Pathological role of interleukin-6 in psoriatic arthritis

Changes in Inflammatory Cytokines in Responders and Non-Responders to TNFα Inhibitor and IL-17A Inhibitor: A Study Examining Psoriatic Arthritis Patients

This study aimed to examine the changes in biomarker levels in responders and non-responders to tumor necrosis factor alpha inhibitor (TNFi) and interleukin-17A inhibitor (IL-17Ai) in psoriatic arthritis (PsA) patients over a 4-month period after treatment initiation. A total of 68 PsA patients initiating either TNFi, IL-17Ai, or methotrexate treatment were included. Blood plasma and clinical outcome measures were collected adjacent to treatment initiation and after four months. A commercially available multiplex immunoassay was included to evaluate 54 biomarkers. Mean changes were used to evaluate change over time. A statistically significant decrease in pro-inflammatory cytokines IL-6 (log-transformed mean change -0.97, 95%CI -4.30; 2.37, [p = 0.032]) and an increase in anti-inflammatory IL-10 (0.38, 95%CI 1.74; 2.50 [p = 0.010]) were seen in TNFi responders. Meanwhile, a statistically significant increase in the target cytokine IL-17A was seen in both IL-17Ai responders (2.49, 95%CI -1.84; 6.85 [p = 0.031]) and non-responders (2.48, 95%CI -1.46; 6.41 [p = 0.001]). This study demonstrated differing changes in cytokine levels when comparing treatment responders and non-responders, highlighting the need to improve the understanding of the different immune response mechanisms explaining different responses to medical treatment in PsA patients.

The Combination of IL-6, PLR and Nail Psoriasis: Screen for the Early Diagnosis of Psoriatic Arthritis

Background

Early screening or timely prediction of psoriatic arthritis (PsA) are crucial. The study aimed to compare the clinical characteristics, cytokines and inflammation index between plaque psoriasis and PsA to explore their values in the early diagnosis of PsA.

Methods

This was a case-control study in a single center from January 2021 to February 2023. The differences in clinical characteristics and laboratory examinations between PsA and plaque psoriasis were conducted. Patients with rheumatoid arthritis (RA) were used as a positive control. The correlation between variables were analyzed and multivariable logistic regression were performed by using the 10-fold cross-validation to find independently risk factors of plaque psoriasis that are developing PsA.

Results

A total of 109 patients with plaque psoriasis (without joint damage), 47 patients with PsA and 41 patients with RA were enrolled in this study. The study found that the proportion of patients with elevated serum IL-6 levels, as well as the value of platelet to lymphocyte ratio (PLR) and systemic immune-inflammation index (SII), were significantly higher in patients with PsA and early PsA (PsA course ≤2 years) compared to those with plaque psoriasis (p<0.05). After adjusting for age, gender, severity of skin lesions, and comorbidities (diabetes, hypertension, hyperlipidemia, hyperuricemia, and overweight/obesity), the study identified nail psoriasis (OR=4.35, 95% CI 1.67-11.29, p<0.002), elevated serum IL-6 (OR=6.78, 95% CI 2.34-19.67, p<0.001), and PLR (OR=8.37, 95% CI 2.97-23.61, p<0.001) as independent risk factors for PsA. A multivariable logistic regression analysis employing 10-fold cross-validation assessing the predictive association between the diagnosis of early PsA and the combination of IL-6, PLR, and nail psoriasis demonstrated that the area under the curve (AUC) was 0.84 (95% CI 0.77-0.90) and the F1-score was 0.67 (95% CI 0.54-0.80).

Conclusion

The combination of elevated serum IL-6, PLR, and nail psoriasis can help to predict and screen the early stage of PsA.

Psoriatic disease and non-alcoholic fatty liver disease shared pathogenesis review

Psoriatic disease (PD) and non-alcoholic fatty liver disease (NAFLD) potentially share disease pathways given the numerous inflammatory pathways involved in both diseases and a higher prevalence of NAFLD in PD patients.  Metabolic syndrome and obesity are a key link between the two diseases, but even when controlling for this, associations between both diseases are still seen. Therapeutics that impact metabolic or inflammatory pathways may be impactful in both PD and NAFLD. In this review, we describe common inflammatory pathways contributing to both PD and NAFLD and critically review the potential impact of treatments for and on both diseases.

