Profiling Complement System Components in Primary CNS Vasculitis.

Complement activation has been implicated in the pathogenesis of many vasculitic syndromes such as anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitides. Using an array-based multiplex system, we simultaneously quantified serum and CSF levels of activated and regulatory complement system proteins in patients with primary CNS vasculitis (PACNS; n = 20) compared to patients with non-inflammatory conditions (n = 16). Compared to non-inflammatory controls, levels of C3a, C5a, and SC5b-9, indicative for general activation of the complement system, of C4a, specific for the activation of the classical pathway, Ba and Bb, reflective for alternative complement activation as well as concentrations of complement-inhibitory proteins factor H and factor I were unchanged in patients with PACNS. Our study does not support the hypothesis that complement activation is systemically increased in patients with PACNS.

Unilateral Relapsing Primary Angiitis of the CNS: An Entity Suggesting Differences in the Immune Response Between the Cerebral Hemispheres.

OBJECTIVE: To determine whether studying patients with strictly unilateral relapsing primary angiitis of the CNS (UR-PACNS) can support hemispheric differences in immune response mechanisms, we reviewed characteristics of a group of such patients. METHODS: We surveiled our institution for patients with UR-PACNS, after characterizing one such case. We defined UR-PACNS as PACNS with clinical and radiographic relapses strictly recurring in 1 brain hemisphere, with or without hemiatrophy. PACNS must have been biopsy proven. Three total cases were identified at our institution. A literature search for similar reports yielded 4 additional cases. The combined 7 cases were reviewed for demographic, clinical, imaging, and pathologic trends. RESULTS: The median age at time of clinical onset among the 7 cases was 26 years (range 10-49 years); 5 were male (71%). All 7 patients presented with seizures. The mean follow-up duration was 7.5 years (4-14.1 years). The annualized relapse rate ranged between 0.2 and 1. UR-PACNS involved the left cerebral hemisphere in 5 of the 7 patients. There was no consistent relationship between the patient's dominant hand and the diseased side. When performed (5 cases), conventional angiogram was nondiagnostic. CSF examination showed nucleated cells and protein levels in normal range in 3 cases and ranged from 6 to 11 cells/µL and 49 to 110 mg/dL in 4 cases, respectively. All cases were diagnosed with lesional biopsy, showing lymphocytic type of vasculitis of the small- and medium-sized vessels. Patients treated with steroids alone showed progression. Induction therapy with cyclophosphamide or rituximab followed by a steroid sparing agent resulted in the most consistent disease remission. CONCLUSIONS: Combining our 3 cases with others reported in the literature allows better clinical understanding about this rare and extremely puzzling disease entity. We hypothesize that a functional difference in immune responses, caused by such discrepancies as basal levels of cytokines, asymmetric distribution of microglia, and differences in modulation of the systemic immune functions, rather than a structural antigenic difference, between the right and left brain may explain this phenomenon, but this is speculative.

IVIG in childhood primary angiitis of the central nervous system: A case report.

Aggressive immunosuppressive therapies have been proposed to treat primary angiitis of the central nervous system (PACNS). Here, we report the first successfully stabilized case of childhood, small-vessel PACNS with intravenous immunoglobulin (IVIG) therapy. A 12-year-old boy was admitted to our hospital complaining of recurrent headaches and upper-left homonymous quadrantanopia, since the age of 11 years. Brain computed tomography scans revealed fine calcification in the right temporal and occipital lobes. Brain magnetic resonance imaging scans revealed white matter lesions, with gadolinium enhancement, which waxed, waned, and migrated for 1 year, without immunomodulatory therapies. A cerebrospinal fluid study showed pleocytosis (12 cells per µl). No clinical or serological findings suggested systemic inflammation or vasculitis. Brain angiography was unremarkable. Brain biopsy revealed thickened and hyalinized small vessels, with intramural infiltration of inflammatory cells, which confirmed the diagnosis of small-vessel PACNS. Because the patient developed surgical site infection following biopsy, the administration of monthly IVIG (2 g/kg) was prescribed, instead of immunosuppressive agents. After IVIG therapy, the patient remained stable, except for a single episode of mild radiological exacerbation at 16 months, which occurred when the IVIG interval was expanded. Oral prednisone was added and gradually tapered. At 50 months, his intellectual abilities and motor functions were normal, although he showed residual upper-left homonymous quadrantanopia and post-exercise headache. A temporary headache, associated with the immunoglobulin infusion, was resolved by slowing the infusion rate. PACNS should be treated aggressively to improve prognosis. However, when immunosuppressants are contraindicated, IVIG may be an alternative therapeutic option.

