINDINGS

Headache is an important clue to vasculitic involvement of CNS vessels. CNS vasculitis can be primary, in which only intracranial or spinal vessels are involved in the inflammatory process, or secondary to another known disorder with overlapping systemic involvement. The suspicion of vasculitis based on the history, clinical examination, and laboratory studies warrants prompt evaluation and treatment to prevent cerebral ischemia or infarction.

SUMMARY

Primary CNS vasculitides can be diagnosed with certainty after intensive evaluation that includes tissue confirmation whenever possible. As in its systemic counterparts, clinicians must choose from among the available immune modulating, suppressive, and targeted immunotherapies to induce and maintain remission status and prevent relapse, tempered by anticipated medication adverse effects.

Identification of Central Nervous System Oncologic Disease Biomarkers in EVs from Cerebrospinal Fluid (CSF) of Pediatric Patients: A Pilot Neuro-Proteomic Study

Cerebrospinal fluid (CSF) is a biochemical-clinical window into the brain. Unfortunately, its wide dynamic range, low protein concentration, and small sample quantity significantly limit the possibility of using it routinely. Extraventricular drainage (EVD) of CSF allows us to solve quantitative problems and to study the biological role of extracellular vesicles (EVs). In this study, we implemented bioinformatic analysis of our previous data of EVD of CSF and its EVs obtained from congenital hydrocephalus with the aim of identifying a comprehensive list of potential tumor and non-tumor biomarkers of central nervous system diseases. Among all proteins identified, those enriched in EVs are associated with synapses, synaptosomes, and nervous system diseases including gliomas, embryonal tumors, and epilepsy. Among these EV-enriched proteins, given the broad consensus present in the recent scientific literature, we validated syntaxin-binding protein 1 (STXBP1) as a marker of malignancy in EVD of CSF and its EVs from patients with pilocytic astrocytoma and medulloblastoma. Our results show that STXBP1 is negatively enriched in EVs compared to non-tumor diseases and its downregulation correlates with adverse outcomes. Further experiments are needed to validate this and other EV markers in the blood of pediatric patients for translational medicine applications.

Small vessel childhood primary angiitis of the central nervous system with positive anti-glial fibrillary acidic protein antibodies: a case report and review of literature

BACKGROUND

Small vessel childhood primary angiitis of the central nervous system (SV-cPACNS) is a rare disease characterized by inflammation within small vessels such as arterioles or capillaries.

CASE PRESENTATION

We report a case of SV-cPACNS in an 8-year-old boy confirmed by brain biopsy. This patient was also incidentally found to have anti-glial fibrillary acidic protein (GFAP) antibodies in the cerebrospinal fluid (CSF) but had no evidence of antibody-mediated disease on brain biopsy. A literature review highlighted the rarity of SV-cPACNS and found no prior reports of CSF GFAP-associated SV-cPACNS in the pediatric age group.

CONCLUSION

We present the first case of biopsy proven SV-cPACNS vasculitis associated with an incidental finding of CSF GFAP antibodies. The GFAP antibodies are likely a clinically insignificant bystander in this case and possibly in other diseases with CNS inflammation. Further research is needed to determine the clinical significance of newer CSF autoantibodies such as anti-GFAP before they are used for medical decision-making in pediatrics.

Adult and childhood vasculitis

Vasculitis refers to heterogeneous clinicopathologic disorders that share the histopathology of inflammation of blood vessels. Unrecognized and therefore untreated, vasculitis of the nervous system leads to pervasive injury and disability, making this a disorder of paramount importance to all clinicians. There has been remarkable progress in the pathogenesis, diagnosis, and treatment of primary CNS and PNS vasculitides, predicated on achievement in primary systemic forms. Primary neurological vasculitides can be diagnosed with assurance after intensive evaluation that incudes tissue confirmation whenever possible. Clinicians must choose from among the available immune modulating, suppressive, and targeted immunotherapies to induce and maintain remission status and prevent relapse, unfortunately without the benefit of RCTs, and tempered by the recognition of anticipated medication side effects. It may be said that efforts to define a disease are attempts to understand the very concept of the disease. This has been especially evident in systemic and neurological disorders associated with vasculitis. For the past 100 years, since the first description of granulomatous angiitis of the brain, the CNS vasculitides have captured the attention of generations of clinical investigators around the globe to reach a better understanding of vasculitides involving the central and peripheral nervous system. Since that time it has become increasingly evident that this will necessitate an international collaborative effort.

