Maria Sole Chimenti

How to diagnose spondyloarthritis early? Accuracy of peripheral enthesitis detection by power Doppler ultrasonography

Objective Early diagnosis of spondyloarthritis (SpA) is sometimes difficult owing to the lack of reliable diagnostic criteria. The objective of this study was to determine the diagnostic accuracy of detecting enthesitis by power Doppler ultrasonography (PDUS) in patients with suspected SpA. Methods A prospective single-centre cohort study was performed in patients with symptoms suggestive of SpA (inflammatory back pain, arthritis, enthesitis or dactylitis, HLAB27+ uveitis) who underwent clinical examination, pelvic x-ray, MRI of lumbar spine/sacroiliac joints, HLA-B typing and other tests judged useful for diagnosis. Blinded PDUS examination of seven sites of enthesitis was performed at baseline. The gold standard was the diagnosis made by the referring rheumatologist according to the development of symptoms and findings, blinded to PDUS results, during routine follow-up for up to 2 years. Results Between November 2002 and October 2004, 118 patients were included in the study. After 2 years a definite diagnosis was retained for 99 patients (51 SpA and 48 non-SpA). PDUS detection of at least one vascularised enthesis provided good predictive value for diagnosing SpA (sensitivity 76.5%; specificity 81.3%; positive likelihood ratio 4.1; OR 14.1; p<0.0001). Vascularised enthesitis detected by PDUS and Amors criteria were the only independent contributors to a diagnosis of SpA in multivariate logistic regression (c-index=0.87). Alternatively, CART analysis resulted in a highly sensitive and specific diagnostic tree by combining PDUS with Amors criteria. Conclusions PDUS appears to be a valuable first-line diagnostic tool to confirm a diagnosis of SpA.

Complement and autoimmunity

The complement system is a component of the innate immune system. Its main function was initially believed to be limited to the recognition and elimination of pathogens through direct killing or stimulation of phagocytosis. However, in recent years, the immunoregulatory functions of the complement system were demonstrated and it was determined that the complement proteins play an important role in modulating adaptive immunity and in bridging innate and adaptive responses. When the delicate mechanisms that regulate this sophisticated enzymatic system are unbalanced, the complement system may cause damage, mediating tissue inflammation. Dysregulation of the complement system has been involved in the pathogenesis and clinical manifestations of several autoimmune diseases, such as systemic lupus erythematosus, vasculitides, Sjögren’s syndrome, antiphospholipid syndrome, systemic sclerosis, dermatomyositis, and rheumatoid arthritis. Complement deficiencies have been associated with an increased risk to develop autoimmune disorders. Because of its functions, the complement system is an attractive therapeutic target for a wide range of diseases. Up to date, several compounds interfering with the complement cascade have been studied in experimental models for autoimmune diseases. The main therapeutic strategies are inhibition of complement activation components, inhibition of complement receptors, and inhibition of membrane attack complex. At present, none of the available agents was proven to be both safe and effective for treatment of autoimmune diseases in humans. Nonetheless, data from preclinical studies and initial clinical trials suggest that the modulation of the complement system could constitute a viable strategy for the treatment of autoimmune conditions in the decades to come.

Unusual spindle cell squamous carcinoma in a renal transplant patient.

The histopathological diagnosis of spindle cell tumours is often difficult. We present a patient who developed a painful tumour on his head 6 years after renal transplantation. Histologically, the tumour was first interpreted as scar tissue with an unusual fibrohistiocytic component. Cytokeratins, desmin, CD31, CD34 and S100 could not be detected using conventional immunohistochemistry. After two recurrences and intensive immunohistochemical examinations, cytokeratin-positive tumour areas in direct connection with the epidermis were detected. The final diagnosis was therefore spindle cell squamous carcinoma. The patient finally died from brain metastases after experiencing further painful recurrences that were removed surgically. Our case underscores the importance of refined immunohistochemical methods in establishing the diagnosis of spindle cell squamous carcinomas, methods that should be taken into account especially if painful spindle cell tumours arise on sun-exposed skin in immunosuppressed patients.