Certified reference material against PR3 ANCA IgG autoantibodies. From development to certification.

Background The importance of the standardisation of immunoassays for autoantibodies has been widely discussed. The appropriate use of certified reference materials (CRM) could contribute to a more accurate diagnosis and follow-up of a series of diseases such as small vessel-associated vasculitis. This is a systemic autoimmune disorder during which two autoantibodies can be present, MPO ANCA IgG and PR3 ANCA IgG. Results from different commercially available immunoassays used for PR3 ANCA IgG measurement can vary significantly. Therefore the potential for improvement using a suitable certified reference material was assessed and led to the development of a CRM. Methods Thirty clinical samples were evaluated using 10 immunoassays. The correlation between results from these assays was assessed in a pairwise manner. Feasibility studies were conducted in order to find a reference material format most suitable for the preparation of a CRM. Results The evaluation of two sets of 30 clinical samples with 10 assays showed that differences between assays can result in different interpretations for individual clinical samples. Most of the samples had the same result classification in all assays. However, six of the samples tested led to inconsistent results. Conclusions The correlation between results from clinical samples was systematically good for combinations of eight of those assays. Therefore, it should be possible to improve the comparability of results using a commutable CRM for calibration. Based on these studies, a final format for the CRM was selected and eventually produced and certified for its PR3 ANCA IgG content.

Rituximab therapy for primary central nervous system vasculitis: A 6 patient experience and review of the literature.

OBJECTIVES: To assess the efficacy and safety of Rituximab (RTX) in adult primary central nervous system vasculitis (PCNSV). METHODS: We retrospectively assessed the effect of RTX in 6 patients with PCNSV. Five of the 6 were refractory to high dose glucocorticoids (GCs) and/or conventional immunosuppressants (IS). The sixth was newly diagnosed and received RTX in combination with GCs. Clinical evaluation, laboratory tests, and imaging modalities were performed at initial RTX administration and during the follow-up. Treatment response was assessed using the treating physician's global opinion regarding response and the degree of disability using the modified Rankin scale (mRS). We also performed a literature review for previous use of RTX in PCNSV using PubMed, Ovid Medline, and the Cochrane library. RESULTS: The six patients (3 females) had a median age at diagnosis of 50.5 years (range 17-68 years). All had active disease when RTX was started. In 4 patients, RTX administration was associated with a marked reduction in the number of flares (from 18 before starting RTX to 3 after). One patient, after an initial improvement, had 2 flares when B cells were depleted and he was not able to reduce prednisone below 20 mg/day. A 6th patient had a flare when B cells recovered and retreatment with RTX re-induced and maintained remission. The median mRS score at last visit (median: 2; range 0-4) was lower than that prior to treatment (median 3; range 1-5). The median prednisone daily dose before RTX administration was significantly higher than that at last follow-up (p = .006). In the literature review, we identified 5 papers describing 7 patients treated with RTX. Six patients responded to RTX with clinical and MRI improvement with no reported flares after RTX treatment. CONCLUSIONS: Our data support a potential role for RTX treatment in selected patients with PCNSV.

Extracranial-Intracranial Bypass for Cerebral Vasculitis After Graft-Versus-Host Disease: Case Report and Review of the Literature.