Motor sequela of adult and pediatric stroke: Imminent losses and ultimate gains

Stroke is the leading cause of neurological disability in the United States and worldwide. Remarkable advances have been made over the past 20 years in acute vascular treatments to reduce infarct size and improve neurological outcome. Substantially less progress has been made in the understanding and clinical approaches to neurological recovery after stroke. This chapter reviews the epidemiology, bedside examination, localization approaches, and classification of stroke, with an emphasis on motor stroke presentations and management, and promising research approaches to enhancing motor aspects of stroke recovery.

Central and Peripheral Nervous System Complications of Vasculitis Syndromes From Pathology to Bedside: Part 1-Central Nervous System

PURPOSE OF REVIEW

The aim of this review is to provide a comprehensive update on the clinical assessment, diagnosis, complications, and treatment of primary central nervous system vasculitis (PCNSV).

RECENT FINDINGS

The developments in neuroimaging, molecular testing, and cerebral biopsy have enhanced clinical assessment and decision making, providing novel insights to prevent misdiagnosis increasing diagnostic certainty. Advances in imaging techniques visualizing the wall of intracranial vessels have improved the possibility to distinguish inflammatory from non-inflammatory vascular lesions. Large recent studies have revealed a more varied histopathological pictures and disclosed an association with amyloid angiopathy. Unfortunately, therapy remains largely empiric. PCNSV is a heterogeneous group of disorders encompassing different clinical subsets that may differ in terms of prognosis and therapy. Recent evidence has described a more benign course, with good response to therapy. New diagnostic techniques will play soon a pivotal role in the appropriate diagnosis and prompt management of PCNSV.

The Role of Pediatric Rheumatologists in Autoimmune Brain Disease

The spectrum of autoimmune and inflammatory brain diseases continues to evolve with medical advances facilitating both the detection of inflammation of the central nervous system and the discovery of novel disease mechanisms. The clinical overlap of these disorders with primary rheumatic diseases and the efficacy of immunotherapy have led to strong partnerships between pediatric rheumatologists, neurologists, psychiatrists, and other providers in the care of children with these conditions. Early diagnosis and initiation of targeted therapy improve clinical outcomes, highlighting the importance of interdisciplinary collaborative care.

Granulomatous Angiitis: Twenty Years Later

Granulomatous inflammation, the prototypical histopathology of adult and childhood vasculitis, is characterized by inflammation of blood vessels accompanied by giant cells and epithelioid cells in the walls of cerebral vessels ranging from small leptomeningeal veins to large named cerebral arteries. Headache, hemiparesis, mental changes, abnormal cerebrospinal fluid protein content, and pleocytosis are suggestive features that warrant brain and leptomeningeal biopsy to make the diagnosis certain and begin cytotoxic therapy to improve outcome.

Treatment of Vasculitis of the Nervous System

The diagnosis of primary central and peripheral nerve vasculitides should be established with certainty if suspected before commencing potent immunosuppressive therapy. The aim of induction therapy is to rapidly control the underlying inflammatory response and stabilize the blood-brain and blood-nerve barriers, followed by maintenance immunosuppression tailored to the likeliest humoral and cell-mediated autoimmune inflammatory vasculitic processes.

Health-related quality of life in children with inflammatory brain disease

OBJECTIVE

To quantify the impact of inflammatory brain diseases in the pediatric population on health-related quality of life, including the subdomains of physical, emotional, school and social functioning.

METHODS

This was a multicenter, observational cohort study of children (< 18 years of age) diagnosed with inflammatory brain disease (IBrainD). Patients were included if they had completed at least one Health Related Quality of Life Questionnaire (HRQoL). HRQoL was measured using the Pediatric Quality of Life Inventory Version 4.0 (PedsQL) Generic Core Scales, which provided a total score out of 100. Analyses of trends were performed using linear regression models adjusted for repeated measures over time.

RESULTS

In this study, 145 patients were included of which 80 (55%) were females. Cognitive dysfunction was the most common presenting symptoms (63%), and small vessel childhood primary angiitis of the CNS was the most common diagnosis (33%). The mean child's self-reported PedsQL total score at diagnosis was 68.4, and the mean parent's proxy-reported PedsQL score was 63.4 at diagnosis. Child's self-reported PedsQL scores reflected poor HRQoL in 52.9% of patients at diagnosis. Seizures or cognitive dysfunction at presentation was associated with statistically significant deficits in HRQoL.

