Long-term remission, relapses and maintenance therapy in adult primary central nervous system vasculitis: A single-center 35-year experience

Cerebral Amyloid Angiopathy-Related Inflammation and Biopsy-Positive Primary Angiitis of the CNS: A Comparative Study

BACKGROUND AND OBJECTIVES

Cerebral amyloid angiopathy-related inflammation (CAA-RI) and biopsy-positive primary angiitis of the CNS (BP-PACNS) have overlapping clinicoradiologic presentations. It is unknown whether clinical and radiologic features can differentiate CAA-RI from BP-PACNS and whether both diseases have different relapse rates. The objectives of this study were to compare clinicoradiologic presentations and relapse rates in patients with CAA-RI vs BP-PACNS.

METHODS

Patients with CAA-RI and BP-PACNS were enrolled from 2 retrospective multicenter cohorts. Patients with CAA-RI were biopsy-positive or met probable clinicoradiologic criteria. Patients with BP-PACNS had histopathologic confirmation of CNS angiitis, with no secondary etiology. A neuroradiologist read brain MRIs, blinded to the diagnosis of CAA-RI or BP-PACNS. Clinicoradiologic features were compared using univariable logistic regression models. Relapse rates were compared using a univariable Fine-Gray subdistribution hazard model, with death as a competing risk.

RESULTS

This study enrolled 104 patients with CAA-RI (mean age 73 years, 48% female sex) and 52 patients with BP-PACNS (mean age 45 years, 48% female sex). Patients with CAA-RI more often had white matter hyperintense lesions meeting the probable CAA-RI criteria (93% vs 51%, p < 0.001), acute subarachnoid hemorrhage (15% vs 2%, p = 0.02), cortical superficial siderosis (27% vs 4%, p < 0.001), ≥1 lobar microbleed (94% vs 26%, p < 0.001), past intracerebral hemorrhage (17% vs 4%, p = 0.04), ≥21 visible centrum semiovale perivascular spaces (34% vs 4%, p < 0.01), and leptomeningeal enhancement (70% vs 27%, p < 0.001). Patients with BP-PACNS more often had headaches (56% vs 31%, p < 0.01), motor deficits (56% vs 36%, p = 0.02), and nonischemic parenchymal gadolinium enhancement (82% vs 16%, p < 0.001). The prevalence of acute ischemic lesions was 18% in CAA-RI and 22% in BP-PACNS (p = 0.57). The features with the highest specificity for CAA-RI were acute subarachnoid hemorrhage (98%), cortical superficial siderosis (96%), past intracerebral hemorrhage (96%), and ≥21 visible centrum semiovale perivascular spaces (96%). The probable CAA-RI criteria had a 71% sensitivity (95% CI 44%-90%) and 91% specificity (95% CI 79%-98%) in differentiating biopsy-positive CAA-RI from BP-PACNS. The rate of relapse in the first 2 years after remission was lower in CAA-RI than in BP-PACNS (hazard ratio 0.46, 95% CI 0.22-0.96, p = 0.04).

CONCLUSION

Clinicoradiologic features differed between patients with CAA-RI and those with BP-PACNS. Specific markers for CAA-RI were hemorrhagic signs of subarachnoid involvement, past intracerebral hemorrhage, ≥21 visible centrum semiovale perivascular spaces, and the probable CAA-RI criteria. A biopsy remains necessary for diagnosis in some cases of CAA-RI. The rate of relapse in the first 2 years after disease remission was lower in CAA-RI than in BP-PACNS.

Cortical Microhemorrhage Presentation of Small Vessel Primary Angiitis of the Central Nervous System

OBJECTIVE

Primary angiitis of the central nervous system (PACNS) is a rare vasculitis restricted to the brain, spinal cord, and leptomeninges. This study aimed to describe the imaging characteristics of patients with small vessel PACNS (SV-PACNS) using 7 T magnetic resonance imaging (MRI).

METHODS

This ongoing prospective observational cohort study included patients who met the Calabrese and Mallek criteria and underwent 7 T MRI scan. The MRI protocol includes T1-weighted magnetization-prepared rapid gradient echo imaging, T2 star weighted imaging, and susceptibility-weighted imaging. Two experienced readers independently reviewed the neuroimages. Clinical data were extracted from the electronic patient records. The findings were then applied to a cohort of patients with large vessel central nervous system (CNS) vasculitis.

RESULTS

We included 21 patients with SV-PACNS from December 2021 to November 2023. Of these, 12 (57.14%) had cerebral cortical microhemorrhages with atrophy. The pattern with microhemorrhages was described in detail based on the gradient echo sequence, leading to the identification of what we have termed the "coral-like sign." The onset age of patients with coral-like sign (33.83 ± 9.93 years) appeared younger than that of patients without coral-like sign (42.11 ± 14.18 years) (P = 0.131). Furthermore, the cerebral lesions in patients with cortical microhemorrhagic SV-PACNS showed greater propensity toward bilateral lesions (P = 0.03). The coral-like sign was not observed in patients with large vessel CNS vasculitis.