Role of the complement system in rheumatoid arthritis and psoriatic arthritis: Relationship with anti-TNF inhibitors

The complement system is an essential component of innate immunity and also plays an important role in modulating adaptive immunity. It comprises more than 30 plasma and membrane-bound proteins and can be activated through three pathways: the classical, the alternative and the lectin pathways. Its activation contributes to the pathogenesis of several autoimmune and inflammatory conditions. The evidence of complement activation in synovial fluid of Rheumatoid Arthritis (RA) patients is abundant, while few data exist in Psoriatic Arthritis (PsA) patients. Levels of complement proteins are generally depressed in the synovial fluid of patients with RA, reflecting consumption of complement. On the other hand, elevated levels of several complement cleavage products have been observed in synovial fluid. Involvement of complement in the pathogenesis of RA was also confirmed in animal models of arthritis: mice deficient for complement proteins are protected against the development of collagen-induced arthritis and administration of the anti-C5 monoclonal antibody prevents the onset of this arthritis. In the last decade anti-tumor necrosis factor agents have shown to be effective for the treatment of both RA and PsA and some studies suggest that the interaction between TNFα and complement system may contribute to the pathogenesis of these diseases. Reduction of the complement activation could be one of the mechanism by which TNFα-inhibitors exert their effectiveness in inflammatory arthritides. Because of these findings, complement could be an attractive therapeutic target both in RA and in PsA.

Efficacy and Safety of Subcutaneous Anti-Tumor Necrosis Factor-Alpha Agents, Etanercept and Adalimumab, in Elderly Patients Affected by Psoriasis and Psoriatic Arthritis: An Observational Long-Term Study

Background: In elderly patients the management of psoriasis is challenging due to contraindications and a higher risk of side effects. Objective: Our retrospective study aimed to evaluate the long-term efficacy and safety profile of subcutaneous anti-tumor necrosis factor (anti-TNF) agents in elderly psoriatic patients. Methods: The study included 89 patients (aged ≥65 years) with plaque-type psoriasis and psoriatic arthritis treated with the subcutaneous anti-TNF-α agents etanercept or adalimumab as monotherapy for a long-term continuous period. Results: Efficacy results were consistent and stable over long-term observation, as expressed by mean Psoriasis Area and Severity Index (PASI) score variation, percentage of patients achieving PASI50 and PASI75 and by the improvement of articular indices, pain visual analogue scale (Pain-VAS) and 44-Joint Disease Activity Score (DAS44-ESR). The proportion of patients achieving PASI50 was 91.80 and 82.14% at week 156 with etanercept and adalimumab treatment, respectively, while the proportion of patients achieving PASI75 was 83.61 and 71.43% at week 156 when treated with etanercept and adalimumab, respectively. The mean DAS44-ESR score decreased from 5.80 to 0.89 and from 3.43 to 1.44 at week 156 and the mean Pain-VAS score decreased from 75.10 to 3.15 and from 71.30 to 18.26 at week 156 with etanercept and adalimumab treatment, respectively. Both treatment adherence and safety profile were good. Conclusions: Our study demonstrates that subcutaneous anti-TNF-α agents are appropriate in the long-term management of elderly patients.

The new era for the treatment of psoriasis and psoriatic arthritis: perspectives and validated strategies.

Psoriatic Arthritis (PsA) is a chronic inflammatory arthropathy associated with psoriasis. Psoriasis (PsO) is a chronic, inflammatory skin disease, characterized by hyperproliferation and aberrant differentiation of keratinocytes. PsA and PsO can be considered as a unique disease and are immune-mediated diseases and both innate and adaptive immunity play a role in their pathogenesis. Initially, PsO and PsA were thought to be Th1-mediated diseases, however, in the last years, several studies have shown the role of interleukin 17 (IL-17) and Th17 cells in the pathogenesis of PsA and PsO. Th17 cells have been detected in dermal infiltrates of psoriatic lesions as well as in synovial fluid. Interleukin (IL)-23, produced by antigen presenting cells (APC), especially by dendritic cells (DC), is the key regulator cytokine for Th17 and IL-17 production. In this review we discuss the role of IL-17 and IL-23 in the pathogenesis of PsO and PsA and their role as therapeutic targets for PsO and PsA treatment.

Autoantibodies in inflammatory arthritis.