BACKGROUND: Cerebral vasculitis owing to chronic graft-versus-host disease (GVHD) is very rare. To our knowledge, only 2 cases have been reported. We describe the first case of superficial temporal artery-middle cerebral artery (STA-MCA) bypass for cerebral vasculitis owing to GVHD. CASE DESCRIPTION: A 59-year-old woman presented with right upper extremity weakness and dysarthria 33 months after undergoing matching allogenic bone marrow transplantation. The patient had STA-MCA bypass for MCA occlusion and resting cerebral blood flow in the left MCA area improved. CONCLUSIONS: Although the mechanism of cerebral vasculitis after chronic GVHD is not known, cerebral vasculitis that causes cerebrovascular disease long after bone marrow transplantation should be considered. In this case, an STA-MCA bypass was efficient for the repeated ischemic attacks owing to cerebral vasculitis. Moreover, it is important to select the optimal recipient vessels to area originated neurologic symptoms.

Anti-neutrophil cytoplasmic antibody associated central nervous system vasculitis with brain and spinal cord subarachnoid hemorrhage: A rare case report and review of the literature.

This case report describes a 48-year old female who presented with altered mental status, lower extremity weakness, low back pain and a recent history of subjective fevers and night sweats found to have posterior parieto-occipital and spinal subarachnoid hemorrhage on imaging. Further work-up revealed vasculitic changes in the intracranial vasculature and the external carotid artery on angiography. She also demonstrated positivity for perinuclear anti-neutrophil cytoplasmic (p-ANCA) antibodies overall consistent with ANCA associated central nervous system vasculitis (AAV). The present case describes a rare and new presentation of AAV that caused both a cerebral and spinal subarachnoid hemorrhage. There has been no documentation of spinal subarachnoid hemorrhage associated with primary or secondary vasculitis in the literature. Ultimately, this case demonstrates the important finding that AAV can have spinal cord manifestations and cervical vasculature involvement along with the more classic intra-cranial vasculitis findings.

Immune cell profiling in the cerebrospinal fluid of patients with primary angiitis of the central nervous system reflects the heterogeneity of the disease.

Primary angiitis of the central nervous system (PACNS) is a rare and heterogeneous inflammatory disease of the CNS vasculature with poorly understood pathophysiology. Comprehensive immune-cell phenotyping revealed increased frequencies of leukocytes in the cerebrospinal fluid (CSF) of PACNS patients compared to patients with multiple sclerosis, ischemic stroke, and somatoform disorders (n = 18 per group). Changes in the intrathecal immune-cell profile were heterogeneous in PACNS. While proportions of T-cell subsets remained unaltered, some PACNS patients showed a shift toward NK- or B cells. Intrathecal immunoglobulin synthesis was observed in a subgroup of PACNS patients with an increased frequency of antibody producing plasma cells.

Vasculitis in the Central Nervous System.

Central nervous system (CNS) vasculitides are a heterogeneous group of disorders characterized by an inflammatory cell infiltration and necrosis of blood vessel walls in the brain, spinal cord, and the meninges. The CNS complications are likely to be fatal without judicious use of immunosuppression; thus, early diagnosis may prevent from damage and disability. This chapter updates our knowledge on CNS vasculitis-related immunological mechanisms, neurological complications, diagnosis, and management.

What's in a name?

A 51-year-old man with rheumatoid arthritis and diabetes mellitus presented with new onset left-sided hemiparesis, left-sided neglect, and left-sided incongruous, denser inferiorly, homonymous hemianopsia. Magnetic resonance image of the brain showed prominent swelling of the right frontal, parietal, and occipital lobes greater than on the left with significant change in the fluid-attenuated inversion recovery signal in the gray matter. Perinuclear antineutrophil cytoplasmic antibodies titers were elevated, and skin biopsy demonstrating leukocytoclastic vasculitis. He showed marked clinical and radiographic improvement in association with recovery of vascular abnormalities after the initiation of prednisone, pulse therapy with methylprednisolone, and methotrexate. Clinicians should be aware of the possibility of neuro-ophthalmic manifestations of rheumatoid arthritis, including rheumatoid arthritis-related vasculitis causing homonymous hemianopsia.