INTERPRETATION

The key characteristics of the coral-like sign represent cerebral cortical diffuse microhemorrhages with atrophy, which may be an important MRI pattern of SV-PACNS. ANN NEUROL 2024;96:194-203.

Primary Angiitis of the CNS: Differences in the Profile Between Subtypes and Outcomes From an Indian Cohort

BACKGROUND AND OBJECTIVES

Primary angiitis of the CNS (PACNS) is a rare disease that has significant morbidity and mortality. Subtypes of PACNS can have different presentations that could be missed with certain diagnostic modalities, further increasing diagnostic complexity. We sought to distinguish the subtypes of PACNS and describe their outcomes in an Indian cohort.

METHODS

Adult patients in this retrospective single-center cohort study were reviewed from the PACNS database between 2000 and 2019. Diagnosis was made as per Calabrese and Malleck criteria. Small and medium vessel vasculitis was defined, and their clinical and radiologic profile, treatment, and outcomes were compared. Functional outcomes were noted at 6-month, 1-year, and at last follow-up, while relapses were noted at last follow-up. A poor outcome was defined as modified Rankin Scale >2.

RESULTS

Seventy-two patients fulfilled the inclusion criteria of whom 50 (69.4%) were male. The small vessel vasculitis subtype had a younger age at onset (30.5 vs 40.5 years, p = 0.014), presented less often as a stroke (22% vs 62%, p = 0.001), and had greater delay in diagnosis and treatment initiation (median of 620 days vs 118 days, p = 0.001) compared with medium vessel vasculitis subtype. Although no difference was noted at 6 months, the small vessel vasculitis group had poor outcomes at 1-year and last follow-up (57% vs 20%, p = 0.011 and 72% vs 34%, p = 0.005, respectively) and had more relapses at last follow-up (89% vs 30%, p < 0.001) when compared with the medium vessel vasculitis group. On analyzing the entire cohort, 50 of 72 (69%) and 37 of 53 (69.8%) patients had a good outcome at 6 months and 1 year, respectively. Relapse was noted in 35 of 72 (49%) at final follow-up. The choice of the treatment regimen did not predict outcomes or relapses.

DISCUSSION

The small vessel vasculitis subtype of PACNS is a distinct entity that has diagnostic and treatment delays with poor long-term outcomes and more relapses. Recognizing the different subtypes of PACNS may help to expedite diagnosis and plan treatment.

Comparison of patients with biopsy positive and negative primary angiitis of the central nervous system

OBJECTIVE

There is limited evidence on when to obtain a central nervous system (CNS) biopsy in suspected primary angiitis of the central nervous system (PACNS). Our objective was to identify which clinical and radiological characteristics were associated with a positive biopsy in PACNS.

METHODS

From the multicentre retrospective Cohort of Patients with Primary Vasculitis of the CNS (COVAC), we included adults with PACNS based on a positive CNS biopsy or otherwise unexplained intracranial stenoses with additional findings supportive of vasculitis. Baseline findings were compared between patients with a positive and negative biopsy using logistic regression models.

RESULTS

Two hundred patients with PACNS were included, among which a biopsy was obtained in 100 (50%) and was positive in 61 (31%). Patients with a positive biopsy were more frequently female (odds ratio [OR] 2.90; 95% CI: 1.25, 7.10; P = 0.01) and more often presented with seizures (OR 8.31; 95% CI: 2.77, 33.04; P < 0.001) or cognitive impairment (OR 2.58; 95% CI: 1.11, 6.10; P = 0.03). On imaging, biopsy positive patients more often had non-ischaemic parenchymal or leptomeningeal gadolinium enhancement (OR 52.80; 95% CI: 15.72, 233.06; P < 0.001) or ≥1 cerebral microbleed (OR 8.08; 95% CI: 3.03, 25.13; P < 0.001), and less often had ≥1 acute brain infarct (OR 0.02; 95% CI: 0.004, 0.08; P < 0.001). In the multivariable model, non-ischaemic parenchymal or leptomeningeal gadolinium enhancement (adjusted OR 8.27; 95% CI: 1.78, 38.46; P < 0.01) and absence of ≥1 acute brain infarct (adjusted OR 0.13; 95% CI: 0.03, 0.65; P = 0.01) were significantly associated with a positive biopsy.

CONCLUSION

Baseline clinical and radiological characteristics differed between biopsy positive and negative PACNS. These results may help physicians individualize the decision to obtain a CNS biopsy in suspected PACNS.