Rheumatoid arthritis (RA) is a systemic chronic inflammatory disease characterized by extensive synovitis resulting in erosions of articular cartilage and marginal bone with joint destruction. The lack of immunological tolerance in RA represents the first step toward the development of autoimmunity. Susceptible individuals, under the influence of environmental factors, such as tobacco smoke, and silica exposure, develop autoimmune phenomena that result in the presence of autoantibodies. HLA and non-HLA haplotypes play a major role in determining the development of specific autoantibodies differentiating anti-citrullinated antibodies (ACPA)-positive and negative RA patients. Rheumatoid factor (RF) and ACPA are the serological markers for RA, and during the preclinical immunological phase, autoantibody titers increase with a progressive spread of ACPA antigens repertoire. The presence of ACPA represents an independent risk factor for developing RA in patients with undifferentiated arthritis or arthralgia. Moreover, anti-CarP antibodies have been identified in patients with RA as well as in individuals before the onset of clinical symptoms of RA. Several autoantibodies mainly targeting post-translational modified proteins have been investigated as possible biomarkers to improve the early diagnosis, prognosis and response to therapy in RA patients. Psoriatic arthritis (PsA) is distinguished from RA by infrequent positivity for RF and ACPA, together with other distinctive clinical features. Actually, specific autoantibodies have not been described. Recently, anti-CarP antibodies have been reported in sera from PsA patients with active disease. Further investigations on autoantibodies showing high specificity and sensibility as well as relevant correlation with disease severity, progression, and response to therapy are awaited in inflammatory arthritides.

The interplay between inflammation and metabolism in rheumatoid arthritis

Rheumatoid arthritis (RA) is a chronic autoimmune disease characterized by extensive synovitis resulting in erosions of articular cartilage and marginal bone that lead to joint destruction. The autoimmune process in RA depends on the activation of immune cells, which use intracellular kinases to respond to external stimuli such as cytokines, immune complexes, and antigens. An intricate cytokine network participates in inflammation and in perpetuation of disease by positive feedback loops promoting systemic disorder. The widespread systemic effects mediated by pro-inflammatory cytokines in RA impact on metabolism and in particular in lymphocyte metabolism. Moreover, RA pathobiology seems to share some common pathways with atherosclerosis, including endothelial dysfunction that is related to underlying chronic inflammation. The extent of the metabolic changes and the types of metabolites seen may be good markers of cytokine-mediated inflammatory processes in RA. Altered metabolic fingerprints may be useful in predicting the development of RA in patients with early arthritis as well as in the evaluation of the treatment response. Evidence supports the role of metabolomic analysis as a novel and nontargeted approach for identifying potential biomarkers and for improving the clinical and therapeutical management of patients with chronic inflammatory diseases. Here, we review the metabolic changes occurring in the pathogenesis of RA as well as the implication of the metabolic features in the treatment response.

Role of IL-23 in the pathogenesis of psoriasis: a novel potential therapeutic target?

Introduction: Psoriasis is a chronic inflammatory skin disorder determined by the activation of several immune cells and resident tissue cells. Various cytokines mediate inflammatory signals, including IL-23, which is an important factor involved in the differentiation of T helper (Th17) cells. Areas covered: Increasing evidence suggests that IL-23 is a central cytokine to the pathogenesis of psoriasis. An overview on both experimental and human data will be reported in order to support the hypothesis of a key pathogenic role of IL-23/Th17 axis. Expert opinion: Targeting IL-23 might be a more selective, valid and effective therapeutic approach, which, potentially, may show important advantages in terms of long-term efficacy and safety in the treatment of psoriasis.

IL-21 in the pathogenesis and treatment of skin diseases

Interleukin-21 (IL-21) is a potent immunomodulatory cytokine, with pleiotropic effects on both innate and adaptive immune responses. These actions include positive effects, such as enhanced proliferation of lymphoid cells, increased cytotoxicity of CD8(+) T cells and natural killer cells, and differentiation of B cells into plasma cells. IL-21 is also produced by Th17 cells and is a critical regulator of Th17 development. IL-21 has potent antitumor activity, but is also associated with the development of autoimmune disease. Many of these activities are critically involved in the pathogenesis of several skin diseases such as psoriasis, atopic dermatitis, lupus erythematosus, and melanoma. Here we review recent advancements on the understanding of the role of IL-21 in skin diseases and how this knowledge can be translated into innovative therapeutic approaches.