CONCLUSION

Pediatric IBrainD is associated with significantly diminished health-related quality of life. Future research should elucidate why these deficits occur and interventions should focus on improving HRQoL in the most affected subdomains, in particular for children presenting with seizures and cognitive dysfunction.

A homozygote TREX1 mutation in two siblings with different phenotypes: Chilblains and cerebral vasculitis

Three prime repair exonuclease 1 degrades single and double stranded DNA with 3'-5' nuclease activity and its mutations are related to type 1 IFN mediated autoinflammation due to accumulated intracellular nucleic acids. To date, several cases of systemic lupus erythematosus, Aicardi-Goutieres syndrome, familial chilblain lupus, retinal vasculopathy-cerebral leukodystrophy have been reported with TREX1 mutations. Chilblain lupus is a skin disease characterized by blue-reddish coloring, swelling or ulcers on acral regions of body such as fingertips, heels, nose and auricles. Central nervous system vasculitis is a prominent cause of childhood strokes. 10 families with familial chilblain lupus related to TREX1 mutations were reported previously in the literature, in which homozygote D18N variant in TREX1 gene was related to chilblains with cerebral vasculitis. In this report, whole-exome-sequencing revealed a homozygote R114C mutation in TREX1 gene was shown in two siblings with recurrent chilblains whom one of them was the second case accompanied by cerebral vasculitis in the literature. As a result, the approach of WES in clinical use revealed a novel mutation in clinically heterogenous patients to provide genetic counseling.

An update on multiple sclerosis in children: diagnosis, therapies, and prospects for the future

INTRODUCTION

Multiple sclerosis (MS), a chronic demyelinating disease of the central nervous system, is increasingly being recognized in children and adolescents. Pediatric MS follows a relapsing-remitting course at onset, with a risk for early cognitive impairment. Areas covered: In this review, we discuss the clinical features of acute demyelinating syndromes in children and risk factors that increase the likelihood of a diagnosis of MS. We also address the application of diagnostic criteria for MS in children, immunological features, therapeutic options and psychosocial considerations for children and adolescents with MS. Expert commentary: Collaborative multicenter clinical trials and research efforts are key to the advancement in understanding the pathophysiology and therapeutic strategies for multiple sclerosis across the lifespan.

Mycophenolate mofetil as induction and long-term maintaining treatment in childhood: Primary angiitis of the central nervous system

OBJECTIVE

To report our single centre experience in treating 4 children affected by childhood primary central nervous system vasculitis (cPACNS) using mycophenolate mofetil (MMF).

METHODS

From December 2011 to August 2015, 4 patients (3 males; age range: 9 months-13 years) affected by cPACNS were collected. Enrolled children received the following treatment protocol: acetylsalicylic acid and/or anticoagulant therapy with low molecular weight heparin (LMWH) 100 U/k BID replaced by acenocoumarol; methyl-prednisolone (30mg/kg/day for 3-5 days) followed by prednisone (2mg/kg/day), tapered and discontinued over 7-8 months; MMF used for induction therapy and subsequent maintenance phase (750-1000mg/m² BID, half-dose for the first 10-15 days followed by full-dose).

RESULTS

In all children, no relapse of cerebral vasculitis occurred during the whole follow-up period and all of them improved while in MMF treatment. Magnetic resonance imaging (MRI) and magnetic resonance angiography (MRA), performed at 6, 9 or 12 months intervals, showed no progression or even improvement of the typical radiological findings. Medium period of MMF treatment was 29 months (range: 10-42 months). No major drug-related adverse events were documented.

CONCLUSION

We report for the first time on the efficacy and safety of MMF in the induction and maintenance of clinical remission in cPACNS. Our single centre experience of MMF use in treating cPACNS seems represent an appealing, alternative and safe option in this clinical setting over a long-term follow-up.

[Childhood vasculitis]

BACKGROUND

The primary vasculitides are rare conditions in childhood. The most common disease subtypes are Schönlein-Henoch purpura and Kawasaki's syndrome, which frequently have a self-limiting course. In the majority of vasculitides, the etiology remains unknown. Environmental exposure, including infections, is suspected to trigger an autoinflammatory response in predisposed individuals.

GOAL

The aim of this review is to present the various aspects of childhood vasculitis.

