Diagnostic yield of brain biopsies in children presenting to neurology

Decompressive craniectomy in the acute fulminant cerebral edema

Acute fulminant cerebral edema is a type of rapidly progressive encephalitis that occurs in children and is associated with significant morbidity and mortality. We present a clinical case with seizures, rapid neurological deterioration and the early appearance of cerebral herniation signs. Although the radiological tests were initially normal and there are no established parameters that predict the evolution of encephalitis to a rapidly progressive subtype, the clinical evolution forced to consider the decompressive craniectomy due to the lack of response to the medical management of the cerebral edema. It may be necessary take a brain biopsy to confirm the etiology of the encephalitis origin of acute fulminant cerebral edema. The objective of surgery should be not only to increase survival, but also to reduce subsequent neurological sequelae.

Diagnostic yield of postmortem brain examination following premortem brain biopsy for neoplastic and nonneoplastic disease

Medical autopsies have decreased in frequency due in part to advances in radiological techniques and increased availability of molecular and other ancillary testing. However, premortem diagnosis of CNS disease remains challenging; while ∼90% of brain tumor biopsies are diagnostic, only 20%-70% of biopsies for presumed nonneoplastic disease result in a specific diagnosis. The added benefits of performing an autopsy following surgical brain biopsy are not well defined. A retrospective analysis was performed of patients who underwent brain biopsy and autopsy at Brigham and Women's Hospital from 2003 to 2022. A total of 135 cases were identified, including 95 (70%) patients with primary CNS neoplasms, 16 (12%) with metastatic tumors, and 24 (18%) with nonneoplastic neurological disease. Diagnostic concordance between biopsy and autopsy diagnosis was excellent both for primary CNS neoplasms (98%) and metastatic tumors (94%). Conversely, patients with nonneoplastic disease received definitive premortem diagnoses in 7/24 (29%) cases. Five (21%) additional patients received conclusive diagnoses following autopsy; 8 (33%) received a more specific differential diagnosis compared to the biopsy. Overall, autopsy confirmed premortem diagnoses or provided new diagnostic information in 131/135 (97%) cases, highlighting the value in performing postmortem brain examination in patients with both neoplastic and nonneoplastic diseases.

Double-stranded RNA immunohistochemistry as a screening tool for viral encephalitis

OBJECTIVES

Viral infections of the central nervous system can be challenging to diagnose because of the wide range of causative agents and nonspecific histologic features. We sought to determine whether detection of double-stranded RNA (dsRNA), produced during active RNA and DNA viral infections, could be used to select cases for metagenomic next-generation sequencing (mNGS) from formalin-fixed, paraffin-embedded brain tissue.

METHODS

Eight commercially available anti-dsRNA antibodies were optimized for immunohistochemistry (IHC) and the top antibody tested in a series of cases with confirmed viral infections (n = 34) and cases with inflammatory brain lesions of unclear etiology (n = 62).

RESULTS

Among known positives, anti-dsRNA IHC produced a strong cytoplasmic or nuclear staining pattern for Powassan virus, West Nile virus, rabies virus, JC polyoma virus, and adenovirus while failing to detect Eastern equine encephalitis virus, Jamestown Canyon virus, or any herpesvirus. All the unknown cases were negative by anti-dsRNA IHC, while mNGS detected rare viral reads (0.3-1.3 reads per million total reads) in 2 cases (3%), with only 1 having potential clinical significance.

CONCLUSIONS

Anti-dsRNA IHC can effectively identify a subset of clinically relevant viral infections but not all. The absence of staining should not exclude cases from mNGS if sufficient clinical and histologic suspicion exists.

Childhood Cerebral Vasculitis : A Multidisciplinary Approach

Cerebral vasculitis is increasingly recognized as a common cause of pediatric arterial stroke. It can present with focal neurological deficits, psychiatric manifestations, seizures, and encephalopathy. The etiopathogenesis of childhood cerebral vasculitis (CCV) is multifactorial, making an inclusive classification challenging. In this review, we describe the common and uncommon CCV with a comprehensive discussion of etiopathogenesis, the role of various imaging modalities, and advanced techniques in diagnosing CCV. We also highlight the implications of relevant clinical, laboratory, and genetic findings to reach the final diagnosis. Based on the clinicoradiological findings, a stepwise diagnostic approach is proposed to facilitate CCV diagnosis and rule out potential mimics. Identification of key clinical manifestations, pertinent blood and cerebrospinal fluid results, and evaluation of central nervous system vessels for common and disease-specific findings will be emphasized. We discuss the role of magnetic resonance imaging, MR angiography, and vessel wall imaging as the imaging investigation of choice, and reservation of catheter angiography as a problem-solving tool. We emphasize the utility of brain and leptomeningeal biopsy for diagnosis and exclusion of imitators and masqueraders.

