Histopathology of central nervous system lesions in Behçet's disease

Neuro-Behçet leading to coma: A case report

Neuro-Behçet disease is often difficult to diagnose due to its complex and severe clinical presentation. This article reports the case of a 35-year-old female patient with a history of Behçet's disease, admitted for a deep coma. Brain MRI performed upon admission revealed extended lesions in the basal ganglia, thalami, and midbrain, along with leptomeningeal contrast enhancement in the temporal region, suggesting meningoencephalitis compatible with parenchymal involvement of neuro-Behçet's disease. Following a comprehensive negative evaluation for infectious and malignant causes, combined with the patient's medical history, a diagnosis of neuro-Behçet disease was established.

The Involvement of Glial Cells in Blood-Brain Barrier Damage in Neuroimmune Diseases

The blood-brain barrier and glial cells, particularly astrocytes, interact with each other in neuroimmune diseases. In the inflammatory environment typical of these diseases, alterations in vascular endothelial cell surface molecules and weakened cell connections allow immune cells and autoantibodies to enter the central nervous system. Glial cells influence the adhesion of endothelial cells by changing their morphology and releasing various signaling molecules. Multiple sclerosis has been the most studied disease in relation to vascular endothelial and glial cell interactions, but these cells also significantly affect the onset and severity of other neuroimmune conditions, including demyelinating and inflammatory diseases. In this context, we present an overview of these interactions and highlight how they vary across different neuroimmune diseases.

Neuro-Behçet's disease: A review

Behcet disease (BD) is a systemic vasculitis which can involve many different organ systems. Neurological involvement (NBD) occurs in 5.3% to 59% of BD patients. The diagnosis is challenging especially in case of inaugural neurological presentation, and is based on a constellation of clinical, laboratory, and neuroimaging findings. NBD can be subdivided into parenchymal NBD through an immune mediated meningoencephalitis with a predilection to the brainstem, basal ganglia, thalamus, cranial nerves, and spinal cord involvement, and extraparenchymal NBD encompassing cerebral veinous thrombosis and intracranial arterial involvement. Brain magnetic resonance shows ill-defined areas of oedema with high signal intensity on T2-FLAIR images, isointense or hypointense in T1-weighted images in the basal ganglia area or in the brainstem, which may extend to the diencephalic structures. Swelling might be noticed. Hemorrhages can be seen, such as contrast enhancement (blood brain barrier disruption). Magnetic resonance venography and computerized tomographic angiography can be used to diagnose extraparenchymal NBD. Treatment of parenchymatous forms is based on glucocorticoids associated with oral immunosuppressants (azathioprine, mycophenolate mofetil or methotrexate) in mild forms, and intravenous cyclophosphamide or infliximab in severe forms. The management of cerebral thrombosis consists of steroids course associated with an oral anticoagulation. An early recognition of this condition is mandatory to initiate adequate therapies in order to improve outcomes and limit the risk of sequelae, relapses, or death. The aim of this review is to summarize a comprehensive review on the various neurological presentations of BD with emphasizes on diagnostic tools, prognosis, and therapeutic issues.

Diffusion tensor imaging in Behcet's disease with and without neurological involvement patients: evaluation of microstructural white matter abnormality with a tract-based spatial statistical analysis

OBJECTIVE

This study aims to assess the microstructural abnormalities in white matter (WM) among Behcet's disease (BD) patients, both with and without neurological involvement, utilising tract-based spatial statistics (TBSS) to elucidate the underlying causes of WM microstructural changes.

METHODS

This prospective study comprised 43 BD patients without neurological involvement, 15 neuro-Behcet's disease (NBD) patients with normal conventional MRI, and 54 healthy controls matched for age and sex. TBSS was applied in this diffusion tensor imaging study to conduct a whole-brain voxel-wise analysis of fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AD), and radial diffusivity (RD) of WM.

RESULTS

Compared to the control group, BD patients exhibited decreased FA and increased MD and RD in nearly all WM tracts, along with increased AD in the left corticospinal tract (CST), left inferior longitudinal fasciculus (ILF), and left superior longitudinal fasciculus (SLF). NBD patients also showed a widespread decrease in FA and increased MD and RD, similar to BD patients without neurological involvement. Additionally, NBD patients had increased AD in the left CST, left ILF, left SLF, left inferior fronto-occipital fasciculus (IFOF), and right CST. Compared to BD patients without neurological involvement, NBD patients exhibited a greater reduction in FA and an increase in MD and RD in WM tracts, with no significant differences in AD.

CONCLUSION

These results suggest that the main mechanism of microstructural changes in the WM of BD patients may be related to impaired fibre integrity, demyelination, and decreased myelin sheath integrity.

ADVANCES IN KNOWLEDGE

This study demonstrated BD patients without neurological involvement and NBD patients a decrease in FA and an increase in MD and RD were observed in larger areas of major WM tracts, while an increase in AD values was observed in fewer tracts. Our findings may be useful in understanding the pathophysiology underlying subclinical parenchymal involvement and neurological dysfunction in BD patients and the management of BD patients.

Cerebral infarction in Behçet's syndrome caused by obliterative focal arteritis

We present a case in which cerebral infarction was seen and Behcet's syndrome was diagnosed. Following investigation and monitoring, we identified that the cause was a progressive obliterative focal arteritis of the middle cerebral artery. Such an entity has not previously been reported, although similar cases are described which explain the pathophysiology of the disorder.

