Cerebral vasculitis as a clinical manifestation of neurosarcoidosis: A scoping review

The occurrence of cerebral vasculitis in individuals with neurosarcoidosis (NS) is considered to be rare. Although the number of relevant publications has increased in recent years, evidence is mostly limited to case reports. To obtain a better understanding of this rare and severe manifestation of disease, we carried out a scoping review on cerebral vasculitis in patients diagnosed with NS. The results of the review indicate that the diagnosis of cerebral vasculitis in patients with NS is made especially in patients with systemic sarcoidosis. However, recurrent strokes in patients with NS remains the main indicator of cerebral vasculitis. A tissue biopsy is considered the gold standard to confirm the diagnosis despite occasional false-negative results. Glucocorticoids and steroid-sparing agents are the most successful current treatments. Favorable outcomes were observed with strategies targeting TNFα and B cells. The goal of this review is to summarize the current literature and treatment options for cerebral vasculitis in patients with NS.

Neurosarcoidosis and Neurologic Complications of Sarcoidosis Treatment

Sarcoidosis is an immune-mediated multisystem granulomatous disorder. Neurosarcoidosis (NS) accounts for 5% to 35% of cases. The diagnostic evaluation of NS can be a clinical challenge. Gadolinium-enhanced magnetic resonance imaging (MRI) is the gold standard to evaluate central nervous system NS. In almost all cases treatment is warranted. Although glucocorticoids remain the first-line therapy in patients with sarcoidosis, in NS timely initiation of second- or third-line treatment is strongly recommended. Of these, tumor necrosis factor-alpha inhibitors are the most promising. However, the treatment itself may be responsible for/associated with developing neurologic symptoms mimicking NS. Thus, it is important to consider the possibility of drug-induced neurologic symptoms in sarcoidosis.

Immune-Mediated Myelopathies

OBJECTIVE

Immune-mediated myelopathies are conditions in which the immune system attacks the spinal cord. This article describes the distinguishing characteristics of immune-mediated myelopathies and treatment strategies for patients affected by these disorders.

LATEST DEVELOPMENTS

New biomarkers, such as aquaporin 4 and myelin oligodendrocyte glycoprotein antibodies, in the blood and spinal fluid have led to the identification of antigen-specific immune-mediated myelopathies and approved therapies to prevent disease progression.

ESSENTIAL POINTS

The first step in the diagnosis of an immune-mediated myelopathy is confirming that the immune system is the cause of the attack by excluding non-immune-mediated causes. The second step is to narrow the differential diagnosis based on objective biomarkers such as serology and MRI patterns. The third step is to treat the specific immune-mediated myelopathy by using evidence-based medicine.

Immunopathology of herpes simplex virus-associated neuroinflammation: Unveiling the mysteries

The immunopathology of herpes simplex virus (HSV)-associated neuroinflammation is a captivating and intricate field of study within the scientific community. HSV, renowned for its latent infection capability, gives rise to a spectrum of neurological expressions, ranging from mild symptoms to severe encephalitis. The enigmatic interplay between the virus and the host's immune responses profoundly shapes the outcome of these infections. This review delves into the multifaceted immune reactions triggered by HSV within neural tissues, intricately encompassing the interplay between innate and adaptive immunity. Furthermore, this analysis delves into the delicate equilibrium between immune defence and the potential for immunopathology-induced neural damage. It meticulously dissects the roles of diverse immune cells, cytokines, and chemokines, unravelling the intricacies of neuroinflammation modulation and its subsequent effects. By exploring HSV's immune manipulation and exploitation mechanisms, this review endeavours to unveil the enigmas surrounding the immunopathology of HSV-associated neuroinflammation. This comprehensive understanding enhances our grasp of viral pathogenesis and holds promise for pioneering therapeutic strategies designed to mitigate the neurological ramifications of HSV infections.

Risk Indicators of Sarcoidosis Evolution-Unified Protocol (RISE-UP): protocol for a multi-centre, longitudinal, observational study to identify clinical features that are predictive of sarcoidosis progression

INTRODUCTION

Sarcoidosis is a pulmonary and systemic granulomatous disease with a wide range of potential outcomes, from spontaneous resolution to end-stage organ damage and death. Currently, clinicians have no easy-to-use risk stratification tools for important clinical outcomes in sarcoidosis, such as progressive lung disease. This study will address two clinical practice needs: (1) development of a risk calculator that provides an estimate of the likelihood of pulmonary progression in sarcoidosis patients during the follow-up period and (2) determine the optimal interval for serial clinical monitoring (eg, 6, 12, 18 months) using these risk prediction tools.