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.

Elevated intracranial pressure requiring decompressive craniectomy in a child with progressive primary angiitis of the central nervous system: a case report

BACKGROUND

Elevated intracranial pressure is a potentially catastrophic complication of neurologic injury in children. Successful management of elevated intracranial pressure requires prompt recognition and therapy directed at both reducing intracranial pressure and reversing its underlying cause. A rare condition that causes elevated intracranial pressure is childhood primary angiitis of the central nervous system, which is a rare inflammatory central nervous system disease that poses diagnostic and therapeutic challenges. To our knowledge, this is the first reported case of angiography-positive progressive childhood primary angiitis of the central nervous system requiring decompressive hemicraniectomy for refractory elevated intracranial pressure in children.

CASE PRESENTATION

We report the case of a 5-year-old Saudi girl who presented to the pediatric emergency department with fever and new-onset status epilepticus. She had elevated inflammatory markers with radiological and histopathological evidence of angiography-positive progressive childhood primary angiitis of the central nervous system, complicated by elevated intracranial pressure. Despite medical management for both childhood primary angiitis of the central nervous system and elevated intracranial pressure, her neurological status continued to deteriorate and the elevated intracranial pressure became refractory. She developed right uncal, right subfalcine, and tonsillar herniation requiring decompressive hemicraniectomy with a favorable neurological outcome.

CONCLUSION

Decompressive craniectomy might be considered in cases of angiography-positive progressive childhood primary angiitis of the central nervous system with elevated intracranial pressure refractory to medication. A multidisciplinary approach for the decision of decompressive craniectomy is advised to ensure patient safety and avoid possible morbidities and mortality.

The utility of brain biopsy in pediatric cryptogenic neurological disease

OBJECTIVE

The authors' aim was to characterize a single-center experience of brain biopsy in pediatric cryptogenic neurological disease.

METHODS

The authors performed a retrospective review of consecutive brain biopsies at a tertiary pediatric neurosciences unit between 1997 and 2017. Children < 18 years undergoing biopsy for neurological pathology were included. Those with presumed neoplasms and biopsy performed in the context of epilepsy surgery were excluded.

RESULTS

Forty-nine biopsies in 47 patients (25 females, mean age ± SD 9.0 ± 5.3 years) were performed during the study period. The most common presenting symptoms were focal neurological deficit (28.6%) and focal seizure (26.5%). Histopathological, microbiological, and genetic analyses of biopsy material were contributory to the diagnosis in 34 cases (69.4%). Children presenting with focal seizures or with diffuse (> 3 lesions) brain involvement on MRI were more likely to yield a diagnosis at biopsy (OR 3.07 and 2.4, respectively). Twelve patients were immunocompromised and were more likely to yield a diagnosis at biopsy (OR 6.7). Surgery was accompanied by severe complications in 1 patient. The most common final diagnoses were infective (16/49, 32.7%), followed by chronic inflammatory processes (10/49, 20.4%) and occult neoplastic disease (9/49, 18.4%). In 38 cases (77.6%), biopsy was considered to have altered clinical management.

CONCLUSIONS

Brain biopsy for cryptogenic neurological disease in children was contributory to the diagnosis in 69.4% of cases and changed clinical management in 77.6%. Biopsy most commonly revealed underlying infective processes, chronic inflammatory changes, or occult neoplastic disease. Although generally safe, the risk of severe complications may be higher in immunocompromised and myelosuppressed children.

Clinical approach to the diagnosis of autoimmune encephalitis in the pediatric patient

Objective

Autoimmune encephalitis (AE) is an important and treatable cause of acute encephalitis. Diagnosis of AE in a developing child is challenging because of overlap in clinical presentations with other diseases and complexity of normal behavior changes. Existing diagnostic criteria for adult AE require modification to be applied to children, who differ from adults in their clinical presentations, paraclinical findings, autoantibody profiles, treatment response, and long-term outcomes.