Cerebrospinal Fluid Analysis in Rheumatological Diseases with Neuropsychiatric Complications and Manifestations: A Narrative Review

The analysis of cerebrospinal fluid (CSF) remains a valuable diagnostic tool in the evaluation of inflammatory and infectious conditions involving the brain, spinal cord, and meninges. Since many rheumatic inflammatory diseases can involve the central and peripheral nervous system, the aims of this narrative review were to summarize the latest evidence on the use of CSF analysis in the field of neuropsychiatric manifestations of rheumatic diseases. Routine CSF parameters were taken into consideration for this review: appearance; total protein and cellular content (pleocytosis); lactate and/or glucose; CSF/serum albumin quotient; intrathecal synthesis of IgG. Data regarding the role of CSF analysis in the clinical management of neuropsychiatric systemic lupus erythematosus, primary Sjogren's syndrome, rheumatoid arthritis, and Behçet's syndrome are presented. Although no disease-specific picture has been identified, CSF analysis remains a useful diagnostic tool to confirm the presence of a neuro-inflammatory state or, conversely, to exclude the concomitant presence of other inflammatory/infectious diseases affecting the CNS in the context of systemic rheumatologic conditions.

The role of Interleukin-21 in autoimmune Diseases: Mechanisms, therapeutic Implications, and future directions

IL-21 is a multifunctional cytokine that regulates the functional activity of various immune cells. Initial studies have shown that IL-21 can influence the differentiation, proliferation and function of T and B cells, as well as promote the maturation and increase the cytotoxicity of CD8 + T cells and NK cells. During humoral immune responses, IL-21 has significant effects on B cell activation, differentiation and apoptosis. In addition, IL-21 promotes the differentiation of both naive and memory B cells, ultimately leading to the activation of plasma cells. The function of IL-21 in the immune system is complex, as it has the ability to either stimulate or inhibit immune responses. in addition, IL-21 facilitates the differentiation of naive and memory B cells into plasma cells. The functionality of IL-21 in the immune system is diverse, as it has the ability to stimulate or inhibit immune responses. This cytokine has been implicated in several diseases including cancer, allergies and autoimmune diseases. Research has suggested that this cytokine is involved in the development of autoimmune diseases such as systemic lupus erythematosus and rheumatoid arthritis. Several studies have suggested that inhibition of IL-21 has a therapeutic effect on autoimmune diseases. Therefore, targeting both the cytokine's receptor and IL-21 in autoimmune diseases may be an effective approach to reduce the severity of the disease or to treat it. This review will examine the biological effects of IL-21 on various immune cells and the role of the cytokine in autoimmune diseases.

Neurological involvement by Behçet's syndrome: clinical features, diagnosis, treatment and outcome

Neurological involvement in Behçet's syndrome arises predominately through an inflammatory meningoencephalitis characterised by perivenular inflammation due to activation of Th-17 immunological pathways. The brainstem is involved in 50% of cases, the diencephalon and other areas of the brain in 30%, and the spinal cord in 10%. Movement disorders and epilepsy may occur. Psychiatric syndromes may arise with brain and brainstem involvement, and cognitive disorders relate to the brain disease, to circulating inflammatory factors, and to fatigue and despondency. Eighty per cent of cases begin with a relapsing disease course, of whom 70% have only one attack, and 30% have a progressive disease course either from onset or following an initially relapsing course. Venous thrombosis leading to intracranial hypertension and cerebral venous infarction is less common and caused by inflammation in affected veins and a circulating prothrombotic state. Arterial involvement is rare and relates to an arteritis affecting large-sized and medium-sized vessels within the brain leading to infarction, subarachnoid and parenchymal haemorrhage, aneurysm formation and arterial dissection. There is a newly recognised disorder of cerebral cortical hypoperfusion. Cranial neuropathy, peripheral neuropathy and myositis are rare. There has been significant progress in understanding the pathophysiology and treatment of the systemic disease, leading to improved outcomes, but there has been no randomised trial of treatment in the neurological disorder.

Neuro-Behçet With a Thalamic Lesion: A Case Report

Behçet's disease (BD) is an autoimmune disease characterized by multisystemic variable-vessel vasculitis and oral, genital, and intestinal ulcers. Neurological involvement or "Neuro-Behçet" (NB) manifests due to parenchymal inflammation. We present the case of a 21-year-old male with a five-year-old history of intermittent chronic oral and genital ulcers who presented with headache, right hemiparesis, progressive loss of visual acuity, and a thalamic tumor-like lesion on magnetic resonance imaging (MRI). A brain biopsy showed multiple perivascular infarcts associated with vasculitis affecting arterioles, venules, and capillaries.

[Diagnosis and Treatment of Neuro-Behçet: A Clinical Update]

Behçet's disease is a relapsing multisystemic inflammatory syndrome characterized by recurrent oral and/or genital ulcers, uveitis, arthritis, skin lesions, and gastrointestinal and neurological involvement. Neuro-Behçet corresponds to nervous system involvement and is one of the most severe complications of Behçet disease. It occurs in 3% to 30% of cases and is categorized into parenchymal (most common) or non-parenchymal disease. The most common manifestation of parenchymal neuro-Behçet is meningoencephalitis with involvement of the brainstem, where patients present with cranial neuropathies, encephalopathy, sensory-motor syndromes, epilepsy, or myelitis. The main non-parenchymal manifestation is cerebral venous thrombosis. Neuro-Behçet has a predominantly subacute course, with remission within weeks, or clinical progression in one third of the cases. The diagnosis is essentially clinical and diagnostic tests help to corroborate the suspicion, distinguish from differential diagnoses, and exclude complications. Brain magnetic resonance imaging allows the identification of acute lesions (hypointense or isointense on T2-weighted and hypointense on T1-weighted sequences) contrast-enhanced, and chronic lesions characterized by non-contrast enhanced small lesions and brainstem atrophy. If non-parenchymal involvement is suspected, cerebral veno-magnetic resonance imaging /computed tomography should be performed. Cerebrospinal fluid shows elevated proteinorachia and pleocytosis in parenchymal and no changes in non-parenchymal neuro-Behçet (except increased opening pressure). Outbursts of parenchymal disease should be treated with high dose intravenous corticosteroid therapy, with subsequent switch to oral corticoids, followed by biologic therapy, usually an anti-TNF. The treatment of cerebral venous thrombosis is controversial and may consist of a combination of corticosteroids and anticoagulation.