METHODS AND ANALYSIS

The Risk Indicators of Sarcoidosis Evolution-Unified Protocol study is a National Institutes of Health-sponsored, longitudinal observational study of adults with pulmonary sarcoidosis who will be enrolled at five US tertiary care centres. Participants will be evaluated at approximately 6-month intervals for up to 60 months with collection of lung function, blood samples and clinical data. The target sample size is 557 and the primary objective is to determine which clinical features measured during a routine clinic visit carry the most prognostic information for predicting clinical progression of pulmonary sarcoidosis over the follow-up period. The primary outcome measure will be quantified by a clinically meaningful change in forced vital capacity, forced expiratory volume in 1 s or diffusing capacity of the lung for carbon monoxide. The secondary objective is to determine if blood biomarkers measured during a routine clinic visit can improve the risk assessment modelling for progression of pulmonary sarcoidosis over the follow-up period.

ETHICS AND DISSEMINATION

The study protocol has been approved by the Institutional Review Boards at each centre and the reliance Institutional Review Board overseeing the study (WCG, Protocol #20222400). Participants will provide informed consent prior to enrolment. Results will be disseminated via publication in a relevant peer-reviewed journal.

TRIAL REGISTRATION NUMBER

NCT05567133.

Vascular Involvement in Neurosarcoidosis: Early Experiences From Intracranial Vessel Wall Imaging

BACKGROUND AND OBJECTIVES

Cerebrovascular manifestations in neurosarcoidosis (NS) were previously considered rare but are being increasingly recognized. We report our preliminary experience in patients with NS who underwent high-resolution vessel wall imaging (VWI).

METHODS

A total of 13 consecutive patients with NS underwent VWI. Images were analyzed by 2 neuroradiologists in consensus. The assessment included segment-wise evaluation of larger- and medium-sized vessels (internal carotid artery, M1-M3 middle cerebral artery; A1-A3 anterior cerebral artery; V4 segments of vertebral arteries; basilar artery; and P1-P3 posterior cerebral artery), lenticulostriate perforator vessels, and medullary and deep cerebral veins. Cortical veins were not assessed due to flow-related artifacts. Brain biopsy findings were available in 6 cases and were also reviewed.

RESULTS

Mean patient age was 54.9 years (33-71 years) with an M:F of 8:5. Mean duration between initial diagnosis and VWI study was 18 months. Overall, 9/13 (69%) patients had vascular abnormalities. Circumferential large vessel enhancement was seen in 3/13 (23%) patients, whereas perforator vessel involvement was seen in 6/13 (46%) patients. Medullary and deep vein involvement was also seen in 6/13 patients. In addition, 7/13 (54%) patients had microhemorrhages in susceptibility-weighted imaging, and 4/13 (31%) had chronic infarcts. On biopsy, 5/6 cases showed perivascular granulomas with vessel wall involvement in all 5 cases.

DISCUSSION

Our preliminary findings suggest that involvement of intracranial vascular structures may be a common finding in patients with NS and should be routinely looked for. These findings appear concordant with previously reported autopsy literature and need to be validated on a larger scale.

Nerve biopsy: Current indications and decision tools

After initial investigation of patients presenting with symptoms suggestive of neuropathy, a clinical decision is made for a minority of patients to undergo further assessment with nerve biopsy. Many nerve biopsies do not demonstrate a definitive pathological diagnosis and there is considerable cost and morbidity associated with the procedure. This highlights the need for appropriate selection of patients, nerves and neuropathology techniques. Additionally, concomitant muscle and skin biopsies may improve the diagnostic yield in some cases. Several advances have been made in diagnostics in recent years, particularly in genomics. The indications for nerve biopsy have consequently changed over time. This review explores the current indications for nerve biopsies and some of the issues surrounding its use. Also included are comments on alternative diagnostic modalities that may help to supplant or reduce the use of nerve biopsy as a diagnostic test. These primarily include extraneural biopsy and neuroimaging techniques such as magnetic resonance neurography and nerve ultrasound. Finally, we propose an algorithm to assist in deciding when to perform nerve biopsies.