Methods

A subcommittee of the Autoimmune Encephalitis International Working Group collaborated through conference calls and email correspondence to consider the pediatric-specific approach to AE. The subcommittee reviewed the literature of relevant AE studies and sought additional input from other expert clinicians and researchers.

Results

Existing consensus criteria for adult AE were refined for use in children. Provisional pediatric AE classification criteria and an algorithm to facilitate early diagnosis are proposed. There is also discussion about how to distinguish pediatric AE from conditions within the differential diagnosis.

Conclusions

Diagnosing AE is based on the combination of a clinical history consistent with pediatric AE and supportive diagnostic testing, which includes but is not dependent on antibody testing. The proposed criteria and algorithm require validation in prospective pediatric cohorts.

Childhood Small Vessel Primary Angiitis of the Central Nervous System: A Treatable Cause of Super-refractory Status Epilepticus

Childhood primary angiitis of the central nervous system (cPACNS) is a rare inflammatory disease of brain vessels. The small vessel subtype is diagnosed on brain biopsy and often presents with cognitive and behavioral changes, headaches, and seizures. However, there are few reported cases of super-refractory status epilepticus in children. We present a case of small vessel cPACNS complicated by super-refractory status epilepticus requiring burst suppression for 4 weeks in addition to multiple antiseizure medications and the ketogenic diet. Our patient was also treated with intravenous and oral steroids, intravenous immunoglobulin, and cyclophosphamide before starting maintenance therapy with mycophenolate mofetil. After prolonged rehabilitation, he recovered almost completely and has a normal neurologic examination with rare epileptiform activity on electroencephalogram (EEG). This is one of the longest cases of status epilepticus in small vessel cPACNS in the literature. We illustrate that super-refractory status epilepticus can be the first manifestation of small vessel cPACNS in previously healthy children and that symptomatic management of seizures with concurrent immunosuppression to treat the underlying pathology resulted in favorable neurologic outcomes.

Clinical Perspective on Primary Angiitis of the Central Nervous System in Childhood (cPACNS)

Non-arteriosclerotic arteriopathies have emerged as important underlying pathomechanism in pediatric arterial ischemic stroke (AIS). The pathogenesis and classification of cerebral arteriopathies in childhood are heterogeneous. Different classifications base on (i) the anatomic site; (ii) the distribution and size of the affected vessel; (iii) the time course, for example, transient vs. progressive, monophasic vs. recurrent; (iv) the putative pathogenesis; (v) the magnetic resonance imaging morphology of the vasculopathies. Inflammation affecting the cerebral vessels is increasingly recognized as common cause of pediatric AIS. Primary cerebral vasculitis or primary angiitis of the central nervous system (CNS) in childhood (cPACNS) is an important differential diagnosis in pediatric AIS. Primary angiitis of the CNS is a rare disorder, and the pathogenesis is poorly understood so far. The current classification of cPACNS is based on the affected cerebral vessel size, the disease course, and angiographic pattern. Two large subtypes are currently recognized comprising large- and medium-sized vessel CNS vasculitis referred to as angiography-positive cPACNS and angiography-negative small vessel cPACNS. As the clinical manifestations of cPACNS are rather diverse, precise diagnosis can be challenging for the treating pediatrician because of the lack of vital laboratory tests or imaging features. Initial misdiagnosis is common because of overlapping phenotypes and pediatric AIS mimics. As untreated cPACNS is associated with a high morbidity and mortality, timely diagnosis, and induction of immunomodulatory and symptomatic therapy are essential. Survival and neurological outcome depend on early diagnosis and prompt therapy. Primary angiitis of the central nervous system in childhood differs in several aspects from primary cerebral angiitis in adults. The aim of this article is to give a brief comprehensive summary on pediatric primary cerebral vasculitis focusing on the clinical perspective regarding the classification, the putative pathogenesis, the disease course, the diagnostic tools, and emerging treatment options. A modified terminology for clinical practice is discussed.

Evaluation and Acute Management of Ischemic Stroke in Infants and Children

PURPOSE OF REVIEW

This article provides an overview of stroke in neonates, infants, and children.

