Assessment of systemic vasculitis

The role of transcription factors in the pathogenesis and therapeutic targeting of vascular diseases

Transcription factors (TFs) constitute an essential component of epigenetic regulation. They contribute to the progression of vascular diseases by regulating epigenetic gene expression in several vascular diseases. Recently, numerous regulatory mechanisms related to vascular pathology, ranging from general TFs that are continuously activated to histiocyte-specific TFs that are activated under specific circumstances, have been studied. TFs participate in the progression of vascular-related diseases by epigenetically regulating vascular endothelial cells (VECs) and vascular smooth muscle cells (VSMCs). The Krüppel-like family (KLF) TF family is widely recognized as the foremost regulator of vascular diseases. KLF11 prevents aneurysm progression by inhibiting the apoptosis of VSMCs and enhancing their contractile function. The presence of KLF4, another crucial member, suppresses the progression of atherosclerosis (AS) and pulmonary hypertension by attenuating the formation of VSMCs-derived foam cells, ameliorating endothelial dysfunction, and inducing vasodilatory effects. However, the mechanism underlying the regulation of the progression of vascular-related diseases by TFs has remained elusive. The present study categorized the TFs involved in vascular diseases and their regulatory mechanisms to shed light on the potential pathogenesis of vascular diseases, and provide novel insights into their diagnosis and treatment.

Reuma.pt/vasculitis - the Portuguese vasculitis registry

Background

The vasculitides are a group of rare diseases with different manifestations and outcomes. New therapeutic options have led to the need for long-term registries. The Rheumatic Diseases Portuguese Register, Reuma.pt, is a web-based electronic clinical record, created in 2008, which currently includes specific modules for 12 diseases and > 20,000 patients registered from 79 rheumatology centres. On October 2014, a dedicated module for vasculitis was created as part of the European Vasculitis Society collaborative network, enabling prospective collection and central storage of encrypted data from patients with this condition. All Portuguese rheumatology centres were invited to participate. Data regarding demographics, diagnosis, classification criteria, assessment tools, and treatment were collected. We aim to describe the structure of Reuma.pt/vasculitis and characterize the patients registered since its development.

Results

A total of 687 patients, with 1945 visits, from 13 centres were registered; mean age was 53.4 ± 19.3 years at last visit and 68.7% were females. The most common diagnoses were Behçet’s disease (BD) (42.5%) and giant cell arteritis (GCA) (17.8%). Patients with BD met the International Study Group criteria and the International Criteria for BD in 85.3 and 97.2% of cases, respectively. Within the most common small- and medium-vessel vasculitides registered, median [interquartile range] Birmingham Vasculitis Activity Score (BVAS) at first visit was highest in patients with ANCA-associated vasculitis (AAV) (17.0 [12.0]); there were no differences in the proportion of patients with AAV or polyarteritis nodosa who relapsed (BVAS≥1) or had a major relapse (≥1 major BVAS item) during prospective assessment (p = 1.00, p = 0.479). Biologic treatment was prescribed in 0.8% of patients with GCA, 26.7% of patients with AAV, and 7.6% of patients with BD. There were 34 (4.9%) deaths reported.

Conclusions

Reuma.pt/vasculitis is a bespoke web-based registry adapted for routine care of patients with this form of rare and complex diseases, allowing an efficient data-repository at a national level with the potential to link with other international databases. It facilitates research, trials recruitment, service planning and benchmarking.

Clinical analysis of 36 cases of autoimmune pancreatitis in China

BACKGROUND

To improve the early identification of autoimmune pancreatitis in China by a retrospective analysis of clinical data from AIP patients.

METHODOLOGY/PRINCIPAL FINDINGS

The analysis included 36 patients admitted by the surgery department of our hospital from January 2003 to October 2011 whose postoperative pathological confirmations were consistent with the histological criteria of Honolulu Consensus Document. The clinical phenotypes associated with the histopathologic patterns of LPSP and IDCP were referred to as type 1 and type 2 of AIP, respectively. A retrospective analysis of clinical features, serological data, pathological findings and imageological records was performed in line with the subtypes of AIP. Type 1 showing a sex predilection (males) was commonly more dominant than type 2 in all AIP. Type 2 without a gender predilection was, on average, a decade younger than type 1. Type 1 was inferior to type 2 in ALT, ALP and γ-GT with statistical significance (P = 0.044, 0.025 and 0.013). Type 1 was inferior to type 2 in AST with difference close to statistical significance (P = 0.072). Histopathology revealed frequent lymphoplasmacytic infiltration with less frequent infiltration of neutrophils, eosinophils and fibroblasts. Diffuse and intensive interstitial fibrosis could be seen. The changes of pancreatic head were more frequently seen in type 2 than in type 1 (P = 0.05). Plasma cells staining of IgG4 at a density of over 30 or more cells per high-power field appeared to be a specific finding in China with type 1. Imageology found a diffusely or focally enlarged pancreas, most frequently a mass or enlargement in the pancreatic head, characteristic capsule-like rim, calcification or pancreatic calculus and cystic degeneration.

CONCLUSIONS/SIGNIFICANCE

AIP is a unique type of chronic pancreatitis and has distinctive serological, pathological and imageological characteristics, which should be used for differentiation from pancreatic cancer.