Cytokine Signatures in Psoriatic Arthritis Patients Indicate Different Phenotypic Traits Comparing Responders and Non-Responders of IL-17A and TNFα Inhibitors

This study aimed to explore the dynamic interactions between 32 cytokines and biomarkers in Psoriatic Arthritis (PsA) patients to compare cytokine signatures of treatment responders and non-responders. Biomarkers were measured before and after four months of treatment in 39 PsA patients initiating either Tumor Necrosis Factor alpha inhibitor (TNFi) or Interleukin-17A inhibitor (IL-17Ai). Response to treatment was defined by the composite measure, Disease Activity in Psoriatic Arthritis (DAPSA). A two-component principal component analysis (PCA) was implemented to describe cytokine signatures comparing DAPSA50 responders and non-responders. The cytokine signature of TNFi responders was driven by the correlated cytokines interferon γ (IFNγ) and IL-6, additionally associated with IL-12/IL-23p40, TNFα, and CRP, while the cytokine signature of TNFi non-responders was driven by the correlated cytokines IL-15, IL-8, and IFNγ. IL-17Ai responders were characterized by contributions of strongly correlated Th17 inflammatory cytokines, IL-17A, IL-12/IL-23p40, IL-22 to the cytokine signature, whereas IL-17A and IL-12/IL-23p40 did not demonstrate significant contribution in IL-17Ai non-responders. Based on PCA results it was possible to differentiate DAPSA50 responders and non-responders to treatment, endorsing additional examination of cytokine interaction models in PsA patients and supporting further PsA patient immune stratification to improve individualized treatment of PsA patients.

Mendelian Randomization Studies in Psoriasis and Psoriatic Arthritis: A Systematic Review

Psoriasis (PSO) and psoriatic arthritis (PSA) are inflammatory diseases with complex genetic and environmental contributions. Although studies have identified environmental and clinical associations with PSO/PSA, causality is difficult to establish. Mendelian randomization (MR) employs the random assortment of genetic alleles at birth to evaluate the causal impact of exposures. We systematically reviewed 27 MR studies in PSO/PSA examining health behaviors, comorbidities, and biomarkers. Exposures, including smoking, obesity, cardiovascular disease, and Crohn's disease, were causal for PSO and PSA, whereas PSO was causally associated with several comorbidities. These findings provide insights that can guide preventive counseling and precision medicine.

Multiple Cytokine Analysis of Th1/Th2/Th9/Th17/Th22/Treg Cytokine Pathway for Individual Immune Profile Assessment in Patients with Psoriasis

BACKGROUND Psoriasis is an autoimmune and autoinflammatory disorder that has a significant impact on patient quality of life. The aim of the study was to assess the immune profiles of patients with psoriasis with multiple cytokine analysis. MATERIAL AND METHODS Fifty-two male psoriatic patients and 24 healthy male volunteers were recruited. Granulocyte-macrophage colony-stimulating factor (GM-CSF), interferon gamma (IFN-gamma), interleukin (IL)-1 beta, IL-2, Il-4, IL-5, IL-6, IL-9, IL-10, IL-12p70, IL-13, IL-17A, IL-18, IL-21, IL-22, IL-23, IL-27, and tumor necrosis factor (TNF)-alpha were measured in patients' serum with a Th1/Th2/Th9/Th17/Th22/Treg Cytokine 18-Plex Human ProcartaPlex Panel, based on Luminex xMAP technology. RESULTS The median fluorescence intensities of serum GM-CSF, IL-2, IL-5, IL-10, IL-13, IL-17A, IL-21, and IL-22 were not intensive enough to calculate the cytokine concentration. We observed elevated levels of IL-6 (P=0.001) and IL-9 (P=0.003) in patients, compared with the control group. The levels of IL-1beta (P=0.008) and IL-27 (P=0.006) were decreased. In patients with psoriatic arthritis, we noticed a decreased level of IL-9 compared with that in patients without arthritis (P=0.034). The levels of IL-12 (P<0.05) and IL-18 (P<0.05) correlated positively with the Psoriasis Area and Severity Index. We found negative correlations of IL-9 (P<0.05), IL-12 (P<0.05), and IL-23 (P<0.05) with the age of psoriatic patients; IL-12 (P<0.05) and IL-23 (P<0.05) with psoriasis duration; and IL-6 (P<0.05) and IL-9 (P<0.05) with the Nail Psoriasis Severity Index. CONCLUSIONS Multiple cytokine analysis seems to be an important form of individual immune profile assessment before treatment selection.