RECENT FINDINGS

Arterial ischemic stroke and cerebral venous sinus thrombosis are increasingly recognized in childhood as important causes of lifelong morbidity and mortality. Diagnosis of arterial ischemic stroke is frequently delayed, as acute neurologic deficits can be challenging to detect in the young child, and stroke is often not considered in the differential diagnosis. Neurologic sequelae following stroke are common, and strategies to minimize stroke size and optimize recovery are being developed. Recurrent arterial ischemic stroke is not uncommon, particularly in children with cerebral arteriopathy. Cerebral venous sinus thrombosis causes obstruction of venous outflow leading to venous infarcts. Complications include hemorrhagic conversion of infarcts and increased intracranial pressure. Without treatment, thrombus extension with increased symptoms is common. Robust guidelines of care that exist for adults do not exist for children, particularly for children with arterial ischemic stroke.

SUMMARY

The approach to stroke in infants and children can be informed by clinical experience in pediatric stroke and cerebral venous sinus thrombosis, the extensive literature on pediatric thrombosis, and extrapolation from data from adult patients.

Diagnosis and Treatment of Primary Central Nervous System Angiitis

PURPOSE OF REVIEW

Primary central nervous system angiitis (PCNSA) is a rare disease. Varying clinical pictures coupled with lack of sensitive and specific diagnostic tests lead to challenges in management of these patients. This unfortunately may lead to both under- or over-diagnosis and unnecessary treatment. It is important to recognize the different conditions that may mimic the clinical and radiologic presentation. We present a contemporary literature review that should update physicians who encounter this patient population.

RECENT FINDINGS

Recent additions to the literature in form of case reports and single-center series show that digital subtraction angiography was the most widely used test to diagnose PCNSA. It is also important to note that brain biopsy is still considered "gold standard" and should be pursued as it not only has information that establishes the diagnosis but also may help in ruling out the diagnosis from mimics. In around 39% of suspected cases, an alternate diagnosis was eventually confirmed highlighting the importance of a comprehensive work-up. For treatment, almost all the literature supports the use of glucocorticoids as the initial treatment and if the patient has a relapse or develops steroid toxicity then the second most commonly used agent was cyclophosphamide. There are increasing reports of benefits with other agents such as methotrexate, azathioprine, mycophenolate, infliximab, and etanercept. The diagnosis and management of PCNSA continues to be a challenge. Formation of prospective patient registries with continued immunologic research for novel targets and immunomodulatory modalities may hold promise for future care of these patients.

MRI and clinicopathological correlation of childhood primary central nervous system angiitis

AIM

To review the long-term clinical and imaging follow-up of eight children with histopathologically proven childhood primary central nervous system angiitis (cPACNS).

MATERIALS AND METHODS

Eight children (5-17 years, five female and three male patients) with biopsy-proven cPACNS vasculitis were reviewed retrospectively. All children were followed at the Children's Hospital of Eastern Ontario. Magnetic resonance imaging (MRI) images of the brain parenchyma and vessel pattern of the arteries of the circle of Willis were reviewed at baseline and follow-up(s). All MRI images were correlated with clinical and histopathological findings.

RESULTS

Seven (87.5%) children demonstrated parenchymal abnormalities: five of the seven (71.4%) presented with non-haemorrhagic lesions, one (14.3%) presented with a parenchymal bleed, and one (14.3%) showed diffuse oedema. One child remained negative for brain parenchymal abnormality at baseline and follow-up. Of the seven children with a parenchymal abnormality, parenchymal enhancement was seen in two (28.5%) and leptomeningeal enhancement was seen in one child. Only two children had positive diffusion-weighted imaging (DWI) restriction at baseline. Five of the seven children (71.4%) showed no magnetic resonance angiography (MRA) abnormalities at baseline. In one, MRA detected complete absence of flow. Follow-up MRA (24-74 months) demonstrated that five of the seven (71.4%) children had progressive paucity of the peripheral vascularity. Two children (28.5%) with shorter-term follow-up (7 and 13 months) did not demonstrate MRA changes.

CONCLUSION

Long-term follow-up MRA demonstrated progressive paucity of peripheral vessels, which could be secondary to the inflammation affecting the peripheral vasculature causing reduction in vessel lumen size beyond the resolution of the maximum intensity projection (MIP) reconstruction.

