Dramatic MRI improvement with refractory neurosarcoidosis treated with infliximab

Neurosarcoidosis: an update on diagnosis and therapy

INTRODUCTION

Clinically overt granulomatous involvement of the nervous system (i.e., neurosarcoidosis) can be seen in up to 10% of patients with sarcoidosis. Establishing a diagnosis of neurosarcoidosis is often challenging due to the heterogeneity of clinical presentations that are sometimes non-specific, and inaccessibility of tissue confirmation. Recommended treatments are based on expert opinions that are derived from clinical experience and limited data from retrospective studies, as data from randomized controlled studies are limited.

AREA COVERED

In this article, we comprehensively review all available literature on epidemiology, clinical presentations, diagnosis, treatment, and outcomes of neurosarcoidosis. We also offer our opinions on diagnostic approach and treatment strategy.

EXPERT OPINION

Given the invasive nature and the limited sensitivity of biopsy of the nervous system, diagnosis of neurosarcoidosis is usually made when ancillary tests (such as magnetic resonance imaging and cerebrospinal fluid analysis) are compatible, and alternative diagnoses are reasonably excluded in patients with established extraneural sarcoidosis. Several factors must be taken into consideration to formulate the initial treatment strategy, including the extent of the disease, severity, functional impairment, comorbidities and patient's preference. In addition, treatment regimen of neurosarcoidosis should be formulated with an emphasis on long-term strategy.

Neurosarcoidosis

Neurosarcoidosis occurs in 3% to 10% of patients with sarcoidosis. Cranial neuropathy and meningeal involvement are the most common manifestations, but any part of the nervous system can be affected. Definite diagnosis requires the presence of noncaseating granuloma in the nervous system, although histopathologic confirmation is often not obtainable. Moderate to high dose of glucocorticoids is the main therapy for neurosarcoidosis. Relapse often occurs after the dose of glucocorticoids is tapered down, often necessitating the use of steroid-sparing immunosuppressive agents.

Characteristics and Long-Term Outcome of Neurosarcoidosis: A Population-Based Study from 1976-2013

BACKGROUND/AIMS

Neurosarcoidosis is a rare condition with serious health consequences. However, little is known about clinical characteristics and outcome of neurosarcoidosis in the community setting.

METHODS

Patients with neurosarcoidosis were identified from a previously described cohort of patients with incident sarcoidosis from Olmsted County, Minnesota, United States from 1976 to 2013 using individual medical record review. Data on clinical characteristics, treatment, and outcome were collected.

RESULTS

Neurological involvement by sarcoidosis occurred in 11 patients (3% of all patients with sarcoidosis). Cranial neuropathy was the most common type of neurological disease (5 patients; 45%) followed by peripheral neuropathy (3 patients; 27%), and meningitis (3 patients; 27%). Cerebrospinal fluid (CSF) pleocytosis and elevated CSF protein levels were observed in patients with meningitis, intramedullary spinal cord sarcoidosis, intracranial mass lesion and some patients with cranial neuropathy but were normal in patients with peripheral neuropathy. All patients received high-dose glucocorticoids as initial treatment and almost all responded to this therapy. Relapse after glucocorticoid dose reduction necessitated subsequent treatment with steroid-sparing agents in 4 patients.

CONCLUSION

Neurosarcoidosis is an uncommon manifestation of sarcoidosis. Neurosarcoidosis manifestations generally responded well to high-dose glucocorticoids in the majority of patients, but relapse was common.

Neurosarcoidosis: diagnostic approaches and therapeutic strategies

PURPOSE OF REVIEW

The aims of this article are to discuss the epidemiology, pathophysiology and clinical phenomenology of neurosarcoidosis, as well as current approaches to diagnosis and treatment. This review focuses on central nervous system (CNS) complications of sarcoidosis.

RECENT FINDINGS

Neurosarcoidosis is a rare disorder with diverse clinical manifestations and outcomes. It is often difficult to diagnose and even more difficult to treat. New diagnostic approaches include the use of [¹⁸F]-fluorodeoxyglucose PET to identify potential biopsy sites. Success has been reported in the treatment of steroid refractory cases with disease-modifying therapies that were originally designed to manage other chronic inflammatory conditions by neutralizing key cytokines or depleting leukocyte subsets.

SUMMARY

The diagnosis and management of neurosarcoidosis can be challenging. Currently, the disorder is treated with corticosteroids in combination with global immunosuppressant agents and/or immunomodulatory monoclonal antibodies, such as infliximab. The development of novel CNS penetrant drugs that are particularly effective at inhibiting granuloma formation would represent a significant therapeutic advance. Future progress will be informed by a deeper understanding of the pathways underlying the granulomatous inflammation characteristic of sarcoidosis and by an increased appreciation of how sarcoid lesions evolve in the CNS microenvironment.