Single-cell analyses highlight the proinflammatory contribution of C1q-high monocytes to Behçet's disease

Behçet's disease (BD) is a chronic vasculitis characterized by systemic immune aberrations. However, a comprehensive understanding of immune disturbances in BD and how they contribute to BD pathogenesis is lacking. Here, we performed single-cell and bulk RNA sequencing to profile peripheral blood mononuclear cells (PBMCs) and isolated monocytes from BD patients and healthy donors. We observed prominent expansion and transcriptional changes in monocytes in PBMCs from BD patients. Deciphering the monocyte heterogeneity revealed the accumulation of C1q-high (C1q^hi) monocytes in BD. Pseudotime inference indicated that BD monocytes markedly shifted their differentiation toward inflammation-accompanied and C1q^hi monocyte-ended trajectory. Further experiments showed that C1q^hi monocytes enhanced phagocytosis and proinflammatory cytokine secretion, and multiplatform analyses revealed the significant clinical relevance of this subtype. Mechanistically, C1q^hi monocytes were induced by activated interferon-γ (IFN-γ) signaling in BD patients and were decreased by tofacitinib treatment. Our study illustrates the BD immune landscape and the unrecognized contribution of C1q^hi monocytes to BD hyperinflammation, showing their potential as therapeutic targets and clinical assessment indexes.

Biologic therapy in refractory Neurobehçet's disease: a multicenter study of 41 patients and literature review

OBJECTIVES

To assess efficacy and safety of biologic therapy (BT) in Neurobehçet's disease (NBD) refractory to glucocorticoids and at least one conventional immunosuppressive drug.

METHODS

Open-label, national, multicenter study. NBD diagnosis was based on the International Consensus Recommendation criteria. Outcome variables were efficacy and safety. Main efficacy outcome was clinical remission. Other outcome variables analyzed were glucocorticoid-sparing effect and improvement in laboratory parameters.

RESULTS

We studied 41 patients (21 women; age 40.6±10.8 years). Neurological damage was parenchymal (n = 33, 80.5%) and non-parenchymal (n = 17, 41.5%). First BTs used were infliximab (n = 19), adalimumab (n = 14), golimumab (n = 3), tocilizumab (n = 3) and etanercept (n = 2). After 6 months of BT, neurological remission was complete (n = 23, 56.1%), partial (n = 15, 37.6%), no response (n = 3, 7.3%). In addition, mean dose of oral prednisone decreased from 60 [30-60] mg/day at the initial visit to 5 [3.8-10] mg/day after 6 months, p < 0.001). It was also the case for mean erythrocyte sedimentation rate (31.5±25.6 to 15.3±11.9 mm/1st hour, p = 0.005) and median [IQR] C-reactive protein (1.4 [0.2-12.8] to 0.3 [0.1-3] mg/dL, p = 0.002). After a mean follow-up of 57.5 months, partial or complete neurological remission persisted in 37 patients (90.2%). BT was switched in 22 cases (53.6%) due to inefficacy (n = 16) or adverse events (AEs) (n = 6) and discontinued due to complete prolonged remission (n = 3) or severe AE (n = 1). Serious AEs were observed in 2 patients under infliximab treatment.

CONCLUSIONS

BT appears to be effective and relatively safe in refractory NBD.

Headache and immunological/autoimmune disorders: a comprehensive review of available epidemiological evidence with insights on potential underlying mechanisms

Several lines of evidence support a role of the immune system in headache pathogenesis, with particular regard to migraine. Firstly, alterations in cytokine profile and in lymphocyte subsets have been reported in headache patients. Secondly, several genetic and environmental pathogenic factors seem to be frequently shared by headache and immunological/autoimmune diseases. Accordingly, immunological alterations in primary headaches, in particular in migraine, have been suggested to predispose some patients to the development of immunological and autoimmune diseases. On the other hand, pathogenic mechanisms underlying autoimmune disorders, in some cases, seem to favour the onset of headache. Therefore, an association between headache and immunological/autoimmune disorders has been thoroughly investigated in the last years. The knowledge of this possible association may have relevant implications in the clinical practice when deciding diagnostic and therapeutic approaches. The present review summarizes findings to date regarding the plausible relationship between headache and immunological/autoimmune disorders, starting from a description of immunological alteration of primary headaches, and moving onward to the evidence supporting a potential link between headache and each specific autoimmune/immunological disease.

Binucleated and Multinucleated Neurons are Formed by Fusion

In the era of molecular biology and atomic force microscopy, some important macroscopic issues such as simultaneous bidirectional axonal flow or neuronal multinucleosis remain unaddressed. However, these issues have to be addressed, because they distort the results of our current achievements. Using videorecording technique, we studied adhesive contacts between neurons and their processes and kinetics of anastomosis retraction between the cell bodies up to their complete fusion with introduction of neurites into the cell cytoplasm and formation of binuclear cells. Three proofs refuting the mechanism of binuclearity formation by amitosis are presented. Live trinuclear neurons without signs of amitotic division were identified. Electron microscopy showed that fusion of many living neurons into one simplest during centrifugation of isolated cells.

Case Report: Repeated Low-Dose Rituximab Treatment Is Effective in Relapsing Neuro Behçet's Disease

Neuro Behçet's disease (NBD) is a rare but most aggressive manifestation of Behçet's disease (BD) with a poor prognosis, and some patients even present a relapsing and treatment-resistant progressive course. In some relapsing NBD cases, traditional corticosteroids and immunosuppressive drugs show limited efficacy, while benefits of biological agents, such as anti-B-lymphocyte CD20 biological agent rituximab (RTX), gradually represent potential therapeutic advantages with clinical rapid remission and long-time maintenance. However, up to now, the optimal dosage of RTX in NBD is still elucidated. Here, we report two patients with relapsing NBD, despite continuous high dose steroids and sufficient azathioprine treatment, still presenting severe and relapsing meningoencephalitis or brainstem involvement. Repeated low-dose RTX (100 mg × 3/1 week apart, 100 mg repeated every 6 months) is then attempted with rapid recovery and sustained remission. The approach in our cases may expand therapeutic options and provide helpful references for relapsing NBD treatment.