Primary central nervous system vasculitis with intracranial aneurysm

BACKGROUND

Unruptured intracranial aneurysms (UIAs) are rarely reported in primary central nervous system vasculitis (PCNSV). In this study we described the clinical findings, response to therapy, and outcomes of UIA in a large cohort of PCNSV patients.

METHODS

We retrospectively studied 216 consecutive patients with PCNSV, selected by predetermined diagnostic criteria, who were seen during a 40-year period. UIAs were identified on cerebral angiography. The clinical, laboratory, radiologic and pathologic findings, management, and outcomes of patients with UIA were described and compared with those without UIA.

RESULTS

12/216 (5.5 %) PCNSV patients had at least one UIA. Two patients underwent biopsies; one yielded negative results, while the other showed necrotizing vasculitis. Eleven patients had evidence of UIA on angiogram at diagnosis. One patient developed an aneurysm during the follow-up associated with a worsening of vasculitic radiological findings. The most common presenting symptom for PCNSV in the setting of UIA was headache (67 %), followed by persistent neurologic deficit or stroke (50 %). Most patients with UIA presented with multiple cerebral infarcts on MRI (67 %), one patient had subarachnoid hemorrhage, and one left parieto-occipital intracerebral hematoma, both unrelated to the aneurysm. Black blood imaging was performed in 4 patients and 2 showed segmental circumferential mural enhancement involving multiple vessels. Two patients had 2 UIAs, while the other 10 had 1. The most frequent UIA location was internal carotid artery (50 %), followed by anterior cerebral artery (21 %). Ten of the UIAs were < 5 mm in diameter, and 3 were 5-7 mm in diameter; the size was not available for one. All UIAs were unchanged in size and configuration during follow-up (median: 18.5 months; range 1-151 months) and no new aneurysms were detected. Compared to the 204 patients with PCNSV without a UIA, no significant clinical differences were observed, except for a reduced disability at last follow-up (p = 0.038).

CONCLUSIONS

UIAs uncommonly occur in PCNSV.

Headaches and Vasculitis

Vasculitis refers to heterogeneous clinicopathologic disorders that share the histopathology of inflammation of blood vessels. Unrecognized and therefore untreated, vasculitis of the nervous system leads to pervasive injury and disability making this a disorder of paramount importance to all clinicians. Headache may be an important clue to vasculitic involvement of central nervous system (CNS) vessels. CNS vasculitis may be primary, in which only intracranial vessels are involved in the inflammatory process, or secondary to another known disorder with overlapping systemic involvement. Primary neurologic vasculitides can be diagnosed with assurance after intensive evaluation that incudes tissue confirmation whenever possible.

Vasculitis in the Central Nervous System: Etiology, Characteristics, and Outcomes in a Large Single-Center Cohort

Background and Purpose

For the management of central nervous system (CNS) vasculitis, it is crucial to differentiate between primary and secondary CNS vasculitis and to understand the respective etiologies. We assessed the etiology, characteristics, and outcomes of patients with CNS vasculitis.

Methods

A single-center retrospective chart review was conducted at the University of Utah, Department of Neurology, between February 2011 and October 2022.

Results

The median age of the 44 included patients at diagnosis was 54 years; 25.0% were men. Compared to primary CNS vasculitis, secondary CNS vasculitis exhibits higher fever incidence (observed in infectious and connective tissue disorder [CTD]-associated vasculitis), low glucose levels (mostly in infectious vasculitis) and unique cerebrospinal fluid oligoclonal bands (observed in infectious and CTD-associated vasculitis). Patients with inflammatory cerebral amyloid angiopathy (CAA) were older and more commonly had microhemorrhage than primary angiitis of the CNS (PACNS). All patients with CTD-associated vasculitis had a known history of CTD at presentation. Brain biopsies were performed on 10 of 17 PACNS patients and 4 of 8 inflammatory CAA patients, confirming vasculitis in 7 and 4 patients, respectively. Intravenous methylprednisolone was the predominant induction therapy (63.6%), and cyclophosphamide was the most used adjunctive therapy. Cyclophosphamide, rituximab, azathioprine, and mycophenolate mofetil were utilized as maintenance therapy, often with concurrent prednisone. Patients with inflammatory CAA had a higher tendency for relapse rates than PACNS.

Conclusions

This study highlights the variations in patients' characteristics, symptoms, and treatment for CNS vasculitis. Understanding these differences can lead to more efficient diagnostic and management strategies.

Primary angiitis of the central nervous system

Primary angiitis of the central nervous system (CNS) is an uncommon inflammatory disorder, with highly variable clinical presentation. It needs to be differentiated from several mimickers, such as CNS involvement in systemic vasculitides, connective tissue disorders, infectious disease, and leukodystrophy as well as neoplastic diseases. The diagnosis requires a combination of clinical and laboratory investigations, multimodal imaging, and histopathological examination, which should be available for confirmation. In the present paper, the histopathological features of primary angiitis of the CNS are described and highlighted to help pathologists avoid misdiagnosis of a treatable acquired disease.