Dural lesions mimicking meningiomas: A pictorial essay

The purpose of this essay was to illustrate the radiological and pathological findings in a wide spectrum of dural lesions mimicking meningiomas. Familiarity with and knowledge of these findings will narrow the differential diagnosis and provide guidance for patient management. In this pictorial review, we describe the following entities: Solitary fibrous tumors, hemangiopericytoma, gliosarcoma, leiomyosarcoma, dural metastases, Hodgkin’s disease, plasmocytoma, Rosai-Dorfman disease, neurosarcoidosis, melanocytic neoplasms and plasma cell granuloma.

Medically refractory neurosarcoidosis treated with infliximab

Neurosarcoidosis can worsen despite standard immunosuppressive therapy, a situation for which there is no established medical management. We present three cases of medically refractory neurosarcoidosis treated with infliximab. All three patients showed a clinical response to this treatment and side effects were limited. A summary of reported cases of neurosarcoidosis treated with infliximab is included. This case series supports a role for infliximab in the treatment of patients with medically refractory neurosarcoidosis.

La crosse virus encephalitis preceding neurosarcoidosis diagnosed by brain biopsy

Childhood neurosarcoidosis is rare, and its etiology is unknown. La Crosse virus is one of the most common causes of encephalitis in North America. We report the case of a 12-year-old boy who had La Crosse virus encephalitis and subsequently developed imaging and pathologic findings suggestive of neurosarcoidosis. He presented with acute onset of transient aphasia 4 months after an episode of encephalitis; serology results at the time of aphasia were positive for La Crosse virus. Brain MRI revealed diffuse subcortical nodular lesions. His serum angiotensin-converting enzyme level was elevated, and brain biopsy revealed noncaseating granuloma. It is interesting to note that he has had no recurrence of aphasia; repeat MRI showed significant improvement of nodular lesions without therapy. To our knowledge, this is the first case of La Crosse virus encephalitis associated with neurosarcoid findings.

[TNFα blocking agents and sarcoidosis: an update]

Increased production of TNFα by alveolar macrophages and involvement of TNFα in granuloma formation suggest that this cytokine is involved in the pathophysiology of sarcoidosis. The three available TNFα blocking agents have been tested in sarcoidosis refractory to corticosteroids or immunosuppressive drugs. Data are available from isolated case reports or limited series of patients treated in open label trials with favourable issue with anti-TNFα monoclonal antibodies. Two randomized placebo controlled studies evaluated the efficacy of infliximab in pulmonary and extra-pulmonary sarcoidosis, showing that infliximab improves significantly extra-pulmonary disease. There is no significant difference between infliximab and placebo in the treatment of pulmonary manifestations. Etanercept showed no efficacy for treating ocular sarcoidosis in a controlled trial and for pulmonary disease in an open label trial. Paradoxical cases of proven sarcoidosis have been reported in patients receiving anti-TNFα agents for chronic inflammatory rheumatic diseases. A literature review identified 28 cases, including 16 with etanercept, eight with infliximab and four with adalimumab. Although these cases were mainly reported with etanercept, paradoxical sarcoidosis has been reported with the three available anti-TNFα agents, suggesting a class effect. Changes in the cytokine balance may be involved in these cases of induced sarcoidosis, which must be known by the clinician.

Neurologic presentations of sarcoidosis

Neurosarcoidosis is a diagnostic consideration in diverse clinical settings. Efforts should be made to secure pathologic confirmation of systemic sarcoidosis; only rarely is central nervous system (CNS) pathologic confirmation available. CNS infection and malignancy should be reasonably excluded before making a diagnosis of CNS sarcoidosis. Corticosteroid therapy alone may not be sufficient to treat neurosarcoidosis; adjunct immunosuppressive agents are increasingly used to achieve an optimal clinical outcome.

Neurosarcoidosis

Although neurosarcoidosis seems to occur in only 5% to 10% of patients who have sarcoidosis, it may lead to significant complications. The diagnosis of neurosarcoidosis usually relies on indirect information from imaging and spinal fluid examination. Although MR imaging remains the most sensitive technique for detecting neurologic disease, other tests, including positron emission tomography scanning and cerebral spinal fluid examination, can provide important information. The role of immunosuppressive agents such as methotrexate, cyclophosphamide, and azathioprine has been expanded, and these agents should be considered for the treatment of some manifestations of neurosarcoidosis. Reports of the antitumor necrosis factor agent infliximab suggest that this drug can be helpful for patients who have neurosarcoidosis.

[Refractory neurosarcoidosis and infliximab: a growing experience]

Neurosarcoidosis is a rare disease that can involve all the nervous system with variable clinical onset and prognosis. The initial therapeutic approach is mainly based on corticosteroids and immunosuppressive agents. Treatment of refractory forms of neurosarcoidosis is not well established and emerging immunomodulating drugs like infliximab have been recently tested. The clinical report of a new case of neurosarcoidosis responding to infliximab is followed by a review of the new therapeutic agents available for the treatment of refractory neurosarcoidosis.