New treatment strategies in large-vessel vasculitis

A new era for the treatment of inflammatory autoimmune diseases by interleukin-6 blockade strategy

Interleukin-6 (IL-6) is a cytokine with redundant and pleiotropic activities, and its synthesis is tightly regulated by transcriptional and posttranscriptional mechanisms. When infections and tissue injuries occur, IL-6 synthesis is promptly induced and provides an emergent signal that contributes to host defense through the stimulation of acute-phase responses, immune reactions, and hematopoiesis. After the environmental stress is removed from the host, the production of IL-6 is terminated. However, dysregulated continual synthesis of IL-6 is involved in the development of chronic inflammatory autoimmune diseases. For this reason, tocilizumab, a humanized anti-IL-6 receptor antibody, was developed. Worldwide clinical trials have demonstrated the outstanding efficacy of tocilizumab in rheumatoid arthritis, systemic juvenile idiopathic arthritis, and Castleman's disease; thus, a new era has come for the treatment of these diseases, which were previously considered intractable. Moreover, favorable results from off-label use of tocilizumab strongly suggest that it will be widely applicable for various refractory inflammatory autoimmune diseases. In this context, the mechanism for the continual synthesis of IL-6 needs to be elucidated in order to investigate the pathogenesis of specific diseases and to facilitate the development of more specific therapeutic strategies.

[Established medications : new areas of application]

During the last 10 years several new medications from hemato-oncology and transplantation medicine have been transferred to rheumatology. Additionally, medications which are approved for rheumatoid arthritis were increasingly also studied and used for other systemic inflammatory rheumatic diseases. This is especially the case for rituximab and mycophenolate and to a lesser extent also for leflunomide, tumor necrosis factor (TNF) antagonists, tocilizumab and abatacept. Recently, rituximab was approved for severe granulomatosis with polyangiitis (GPA) and microscopic polyangiitis (MPA) after the publication of two prospective randomized trials in 2010. The situation concerning rituximab is much more problematic for systemic lupus erythematosus (SLE) where randomized placebo-controlled trials exist but unfortunately did not meet the primary endpoint requirements (too many highly effective additional forms of treatment in both arms and unsuitable endpoints), although data from registries suggest efficacy especially in cases resistant to treatment. In the case of mycophenolate (MPS) the problem with SLE is totally different. All prospective trials met the endpoints and in one trial MPS was even superior to azathioprine for treatment of lupus nephritis (LN) which led to the recommendation of MPS for induction and maintenance in LN by EULAR and EDTRA as well as more recently by the ACR. However, MPS still is not approved for SLE or LN. The present manuscript gives an overview of existing data for selected connective tissue diseases and vasculitides (for which at least larger retrospective case series or registry data exist) being treated with medications approved for other indications.

Takayasu arteritis: criteria for surgical intervention should not be ignored

Takayasu aortoarteritis is a rare, chronic granulomatous panarteritis with significant morbidity amongst young patients. Current challenges include a lack of awareness about the condition, delays in diagnosis due to its varied presentation, and suboptimal methods for assessing disease activity. The development of noninvasive imaging including magnetic resonance angiography and positron emission tomography is aiding earlier diagnosis. Early initiation of immunosuppressive treatment is crucial to control active inflammation and minimize arterial injury. Recent studies investigating biological agents such as tumour necrosis factor-α antagonists are encouraging. Surgical revascularization should only be undertaken following careful consideration, as restenosis is common. The indications for considering intervention include uncontrolled hypertension due to renal artery stenosis, severe symptomatic coronary artery or cerebrovascular disease, severe aortic regurgitation, stenotic or occlusive lesions resulting in critical limb ischemia, and aneurysms at risk of rupture. In these cases, the risk benefit ratio for intervention is good. Open surgery, at present, has better outcomes compared to endovascular techniques. However, technological advances in endovascular treatment are continually improving. Controlling disease activity prior to and following revascularization is key to preventing complications. A multidisciplinary approach to the diagnosis and management of Takayasu arteritis is essential to achieve satisfactory patient outcomes.

Recurrent erythema nodosum: a red flag sign of hidden systemic vasculitis

Takayasu's arteritis is a rare, systemic vasculitis with varied presentations across multiple medical specialities. Here, we present a young woman who had recurrent episodes of erythema nodosum on the background of a low-grade fever and no vascular manifestations. The presence of a high erythrocyte sedimentation rate generated a high index of suspicion for underlying vasculitis, and radioimaging confirmed the suspicion of Takayasu's arteritis. The patient was found to have type III diseases in the vasculitic stage and was managed with systemic corticosteroids.