The Hemorrhagic Side of Primary Angiitis of the Central Nervous System (PACNS)

Primary Angiitis of the Central Nervous System (PACNS) is a rare cerebrovascular disease involving the arteries of the leptomeninges, brain and spinal cord. Its diagnosis can be challenging, and the current diagnostic criteria show several limitations. Among the clinical and neuroimaging manifestations of PACNS, intracranial bleeding, particularly intracerebral hemorrhage (ICH), is poorly described in the available literature, and it is considered infrequent. This review aims to summarize the available data addressing this issue with a dedicated focus on the clinical, neuroradiological and neuropathological perspectives. Moreover, the limitations of the actual data and the unanswered questions about hemorrhagic PACNS are addressed from a double point of view (PACNS subtyping and ICH etiology). Fewer than 20% of patients diagnosed as PACNS had an ICH during the course of the disease, and in cases where ICH was reported, it usually did not occur at presentation. As trigger factors, both sympathomimetic drugs and illicit drugs have been proposed, under the hypothesis of an inflammatory response due to vasoconstriction in the distal cerebral arteries. Most neuroradiological descriptions documented a lobar location, and both the large-vessel PACNS (LV-PACNS) and small-vessel PACNS (SV-PACNS) subtypes might be the underlying associated phenotypes. Surprisingly, amyloid beta deposition was not associated with ICH when histopathology was available. Moreover, PACNS is not explicitly included in the etiological classification of spontaneous ICH. This issue has received little attention in the past, and it could be addressed in future prospective studies.

Treatment of Primary Angiitis of the Central Nervous System

Primary central nervous system vasculitis (PCNSV) is a vasculitis limited to the brain and spinal cord. Induction therapy often consists of steroids and cyclophosphamide. Maintenance therapy includes a prednisone taper and may be combined with medications such as azathioprine or mycophenolate mofetil. Relapse is common in PCNSV and an increased dose of steroids is often given, sometimes with a change in therapy. Medications such as rituximab and mycophenolate mofetil may be good alternatives in those who do not respond to initial treatment or who have relapse of disease. Mortality rates of 8% to 9% are reported in the literature.

European Stroke Organisation (ESO) guidelines on Primary Angiitis of the Central Nervous System (PACNS)

The European Stroke Organisation (ESO) guideline on Primary Angiitis of the Central Nervous System (PACNS), developed according to ESO standard operating procedures (SOP) and Grading of Recommendations, Assessment, Development and Evaluation (GRADE) methodology, was elaborated to assist clinicians in the diagnostic and treatment pathway of patients with PACNS in their decision making. A working group involving vascular neurologists, neuroradiologists, rheumatologists, a neuropathologist and a methodologist identified 17 relevant clinical questions; these were addressed according to the patient/population, intervention, comparison and outcomes (PICO) framework and systematic literature reviews were performed. Notably, each PICO was addressed with respect to large vessel (LV)-PACNS and small vessel (SV)-PACNS. Data to answer many questions were scarce or lacking and the quality of evidence was very low overall, so, for some PICOs, the recommendations reflect the ongoing uncertainty. When the absence of sufficient evidence precluded recommendations, Expert Consensus Statements were formulated. In some cases, this applied to interventions in the diagnosis and treatment of PACNS which are embedded widely in clinical practice, for example patterns of cerebrospinal fluid (CSF) and Magnetic Resonance Imaging (MRI) abnormalities. CSF analysis for hyperproteinorrachia and pleocytosis does not have evidence supporting their use as diagnostic tools. The working group recommended that caution is employed in the interpretation of non-invasive vascular imaging due to lack of validation and the different sensitivities in comparison with digital subtraction angiography (DSA) and histopathological analyses. Moreover, there is not a neuroimaging pattern specific for PACNS and neurovascular issues are largely underreported in PACNS patients. The group's recommendations on induction and maintenance of treatment and for primary or secondary prevention of vascular events also reflect uncertainty due to lack of evidence. Being uncertain the role and practical usefulness of current diagnostic criteria and being not comparable the main treatment strategies, it is suggested to have a multidisciplinary team approach in an expert center during both work up and management of patients with suspected PACNS. Highlighting the limitations of the currently accepted diagnostic criteria, we hope to facilitate the design of multicenter, prospective clinical studies and trials. A standardization of neuroimaging techniques and reporting to improve the level of evidence underpinning interventions employed in the diagnosis and management of PACNS. We anticipate that this guideline, the first comprehensive European guideline on PACNS management using GRADE methodology, will assist clinicians to choose the most effective management strategy for PACNS.