Behçet's Syndrome Apart From the Triple Symptom Complex: Vascular, Neurologic, Gastrointestinal, and Musculoskeletal Manifestations. A Mini Review

Behçet‘s Syndrome (BS) is a variable vessel vasculitis according to the Chapel Hill Consensus Nomenclature (1) and may thus affect any organ, including major and minor arterial and venous vessels to a varying degree and with varying frequency. Although the main features of BS are recurrent oral and genital aphthous ulcers, cutaneous lesions, ocular inflammation and arthritis—major vessel and life—or organ threatening involvement of internal organs and the central and peripheral nervous system occur. In general, BS in Europe appears to form six phenotypes of clinical manifestations (2), which are (1) mucocutaneous only, (2) predominant arthritis/articular involvement, (3) vascular phenotype, (4) ocular manifestations, which are most likely associated with CNS manifestations and HLA-B51, (5) dominant parenchymal CNS manifestations (being associated with the ocular ones), and (6) gastrointestinal involvement. Mucocutaneous manifestations are present in almost all patients/all phenotypes. In the following review, we summarize the current knowledge concerning vascular, neurologic, gastrointestinal and musculoskeletal manifestations of the disease.

Regulatory T cell/Th17 balance in the pathogenesis of pediatric Behçet disease

OBJECTIVES

Behçet disease (BD) is a chronic systemic inflammatory disorder of unknown aetiology. The aim of this study was to determine the orientation of T cell subpopulations in pediatric BD and more precisely to look for a regulatory T lymphocytes (Tregs)/Th17 imbalance.

METHODS

T cell subpopulations were analyzed by flow cytometry in the peripheral blood of pediatric patients with acute (aBD, n = 24), remitting (rBD, n = 12) BD, and in healthy controls (HC, n = 24). Tregs (CD4+CD25hiCD127-/loFoxp3+), activated Tregs (GITR, LAP, CTLA-4, and HLA-DR expression), CD4+ and CD8+ T cells producing interferon-g (Th1 and Tc1) or interleukin (IL)-17 (Th17 and Tc17) under polyclonal (OKT3/IL-2) or antigenic (Streptococcus sanguis KTH-1 peptides and HSP-60) stimulation, were numerated.

RESULTS

Th17 (1.9 and 5.1 fold) and Tc17 (4.0 and 2.0 fold) frequency under mitogenic stimulation was significantly increased in aBD and rBD patients as compared with HC. Th17 frequency under antigenic stimulation was also higher in patients than in HC. The percentage and number of Tregs and activated Tregs in patients and in HC were similar. However, when Tregs were removed, antigen-driven differentiation into Th1 and Th17 was significantly boosted in BD but not in HC CD4+T cells.

CONCLUSION

There is a bias toward a Th17 polarization in acute and remitting BD children. Although we did not observe an increase in the number of Tregs in these patients, their Tregs limit CD4+T cell differentiation into Th1 and Th17 cells. Thus, in pediatric BD, Tregs seem to incompletely counterbalance a Th17 orientation of the helper T cell response.

Width of the third ventricle as a highly-sensitive biomarker in chronic progressive neuro-Behçet's disease

Chronic progressive neuro-Behçet's disease (CPNBD) is characterized by slowly progressive cognitive decline, cerebellar ataxia, and brainstem atrophy without acute encephalomeningitis. To evaluate the progression of CPNBD during treatment, we conducted a retrospective, longitudinal comparative analysis of the clinical features and brain magnetic resonance imaging (MRI) in patients with CPNBD. We classified participants into three groups: NBD with acute encephalomeningitis alone (Group A, 8 patients with acute neuro-Behçet's disease [ANBD]), primary progressive CPNBD (Group B, 3 patients), and a combination of acute encephalomeningitis, and chronic progression (Group C, 2 patients). Routine laboratory tests and monthly rate of enlargement of the width of the third ventricle (ΔWTVm) and relative value of ΔWTVm to the transverse cerebral diameter (ΔWTVIm) were statistically evaluated. Although higher cell count values and interleukin-6 concentration in the cerebrospinal fluid were observed in ANBD, both ΔWTVm (p = 0.008) and ΔWTVIm (p = 0.008) were significantly larger in CPNBD phase than in the ANBD phase. Effective treatment for CPNBD seemed to reduce ΔWTVm and ΔWTVIm in some patients. Sequential evaluation of WTV in patients with CPNBD is a highly sensitive candidate biomarker of early diagnosis and treatment efficacy.

Tocilizumab in the treatment of severe and refractory parenchymal neuro-Behçet's syndrome: case series and literature review

OBJECTIVES

This study aimed to investigate the efficacy and safety of tocilizumab (TCZ) in severe and refractory parenchymal neuro-Behçet's syndrome (p-NBS).

METHODS

We retrospectively analyzed five patients with p-NBS treated with TCZ in our center between 2013 and 2020, and six cases from literature research with the index terms "neuro-Behçet's syndrome" and "tocilizumab" on PubMed NCBI.