The effect of exercise on cytokines: implications for musculoskeletal health: a narrative review

The physiological effects of physical exercise are ubiquitously reported as beneficial to the cardiovascular and musculoskeletal systems. Exercise is widely promoted by medical professionals to aid both physical and emotional wellbeing; however, mechanisms through which this is achieved are less well understood. Despite numerous beneficial attributes, certain types of exercise can inflict significant significant physiological stress. Several studies document a key relationship between exercise and immune activation. Activation of the innate immune system occurs in response to exercise and it is proposed this is largely mediated by cytokine signalling. Cytokines are typically classified according to their inflammatory properties and evidence has shown that cytokines expressed in response to exercise are diverse and may act to propagate, modulate or mitigate inflammation in musculoskeletal health. The review summarizes the existing literature on the relationship between exercise and the immune system with emphasis on how exercise-induced cytokine expression modulates inflammation and the immune response.

The Role of Interleukins in the Pathogenesis of Dermatological Immune-Mediated Diseases

Autoimmune inflammatory diseases are primarily characterized by deregulated expression of cytokines, which drive pathogenesis of these diseases. A number of approved and experimental therapies utilize monoclonal antibodies against cytokine proteins. Cytokines can be classified into different families including the interleukins, which are secreted and act on leukocytes, the tumor necrosis factor (TNF) family, as well as chemokine proteins. In this review article, we focus on the interleukin family of cytokines, of which 39 members have been identified to this date. We outline the role of each of these interleukins in the immune system, and various dermatological inflammatory diseases with a focused discussion on the pathogenesis of psoriasis and atopic dermatitis. In addition, we describe the roles of various interleukins in psychiatric, cardiovascular, and gastrointestinal comorbidities. Finally, we review clinical efficacy and safety data from emerging late-phase anti-interleukin therapies under development for psoriasis and atopic dermatitis. Collectively, additional fundamental and clinical research remains necessary to fully elucidate the roles of various interleukin proteins in the pathogenesis of inflammatory dermatologic diseases, and treatment outcomes in patients.

Development and In Vitro/In Vivo Evaluation of pH-Sensitive Polymeric Nanoparticles Loaded Hydrogel for the Management of Psoriasis

Methotrexate (MTX), the gold standard against psoriasis, poses severe problems when administered systemically viz increased toxicity, poor solubility and adverse reactions. Hence, a topical formulation of MTX for the management of psoriasis can be an effective approach. The present study aimed to develop an MTX based nanoparticle-loaded chitosan hydrogel for evaluating its potential efficacy in an imiquimod-induced psoriatic mice model. MTX-NPs loaded hydrogel was prepared and optimized using the o/w emulsion solvent evaporation method. Particle size, zeta potential, entrapment efficiency, in vitro drug release, ex vivo permeation, skin irritation and deposition studies were performed. Psoriatic Area and Severity Index (PASI) score/histopathological examinations were conducted to check the antipsoriatic potential of MTX-NPs loaded hydrogel using an imiquimod (IMQ)-induced psoriatic model. Optimized MTX-NPs showed a particle size of 256.4 ± 2.17 nm and encapsulation efficiency of 86 ± 0.03%. MTX-NPs loaded hydrogel displayed a 73 ± 1.21% sustained drug release in 48 h. Ex vivo permeation study showed only 19.95 ± 1.04 µg/cm2 of drug permeated though skin in 24 h, while epidermis retained 81.33% of the drug. A significant decrease in PASI score with improvement to normalcy of mice skin was observed. The developed MTX-NPs hydrogel displayed negligible signs of mild hyperkeratosis and parakeratosis, while histopathological studies showed healing signs of mice skin. So, the MTX-NPs loaded hydrogel can be a promising delivery system against psoriasis.