Cognitive and affective dysfunctions in autoimmune thyroiditis.

Hashimoto's thyroiditis (HT) is the most frequent cause of hypothyroidism in areas with sufficient iodine intake. While the impact of thyroid function on mood and cognition is well known, only in the recent years, an increasing number of studies report on the association of HT with cognitive and affective disturbances also in the euthyroid state. Recent imaging studies have shown that these impairments are accompanied by altered brain perfusion, in particular, in the frontal lobe and a reduced gray matter density in the left inferior gyrus frontalis. Brain function abnormalities in euthyroid patients with HT may be subtle and only detected by specific testing or even severe as it is the case in the rare neuropsychiatric disorder Hashimoto's encephalopathy (HE). The good response to glucocorticoids in patients with HE indicates an autoimmune origin. In line with this, the cognitive deficits and the high psycho-social burden in euthyroid HT patients without apparent signs of encephalopathy appear to be associated with anti-thyroid peroxidase auto-antibody (TPO Abs) levels. Though in vitro studies showing binding of TPO Abs to human cerebellar astrocytes point to a potential direct role of TPO Abs in the pathogenesis of brain abnormalities in HT patients, TPO Abs may function only as a marker of an autoimmune disorder of the central nervous system. In line with this, anti-central nervous system auto-antibodies (CNS Abs) which are markedly increased in patients with HT disturb myelinogenesis in vitro and, therefore, may impair myelin sheath integrity. In addition, in HT patients, production of monocyte- and T-lymphocyte-derived cytokines is also markedly increased which may negatively affect multiple neurotransmitters and, consequently, diverse brain neurocircuits.

Treatment of primary CNS vasculitis with rituximab: case report.

Primary CNS vasculitis (PCNSV) is an uncommon disorder of unknown cause that is restricted to brain and spinal cord. Glucocorticoids alone or in combination with cyclophosphamide achieve a favorable response in most patients.(1,2) However, some patients are intolerant or respond poorly to cyclophosphamide; therefore, there is the need for new treatment options. We report a patient with PCNSV who appeared to respond to treatment with corticosteroids and rituximab. This study was approved by the Mayo Clinic Institutional Review Board and written informed patient consent to perform the study was obtained.

Diagnosis and classification of central nervous system vasculitis.

Central nervous system vasculitis is one of the foremost diagnostic challenges in rheumatology. It results in inflammation and destruction of the vasculature within the CNS. When vasculitis is confined to brain, meninges or spinal cord, it is referred to as primary angiitis of the CNS. Secondary CNS vasculitis occurs in the setting of a systemic vasculitis, auto-inflammatory or infectious disease. Prompt and accurate diagnosis of CNS vasculitis is essential to prevent irreversible brain damage, and to secure precise treatment decisions. Progressive debilitating and unexplained neurological deficits, associated with abnormal cerebrospinal fluid is the typical picture of the disease. Biopsy of the brain remains the gold standard diagnostic test. The differential diagnosis of CNS vasculitis is highly diverse with a broad array of mimics at the clinical, radiographic and angiographic levels.

CNS vasculitis and stroke in neonatal lupus erythematosus: a case report and review of literature.

Neonatal lupus erythematosus refers to the clinical spectrum of cardiac, cutaneous and other systemic abnormalities in neonates born to mothers with autoantibodies against Ro/SSA and La/SSB antigens. Isolated central nervous system involvement is very rare and has been described as transient vasculopathy only. We describe a 2-months-old girl who presented with acute ischemic stroke secondary to central nervous system vasculitis without any cardiac, cutaneous or hematological manifestations. The mother was pauci-symptomatic with raised anti-Ro autoantibody titers; the baby was positive for autoantibodies against Ro-antigen. Angiography confirmed vasculitis in cerebral vasculature. Our case highlights that neonatal lupus erythematosus can present with isolated nervous system manifestations and the vascular damage can be permanent in the form of vasculitis. Early recognition will help pediatricians identify such possible permanent complications in newborns with neonatal lupus erythematosus. A review of previously reported central nervous system manifestations of neonatal lupus is also presented.