RESULTS

A total of 11 patients with p-NBS were enrolled (5 males, 6 females), with a mean age of 34.5 ± 8.0 years at the onset. All the patients had parenchymal neurological lesions, six patients (54.5%) suffered from multiple lesions, and nine patients (81.8%) were disabled. Before TCZ administration, all the patients had failed conventional therapy, eight patients (72.7%) received two or more immunosuppressants, and five patients showed insufficient response or intolerance to other biologics. TCZ was administrated at 8 mg/kg every 4 weeks, with background glucocorticoids (GCs) and immunosuppressants. After a median follow-up of 13 (interquartile range, 3.5-23.5) months, all the patients achieved both clinical and radiological improvements, and the Behçet's Disease Current Activity Form score improved significantly (3 versus 0, median, p = 0.004), the Rankin score also decreased (4 versus 2, median, p = 0.005). Levels of interleukin-6 in the cerebrospinal fluid decreased significantly in five patients (533.4 ± 389.7 pg/ml versus 34.5 ± 27.1 pg/ml, p = 0.048), after a median of two (interquartile range, 1-4) times of TCZ infusions. Furthermore, the GC dosage (per os) reduced from 69.2 ± 16.9 mg/d to 16.4 ± 16.2 mg/d (p = 0.000), and immunosuppressants were tapered in number and dosage in seven (63.6%) and four (36.3%) patients, respectively. No serious adverse events or deaths were observed during follow-up.

CONCLUSIONS

TCZ is well tolerated and effective in severe and refractory p-NBS, with a favorable GC- and immunosuppressant-sparing effect. Cerebrospinal fluid interleukin-6 might be used to monitor the effects of TCZ in p-NBS.

Behçet disease (BD) and BD-like clinical phenotypes: NF-κB pathway in mucosal ulcerating diseases

Behçet's disease (BD) is a heterogeneous multi-organ disorder in search of a unified pathophysiological theory and classification. The disease frequently has overlapping features resembling other disease clusters, such as vasculitides, spondyloarthritides and thrombophilias with similar genetic risk variants, namely HLA-B*51, ERAP1, IL-10, IL-23R. Many of the BD manifestations, such as unprovoked recurrent episodes of inflammation and increased expression of IL-1, IL-6 and TNFα, overlap with those of the hereditary monogenic autoinflammatory syndromes, positioning BD at the crossroads between autoimmune and autoinflammatory syndromes. BD-like disease associates with various inborn errors of immunity, including familial Mediterranean fever, conditions related to dysregulated NF-κB activation (eg TNFAIP3, NFKB1, OTULIN, RELA, IKBKG) and either constitutional trisomy 8 or acquired trisomy 8 in myelodysplastic syndromes. We review here the recent advances in the immunopathology of BD, BD-like diseases and the NF-κB pathway suggesting new elements in the elusive BD etiopathogenesis.

Neuro-Behcet's disease: An update on diagnosis, differential diagnoses, and treatment

Neuro-Behcet's disease (NBD) is defined as a combination of neurologic symptoms and/or signs in a patient with Behcet's disease (BD). Relevant syndromes include brainstem syndrome, multiple-sclerosis like presentations, movement disorders, meningoencephalitic syndrome, myelopathic syndrome, cerebral venous sinus thrombosis (CVST), and intracranial hypertension. Central nervous involvement falls into parenchymal and non-parenchymal subtypes. The parenchymal type is more prevalent and presents as brainstem, hemispheric, spinal, and meningoencephalitic manifestations. Non-parenchymal type includes CVST and arterial involvement. Perivascular infiltration of polymorphonuclear and mononuclear cells is seen in most histo-pathologic reports. In parenchymal NBD, cerebrospinal fluid (CSF) generally exhibits pleocytosis, increased protein and normal glucose. In NBD and CVST, CSF pressure is increased but content is usually normal. The typical acute NBD lesions in brain magnetic resonance imaging (MRI) are mesodiencephalic lesions. The pattern of extension from thalamus to midbrain provides a cascade sign. Brain MRI in chronic NBD usually shows brain or brainstem atrophy and/or black holes. The spinal MRI in the acute or subacute myelopathies reveals noncontiguous multifocal lesions mostly in cervical and thoracic lesions. In chronic patients, cord atrophy can also be seen. Brain MRI (particularly susceptibility-weighted images), MR venography (MRV) and computerized tomographic venography (CTV) can be used to diagnose CVST. Parenchymal NBD attacks can be treated with glucocorticoids alone or in combination with azathioprine. For patients with relapsing-remitting or progressive courses, shifting to more potent immunosuppressive drugs such as mycophenolate, methotrexate, cyclophosphamide, or targeted therapy is warranted. For NBD and CVST, immunosuppressive drugs with or without anticoagulation are suggested.

The Clinical Features and Risk Factors of Parenchymal Neuro-Behcet's Disease

To investigate the clinical features of parenchymal neuro-Behcet's disease (p-NBD), we retrospectively reviewed the medical records of 1009 BD patients admitted to Peking Union Medical College Hospital from 2000 to 2016. Forty-two patients (25 males and 17 females) with p-NBD and eighty-four age- and sex-matched BD patients without neurological involvement who were served as controls were enrolled. Neurological onset was concomitant with the onset of BD in six cases (14.3%). Pyramidal signs (50.0%) and headache (33.3%) were the most common manifestations. On MRI, the lesions were mainly in the midline structures and hyperintense in the T2-weighted image. The most common lesion was the brainstem (54.8%). Spinal cord involvement was observed in five cases, four of which with cervical cord involvement. Multifocal lesions were observed in 13 patients. Ocular involvement was more prevalent in p-NBD (35.7%) (P = 0.041, OR = 2.36, 95% CI = 1.03-5.44) compared with controls. All patients received corticosteroids and immunosuppressants, mainly cyclophosphamide (39/42). Six patients with severe/refractory condition received biological agents and achieved response measured by decreased Rankin score (P = 0.002). With a median follow-up of 28 months, 22 patients (61.1%) achieved clinical improvements, while 10 (27.8%) relapsed and 4 died (mortality rate 11.1%). p-NBD is a rare yet disabling and life-threatening complication of BD. Ocular involvement is a risk factor for p-NBD. Promptly aggressive treatment is essential for improving prognosis, and biological agents might be a promising approach for severe/refractory p-NBD.