MATERIALS AND METHODS

Reviews and special original papers on childhood vasculitis, published classification criteria and current therapy guidelines were reviewed and summarized.

RESULTS

The classification of vasculitides in childhood has been modified from the previous adult Chapel Hill classification for vasculitides in 2008. Most therapy recommendations for children are adapted from results of studies in adults. This review covers the current classifications, pathogenesis, clinical manifestations and therapy recommendations for children.

DISCUSSION

Although etiology and pathogenesis of many vasculitides in childhood are still unknown, clarifying diagnostic methods and effective therapeutic options are available. The knowledge about various forms of disease manifestation may contribute to an early diagnosis and timely initiation of treatment, which may prevent devastating irreversible impairment.

Adapting Knowledge Translation Strategies for Rare Rheumatic Diseases

Rare rheumatic diseases present unique challenges to knowledge translation (KT) researchers. There is often an urgent need to transfer knowledge from research findings into clinical practice to facilitate earlier diagnosis and better outcomes. However, existing KT frameworks have not addressed the specific considerations surrounding rare diseases for which gold standard evidence is not available. Several widely adopted models provide guidance for processes and problems associated with KT. However, they do not address issues surrounding creation or synthesis of knowledge for rare diseases. Additional problems relate to lack of awareness or experience in intended knowledge users, low motivation, and potential barriers to changing practice or policy. Strategies to address the challenges of KT for rare rheumatic diseases include considering different levels of evidence available, linking knowledge creation and transfer directly, incorporating patient and physician advocacy efforts to generate awareness of conditions, and selecting strategies to address barriers to practice or policy change.

Central nervous system vasculitis in adults and children

Primary angiitis of the central nervous system (PACNS) is an inflammatory brain disease targeting the cerebral blood vessels, leading to a wide spectrum of signs and symptoms, including neurologic deficits, cognitive dysfunction, and psychiatric symptoms. The inflammation could be reversible if diagnosed and treated early. The diagnosis requires the careful consideration and rapid evaluation of systemic underlying conditions and disease mimics. The differential diagnosis is distinctly different for angiography-positive and -negative PACNS subtypes and differs depending on age, so there is childhood PACNS or adult PACNS. Distinct disease subtypes have been described, with characteristic disease course, neuroimaging findings, and histopathologic features. Novel and traditional biomarkers, including von Willebrand factor antigen and cytokine levels, can help diagnose, and define subtype and disease activity. Treatment of PACNS should be tailored to the disease subtypes and clinical symptoms. Beyond immunosuppression it should include medications to control symptoms in order to support and enhance the child's or adult's ability to actively participate in rehabilitation. The mortality of PACNS has decreased; studies determining the morbidity and its determinants are urgently needed.

Primary angiitis of the central nervous system: A rare and reversible cause of childhood stroke

Childhood primary angiitis of the central nervous system (cPACNS) is a rare and a potentially fatal cause of childhood stroke. The disease poses a diagnostic dilemma for the clinicians due to overlapping and varied clinical manifestations such as headache, focal acute neurological deficits, cognitive impairment, or encephalopathy. We report a young boy who presented with low-grade fever and headache but rapidly progressed to develop acute encephalopathy and quadriparesis with multiple cranial nerve palsies, masquerading as acute disseminated encephalomyelitis. The neuroimaging was suggestive of vasculitis. He was diagnosed as cPACNS and recovered with immunosuppressive therapy.

Cerebrovascular disease

With 16.9 million people who suffered a first-ever stroke in 2010 worldwide, stroke is a very common vascular disease. Epidemiologic studies have played an essential role in assessing this burden and in detecting the risk factors for stroke. Primary prevention of these risk factors, primarily hypertension, smoking, diabetes, and atrial fibrillation, has reduced the incidence in high-income countries. However, stroke remains a major cause of death and disability, and therefore research should be continued. Subarachnoid hemorrhages are less prevalent than strokes but have an even higher risk of death. Similar to stroke, epidemiologic studies identified smoking and hypertension as its most important risk factors, together with excessive alcohol intake. Although rare, arterial dissections, CADASIL, arteriovenous malformations, venous sinus thrombosis, moyamoya disease, and vasculitis can lead to serious symptoms. The burden and risk factors of those rare diseases are more challenging to assess. Whenever possible, they should be recognized in a timely manner for their increased risk of stroke, but most often they are diagnosed only at the time of stroke. Some cerebrovascular abnormalities do not result in immediate symptoms. This subclinical cerebrovascular disease includes silent infarcts, white-matter lesions, and microbleeds, and is incidentally found by neuroimaging. These lesions are not innocent, as several epidemiologic studies have associated subclinical cerebrovascular disease with an increased risk of stroke, cognitive decline, dementia, and death.