Genetic Associations Between IL-6 and the Development of Autoimmune Arthritis Are Gender-Specific

Objectives

To find out the genetic association between IL6 and autoimmune arthritis.

Methods

We performed a two-sample Mendelian randomization (MR) study using multiple genome-wide association studies (GWAS) datasets. Furthermore, a sex-stratified MR study was performed to identify sexual dimorphism in the association between IL6 and autoimmune arthritis. Then, LocusZoom plots were displayed based on the IL6R gene region to present evidence of genetic colocalization between diseases.

Results

The MR result denoted a genetic association between the increased level of IL-6 signaling and risk of RA (β=0.325, 95%CI 0.088, 0.561, p=7.08E-03) and AS (β=1.240, 95%CI 0.495, 1.980, p=1.1E-03). Accordingly, sIL6R was found to have negatively correlation with the onset of RA (β=-0.020, 95%CI -0.0320, -0.008, p=1.18E-03) and AS (β=-0.125, 95%CI -0.177, -0.073, p=2.29E-06). However, no genetic association between IL6/sIL6R and PsA was detected. The gender-stratified MR analysis showed that IL6 was associated with AS in the male population, with RA in the female population, and with PsA in the male population. Additionally, ADAR, a gene identified by a sensitive test, could be the reason for the nonsignificant association between IL6 and PsA in a pooled population.

Conclusion

Our findings showed that the overactive IL6 signal pathway led to autoimmune arthritis, especially in RA and AS. Sexual difference was also observed in IL6-intermediate susceptibility to autoimmune arthritis.

Tocilizumab and its usage for skin diseases

The monoclonal anti-IL6 receptor antibody called Tocilizumab is widely used by rheumatologists for joint diseases. Its application in dermatology has mainly concerned scleroderma and Systemic Sclerosis in the last years. The most varied skin diseases treated with tocilizumab, such as psoriasis, psoriatic arthritis, Behcet's Syndrome, Lupus, and the already mentioned scleroderma up to multi-organ syndromes with skin involvement will be discussed. At the same time, there have been several side reactions to the drug involving the skin forcing careful skin monitoring during treatment. Despite the evidence currently available in the appropriate literature, there is no formal recommendation for any of these diseases to use Tocilizumab for therapeutic purposes. The aim of this review was to collect all the main evidence on the use and involvement of the drug in dermatological practice in order to stimulate further research or hypothesize on possible therapeutic options.

Psoriatic arthritis and depressive symptoms: does systemic inflammation play a role?

OBJECTIVES

Depression is commonly associated with psoriatic arthritis (PsA), but its risk factors in these patients are largely unrecognized. Pro-inflammatory cytokines involved in the pathogenesis of PsA have been associated with depression in patients without autoimmune diseases. The aim of this study was to establish whether PsA patients with and without depressive symptoms differed for general or clinical variables and serum cytokines milieu.

METHODS

One hundred and fifty consecutive patients with PsA were screened for depressive symptoms with Hospital Anxiety and Depression Scale (HADS-D). Patients with and without depressive symptoms were compared according to the prevalence of general risk factors for depression, comorbidities, PsA features and serum IL-6, TNF-α, and IL-17A.