Unclassified Vasculitis with Episcleritis, Thrombophlebitis, Deep Vein Thrombosis, Pulmonary Vasculitis, and Intracranial Vasculitis: An Autopsy Case Report

BACKGROUND Systemic vasculitides constitute heterogenous conditions affecting many organs and systems through blood vessel inflammation. Although there are some classifications for vasculitis, several vasculitides are "unclassified" because they cannot be clearly assigned to one of the known entities. CASE REPORT We report an autopsy case of a 67-year-old Japanese man who presented with fever, ocular pain, erythema, chest pain, and headache. The disease caused episcleritis, thrombophlebitis, extensive deep vein thrombosis, multiple pulmonary nodules and masses, hypertrophic pachymeningitis, and hyper-intensity areas in brain parenchyma on magnetic resonance images. Histopathology of the pulmonary nodule confirmed vasculitis affecting medium-to-small veins and arteries without necrotizing vasculitis or granulomatous inflammation. We diagnosed the patient with unclassified vasculitis based on the clinicopathological characteristics. Steroids in combination with immunosuppressants were used, but the disease was refractory and relapsing. The disease activity was eventually controlled with rituximab, but the patient died of bronchopneumonia. On autopsy, lung and brain findings indicated healed vascular inflammation. CONCLUSIONS This is the first case report of unclassified vasculitis, which is characterized as medium-to-small-sized arteritis and phlebitis, causing episcleritis, thrombophlebitis, deep vein thrombosis, pulmonary vasculitis, and intracranial vasculitis. The clinical conditions share some similarities with granulomatosis with polyangiitis and Behçet's disease; however, they meet no classification criteria of any specific vasculitis. More cases need to be analyzed to confirm our findings.

Neurological Involvement in Primary Systemic Vasculitis

Primary systemic vasculitis can affect every structure in both the central and peripheral nervous system, causing varied neurological manifestations of neurological dysfunction. Early recognition of the underlying causes of the neurological symptoms can facilitate timely treatment and improve the prognosis. This review highlights the clinical manifestations of primary systemic vasculitis in the nervous system.

Localized atrophy of the pontine base as a sequela of prolonged ischemia: Report of an autopsy case

An 80-year-old man with a history of diabetes mellitus and hypertension died of a progressive neurological disorder characterized by truncal ataxia, extraocular movement disturbance, and muscular rigidity. Neuroradiological examination showed progressive atrophy restricted to the pontine base. Autopsy revealed localized atrophy of the pontine base, in which both neurons and nerve fibers were lost, especially in the central region. Medium-sized and small arteries in the parenchyma of the pontine base showed marked fibro-hyalinous thickening of the walls with luminal stenosis, but no distinct tissue defect as seen in lacunar infarct was observed. Perivascular lymphocytic infiltration was mostly absent, and reactive astrocytic proliferation was weak. The pontine tegmentum, midbrain, and medulla oblongata were well preserved. Localized atrophy of the pontine base is a rare pathological condition, and its pathogenesis in the present case can be best explained by a prolonged ischemic state (hypoperfusion) due to marked sclerotic changes of perforating arteries. It is unique that the lesions were restricted to the pontine base and the formation of lacunas was not observed. Localized metabolic derangement resembling that seen in central pontine myelinolysis might have also contributed to the pathogenesis of this peculiar localized atrophy.

Blood-brain barrier dysfunction in immuno-mediated neurological diseases

The blood-brain barrier (BBB) is the brain-specific endothelial cell barrier that is important for maintaining brain homeostasis and preventing the entry of toxic substances. Pathological BBB dysfunction is a critical step of the disease process in several immuno-mediated neurological diseases, including multiple sclerosis (MS), neuromyelitis optica (NMO), neuropsychiatric systemic lupus erythematosus (NPSLE) and neuro-Behçet diseases. The pathological findings from patients with secondary progressive (SP) MS, NMO and NPSLE showed leaky BBB in the active lesions. NMO is a disease with strong evidence of disease-specific and pathogenic autoantibodies (aquaporin 4 [AQP4] autoantibodies). In the development of NMO, circulating AQP4 autoantibodies need to pass through the BBB in order to reach AQP4 on the astrocyte endfeet. Strong evidence suggests that NPSLE is associated with the disruption of the BBB and NPSLE patients frequently have antibodies bound to endothelial cells in their sera. We recently identified two BBB-reactive autoantibodies in immuno-mediated neurological diseases: galectin-3 autoantibodies in SPMS and GRP78 autoantibodies in NMO. In the present review article, we describe the basic structure and cellular biology of the BBB, discuss recent insights regarding the pathophysiology of the BBB breakdown in the setting of immuno-mediated neurological diseases, and describe our recent findings of autoantibody-mediated BBB breakdown.

Intracranial Infectious and Inflammatory Diseases Presenting as Neurosurgical Pathologies

There are many infectious and inflammatory processes affecting the central nervous system that can simulate other neurosurgical pathologies (e.g. tumor) and may precipitate a brain biopsy for definitive diagnosis if not suspected a priori. The challenge for the healthcare team is to recognize imaging features that support a nonsurgical pathology to avoid unnecessary interventions. This review aims to give a general overview of some common inflammatory and infectious entities that affect the central nervous system, with illustrative examples and highlighting important pearls and pitfalls.

Central vein sign differentiates Multiple Sclerosis from central nervous system inflammatory vasculopathies

Objectives

In multiple sclerosis (MS), magnetic resonance imaging (MRI) is a sensitive tool for detecting white matter lesions, but its diagnostic specificity is still suboptimal; ambiguous cases are frequent in clinical practice. Detection of perivenular lesions in the brain (the “central vein sign”) improves the pathological specificity of MS diagnosis, but comprehensive evaluation of this MRI biomarker in MS‐mimicking inflammatory and/or autoimmune diseases, such as central nervous system (CNS) inflammatory vasculopathies, is lacking. In a multicenter study, we assessed the frequency of perivenular lesions in MS versus systemic autoimmune diseases with CNS involvement and primary angiitis of the CNS (PACNS).

