Infliximab leads to a rapid but transient improvement in endothelial function in patients with primary systemic vasculitis

Arterial stiffness, endothelial dysfunction and impaired fibrinolysis are pathogenic mechanisms contributing to cardiovascular risk in ANCA-associated vasculitis

Cardiovascular disease is a complication of systemic inflammatory diseases including anti-neutrophil cytoplasm antibody-associated vasculitis (AAV). The mechanisms of cardiovascular morbidity in AAV are poorly understood, and risk-reduction strategies are lacking. Therefore, in a series of double-blind, randomized case-control forearm plethysmography and crossover systemic interventional studies, we examined arterial stiffness and endothelial function in patients with AAV in long-term disease remission and in matched healthy volunteers (32 each group). The primary outcome for the case-control study was the difference in endothelium-dependent vasodilation between health and AAV, and for the crossover study was the difference in pulse wave velocity (PWV) between treatment with placebo and selective endothelin-A receptor antagonism. Parallel in vitro studies of circulating monocytes and platelets explored mechanisms. Compared to healthy volunteers, patients with AAV had 30% reduced endothelium-dependent vasodilation and 50% reduced acute release of endothelial active tissue plasminogen activator (tPA), both significant in the case-control study. Patients with AAV had significantly increased arterial stiffness (PWV: 7.3 versus 6.4 m/s). Plasma endothelin-1 was two-fold higher in AAV and independently predicted PWV and tPA release. Compared to placebo, both selective endothelin-A and dual endothelin-A/B receptor blockade reduced PWV and increased tPA release in AAV in the crossover study. Mechanistically, patients with AAV had increased platelet activation, more platelet-monocyte aggregates, and altered monocyte endothelin receptor function, reflecting reduced endothelin-1 clearance. Patients with AAV in long-term remission have elevated cardiovascular risk and endothelin-1 contributes to this. Thus, our data support a role for endothelin-blockers to reduce cardiovascular risk by reducing arterial stiffness and increasing circulating tPA activity.

The risk of endothelial and erectile dysfunctions in Behçet's disease: a comparative analysis of mucocutaneous and systemic patient groups

INTRODUCTION

Behçet's disease (BD) is a chronic inflammatory disease which can be limited to only mucocutaneous tissues or can affect different systems of the body.

AIM

To investigate the association of endothelial and erectile dysfunctions with BD, on the basis of comparative analysis between mucocutaneous and systemic BD.

MATERIAL AND METHODS

Thirty-eight men diagnosed with BD were included in the present study. The patients were stratified into two groups as mucocutaneous BD (n = 20, MBD group), and systemic BD (n = 18, SBD group). Erectile dysfunction (ED) was assessed using the Erectile Function domain of the International Index of Erectile Function (IIEF-EF) questionnaire. The coronary flow reserve (CFR) assessment was done for analysing endothelial dysfunction (EnD), and CFR < 2 was defined as EnD. Penile Doppler ultrasonography (PDU) was performed for ED. The demographic and clinical parameters, IIEF-EF score ED classification, CFR and PDU test findings were compared between two groups.

RESULTS

The median age was 34 (22-52) years in the overall population, and there was no difference between two groups (p = 0.558). Time from diagnosis was significantly longer (24 vs. 102 months, p = 0.021) and the use of immunosuppressive therapies was higher (0 vs. 70.6%, p < 0.001) in the SBD group. In overall, median CFR was 1.92 (1.1-5.96), and there was no difference between two groups (1.88 vs. 1.97, p = 0.812). The percentage of patients with CFR < 2 was similar in two groups (52.6% vs. 52.9%, p = 0.985). The ED status according to IIEF-EF was similar in two groups (45% vs. 27.8%, p = 0.538) as well as according to PDU analyses (10% vs. 16.7%, p = 0.544).

CONCLUSIONS

The increased risk of endothelial, and erectile dysfunctions should be considered in men who were diagnosed with mucocutaneous and systemic BD.

Do anti-tumour necrosis factor-α biologics affect subclinical measures of atherosclerosis and arteriosclerosis? A systematic review

AIMS

Inflammatory cytokines, particularly tumour necrosis factor-α (TNFα), are thought to promote arterial disease through a variety of mechanisms leading to arteriosclerosis and atherosclerosis. We reviewed the existing evidence of the effect of anti-TNFα treatment on arteriosclerosis and atherosclerosis in chronic inflammatory disease.

METHODS

We performed a systematic review of studies examining effects of monoclonal antibodies against TNFα on subclinical measures of arteriosclerosis (arterial pulse wave velocity) and atherosclerosis (endothelial function measured by flow-mediated dilation or forearm blood flow responses to endothelium-dependent agonists, and common carotid intima-media thickness).

RESULTS

We identified 60 studies (of 854 potential studies identified using a systematic search) in which effects of anti-TNFα biologics on these measures were assessed in patients receiving anti-TNFα therapy for a clinical indication (usually an inflammatory disease such as an inflammatory arthritis, psoriasis or inflammatory bowel disease). Of these, only 6 were randomised clinical controlled trials. Whilst many observational studies and noncontrolled studies reported positive findings, positive finding were reported in only 1 of 6 randomised clinical controlled trials.