Primary angiitis of the central nervous system in adults and children

Primary angiitis of the central nervous system (PACNS) is a rare disease, although it is increasingly recognized both in adults and children. Little is known about pathogenesis, but efforts at classification into subtypes are being made, and the distinction of PACNS from reversible cerebral vasoconstriction syndrome has been a major advance. The prognosis for improvement, or at least stabilization, of neurologic function is good with prompt and aggressive treatment, but the diagnosis continues to be challenging. Refinement of treatment strategies is needed. Multicenter collaboration may be crucial to make additional progress via randomized trials.

Biopsy-proven case of childhood primary angiitis of the central nervous system presenting with bilateral panuveitis and anisocoria

Childhood primary angiitis of the central nervous system (cPACNS) is a rare and poorly understood immune-mediated vasculitis that preferentially affects blood vessels of the central nervous system (CNS). It must be distinguished from other disorders to initiate prompt treatment and improve the patient's prognosis. The presentation of cPACNS is highly variable, making a clinical diagnosis challenging. However, MRI may be helpful in showing typical findings including perivascular space inflammation and enhancement. Identification of these imaging features allows the radiologist to specifically suggest this rare diagnosis. The purpose of this manuscript is to present a biopsy-confirmed case of cPACNS in a 9-year-old girl who presented uniquely with panuveitis and anisocoria, and emphasize the MRI features that should prompt the radiologist to suggest this rare diagnosis.

Evaluation and treatment of autoimmune neurologic disorders in the pediatric intensive care unit

Autoimmunity is being increasingly recognized as a cause of neurologic presentations both inside and outside the intensive care unit (ICU) setting. Pediatric autoimmune neurologic diseases likely to be seen in the ICU include autoimmune encephalitidies such as N-Methyl-D-aspartate (NMDA) receptor encephalitis, central nervous system vasculitis, demyelinating disorders, and neurologic involvement of systemic autoimmune disorders. In addition, there are conditions of suspected autoimmune etiology such as febrile infection-related epilepsy syndrome (FIRES) and rapid-onset obesity, hypoventilation, hypothalamic dysfunction, and autonomic dysregulation (ROHHAD) syndrome that are rare, but when they do present, it is often to the ICU. Refractory seizures, altered mental status, and disordered breathing are the most common indications for intensive care for these patients.

Distinct phenotype clusters in childhood inflammatory brain diseases: implications for diagnostic evaluation

OBJECTIVE

To identify distinct clusters of children with inflammatory brain diseases based on clinical, laboratory, and imaging features at presentation, to assess which features contribute strongly to the development of clusters, and to compare additional features between the identified clusters.

METHODS

A single-center cohort study was performed with children who had been diagnosed as having an inflammatory brain disease between June 1, 1989 and December 31, 2010. Demographic, clinical, laboratory, neuroimaging, and histologic data at diagnosis were collected. K-means cluster analysis was performed to identify clusters of patients based on their presenting features. Associations between the clusters and patient variables, such as diagnoses, were determined.

RESULTS

A total of 147 children (50% female; median age 8.8 years) were identified: 105 with primary central nervous system (CNS) vasculitis, 11 with secondary CNS vasculitis, 8 with neuronal antibody syndromes, 6 with postinfectious syndromes, and 17 with other inflammatory brain diseases. Three distinct clusters were identified. Paresis and speech deficits were the most common presenting features in cluster 1. Children in cluster 2 were likely to present with behavior changes, cognitive dysfunction, and seizures, while those in cluster 3 experienced ataxia, vision abnormalities, and seizures. Lesions seen on T2/fluid-attenuated inversion recovery sequences of magnetic resonance imaging were common in all clusters, but unilateral ischemic lesions were more prominent in cluster 1. The clusters were associated with specific diagnoses and diagnostic test results.

CONCLUSION

Children with inflammatory brain diseases presented with distinct phenotypical patterns that are associated with specific diagnoses. This information may inform the development of a diagnostic classification of childhood inflammatory brain diseases and suggest that specific pathways of diagnostic evaluation are warranted.