Methods

In 31 patients with inflammatory CNS vasculopathies and 52 with relapsing–remitting MS, 3‐dimensional T2*‐weighted and T2–fluid‐attenuated inversion recovery images were obtained during a single MRI acquisition after gadolinium injection. For each lesion, the central vein sign was evaluated according to consensus guidelines. For each patient, lesion count, volume, and brain location, as well as fulfillment of dissemination in space MRI criteria, were assessed.

Results

MS showed higher frequency of perivenular lesions (median = 88%) than did inflammatory CNS vasculopathies (14%), without overlap between groups or differences between 3T and 1.5T MRI. Among inflammatory vasculopathies, Behçet disease showed the highest median frequency of perivenular lesions (34%), followed by PACNS (14%), antiphospholipid syndromes (12%), Sjögren syndrome (11%), and systemic lupus erythematosus (0%). When a threshold of 50% perivenular lesions was applied, central vein sign discriminated MS from inflammatory vasculopathies with a diagnostic accuracy of 100%.

Interpretation

The central vein sign differentiates inflammatory CNS vasculopathies from MS at standard clinical magnetic field strengths. Ann Neurol 2018;83:283–294

[A case of chronic progressive neuro-Behçet disease with extensive cerebral atrophy and elevated CSF IL-6 activity treated with infliximab]

A 43-year-old man without a previous episode of uveitis presented with slowly progressive neurological symptoms that appeared within the past year such as dysarthria, ataxic gait, and behavioral changes. Brain MRI findings showed atrophic lesions in the brainstem and cerebellum. Because these clinical symptoms and abnormal MRI findings indicated spinocerebellar degeneration as the initial diagnosis, he was admitted to our hospital. On admission, we noticed that he had non-neurological manifestations of Behçet disease, such as stomatitis, genital ulcers, and folliculitis. HLA-B51 was positive. He also showed pleocytosis (29 cells/mm³, predominantly mononuclear cells) and elevated cerebrospinal fluid (CSF) IL-6 levels (213 pg/ml), hence he was diagnosed with chronic progressive neuro-Behçet disease (CPNBD). The therapeutic effect of a high-dose intravenous methylprednisolone pulse (1,000 mg/day for 3 days) and methotrexate (maximum dosage, 16 mg/week) was poor against both neurological symptoms and CSF findings. Intravenous infliximab therapy (5 mg/kg, 2 weeks) dramatically decreased CSF IL-6 levels (13 pg/ml) but clinical symptoms remained unchanged. MRI findings of extensive cerebral atrophy and increased CSF IL-6 levels at the pretreatment time point reflected irreversible neurological involvement in CPNBD. For cases with progressive psychiatric symptoms and cerebellar ataxia in the early stage of the disease, skin manifestations should be examined immediately, CSF IL-6 levels measured, and immunosuppressive therapy initiated before CPNBD progresses to brainstem atrophy.

Neuro-Behçet disease mimicking brain tumor: A case report

BACKGROUND

Behçet's disease (BD) is an inflammatory multisystem disease with unknown etiology, and consists of a TRIAD comprising recurrent oral ulcers, genital ulcers, and uveitis. In some cases, the disease affects the central nervous system, called Neuro-Behçet Disease (NBD). Few cases of NBD simulating a brain tumor have been previously reported.

CASE DESCRIPTION

Here, we describe the case of a 46-year-old male patient with a previous diagnosis of brain tumor who was later diagnosed for BD.

CONCLUSION

This case highlights the importance of differential diagnosis of lesions with tumoral features. Checking for the possibility of NBD may help avoiding biopsy in these types of cases.

Vasculitis in the autoinflammatory diseases

PURPOSE OF REVIEW

This article addresses the prevalence and relationship between autoinflammatory diseases and vasculitis.

RECENT FINDINGS

Autoimmune diseases (AIDs) are a group of syndromes characterized by episodes of unprovoked inflammation due to dysregulation of the innate immune system. Despite the common occurrence of rashes and other skin lesions in these diseases, vasculitis is reported in only a few. On the other hand, neutrophilic dermatoses are more prevalent. Large vessel vasculitis is reported in patients with Behcet's and Blau's syndromes. Small and medium size vasculitides are reported in familial Mediterranean fever mainly as Henoch-Schonlein purpura and polyarteritis nodosa, respectively. It is rarely described in hyper IgD with periodic fever syndrome, cryopyrin associated periodic syndromes, TNF receptor-associated periodic syndrome, deficiency of interleukin-1 receptor antagonist and pyoderma gangrenosum and acne syndrome. In most AID where bones and skin are mainly involved (CRMO, Majeed syndrome, Cherubism and DITRA) - vasculitis has not been described at all. In AID small vessel vasculitis affects mainly the skin with no involvement of internal organs.

SUMMARY

In AID, neutrophilic dermatoses are more common and prominent than vasculitis. This may reflect a minor role for interleukin-1 in the pathogenesis of vasculitis. The rarity of vasculitis in AID suggests that in most reported cases its occurrence has been probably coincidental rather than being an integral feature of the disease.

Neurological complications of Behçet's syndrome

In this review of the neurological complications of Behçet's syndrome, the clinical features and epidemiology of the systemic disease are summarised before a discussion of the neurological syndromes which may develop is made. Neurological involvement occurs in 9% of cases, and is equally prevalent in each geographical area. Vascular complications occur in 14%, in whom thrombosis of the venous sinuses or cerebral veins occurs, and intracranial hypertension, venous infarction and parenchymal haemorrhage may develop. There is a correlation with the prevalence of peripheral venous thrombosis. Concurrent inflammatory disease of the brain is most uncommon. Inflammation may affect any part of the central nervous system, but most commonly involves a subacute meningoencephalitis of the brainstem and diencephalon. Inflammatory lesions elsewhere in the brain and in the spinal cord may occur, and tumefactive lesions may arise from the diencephalon. Cognitive dysfunction and affective symptoms, including psychosis, may occur, and there are high levels of anxiety and fatigue which are related to the severity of the systemic disease, all of which are more severe in those with neurological involvement. Imaging shows enhancing lesions which often disappear after treatment, but atrophy is common. The CSF is active when there is a meningoencephalitis, and oligoclonal bands do not occur. Treatment is with steroids and immunosuppression. Those with treatment resistant disease respond to biological agents, including TNF alpha, IL-1 and IL-6 antagonists.