Primary Angiitis of the Central Nervous System in Adults: A Comprehensive Review of 76 Biopsy-Proven Case Reports

Purpose

Primary angiitis of the adult central nervous system (PACNS) is an increasingly recognized but limited disease. Using previous case reports, we sought to summarize the clinical symptoms, imaging manifestations, treatment, and prognosis of patients with biopsy-confirmed PACNS to guide clinical diagnosis and management.

Methods

We searched the Web of Science database for studies published from January 2000 to April 2023, with the language set to English and the document type limited to [Article or Review or Letter or Editorial Material]. A systematic review of all case reports met the inclusion and exclusion criteria was performed. These patients' clinical, pathological, and imaging characteristics were analyzed, and treatment and prognostic data were summarized.

Results

We analyzed 69 articles, including 76 patients with biopsy-confirmed PACNS. And 57.9% of the patients were male, the median age at presentation was 47.0 years, and focal neurological deficits were the most common symptom in patients (78.9%), followed by headache (52.6%). The median duration of biopsy was 1.1 months, of which 49 (64.5%) patients were lymphocytic, 13 (17.1%) were granulomatous, 11 (14.5%) were amyloidotic, and 3 (3.9%) were necrotizing PACNS. Relapse events occurred in 41 (53.9%) patients, including 34 (44.2%) relapses and 8 (10.5%) deaths. Univariate logistic regression analysis revealed that symptomatic epilepsy, prolonged biopsy time window, and CD20 expression in pathological tissues might be independent risk factors for recurrent events in patients (HR=4.69, 95% CI: 1.51-14.54, p=0.007; HR=1.11, 95% CI: 1.00-1.22, p=0.043; HR=5.33, 95% CI: 1.07-26.61, p=0.041).

Conclusion

Adult PACNS is associated with frequent relapses and high mortality. Symptomatic epilepsy, prolonged biopsy time window, and CD20 expression in pathological tissue may be associated with recurrent events.

Unilateral Relapsing Primary CNS Vasculitis: Description of 3 Cases From a Single-Institutional Cohort of 216 Cases

OBJECTIVES

To define the frequency and characteristics of patients with unilateral relapsing involvement in a cohort of patients with adult primary CNS vasculitis (PCNSV).

METHODS

We retrospectively studied a cohort of 216 patients with PCNSV seen at the Mayo Clinic, Rochester, MN from 1983 to 2022. Twenty-five patients (19.8%) had at least 2 flares. Three of them (1.4%) had unilateral relapsing vasculitis. We described these 3 patients and compared them with the entire cohort of 216 patients.

RESULTS

All 3 patients had angiography-negative and biopsy-positive PCNSV with granulomatous-necrotizing and lymphocytic vasculitides and amyloid beta-related angiitis. The main manifestation at diagnosis and during flares was seizures. Unilateral lesions with gadolinium enhancement were the main MRI finding. Spinal fluid examination at diagnosis was normal in 2 patients. All had multiple flares (from 4 to 10) and were treated with long-term high-dose prednisone and numerous traditional immunodepressive drugs, and one received rituximab for steroid resistance. All 3 patients had slight disability with mild cognitive impairment at last follow-up.

DISCUSSION

Unilateral relapsing involvement represents a rare subset of PCNSV with peculiar characteristics and can be observed in all neuropathologic patterns.

Central Nervous System Vasculitis: Primary Angiitis of the Central Nervous System and Central Nervous System Manifestations of Systemic Vasculitis

Central nervous system vasculitis (CNSV) is a group of disorders leading to inflammatory vasculopathy within the brain, spinal cord, and leptomeninges. CNSV is divided into primary angiitis of the central nervous system (PACNS) and secondary CNSV based on the underlying etiology. PACNS is a rare inflammatory disorder with poorly understood pathophysiology and heterogeneous and highly variable clinical features. The diagnosis depends on a combination of clinical and laboratory variables, multimodal imaging, and histopathological examination as well as exclusion of mimics. Several systemic vasculitides, infectious etiologies and connective tissue disorders have been shown to cause secondary CNSV and require prompt recognition.