Childhood inflammatory brain diseases: pathogenesis, diagnosis and therapy

Inflammatory brain diseases (IBrainDs) are a leading cause of devastating neurological deficits or neuropsychiatric syndromes in previously healthy children. The spectrum is expanding rapidly and new disease entities have been discovered in the last decade. IBrainD can occur as a primary disease or may occur secondary to an underlying cause. This review focuses on the clinical presentation, diagnostic features, pathology and histology characteristics and treatment of the primary childhood IBrainDs.

Childhood central nervous system vasculitis

Inflammatory brain diseases in childhood are underrecognized and lead to devastating yet potentially reversible deficits. New-onset neurologic or psychiatric deficits in previously healthy children mandate an evaluation for an underlying inflammatory brain disease. Distinct disease entities, such as central nervous system (CNS) vasculitis, are now being increasingly reported in children. Clinical symptoms, initial laboratory test, and neuroimaging studies help to differentiate between different causes; however, more invasive tests, such as lumbar puncture, conventional angiography, and/or brain biopsy, are usually necessary before the start of treatment. This article focuses on childhood CNS vasculitis.

Primary and secondary central nervous system vasculitis

Central nervous system vasculitis is an increasingly recognized inflammatory brain disease causing devastating neurological deficits and psychiatric manifestations in previously healthy children. Primary central nervous system vasculitis represents an isolated inflammatory attack targeting the cerebral vessels. In contrast, in children with secondary central nervous system vasculitis, an underlying condition can be identified. The spectrum of childhood primary and secondary central nervous system vasculitis is rapidly expanding, as is the differential diagnosis including nonvasculitic inflammatory brain diseases and noninflammatory vasculopathies. Early recognition, rapid diagnostic evaluation, and initiation of treatment have led to improved morbidity and mortality. This review focuses on clinical, laboratory, and neuroimaging characteristics of the distinct subtypes of primary childhood central nervous system vasculitis, reports the etiology of secondary central nervous system vasculitis, provides an overview of the differential diagnosis, and reviews the current approaches in treatment.

Cerebral haemorrhage in the presence of primary childhood central nervous system vasculitis--a review

PURPOSE

The aim of the study was to evaluate frequency and clinical relevance of haemorrhagic events associated with primary angiitis of the central nervous system in childhood (cPACNS), a rare but increasingly recognized disease with varying clinical presentations.

METHOD

A systematic literature review from 1990 onwards was conducted to identify reported cases of cPACNS.

RESULTS

A total of 110 paediatric patients met the inclusion criteria. The median age was 9.5 years. Seven children (7/110, 6.4 %) demonstrated cerebral haemorrhage. Death occurred only in children with cerebral haemorrhage (4/110, 3.6 %); both a sudden and prolonged course of disease was observed.

CONCLUSION

PACNS is a rare disease and the occurrence of haemorrhage with this condition is even rarer; however, the risk of an unfavourable outcome under these circumstances seems to be increased. PACNS adds to the list of differential diagnoses of intracerebral haemorrhage in the paediatric population.

Childhood primary angiitis of the central nervous system: identifying disease trajectories and early risk factors for persistently higher disease activity

OBJECTIVE

To compare clinical, laboratory, and imaging characteristics of childhood primary angiitis of the central nervous system (PACNS) subtypes at diagnosis and during followup; to characterize disease activity trajectories in childhood PACNS subtypes; and to identify early risk factors for higher disease activity.

METHODS

We performed a single-center cohort study of consecutive children diagnosed as having childhood PACNS. Demographic, clinical, laboratory, and imaging data were collected at diagnosis and during standardized clinic visits. Outcome measures included disease activity measured by physician's global assessment. Descriptive statistics were used to assess characteristics of the study cohort, and longitudinal data were analyzed using linear mixed-effects regression.

RESULTS

The study cohort consisted of 45 patients with childhood PACNS; 26 had angiography-negative childhood PACNS and 19 had angiography-positive childhood PACNS. There were 24 females, the median age at diagnosis was 9.8 years, and the median followup period was 1.8 years. Patients with angiography-negative childhood PACNS were more likely to be female and to present with seizures, cognitive dysfunction, vision abnormalities, high levels of inflammatory markers, and bilateral findings on magnetic resonance imaging (MRI). Motor deficits and ischemic MRI lesions were more common in angiography-positive disease. Disease activity decreased significantly after treatment in all patients. Distinct trajectories of disease activity over time were identified for both childhood PACNS subtypes. Patients with angiography-negative childhood PACNS had persistently higher disease activity. Seizures at presentation also predicted higher disease activity over time.