Neuroimaging findings in rheumatologic disorders

Patients with rheumatological diseases may present with neurological manifestations of peripheral and/or central nervous system (CNS). Symptoms may be related to underlying rheumatological disease or CNS effects of immune-modulating drugs. Early diagnosis and therapy may help prevent serious complications. Magnetic resonance imaging (MRI), given its excellent soft tissue details, is the preferred imaging modality when evaluating patients with rheumatological disease and suspected CNS involvement. We present a review of the neuroimaging manifestations of various rheumatic diseases with emphasis on the imaging findings on MRI.

Cerebrospinal fluid CD4+ /CD8+ ratio in diagnosing neurosarcoidosis

OBJECTIVE

Neurosarcoidosis affects 5%-10% of patients with sarcoidosis. CD4⁺ /CD8⁺ ratio in bronchoalveolar lavage is included in diagnostic routine for pulmonary sarcoidosis. Previously, it has been suggested that a cerebrospinal fluid CD4⁺ /CD8⁺ ratio ≥5 can be an aid in diagnosing neurosarcoidosis.

MATERIALS AND METHODS

This study included 66 cases where neurosarcoidosis was a differential diagnosis and hence subjected to the analysis of CSF CD4⁺ /CD8⁺ ratio by flow cytometry.

RESULTS

Eleven cases of neurosarcoidosis, had a significantly higher median CSF CD4⁺ /CD8⁺ ratio than the other group, P = .024. The median CSF CD4⁺ /CD8⁺ ratio was 4.2, hence not reaching the suggested level of ≥5 for diagnosing neurosarcoidosis. When combined, the elevated CSF CD4⁺ /CD8⁺ ratio ≥5 and an elevated CSF lymphocyte count (>3 lymphocytes/uL) gave a positive predictive value of 57% and a high negative predictive value of 88%, with a specificity of 95% for neurosarcoidosis.

CONCLUSION

The study confirms that increased CSF CD4⁺ /CD8⁺ ratio is associated with neurosarcoidosis but cannot alone distinguish the conditions from other neurological diagnoses. However, a ratio below <5 combined with an absence of pleocytosis in CSF yields a negative predictive value (NPV) of 88% suggesting a role for the analysis in differential diagnosing neuroinflammatory conditions.

The Burden of Neurosarcoidosis: Essential Approaches to Early Diagnosis and Treatment

Neurosarcoidosis (NS) is an often severe, destructive manifestation with a likely under-reported prevalence of 5 to 15% of sarcoidosis cases, and in its active phase demands timely treatment intervention. Clinical signs and symptoms of NS are variable and wide-ranging, depending on anatomical involvement. Cranial nerve dysfunction, cerebrospinal parenchymal disease, aseptic meningitis, and leptomeningeal disease are the most commonly recognized manifestations. However, non-organ-specific potentially neurologically driven symptoms, such as fatigue, cognitive dysfunction, and small fiber neuropathy, appear frequently.Heterogeneous clinical presentations and absence of any single conclusive test or biomarker render NS, and sarcoidosis itself, a challenging definitive diagnosis. Clinical suspicion of NS warrants a thorough systemic and neurologic evaluation hopefully resulting in supportive extraneural physical exam and/or tissue findings. Treatment targets the severity of the manifestation, with careful discernment of whether NS reflects active potentially reversible inflammatory granulomatous disease versus inactive postinflammatory damage whereby functional impairment is unlikely to be pharmacologically responsive. Non-organ-specific symptoms are poorly understood, challenging in deciphering reversibility and often identified too late to respond to conventional immunosuppressive/pharmacological treatment. Physical therapy, coping strategies, and stress reduction may benefit patients with all disease activity levels of NS.This publication provides an approach to screening, diagnosis, disease activity discernment, and pharmacological as well as nonpharmacological treatment interventions to reduce disability and protect health-related quality of life in NS.

Retrospective, dual-centre review of imaging findings in neurosarcoidosis at presentation: prevalence and imaging sub-types

AIM

To assess the prevalence of various imaging manifestations in neurosarcoidosis (NS) patients at presentation and to explore if specific imaging findings may cluster in different sub-groups.