Anti-neutrophil cytoplasmic autoantibodies: methodological aspects and clinical significance in systemic vasculitis

Antineutrophil cytoplasmic antibodies (ANCA) are the serological hallmark of some idiopathic systemic vasculitides, such as granulomatosis with polyangiitis (GPA), microscopic polyangiitis (MPA) and, to a lesser extent, Churg-Strauss syndrome (CCS), the so-called ANCA-associated vasculitides (AAV). ANCA were first detected by immunofluorescence (IIFT), subsequently the target antigens myeloperoxidase (MPO) and proteinase 3 (PR3) were identified, allowing the development of the quantitative, antigen-specific assays. According to the guidelines, combining IIFT and PR3-ANCA/MPO-ANCA assures the optimal diagnostic specificity. Antigen specificity does not effectively differentiate among the different AAV, however C-ANCA/PR3-ANCA are mainly found in GPA, while P-ANCA/MPO-ANCA are more prevalent in MPA and CSS. Despite their diagnostic value, the performance of the widespread immunometric assays for ANCA testing is disappointing, particularly for the low sensitivity. In recent years, more "sensitive" assays have been developed, using the microplate as well as fully the automated technologies, with promising preliminary results. ANCA, may be detected in a number of pathological conditions other than small vessel vasculitis. However, in most of these non-vasculitic patients ANCA do not recognize MPO or PR3 as target antigens, but other granulocyte components, often multiple or unknown specificities. A positive ANCA result by itself is not diagnostic for AAV, clinical evidence and possibly histological confirmation are always required. On the other hand, a negative test result cannot completely rule out a diagnosis of AAV, as AAV without detectable ANCA exist. The appropriate use of ANCA testing strongly improves the diagnostic accuracy and clinical usefulness of the results.

Acute vasculitis resulting in free flap failure: the importance of early recognition and options for management

Unusual or unexpected medical causes for free flap failure do occur but are uncommon. We present a rare case of a fibula free flap failure due to an acute vasculitis which was undiagnosed until after the flap had failed. In addition to two successful flap salvages and intravenous heparin, an epoprostenol infusion was commenced but a third salvage was not successful. The vasculitis resulted in marked blood vessel wall thickening, and cutaneous manifestations which presented as late signs. High peri-nuclear anti nuclear cytoplasmic antibody (pANCA) and myeloperoxidase (MOP) titres were subsequently found and histology from several blood vessels showed marked inflammation throughout the wall. A diagnosis of microscopic polyangiitis was made and high dose steroids were subsequently commenced. Interestingly, he had vasculitis several years previously treated with oral steroids but had been discharged from the rheumatology clinic. This rare case illustrates the potential hazards of free flap surgery in the vasculitides and discusses the warning signs and various management options to reduce the likelihood of flap failure in these patients.

Differentiation of autoimmune pancreatitis from pancreas cancer: utility of anti-amylase and anti-carbonic anhydrase II autoantibodies

Purpose

To investigate the utility of different combinations of serum anti-carbonic anhydrase II antibodies (CA II Abs), anti-α amylase antibodies (AMY-α Abs) and IgG4 levels for the diagnosis of autoimmune pancreatitis (AIP).

Methods

We recruited 93 patients with clinical suspicion for AIP and 94 patients as control groups between June 2003 and October 2009. Serum antibodies were measured using homemade enzyme linked immunosorbent assay and IgG4 levels were determined by nephelometry.

Results

Both CA-II Abs and AMY-α Abs had the highest sensitivity (83%) although AMY-α Abs (89%) were more specific than CA-II Abs (75%). The presence of increased IgG4 levels was the most specific serological marker (94%), but it had the lowest sensitivity (58%). The combination of the three serological markers altogether had the highest specificity (99%) and positive predictive value (PPV) (86%), but they had a rather low sensitivity (50%). When we combined CA-II Abs and AMY-α Abs without IgG4 levels, we got the highest sensitivity (75%) and negative predictive value (98%) but the specificity and the PPV decreased to 93 and 50%, respectively. Importantly, AMY-α Abs were not detected in pancreas cancer.

Conclusions

The presence of serum CA-II and AMY-α Abs with increased IgG4 is useful in the differential diagnosis of AIP from pancreatic cancer.

Pathogenesis of Takayasu's arteritis: a 2011 update

While our knowledge of the pathogenesis of Takayasu's arteritis (TA) has considerably improved during the last decade, the exact pathogenic sequence remains to be elucidated. It is now hypothesised that an unknown stimulus triggers the expression of the 65kDa Heat-shock protein in the aortic tissue which, in turn, induces the Major Histocompatibility Class I Chain-Related A (MICA) on vascular cells. The γδ T cells and NK cells expressing NKG2D receptors recognize MICA on vascular smooth muscle cells and release perforin, resulting in acute vascular inflammation. Pro-inflammatory cytokines are released and increase the recruitment of mononuclear cells within the vascular wall. T cells infiltrate and recognize one or a few antigens presented by a shared epitope, which is associated with specific major Histocompatibility Complex alleles on the dendritic cells, these latter being activated through Toll-like receptors. Th1 lymphocytes drive the formation of giant cells through the production of interferon-γ, and activate macrophages with release of VEGF resulting in increased neovascularisation and PDGF, resulting in smooth muscle migration and intimal proliferation. Th17 cells induced by the IL-23 microenvironnement also contribute to vascular lesions through activation of infiltrating neutrophils. Although still controversial, dendritic cells may cooperate with B lymphocytes and trigger the production of anti-endothelial cell auto-antibodies resulting in complement-dependent cytotoxicity against endothelial cells. In a near future, novel drugs specifically designed to target some of the pathogenic mechanisms described above could be expanding the physician's therapeutic arsenal in Takayasu's arteritis.