Consensus guidelines for the investigation and management of encephalitis in adults and children in Australia and New Zealand

Encephalitis is a complex neurological syndrome caused by inflammation of the brain parenchyma. The management of encephalitis is challenging because: the differential diagnosis of encephalopathy is broad; there is often rapid disease progression; it often requires intensive supportive management; and there are many aetiologic agents for which there is no definitive treatment. Patients with possible meningoencephalitis are often encountered in the emergency care environment where clinicians must consider differential diagnoses, perform appropriate investigations and initiate empiric antimicrobials. For patients who require admission to hospital and in whom encephalitis is likely, a staged approach to investigation and management is preferred with the potential involvement of multiple medical specialties. Key considerations in the investigation and management of patients with encephalitis addressed in this guideline include: Which first-line investigations should be performed?; Which aetiologies should be considered possible based on clinical features, risk factors and radiological features?; What tests should be arranged in order to diagnose the common causes of encephalitis?; When to consider empiric antimicrobials and immune modulatory therapies?; and What is the role of brain biopsy?

Diagnostic Value and Safety of Brain Biopsy in Patients With Cryptogenic Neurological Disease: A Systematic Review and Meta-analysis of 831 Cases

BACKGROUND

The role of brain biopsy in patients with cryptogenic neurological disease is uncertain.

OBJECTIVE

To determine the risks and benefits of diagnostic brain biopsy for nonneoplastic indications in immunocompetent patients.

METHODS

Appropriate studies were identified by searching electronic databases.

RESULTS

We screened 3645 abstracts and included 20 studies with a total of 831 patients. Indications for biopsy were: (1a) severe neurological disease of unknown etiology in adults (n = 7) and (1b) in children (n = 2); (2) suspected primary angiitis of the central nervous system (PACNS) (n = 3); (3) chronic meningitis of unknown cause (n = 3); (4) atypical dementia (n = 4); and (5) nonneoplastic disease (n = 1). Diagnostic success rates calculated for subgroups were 51.3% (34.5-68.1) for 1a, 53.8% (42.9-64.5) for 1b, 74.7% (64.0-84.1) for 2, 30.3% (17.2-45.4) for 3, and 60.8% (41.2-78.8) for 4. Clinical impact rates were 30.5% (13.6-50.6) for 1a (n = 6), 67.1% (42.8-87.3) for 1b (n = 2), 8.3% (2.3-20.0) for 3 (n = 1), and 14.2% (6.5-24.3) for 4 (n = 2). Lymphoma (n = 32) and Creutzfeldt-Jakob disease (n = 30) were the most common diagnoses on the final histopathology reports of positive brain biopsies in 1a. In 1b, encephalitis (n = 7), PACNS (n = 6), and demyelination (n = 6) were the most common. The odds ratio for achieving a diagnostic biopsy when there was a radiological target was 3.70 (P = .014, 95% confidence interval, 1.31-10.42).

CONCLUSION

Brain biopsy in cryptogenic neurological disease was associated with the highest diagnostic yield in patients with suspected PACNS. The greatest clinical impact was seen in children with cryptogenic neurological disease. The presence of a radiological target was associated with a higher diagnostic yield.

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.

[Childhood cerebral vasculitis]

Central nervous system vasculitides are defined as the invasion of the vascular wall by blood-borne inflammatory cells. In childhood, they may be classified according to their trigger event (infectious vs. non-infectious), their temporal course (time-limited vs. chronic), and the size of the affected vessel. Diseases apparently confined to the central nervous system are also distinguished from secondary forms, associated with infection or rheumatic or systemic inflammatory disorders. Large-vessel vasculitis, the most frequent form, causes stroke and presents with acute focal deficits. MR, or more seldom contrast angiography is required for the positive diagnosis, while the child's medical history conveys the etiological diagnosis. The clinical manifestations of small-vessel vasculitis include headaches, seizures, focal deficits, cognitive decline, and behavior changes that can occur insidiously over a few weeks or a few months. The diagnosis is based on the associated clinical and biological symptoms in secondary forms and on cerebromeningeal biopsy in primary forms. Secondary forms of vasculitides are treated according to the etiology. The injury of large basal arteries is often observed after infection, especially varicella, and is also called transient focal cerebral arteriopathy (TCA) or post-varicella arteriopathy (PVA). This focal, monophasic, and time-limited entity is highly specific of childhood. There are no arguments in the current literature supporting the hypothesis that an aggressive immunomodulatory treatment would be more effective, in terms of recurrence rate or functional outcome, than aspirin alone. In contrast, the diffuse, prolonged, and aggressive course of the rare primary vasculitis of the central nervous system requires a prolonged immunosuppressive treatment. The management of associated symptoms, treatment-related adverse effects, and sequelae is based on a multidisciplinary approach.