CONCLUSION

Distinct subtypes of childhood PACNS have unique disease activity trajectories. Patients with angiography-negative disease and seizures at presentation experience higher disease activity. Early recognition of this high-risk cohort may enable the treating physician to initiate targeted therapies and prevent long-term brain injury.

Primary central nervous system vasculitis: pathology and mechanisms

Primary vasculitis of the central nervous system (PCNSV) is a rare and diagnostically challenging form of vasculitis limited to the brain and/or spinal cord. It is a complex and often severe disease with multifaceted clinical and pathological appearances, suggesting multiple disease subtypes and the potential existence of multiple etiologic pathways. We describe in detail the clinical, imaging, and neuropathological findings of PCNSV summarizing literature data and our observations from a cohort of 131 patients diagnosed at Mayo Clinic over a 25-year period (1983-2007). Unlike systemic vasculitis, little is known regarding PCNSV pathogenesis and the involved immunological mechanisms. Increased recognition of the disease spectrum and in-depth characterization of its histopathologic and immunological phenotype will be critical to eventually understanding the underlying derangements and mechanisms driving PCNSV. Improved understanding of the pathogenetic mechanisms of the disease may also help determine whether the different histologic patterns and clinical subsets represent more than one disease and ultimately may permit development of novel diagnostic and therapeutic strategies for it.

Pediatric vasculitis

Childhood vasculitis is a challenging and complex group of conditions that are multisystem in nature and often require integrated care from multiple subspecialties, including rheumatology, dermatology, cardiology, nephrology, neurology, and gastroenterology. Vasculitis is defined as the presence of inflammation in the blood vessel wall. The site of vessel involvement, size of the affected vessels, extent of vascular injury, and underlying pathology determine the disease phenotype and severity. This article explores the classification and general features of pediatric vasculitis, as well as the clinical presentation, diagnostic evaluation, and therapeutic options for the most common vasculitides.

Towards a consensus-based classification of childhood arterial ischemic stroke

BACKGROUND AND PURPOSE

The implementation of uniform nomenclature and classification in adult arterial ischemic stroke (AIS) has been critical for defining outcomes and recurrence risks according to etiology and in developing risk-stratified treatments. In contrast, current classification and nomenclature in childhood AIS are often overlapping or contradictory. Our purpose was to develop a comprehensive consensus-based classification system for childhood AIS.

METHODS

Using a modified-Delphi method, members of the International Pediatric Stroke Study (IPSS) developed the Childhood AIS Standardized Classification And Diagnostic Evaluation (CASCADE) criteria. Two groups of pediatric stroke specialists from the IPSS classified 7 test cases using 2 methods each: (1) classification typical of the individual clinician's current clinical practice; and (2) classification based on the CASCADE criteria. Group 1 underwent in-person training in the utilization of the CASCADE criteria. Group 2 classified the same cases via an online survey, including definitions but without training. Inter-rater reliability (IRR) was assessed via multi-rater unweighted κ-statistic.

RESULTS

In Group 1 (with training), IRR was improved using CASCADE criteria (κ=0.78, 95% CI=[0.49, 0.94]), compared with typical clinical practice (κ=0.40, 95% CI=[0.11, 0.60]). In Group 2 (without training), IRR was lower than among trained raters (κ=0.61, 95% CI=[0.29, 0.77]), but higher than current practice (κ=0.23, 95% CI=[0.03, 0.36]).

CONCLUSIONS

A new, consensus-based classification system for childhood AIS, the CASCADE criteria, can be used to classify cases with good IRR. These preliminary findings suggest that the CASCADE criteria may be particularity useful in the setting of prospective multicenter studies in childhood-onset AIS, where standardized training of investigators is feasible.

Noninfectious central nervous system inflammatory disorders

Acute central nervous system (CNS) inflammation may occur as a monophasic illness or may represent the first attack of a chronic inflammatory disorder, such as multiple sclerosis, neuromyelitis optica, or CNS vasculitis. We review essential components of the initial assessment, diagnostic workup, acute and chronic management strategies, and research issues pertaining to children with CNS inflammatory diseases and suggest methods for these competencies to be attained during the course of child neurology residency training.