CONCLUSIONS

There is no strong evidence for an effect of anti-TNFα biologics on the subclinical measures of arteriosclerosis or atherosclerosis examined in this review. This does not exclude a positive effect of TNFα biologics on clinical outcomes through alternate pathways including those induced by remission of the primary inflammatory disease.

Endothelial Nitric Oxide Pathways in the Pathophysiology of Dengue: A Prospective Observational Study

BACKGROUND

Dengue can cause increased vascular permeability that may lead to hypovolemic shock. Endothelial dysfunction may underlie this; however, the association of endothelial nitric oxide (NO) pathways with disease severity is unknown.

METHODS

We performed a prospective observational study in 2 Vietnamese hospitals, assessing patients presenting early (<72 hours of fever) and patients hospitalized with warning signs or severe dengue. The reactive hyperemic index (RHI), which measures endothelium-dependent vasodilation and is a surrogate marker of endothelial function and NO bioavailability, was evaluated using peripheral artery tonometry (EndoPAT), and plasma levels of l-arginine, arginase-1, and asymmetric dimethylarginine were measured at serial time-points. The main outcome of interest was plasma leakage severity.

RESULTS

Three hundred fourteen patients were enrolled; median age of the participants was 21(interquartile range, 13-30) years. No difference was found in the endothelial parameters between dengue and other febrile illness. Considering dengue patients, the RHI was significantly lower for patients with severe plasma leakage compared to those with no leakage (1.46 vs 2.00; P < .001), over acute time-points, apparent already in the early febrile phase (1.29 vs 1.75; P = .012). RHI correlated negatively with arginase-1 and positively with l-arginine (P = .001).

CONCLUSIONS

Endothelial dysfunction/NO bioavailability is associated with worse plasma leakage, occurs early in dengue illness and correlates with hypoargininemia and high arginase-1 levels.

The endothelium and its role in regulating vascular tone

The endothelium forms an important part of the vasculature and is involved in promoting an atheroprotective environment via the complementary actions of endothelial cell-derived vasoactive factors. Disruption of vascular homeostasis can lead to the development of endothelial dysfunction which in turn contributes to the early and late stages of atherosclerosis. In recent years an increasing number of non-invasive vascular tests have been developed to assess vascular structure and function in different clinical populations. The present review aims to provide an insight into the anatomy of the vasculature as well as the underlying endothelial cell physiology. In addition, an in-depth overview of the current methods used to assess vascular function and structure is provided as well as their link to certain clinical populations.

Inflammation and Microvascular and Macrovascular Endothelial Dysfunction in Rheumatoid Arthritis: Effect of Treatment

Objective.

To determine whether abnormalities in microvascular and macrovascular function in rheumatoid arthritis (RA) are associated with plasma markers [von Willebrand factor (VWF)] of endothelial dysfunction and inflammation [C-reactive protein (CRP)] and whether the abnormalities would be altered by treatment. Endothelial dysfunction and inflammation in RA may contribute to adverse cardiovascular events. Although endothelial dysfunction in RA has been demonstrated by altered plasma markers, the relationships with macrovascular and microvascular function are relatively unexplored.

Methods.

We recruited 66 patients with chronic RA, 48 community controls (CC), and 25 patients with diabetes and hypertension as a disease control group (DC). Subjects had venous blood sampled for plasma markers, and underwent laser Doppler perfusion imaging of forearm skin (to assess microvascular circulation) following acetylcholine and sodium nitroprusside iontophoresis, to assess endothelium-dependent and endothelium-independent responses, respectively. Brachial artery flow-mediated dilatation assessed endothelial dysfunction in a macrovascular bed. A subgroup of 29 patients with RA were assessed pretherapy and after 2–4 weeks of antirheumatic therapy.

Results.

As expected, patients with RA had higher CRP, erythrocyte sedimentation rate (ESR), and VWF. Endothelium-independent vasoreactivity was abnormal in RA, and this correlated negatively with CRP. All aspects of microvascular function were abnormal in the DC compared to the CC. Macrovascular function was preserved in RA but was abnormal in the DC group. Four weeks of antiinflammatory therapy reduced CRP and ESR but had no effect on any vascular function index in the patients with RA.

Conclusion.

Patients with RA have abnormal endothelium-independent microvascular function that correlates with inflammation but is not altered by short-term antiinflammatory therapy.