RESULTS

Fifty-eight patient (38.7%) had a depressive mood. Depressive symptoms were associated with female sex (p = 0.03) and current smoking (p = 0.05). Patients with and without depressive symptoms did not differ for general risk factors for depression and comorbidities. Depressed patients had more frequently psoriatic nail disease (p = 0.02) and significant physical disability (HAQ-DI ≥ 0.5) (p < 0.01) and were more frequently in moderate or high disease activity according to DAPSA score (p = 0.01). Depressed patients had higher serum IL-6 (p < 0.01) and comparable serum IL-17A and TNF-α. A cutoff of 2.27 pg/ml of serum IL-6 had the best ability to predict an HADS-D ≥ 8 (AUC 0.666 ± 0.044; p < 0.01). Multivariate logistic regression analysis confirmed that serum IL-6 ≥ 2.27 pg/ml was independently associated with depressive symptoms (OR 3.5; CI 1.6-7.8; p < 0.01).

CONCLUSIONS

Higher serum Il-6 is associated with depressive symptoms. This association suggests a direct role of systemic inflammation in the modulation of mood in PsA patients. Key Points • High PsA disease activity and physical disability are associated with depression. • Higher serum levels of IL-6 are independently associated with depression in PsA. • IL-6 might play a direct role in the development of depression in PsA patients.

An Update for the Clinician on Biologics for the Treatment of Psoriatic Arthritis

Psoriatic arthritis (PsA) is a chronic inflammatory arthropathy typically associated with psoriasis (PsO). The pathogenesis is strictly related to the association among the presence of genetic risk alleles and innate and acquired immune response with dramatic consequences on bone remodeling. Clinically, PsA patients may present heterogenicity of articular and periarticular manifestations that may be associated with the presence of comorbidities making treatment decision challenging in patients management. The identification of patient-targeted therapies is still a critical issue. Actually, several biological and synthetic drugs are promising in terms of efficacy and safety profile. National and international treatment recommendations support clinicians in the decision of the best treatment, although they may have limits basically related to updates and different outcomes included in the clinical studies evaluated. The aim of this narrative review is therefore to give guidance for clinicians for PsA patients treatment. For this purpose, we evaluated evidence on biological therapies efficacy used for PsA treatment. Specifically, we reviewed data on biological therapies, Janus kinases (JAK) inhibitors, and drugs with a new mechanism of action that are part of the treatment pipeline. The concept of "switching" and "swapping" is also described, as well as data concerning special populations such as pregnant women and elderly patients.

The evaluation of cytokines to help establish diagnosis and guide treatment of autoinflammatory and autoimmune diseases

Our knowledge of the role of cytokines in pathologic conditions has increased considerably with the emergence of molecular and genetic studies, particularly in the case of autoinflammatory monogenic diseases. Many rare disorders, considered orphan until recently, are directly related to abnormal gene regulation, and the treatment with biologic agents (biologics) targeting cytokine receptors, intracellular signaling or specific cytokines improve the symptoms of an increasing number of chronic inflammatory diseases. As it is currently impossible to systematically conduct genetic studies for all patients with autoinflammatory and autoimmune diseases, the evaluation of cytokines can be seen as a simple, less time consuming, and less expensive alternative. This approach could be especially useful when the diagnosis of syndromes of diseases of unknown etiology remains problematic. The evaluation of cytokines could also help avoid the current trial-and-error approach, which has the disadvantages of exposing patients to ineffective drugs with possible unnecessary side effects and permanent organ damages. In this review, we discuss the various possibilities, as well as the limitations of evaluating the cytokine profiles of patients suffering from autoinflammatory and autoimmune diseases, with methods such as direct detection of cytokines in the plasma/serum or following ex vivo stimulation of PBMCs leading to the production of their cytokine secretome. The patients' secretome, combined with biomarkers ranging from genetic and epigenetic analyses to immunologic biomarkers, may help not only the diagnosis but also guide the choice of biologics for more efficient and rapid treatments.

Serum concentration of interleukin 6 is related to inflammation and dyslipidemia in patients with psoriasis

INTRODUCTION

Patients with psoriasis and psoriatic arthritis (PsA) have metabolic disturbances, which may be due to chronic inflammation.