Mycophenolate mofetil as induction and maintenance immunosuppressive therapy in adult primary central nervous system vasculitis: A prospective observational study

To observe the clinical and angiographic effectiveness of mycophenolate mofetil (MMF) as induction and maintenance immunosuppressive therapy in primary central nervous system vasculitis (PCNSV). In this open-label prospective study done at a tertiary care neurology centre, adult patients with PCNSV, diagnosed by Calabrese's criteria, were recruited from 2017 to 2021 and treated with glucocorticoids, MMF and standard of care. Patients were followed-up and clinical and angiographic changes were recorded. Total 26 patients were recruited with median age 39 years (34-49) with a slight female predilection (61.5%). Angiographic diagnoses were: small vessels disease 11.5%; large vessels disease 42.3% and both in 46.2%. Median duration of follow-up was 24.5 months (14.25-38). Proportion of patients with severe disability (modified Rankin Score (mRS) 4-6) at baseline was 73.08% (19/26) which reduced to 7.69% (2/26) (p < 0.001). At the last follow-up mRS = 0 was achieved in 38.5% (10/26) and mRS of ≤ 1 was achieved in 69.2% (18/26). Median time to achieve a mRS ≤ 1 was 12 months (95% CI: 6.8-17.2). Angiography was repeated in 16 patients after a median duration of 13 months (10.5-19.7), out of which 10 (62.5%) showed improvement and 5 (31.2%) showed non-progression of lesions. MMF may be an effective immunosuppressive therapy in adult PCNSV as both induction and maintenance. Serial DSA of brain may be useful to monitor the effect of treatment. Key Points • Mycophenolate mofetil is effective as induction and maintenance immunosuppressive therapy in PCNSV. • Repeat angiogram may be useful to monitor treatment response in PCNSV.

Diagnosis and management of adult primary angiitis of the central nervous system: an international survey on current practices

BACKGROUND

Primary angiitis of the central nervous system (PACNS) is a rare disease, for which no validated guidelines exist. We report the findings of a survey on the clinical practice of physicians who manage adults with PACNS.

METHODS

An online survey was distributed through neurology, internal medicine, and rheumatology societies in Canada and Europe. Participants who were directly involved as treating physicians for at least two adult patients with PACNS were eligible for the survey.

RESULTS

Ninety-six physicians completed the survey. Most participants were neurologists (n = 38, 40%), internists (n = 34, 35%) or rheumatologists (n = 22, 23%). Participants obtained a CNS biopsy in a median of 25% (IQR: 5-50%) of suspected PACNS cases. When determining the degree to which eight scenarios justified a CNS biopsy, participants achieved fair inter-rater agreement (Gwet's AC₂ 0.30, 95% CI 0.23-0.41). For induction therapy, 81 (84%) participants reported using glucocorticoids and cyclophosphamide in > 50% of patients. After obtaining remission, 85 (89%) participants systematically introduced or maintained immunosuppressive therapy. Glucocorticoids were prescribed for a median of 12 months. Maintenance therapy with another immunosuppressant was continued for a median of 24 months. In patients who achieved remission, we explored how eight scenarios with different imaging and CSF results supported an increase in treatment. Inter-rater agreement was substantial if the patient was symptomatic (0.66, 95% CI 0.58-0.80) and moderate (0.50, 95% CI 0.45-0.60) if asymptomatic.

CONCLUSION

This survey illustrates current real-world management of PACNS and emphasizes several areas for which physicians still lack study-based evidence and/or clinical practice guidelines.

Exploring Gene Expression Profiles in Primary Central Nervous System Vasculitis

OBJECTIVE

This study was undertaken to explore the gene expression profile of primary central nervous system vasculitis (PCNSV).

METHODS

Brain specimens of 4 patients with granulomatous vasculitis (GV), 5 with lymphocytic vasculitis (LV), 4 with amyloid β-related angiitis (ABRA), and 4 normal controls were studied. RNA-sequencing was performed using the Illumina Hiseq-4,000 platform and the Illumina TruSeq Total-RNA library. Student t test and false discovery rate tests were performed for each of the differentially expressed transcripts. Ingenuity Pathway Analysis was used for the pathway expression analysis. CIBERSORT was used to estimate the abundances of different immune cell subsets in the tissues based on gene expression data.

RESULTS

Transcripts differentially expressed between PCNSV and normal brain indicated that endosomal, mitochondrial, and ribosome dysfunction, alterations in protein synthesis, and noncoding RNAs might be involved in PCNSV. Pathway analysis revealed the activation of dendritic cell maturation and antigen processing as well as neuroinflammation in PCNSV versus normal brain, whereas oxidative phosphorylation was inhibited. CIBERSORT estimation of immune cell subsets suggested that activated NK cells, M1 macrophages, memory B cells, and follicular helper T cells were likely to be more prevalent in PCNSV samples. Naïve CD4 T cells and monocytes were mainly estimated to be present in GV and ABRA. Plasma cell and γδ T-cell signatures were mainly found in LV and normal brain. GV showed higher levels of genes associated with macrophage activities and T cells. ABRA showed higher levels of long noncoding RNAs and miR-616. LV showed higher levels of genes encoding immunoglobulins.

INTERPRETATION

RNA sequencing confirmed PCNSV heterogeneity. ANN NEUROL 2023;93:120-130.