MATERIALS AND METHODS

A retrospective, dual-institution, systematic imaging review was undertaken of the magnetic resonance imaging (MRI) findings in 100 consecutive NS patients who presented over a 15-year period. Clustering analysis (k-mode) was performed to evaluate co-occurrence of imaging findings.

RESULTS

Non-enhancing white matter (NEWM) lesions were the most common imaging abnormality (56%), followed by leptomeningeal (47%) and pachymeningeal (32%) involvement. Other common manifestations included cranial nerve involvement (30%), parenchymal granulomas (27%), hypothalamic-pituitary-adrenal axis involvement (26%), and hydrocephalus (14%). Additionally, a higher prevalence of perivascular enhancement (23%), cerebrovascular events (including ischaemic and haemorrhagic events; 17%), and ependymal involvement (20%) were noted than recognised previously. Additional k-mode analysis was performed to explore underlying disease sub-clusters. This was evaluated for clusters varying between two though five (k=2-5). For k=4, the analysis revealed that the imaging findings may possibly be divided into disease sub-sets of four groups, each with varying distribution of imaging manifestations and clinical manifestations.

CONCLUSION

Overall, NEWM lesions and meningeal involvement are the most common imaging manifestations of NS. The prevalence of perivascular enhancement, cerebrovascular events, and ependymal involvement is likely higher than reported previously. Additionally, different imaging findings in NS may cluster together and imaging subtypes in NS possibly exist.

Leptomeningeal Enhancement due to Neurosarcoidosis Mimicking Malignancy

The present report describes the case of a 56-year-old African American man experiencing progressive disequilibrium, lower extremity weakness, difficulty walking, and hearing loss. Brain magnetic resonance imaging showed leptomeningeal enhancement. Initial differential diagnosis was broad, including malignant, infectious, and inflammatory etiologies. The cerebrospinal fluid analyses demonstrated lymphocytic pleocytosis, hypoglycorrhachia, and hyperproteinorrachia but no other abnormalities. An extensive infectious disease workup was negative. Positron emission tomography revealed hypermetabolic lymph nodes in the right mediastinum and right hilum, correlating with findings on endobronchial ultrasonography. Subsequently, image-guided fine-needle aspiration of the right upper paratracheal lymph node was performed, and biopsy studies showed noncaseating granulomatous inflammation. Based on the clinical picture, the diagnosis of neurosarcoidosis was made, and high-dose steroids were started and resulted in significant improvement.

Neurosarcoidosis in a public safety net hospital: a study of 82 cases

Objective

To characterize clinical presentation, laboratory and imaging data, and treatment outcomes for neurosarcoidosis in an urban safety net hospital.

Methods

The research database of Cook County Health and Hospitals system was queried for all cases of sarcoidosis from 2006 to 2013. These cases plus those identified through a survey of neurology faculty were reviewed and flagged if suspected to be neurosarcoidosis. Data were extracted in a standardized fashion, upon review by two experienced neurologists; patients were classified as definite, probable or possible neurosarcoidosis. Disagreements on classification were resolved by consensus conference.

Results

1706 cases of sarcoidosis were identified, with 82 (4.8%) classified as neurosarcoidosis. The cohort was predominantly African American (89%). Six were classified as definite, 34 as probable, and 42 as possible neurosarcoidosis. Neurosarcoidosis was the presenting symptom of sarcoidosis in 74% of cases. The most common presenting phenotype was myelopathy (21.7%), followed by optic nerve/chiasm involvement (16.0%) and epilepsy (11.3%). The facial nerve was involved in only 2% of cases. Chest x-ray showed abnormalities of sarcoidosis in 43.3% of cases, while chest CT did so in 78.6%. Corticosteroids were the initial treatment in 91% of cases, and outcomes were good in 53% of cases.

Conclusion

Neurosarcoidosis remains a challenging diagnosis with the majority of patients without a previous diagnosis of systemic sarcoidosis. Chest imaging was supportive of the diagnosis in a majority of patients. Our cohort differs from others in the literature due to a low prevalence of facial nerve involvement. Prospective registry studies are needed.