AIM

Because interleukin-6 (IL-6) regulates both metabolic and inflammatory processes, we evaluated IL-6 as a potential marker of inflammation and metabolic disturbances in psoriasis.

MATERIAL AND METHODS

This study involved 93 patients with psoriasis, including 31 patients with concurrent PsA. We investigated whether serum markers of lipid metabolism and inflammation, including IL-6, were related to each other and to disease activity.

RESULTS

We found that concurrent PsA was associated with higher serum concentrations of total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), and IL-6. In patients with psoriasis alone, the IL-6 serum concentration correlated positively with the concentrations of TC and LDL-c and with erythrocyte sedimentation rates (ESRs). Moreover, IL-6 concentrations tended to correlate positively with the percentage of the body area affected by psoriatic lesions. Among all patients, those with normal blood lipids had lower ESRs and IL-6 concentrations than patients with abnormal blood lipids. A logistic regression model showed that PsA, Psoriasis Area Severity Index (PASI), and ESR were significant predictors of the serum IL-6 concentration.

CONCLUSIONS

Interleukin-6 may be an indicator of inflammatory activity in psoriasis. Moreover, IL-6 may be related to lipid abnormalities in patients with this disease.

Interleukin-6 in juvenile idiopathic arthritis

Juvenile idiopathic arthritis (JIA) is a chronic childhood arthritis. Its pathogenesis is very complicated, with the involvement of not only immune cells but various types of parenchymal cells, and is affected by both genetic and environmental predispositions. The clinical spectrum from inflammation to related conditions is largely mediated by cytokines including interleukin (IL)-6. Fluctuations in IL-6 and its related molecules can modulate the pathogenesis and the clinical presentation positively or negatively. The recent clinical impact of IL-6 blockade on JIA has begun a therapeutic paradigm shift. This review describes the characteristics of JIA, mainly focused on IL-6 with the current therapeutic perspective.

Biologic Agent-Associated Cutaneous Adverse Events: A Single Center Experience

Biologic agents are regarded as an effective treatment for a variety of autoimmune diseases. These drugs have an acceptable safety and tolerability profile, although an increasing number of autoimmune conditions have been reported with their use. Additionally, a variety of cutaneous diseases have been associated with their use. Here we report our experience of adverse cutaneous events with the use of biologic agents. An alternative explanation for patients presenting with adverse cutaneous events including drug interactions must be carefully investigated.

Altered Bone Remodeling in Psoriatic Disease: New Insights and Future Directions

Psoriatic arthritis (PsA) is an inflammatory rheumatic disorder that occurs in patients with psoriasis and predominantly affects musculoskeletal structures, skin, and nails. The etiology of PsA is not well understood but evidence supports an interplay of genetic, immunologic, and environmental factors which promote pathological bone remodeling and joint damage in PsA. Localized and systemic bone loss due to increased activity of osteoclasts is well established in PsA based on animal models and translational studies. In contrast, the mechanisms responsible for pathological bone remodeling in PsA remain enigmatic although new candidate molecules and pathways have been identified. Recent reports have revealed novel findings related to bone erosion and pathologic bone formation in PsA. Many associated risk factors and contributing molecular mechanisms have also been identified. In this review, we discuss new developments in the field, point out unresolved questions regarding the pathogenetic origins of the wide array of bone phenotypes in PsA, and discuss new directions for investigation.

Beyond TNF Inhibitors: New Pathways and Emerging Treatments for Psoriatic Arthritis

Psoriatic arthritis (PsA) is a chronic inflammatory disease characterized by psoriasis, synovitis, enthesitis, spondylitis and association with other extra-articular manifestations. Chronic inflammation of involved tissues possibly leads to structural damage and to a reduction in function and quality of life. The treatment of PsA dramatically changed with the introduction of anti-tumor necrosis factor (TNF)-α drugs, which have been shown to reduce the symptoms and signs of the disease, and slow radiographic progression. However, some patients do not respond to anti-TNFα or have a loss of response. Recently, the discovery of new pathogenic mechanisms have made possible the development of new drugs that target pro-inflammatory cytokines, such as interleukin (IL)-12, IL-23 and IL-17, or interfere with cellular pathways involved in skin, joint and entheseal inflammation. New molecules, namely ustekinumab, secukinumab, and apremilast have shown efficacy and safety over the various components of the disease in randomized clinical trials. These drugs have been recently approved for the treatment of PsA and included in new treatment recommendations. Other molecules are currently being tested in phase III clinical trials and are potential new treatment options for PsA. The aim of this review is to update the new pathways involved in the development of the disease and the emerging treatments for PsA beyond TNFα inhibition.