Chronic signs of memory B cell activation in patients with Behçet's disease are partially restored by anti-tumour necrosis factor treatment

OBJECTIVES

Behçet's disease (BD), an auto-inflammatory vasculitis with oro-genital ulcerations, skin lesions and uveitis, is regarded as T cell mediated. A successful trial with rituximab suggests an additive role for B cells in the pathogenesis. Therefore, we studied B cell abnormalities in BD patients and the effect of TNF-blocking therapy.

METHODS

B cells in blood (n = 36) and tissue (n = 6) of BD patients were analysed with flow cytometry and/or immunohistochemistry and compared with healthy controls (n = 22). BD current activity form (BDCAF) in relation to B cell somatic hypermutations (SHMs) and immunoglobulin class-switching were studied.

RESULTS

Thirty-six patients (17 males) were included, mean age 44 years, average disease duration 10 years and mean BDCAF 2.7. Blood B cell numbers were significantly lower in patients than in controls (P = 0.0061), mostly due to decreased CD27⁺ memory B cells expressing IgM (P = 0.0001), IgG (P = 0.0002) and IgA (P = 0.0038) B cell subsets. CD27⁺ IgA⁺ B cells showed the highest magnitude of decrease in active disease, measured with BDCAF (P = 0.02). CD27⁺ IgM⁺ IgD⁺ B cells were impaired in replication history (P = 0.0133) and selection of SHM, whereas IgA⁺ B cells carried elevated SHM levels (P = 0.04) and lower IgA2 subclass usage (P = 0.0004) than controls. Immunohistochemistry revealed B cells in tissue of active mucosal ulcers. In adalimumab-treated patients, blood B cells were similar to controls.

CONCLUSION

We show significant deviations in the memory B cell compartment, related to disease activity and therapeutic efficacy. Pronounced molecular impairments were seen in the fast-responding IgM⁺-memory and the mucosal IgA⁺-memory B cells. Because of the demonstrated abundance of B cells in affected tissue, we hypothesize relocation of memory B cells to the site of inflammation could account for the deviations found in blood of BD patients. These peripheral B cells are easily accessible as a marker to monitor therapeutic efficacy.

TaqI, FokI, and ApaI Polymorphisms in the Vitamin D Receptor in Behçet's Disease in Turkish Population

Objectives. In our study we aimed to determine VDR gene polymorphisms in patients with Behçet's disease (BD) and neuro-Behçet's disease (NBD) in Turkish population. Methods. PBL obtained from 37 patients with BD, 21 patients with NB, and 30 healthy controls were investigated. Genomic DNA was extracted from whole blood using the QIAamp Blood Kit. VDR ApaI (rs7975232), VDR FokI (rs2228570), and VDR TaqI (rs731236) genotyping was performed by real-time polymerase chain reaction with SimpleProbe melting-curve analysis. Results. The allelic and genotype distributions of FokI and TaqI polymorphisms were not different among Behçet's disease, neuro-Behçet's disease, and control subjects in Turkish population (p > 0.05). Only the frequency of ApaI A allele in control is higher than that in BD (60% versus 38.5%), and the p value is 0.014, but the power is not enough to conclude that ApaI A allele is protective in BD in our study. Taken together, we found no significant differences between the BD, NBD, and control groups regarding the distribution of ApaI, TaqI, and FokI genotype and alleles frequencies. Conclusions. Future studies with larger patients' numbers may show differences between VDR polymorphisms and Behçet's disease.

A Case of Neuro-Behcet's Disease Presenting with Central Neurogenic Hyperventilation

Patient: Female, 46

Final Diagnosis: Central hyperventilation

Symptoms: Hyperventilation

Medication: —

Clinical Procedure: None

Specialty: Neurology

Pseudotumoral Behçet's disease

Behçet's disease is a systemic vasculitis characterized by the presence of oral and genital ulcers. Neurological involvement or neuro-Behçet is an uncommon manifestation. It manifestation has predominance in the male gender appearing 2 to 4 years after the first clinical manifestation. However, neuro-Behçet disease sometimes occurs with pseudotumoral brain lesions. Herein, we present the cases of two patients diagnosed with neuro-Behçet after detection of pseudotumoral brain lesions. A review of the literature is performed.

Behçet's disease physiopathology: a contemporary review

Behçet’s disease, also known as the Silk Road Disease, is a rare systemic vasculitis disorder of unknown etiology. Recurrent attacks of acute inflammation characterize Behçet’s disease. Frequent oral aphthous ulcers, genital ulcers, skin lesions and ocular lesions are the most common manifestations. Inflammation is typically self-limiting in time and relapsing episodes of clinical manifestations represent a hallmark of Behçet’s disease. Other less frequent yet severe manifestations that have a major prognostic impact involve the eyes, the central nervous system, the main large vessels and the gastrointestinal tract. Behçet’s disease has a heterogeneous onset and is associated with significant morbidity and premature mortality. This study presents a current immunological review of the disease and provides a synopsis of clinical aspects and treatment options.

[Neurological and psychiatric disorders in Behҫet's disease]

The data of the literature on epidemiology, clinical manifestations, diagnosis and treatment of Behcet's disease are presented. Particular attention is paid to international recommendations (2014) on the classification, diagnostic criteria and treatment of neurological symptoms of Behҫet disease.