Bell's Palsy

PURPOSE OF REVIEW

Bell's palsy is a common outpatient problem, and while the diagnosis is usually straightforward, a number of diagnostic pitfalls can occur, and a lengthy differential diagnosis exists. Recognition and management of Bell's palsy relies on knowledge of the anatomy and function of the various motor and nonmotor components of the facial nerve. Avoiding diagnostic pitfalls relies on recognizing red flags or features atypical for Bell's palsy, suggesting an alternative cause of peripheral facial palsy.

RECENT FINDINGS

The first American Academy of Neurology (AAN) evidence-based review on the treatment of Bell's palsy in 2001 concluded that corticosteroids were probably effective and that the antiviral acyclovir was possibly effective in increasing the likelihood of a complete recovery from Bell's palsy. Subsequent studies led to a revision of these recommendations in the 2012 evidence-based review, concluding that corticosteroids, when used shortly after the onset of Bell's palsy, were "highly likely" to increase the probability of recovery of facial weakness and should be offered; the addition of an antiviral to steroids may increase the likelihood of recovery but, if so, only by a very modest effect.

SUMMARY

Bell's palsy is characterized by the spontaneous acute onset of unilateral peripheral facial paresis or palsy in isolation, meaning that no features from the history, neurologic examination, or head and neck examination suggest a specific or alternative cause. In this setting, no further testing is necessary. Even without treatment, the outcome of Bell's palsy is favorable, but treatment with corticosteroids significantly increases the likelihood of improvement.

Clinical features and prognostic factors of spinal cord sarcoidosis: a multicenter observational study of 20 BIOPSY-PROVEN patients

Sarcoidosis of the spinal cord is a rare disease. The aims of this study are to describe the features of spinal cord sarcoidosis (SCS) and identify prognostic markers. We analyzed 20 patients over a 20-year period in 8 French hospitals. There were 12 men (60 %), mostly Caucasian (75 %). The median ages at diagnosis of sarcoidosis and myelitis were 34.5 and 37 years, respectively. SCS revealed sarcoidosis in 12 patients (60 %). Eleven patients presented with motor deficit (55 %) and 9 had sphincter dysfunction (45 %). The median initial Edmus Grading Scale (EGS) score was 2.5. The cerebrospinal fluid (CSF) showed elevated protein level (median: 1.00 g/L, interquartile range (IQR) 0.72-1.97), low glucose level (median 2.84 mmol/L, IQR 1.42-3.45), and elevated white cell count (median 22/mm(3), IQR 6-45). The cervical and thoracic cords were most often affected (90 %). All patients received steroids and an immunosuppressive drug was added in 10 cases (50 %). After a mean follow-up of 52.1 months (range 8-43), 18 patients had partial response (90 %), 7 displayed functional impairment (35 %), and the median final EGS score was 1. Six patients experienced relapse (30 %). There was an association between the initial and the final EGS scores (p = 0.006). High CSF protein level showed a trend toward an association with relapse (p = 0.076). The spinal cord lesion was often the presenting feature of sarcoidosis. Most patients experienced clinical improvement with corticosteroids and/or immunosuppressive treatment. The long-term functional prognosis was correlated with the initial severity.

Challenges in the diagnosis and treatment of neurosarcoidosis

The diagnosis and treatment of neurosarcoidosis can be very challenging for several reasons. It affects clinically 5%-10% of sarcoidosis patients, but can be found in up to 25% of autopsies. These data reveal that a high percentage of asymptomatic or misdiagnosed cases can be missed at an initial diagnostic approach. Clinical and imaging findings are often non-specific since they can be found in a large number of neurological disorders. Histopathology can also be confounding if not performed by an expert pathologist and not placed in an appropriate clinical context. In this review, we discuss clinical features, laboratory findings, imaging, and histology of neurosarcoidosis, and we report current evidence regarding drug therapy. We conclude that a correct diagnostic approach should include a multidisciplinary evaluation involving clinicians, radiologists, and pathologists and that future studies should evaluate the genetic signature of neurosarcoidosis as they could be helpful in the assessment of this uncommon disease. With head-to-head comparisons of medical treatment for neurosarcoidosis still lacking due to the rarity of the disease and an increasing number of immunomodulating therapies at hand, novel therapeutic approaches are to be expected within the next few years.