Immune activation in amyloid-ß-related angiitis correlates with decreased parenchymal amyloid-ß plaque load.

BACKGROUND: Primary angiitis of the central nervous system (PACNS) is a rare but serious condition. A fraction of patients suffering from PACNS concurrently exhibit pronounced cerebral amyloid angiopathy (CAA) which is characterized by deposits of amyloid-ß (Aß) in and around the walls of small and medium-sized arteries of the brain. PACNS with CAA has been identified as a distinct disease entity, termed Aß-related angiitis (ABRA). Evidence points to an immune reaction to vessel wall Aß as the trigger of vasculitis. OBJECTIVE: To investigate whether the inflammatory response to Aß has (1) any effect on the status of immune activation in the brain parenchyma and (2) leads to clearance of Aß from brain parenchyma. METHODS: We studied immune activation and Aß load by quantitative immunohistochemical analysis in brain parenchyma adjacent to affected vessels in 11 ABRA patients and 10 matched CAA controls. RESULTS: ABRA patients showed significantly increased immune activation and decreased Aß loads in the brain parenchyma adjacent to affected vessels. CONCLUSION: Our results are in line with the hypothesis of ABRA being the result of an excessive immune response to Aß and show that this can lead to enhanced clearance of Aß from the brain parenchyma by immune-mediated mechanisms.

Cholestatic liver disease after rituximab and adalimumab and the possible role of cross-reacting antibodies to Fab 2 fragments.

BACKGROUND: Millions of patients are treated with therapeutic monoclonal antibodies (Tmabs) for miscellaneous diseases. We investigated sera from six patients who received immune globulin, from one patient with refractory anti-neutrophil-cytoplasmic antibody (ANCA)-associated granulomatosis with polyangiitis (GPA) who developed two episodes of acute cholestatic liver disease, one after treatment with rituximab and a second after adalimumab and a healthy control group. METHODS: Three sera from the patient and six sera from patients who received immune globulin were analyzed for antibodies to rituximab and adalimumab by ELISA. Additionally, sera from the patients and from nine healthy blood donors were coated with the Fab fragment of an unrelated humanized monoclonal antibody, with human Fc proteins as well as a mouse IgG globulin. RESULTS: Viral serology for hepatitis A, B, C and autoantibodies specific for autoimmune liver disorders were negative. In all three sera from the patient antibodies to rituximab could be detected, but also antibodies to adalimumab were present even at time points when the patient had not yet received adalimumab, indicating cross reactivity between both substances. Testing against an unrelated human Fab fragment revealed positive results, indicating that the patient had antibodies against human Fab fragments in general. The Fc proteins were negative, and patients' sera did also not react with mouse IgG globulins. Remarkably, 2 out of 5 patients which were treated with immune globulin had antibodies against human Fab fragments in general whereas in none of the samples from healthy controls antibodies to Fab fragment could be detected. CONCLUSION: This is the first study demonstrating cholestatic liver disease induced by two different Tmabs. Cross - reacting antibodies to Fab2 fragments in general are probably involved. Further studies must show if these Fab2 antibodies in general are related with drug-induced side effects and accelerated drug clearance in patients on Tmab therapy.

Neuro-Behçet's disease, its mimickers and anti-TNF therapy: a case-based review.

When the central nervous system is the primary affected site in an initial attack of Behçet's disease (BD), the differential diagnosis is particularly challenging. Because the specificity of immunobiologic therapy is growing, the specific diagnosis may impact the chosen therapy. For instance, anti-tumour necrosis factor agents are efficacious in BD but may be harmful in multiple sclerosis or systemic lupus erythematosus. We present two cases with similar neurological features but different diagnosis (BD and systemic lupus erythematosus) as a starting point to review diagnostic and therapeutic approaches for neuro-BD and its differential diagnoses.