Adult and childhood vasculitis

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

Diagnostic and therapeutic approach to adult central nervous system vasculitis

The clinical manifestations of central nervous system (CNS) vasculitis are highly variable. In the absence of a positive CNS biopsy, CNS vasculitis is particularly suspected when markers of both vascular disease and inflammation are present. To facilitate the clinical and therapeutic approach to this rare condition, CNS vasculitis can be classified according to the size of the involved vessels. Vascular imaging is used to identify medium vessel disease. Small vessel disease can only be diagnosed with a CNS biopsy. Medium vessel vasculitis usually presents with focal neurological signs, while small vessel vasculitis more often leads to cognitive deficits, altered level of consciousness and seizures. Markers of CNS inflammation include cerebrospinal fluid pleocytosis or elevated protein levels, and vessel wall, parenchymal or leptomeningeal enhancement. The broad range of differential diagnoses of CNS vasculitis can be narrowed based on the disease subtype. Common mimickers of medium vessel vasculitis include intracranial atherosclerosis and reversible cerebral vasoconstriction syndrome. The diagnostic workup aims to answer two questions: is the neurological presentation secondary to a vasculitic process, and if so, is the vasculitis primary (i.e., primary angiitis of the CNS) or secondary (e.g., to a systemic vasculitis, connective tissue disorder, infection, malignancy or drug use)? In primary angiitis of the CNS, glucocorticoids and cyclophosphamide are most often used for induction therapy, but rituximab may be an alternative. Based on the available evidence, all patients should receive maintenance immunosuppression. A multidisciplinary approach is necessary to ensure an accurate and timely diagnosis and to improve outcomes for patients with this potentially devastating condition.

Vessel wall magnetic resonance and arterial spin labelling imaging in the management of presumed inflammatory intracranial arterial vasculopathy

Optimal criteria for diagnosing and monitoring response to treatment for infectious and inflammatory medium–large vessel intracranial vasculitis presenting with stroke are lacking. We integrated intracranial vessel wall MRI with arterial spin labelling into our routine clinical stroke pathway to detect presumed inflammatory intracranial arterial vasculopathy, and monitor disease activity, in patients with clinical stroke syndromes. We used predefined standardized radiological criteria to define vessel wall enhancement, and all imaging findings were rated blinded to clinical details. Between 2017 and 2018, stroke or transient ischaemic attack patients were first screened in our vascular radiology meeting and followed up in a dedicated specialist stroke clinic if a diagnosis of medium–large inflammatory intracranial arterial vasculopathy was radiologically confirmed. Treatment was determined and monitored by a multi-disciplinary team. In this case series, 11 patients were managed in this period from the cohort of young stroke presenters (<55 years). The median age was 36 years (interquartile range: 33,50), of which 8 of 11 (73%) were female. Two of 11 (18%) had herpes virus infection confirmed by viral nucleic acid in the cerebrospinal fluid. We showed improvement in cerebral perfusion at 1 year using an arterial spin labelling sequence in patients taking immunosuppressive therapy for >4 weeks compared with those not receiving therapy [6 (100%) versus 2 (40%) P = 0.026]. Our findings demonstrate the potential utility of vessel wall magnetic resonance with arterial spin labelling imaging in detecting and monitoring medium–large inflammatory intracranial arterial vasculopathy activity for patients presenting with stroke symptoms, limiting the need to progress to brain biopsy. Further systematic studies in unselected populations of stroke patients are needed to confirm our findings and establish the prevalence of medium–large artery wall inflammation.

Primary Central Nervous System Angiitis Mimicking a Space-Occupying Lesion

Background and Purpose Intracranial space-occupying lesions are a sine qua non for neoplastic lesions; however, occasionally non-neoplastic lesions mimic neoplastic lesions, leading to diagnostic dilemmas. We report our experience with three patients who presented with a progressive hemispheric syndrome and the diagnostic considerations involved in the cases.

Materials and Methods In this retrospective study, we included three patients with primary angiitis of central nervous system (PACNS) who underwent craniotomy and biopsy, suspecting it to be mass lesions. Demographic features, clinical features, radiological features, histopathology, treatment, and clinical outcomes were studied.

Results Majority were males. The male:female ratio was 2:1. Lobar involvement was common. MR brain with contrast showed features of high-grade glioma. Despite hemispheric involvement, there was no mass effect. Perilesional edema was seen in all cases. All underwent craniotomy and biopsy; histopathology was consistent with PACNS. All patients were treated with corticosteroids and cyclophosphamide. Rituximab was used in addition to cyclophosphamide in one patient. At 2 years follow-up, two patients were in disease remission and one patient died due to disease progression.

Conclusion PACNS has a protean clinical manifestation. A high index of suspicion is required in cases with atypical clinical presentations, radiological features, and normal angiograms. Early histological diagnosis and aggressive immunotherapy with high-dose corticosteroids combined with intravenous cyclophosphamide yields favorable outcomes.