Subcutaneous formulation of tocilizumab for treatment of rheumatoid arthritis

Tocilizumab (TCZ) is a humanized monoclonal antibody against the IL-6 receptor that is indicated for the treatment of rheumatoid arthritis (RA), juvenile idiopathic arthritis and Castleman's disease. TCZ was developed as an intravenous (IV) formulation and approved for RA treatment in Japan (2008), the EU (2009) and the USA (2010). Recently, a subcutaneous (SC) formulation of TCZ was developed and approved for RA treatment. Efficacy and safety of TCZ-SC were reported through three randomized trials: MUSASHI, SUMMACTA and BREVACTA. Clinical efficacy and overall safety of TCZ-SC was comparable to that of TCZ-IV. However TCZ-SC, which is provided in a fixed dose, the efficacy was affected by patient weight. The frequencies of injection site reactions and anti-TCZ antibodies were increased with TCZ-SC compared with TCZ-IV, although differences were minimal and at a negligible level for daily clinical practice. This review highlights the potential of TCZ-SC in RA treatment.

Tocilizumab-induced psoriasiform rash in rheumatoid arthritis

Tocilizumab (TCZ) is a humanized monoclonal antibody against the interleukin-6 (IL-6) receptor and has been approved for the treatment of rheumatoid arthritis (RA) patients who have had an inadequate response to previous biological therapies. Psoriasiform skin lesions, especially palmoplantar pustulosis lesions, are well described following anti-tumour necrosis factor therapy. We describe a 79-year-old woman with rheumatoid factor-positive, anti-citrullinated protein antibody-positive erosive RA, who developed a psoriasiform palmoplantar pustulosis reaction following treatment with TCZ therapy (IL-6 receptor). The rash showed histological features compatible with psoriasis and disappeared following discontinuation of TCZ.

Differences in bone structure between rheumatoid arthritis and psoriatic arthritis patients relative to autoantibody positivity

OBJECTIVE

To investigate whether trabecular and cortical bone structure differ between patients with rheumatoid arthritis (RA) and psoriatic arthritis (PsA). So far, no study has performed a detailed comparative analysis of bone structure in patients with RA and PsA.

METHODS

110 patients (60 RA, 50 PsA) received high-resolution peripheral quantitative CT of the distal radius. Demographic and disease-specific parameters including anti-rheumatic treatment, bone erosion status and previous fractures were recorded.

RESULTS

RA and PsA patients were comparable in age, gender, body mass index, disease duration, disease activity, functional status, antirheumatic treatment and bone erosion status. No significant differences were found for volumetric bone mineral density (BMD), including total BMD (300±77 vs 316±62 mgHA/cm(3)), trabecular BMD (152±46 vs 165±40 mgHA/cm(3)) and cortical BMD (787±113 vs 818±76 mgHA/cm(3)) when comparing RA patients to PsA patients, respectively. However, in contrast to seronegative RA, seropositive RA showed significantly reduced trabecular BMD (p=0.007), bone volume per tissue volume (p=0.007) and trabecular number (p=0.044), as well as a strong trend towards higher trabecular inhomogeneity compared to PsA patients. In the regression analysis, higher age, female gender and presence of autoantibodies were independently associated with trabecular bone loss.

CONCLUSIONS

Seropositive RA exhibits more profound changes in trabecular bone architecture than seronegative RA or PsA. The data support the concept that seropositive RA is a disease entity that is distinct from seronegative RA and PsA.