[Wegener's granulomatosis and microscopic polyangiitis]

Wegener's granulomatosis (WG) and microscopic polyangiitis (MPA) are primary systemic small vessel vasculitides, associated with a positive C/PR3-ANCA in WG and P/MPO-ANCA in MPA. The most prominently involved organs are the upper (only in WG) and lower respiratory tract and the kidneys. The diagnostic work-up is an interdisciplinary approach assessing disease stage and extent. Treatment is adapted to disease stage and extent and relies on a combination of a cytotoxic plus a tapering regimen of corticosteroids. Induction of remission in "early systemic" disease can be achieved with low-dose methotrexate. In severe generalized vasculitis cyclophosphamide (CYC) is the mainstay of therapy, in rapidly progressive glomerulonephritis in combination with plasmapheresis. After 3-6 months of induction CYC is switched to a maintenance treatment with azathioprine. Alternatives are leflunomide, mycophenolate or methotrexate (creatinine < 150 micromol/l). Age > or = 50 at diagnosis, renal dysfunction and pulmonary involvement are associated with higher mortality rates. The relapse rate is approximately 50% within 5 years, being higher in WG than MPA.

Atherosclerosis in ANCA-associated vasculitides

It is currently accepted that atherosclerosis is rather, or also, an inflammatory disease and, indeed, vasculitis is defined by inflammatory infiltrates in blood vessel walls, albeit initially by different predominant cell populations and in arteries of different calibers. As for other chronic systemic inflammatory diseases, premature and accelerated atherosclerosis has emerged during the last 5-10 years as an important facet of vasculitides, independently of the other risk factors of cardiovascular disease and also, apparently, corticosteroids. Chronic systemic inflammation, like persistently active vasculitis, might play a role in early atherosclerosis, through the actions of C-reactive protein (CRP), some adhesion molecules, and/or cytokines, as well as local inflammation, perhaps through locally secreted TNF-alpha and/or upregulation of matrix metalloproteinases and oxidative stress. Endothelial cell dysfunction and increased arterial stiffness have also been found in vasculitis patients. Notably, some vasculitis treatments were able to reverse some of these endothelial cell anomalies. Unlike antineutrophil cytoplasm autoantibodies (ANCA), which were not shown to correlate with a higher risk of atherosclerosis or cardiovascular events, autoantibodies to endothelial cells, heat-shock proteins, or oxidized-LDL may also be implicated, although these latter are now thought to protect against atherosclerosis. It is likely that other, as yet unidentified, factors facilitating atherosclerosis may play more important roles in vasculitides. Until their precise identification, it remains important to take into consideration and treat, every time it is necessary and possible, the other well-known cardiovascular risk factors.

Update on Cutaneous Vasculitis

Vasculitis presents with a range of clinical manifestations, many of which affect the skin. Diagnosing and classifying vasculitis can prove challenging. Particularly given the lack of unified criteria that are both useful as a research tool and clinically relevant. Also, vasculitis may be secondary to a wide range of conditions, making the prompt recognition and treatment of associated disorders essential for appropriate patient management. This article will highlight the classification, pathogenesis, clinical presentation, diagnosis, evaluation, and treatment of the cutaneous vasculitides.

Off-Label Uses of Biologic Agents in Dermatology: A 2006 Update

The introduction of a number of biologic therapies into the market has revolutionized the practice of dermatology. These therapies include adalimumab, alefacept, efalizumab, etanercept, infliximab, IVIg, omalizumab, and rituximab. Most dermatologists are familiar with the indications of these medications that have been approved by the Food and Drug Administration; however, numerous off-label uses have evolved. To update the reader on more recent uses of the biologics for off-label dermatologic use, this article will emphasize more recent published data from 2005 through the date of submission in May 2006.

Cutaneous vasculitis: diagnosis and management

Vasculitis is histologically defined as inflammatory cell infiltration and destruction of blood vessels. Vasculitis is classified as primary (idiopathic, eg, cutaneous leukocytoclastic angiitis, Wegener's granulomatosis) or secondary, a manifestation of connective tissue diseases, infections, adverse drug eruptions, or a paraneoplastic phenomenon. Cutaneous vasculitis, manifested as urticaria, purpura, hemorrhagic vesicles, ulcers, nodules, livedo, infarcts, or digital gangrene, is a frequent and often significant component of many systemic vasculitic syndromes such as lupus or rheumatoid vasculitis and antineutrophil cytoplasmic antibody-associated primary vasculitic syndromes such as Churg-Strauss syndrome. In most instances, cutaneous vasculitis represents a self-limited, single-episode phenomenon, the treatment of which consists of general measures such as leg elevation, warming, avoidance of standing, cold temperatures and tight fitting clothing, and therapy with antihistamines, aspirin, or nonsteroidal anti-inflammatory drugs. More extensive therapy is indicated for symptomatic, recurrent, extensive, and persistent skin disease or coexistence of systemic disease. For mild recurrent or persistent disease, colchicine and dapsone are first-choice agents. Severe cutaneous and systemic disease requires more potent immunosuppression (prednisone plus azathioprine, methotrexate, cyclophosphamide, cyclosporine, or mycophenolate mofetil). In cases of refractory vasculitis, plasmapheresis and intravenous immunoglobulin are viable considerations. The new biologic therapies that work via cytokine blockade or lymphocyte depletion such as tumor alpha inhibitor infliximab and the anti-B-cell antibody rituximab, respectively, are showing benefit in certain settings such as Wegener's granulomatosis, antineutrophil cytoplasmic antibody-associated vasculitis, Behçet's disease, and cryoglobulinemic vasculitis.