Primary Angiitis of the CNS: A Systematic Review and Meta-analysis

BACKGROUND AND OBJECTIVES

To facilitate and improve the diagnostic and therapeutic process by systematically reviewing studies on patients with primary angiitis of the CNS (PACNS).

METHODS

We searched PubMed, looking at the period between 1988 and February 2020. Studies with adult patients with PACNS were included. We extracted and pooled proportions using fixed-effects models. Main outcomes were proportions of patients with certain clinical, imaging, and laboratory characteristics and neurologic outcomes.

RESULTS

We identified 46 cohort studies including a total of 911 patients (41% biopsy confirmed, 43% angiogram confirmed, and 16% without clear assignment to the diagnostic procedure). The most frequent onset symptoms were focal neurologic signs (63%), headache (51%), and cognitive impairment (41%). Biopsy- compared with angiogram-confirmed cases had higher occurrences of cognitive impairment (55% vs 39%) and seizures (36% vs 16%), whereas focal neurologic signs occurred less often (56% vs 95%). CSF abnormalities were present in 75% vs 65% and MRI abnormalities in 97% vs 98% of patients. Digital subtraction angiography was positive in 33% of biopsy confirmed, and biopsy was positive in 8% of angiogram-confirmed cases. In 2 large cohorts, mortality was 23% and 8%, and the relapse rate was 30% and 34%, during a median follow-up of 19 and 57 months, respectively. There are no randomized trials on the treatment of PACNS. The initial treatment usually includes glucocorticoids and cyclophosphamide.

DISCUSSION

PACNS is associated with disabling symptoms, frequent relapses, and significant mortality. Differences in symptoms and neuroimaging results and low overlap between biopsy and angiogram suggest that biopsy- and angiogram-confirmed cases represent different histopathologic types of PACNS. The optimal treatment is unknown.

Diagnosis and follow-up evaluation of central nervous system vasculitis: an evaluation of vessel-wall MRI findings

Objective

To approach the clinical value of MRI with vessel wall imaging (VWI) in patients with central nervous system vasculitis (CNSV), we analyzed patterns of VWI findings both at the time of initial presentation and during follow-up.

Methods

Stenoocclusive lesions, vessel-wall contrast enhancement (VW-CE) and diffusion-restricted lesions were analyzed in patients with a diagnosis of CNSV. On available VWI follow-up, progression, regression or stability of VW-CE were evaluated and correlated with the clinical status.

Results

Of the 45 patients included, 28 exhibited stenoses visible on MR angiography (MRA-positive) while 17 had no stenosis (MRA-negative). VW-CE was found in 2/17 MRA-negative and all MRA-positive patients (p < 0.05). 79.1% (53/67) of stenoses showed VW-CE. VW-CE was concentric in 88.3% and eccentric in 11.7% of cases. Diffusion-restricted lesions were found more frequently in relation to stenoses with VW-CE than without VW-CE (p < 0.05). 48 VW-CE lesions in 23 patients were followed over a median time of 239.5 days. 13 VW-CE lesions (27.1%) resolved completely, 14 (29.2%) showed partial regression, 17 (35.4%) remained stable and 4 (8.3%) progressed. 22/23 patients received immunosuppressive therapy for the duration of follow-up. Patients with stable or progressive VW-CE were more likely (p < 0.05) to have a relapse (14/30 cases) than patients with partial or complete regression of VW-CE (5/25 cases).

Conclusion

Concentric VW-CE is a common finding in medium/large-sized vessel CNSV. VW-CE might represent active inflammation in certain situations. However, follow-up VWI findings proved ambiguous as persisting VW-CE despite immunosuppressive therapy and clinical remission was a frequent finding.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00415-021-10683-7.

Cryptococcus meningitis mimicking cerebral septic emboli, a case report series demonstrating injection drug use as a risk factor for development of disseminated disease

Background

Clinicians may be less inclined to consider a diagnosis of cryptococcal meningitis in people without HIV infection or transplant-related immunosuppression. This may lead to a delay in diagnosis particularly if disseminated cryptococcal disease mimics cerebral septic emboli in injection drug use (IDU) leading to a search for endocarditis or other infectious sources. Though, IDU has been described as a potential risk for disseminated cryptococcal disease.

Case presentations

We present two cases of cryptococcal meningitis in IDU without HIV or other obvious immune deficits. Both patients presented with at least 2 weeks of headache and blurred vision. They developed central nervous system (CNS) vasculitis, one of which mimicked septic cerebral emboli, but both resulted with poor neurologic outcomes.

Conclusions

IDU likely induces an underappreciated immune deficit and is a risk factor for developing cryptococcal meningitis. This diagnosis, which can mimic cerebral septic emboli through involvement of a CNS vasculitis, should be considered in the setting of IDU.