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.

Diagnosing central nervous system vasculitis in children

PURPOSE OF REVIEW

To review the current literature of childhood central nervous system vasculitis, and to discuss a tailored approach to diagnosis and treatment based on recent evidence.

RECENT FINDINGS

Primary angiitis of the central nervous system in children (cPACNS) is an increasingly recognized inflammatory brain disease with potentially devastating neurological consequences. The diagnostic approach should be tailored to the clinical presentation of the child with suspected cPACNS and should address the expanding spectrum of inflammatory and noninflammatory brain diseases with overlapping clinical features. New evidence has confirmed that elective brain biopsies in children have a higher diagnostic yield than in adults and improve our ability to diagnose angiography-negative cPACNS. Finally, observational studies have shown that early diagnosis and aggressive treatment lead to improved neurological outcomes and lower mortality rates in patients with cPACNS.

SUMMARY

This review summarizes the recent data on diagnosis, classification, treatment, and outcomes in cPACNS. Our improved understanding of cPACNS facilitates a tailored diagnostic approach that results in earlier diagnosis and initiation of therapy for this potentially reversible condition.

Pediatric multiple sclerosis

BACKGROUND

Pediatric multiple sclerosis (MS), once considered a rare childhood illness, has been increasingly identified as an important childhood acquired neurologic disease requiring early recognition and intervention.

SUMMARY

We present a comprehensive review of the current terminology of acquired central nervous system demyelination in children, pertinent investigations, including magnetic resonance imaging and cerebrospinal fluid cerebrospinal fluid studies, and an approach to the differential diagnosis of pediatric onset MS. In addition, the recent studies exploring the epidemiology and pathobiology will be discussed. Finally, we present an algorithm for the treatment of episodes of demyelination along with chronic immunomodulatory therapeutic options in this patient population.

CONCLUSIONS

Although some similarities exist to adult onset MS, MS onset during childhood and adolescence presents unique diagnostic challenges and requires specialized multidisciplinary care for optimal management. National and international collaborative studies are underway to aid in the understanding of the early and ongoing pathogenesis of MS.

Evaluation of brain biopsy in the diagnosis of severe neurologic disease of unknown etiology

OBJECTIVE

To determine the value of non-stereotactic brain biopsies in patients with severe neurologic disease of unknown etiology and indeterminate brain imaging.

METHODS

We reviewed 42 consecutive patients who underwent non-stereotactic brain biopsy at a single institution for evaluation of severe neurologic disease of unknown etiology. All patients had indeterminate or normal imaging results. Seventy-nine percent had been symptomatic for less than a year. Exclusion criteria were immunocompromise or a preoperative diagnosis of intracranial neoplasm. Diagnostic yield and surgical complication rate were calculated. We performed exploratory univariate analysis aimed at identifying clinical features possibly predictive of diagnostic biopsies.

RESULTS

A histologic diagnosis was achieved in 12 of 42 biopsies (29%). Three patients experienced minor transient complications from the procedure (7%). There were no permanent deficits or deaths. Treatment was altered based on biopsy result in five patients (12%). A more precise prognosis was obtained in eight patients (19%). In total, 11 different patients (26%) benefited from biopsy. Exploratory univariate analysis showed a possible inverse relationship between age and the likelihood of a diagnostic biopsy (OR=0.929; 95% CI=0.864-0.998).

CONCLUSIONS

Our data suggest that the value of non-stereotactic brain biopsy is sufficiently high and the morbidity sufficiently low to justify its use in carefully selected patients with severe neurologic disease that remains undiagnosed despite thorough less invasive evaluation.