The aim of our study was to analyse the serum interleukin-6 (IL-6), tumour necrosis factor-α (TNF-α), interleukin-1β (IL-1β) and interferon-γ(IFN-γ) levels in patients with AS and their relationship with disease activity. An ELISA test was used to analyse serum cytokine (IL-6, TNF-α, IL-1β and IFN-γ) levels in 69 patients with AS. Results were compared with those from 43 patients with RA and 36 patients with non-inflammatory back pain. The relationship between serum concentrations of the different cytokines and parameters of disease activity and severity in AS patients was also evaluated. IL-6 and TNF-α serum levels, but not IL-1β and IFN-γ, were significantly higher in AS than in NIBP. However, patients with RA showed higher serum levels of IL-6, TNF-α and IFN-γ than both AS and NIBP patients. In AS, IL-6 correlated with clinical parameters of disease activity with significant correlation being observed with laboratory parameters of inflammation such as ESR, CRP, platelet count and clinical parameters of severity such as vertebral mobility. TNF-α did not correlate with laboratory or clinical parameters of activity. Macrophagic cytokines (TNF-α and IL-6), are increased in AS patients and IL-6 closely correlated with the activity of the disease.

Objective: A double blind, randomised, placebo controlled study to evaluate the safety and efficacy of etanercept to treat adult patients with ankylosing spondylitis (AS). Methods: Adult patients with AS at 14 European sites were randomly assigned to 25 mg injections of etanercept or placebo twice weekly for 12 weeks. The primary efficacy end point was an improvement of at least 20% in patient reported symptoms, based on the multicomponent Assessments in Ankylosing Spondylitis (ASAS) response criteria (ASAS 20). Secondary end points included ASAS 50 and ASAS 70 responses and improved scores on individual components of ASAS, the Bath Ankylosing Spondylitis Disease Activity Index (BASDAI), acute phase reactants, and spinal mobility tests. Safety was evaluated during scheduled visits. Results: Of 84 patients enrolled, 45 received etanercept and 39 received placebo. Significantly more etanercept patients than placebo patients responded at the ASAS 20 level as early as week 2, and sustained differences were evident up to week 12. Significantly more etanercept patients reported ASAS 50 responses at all times and ASAS 70 responses at weeks 2, 4, and 8; reported lower composite and fatigue BASDAI scores; had lower acute phase reactant levels; and had improved spinal flexion. Etanercept was well tolerated. Most adverse events were mild to moderate; the only between-group difference was injection site reactions, which occurred significantly more often in etanercept patients. Conclusions: Etanercept is a well tolerated and effective treatment for reducing clinical symptoms and signs of AS.

Objectives: To characterise RA in a sample of Spanish patients by estimating mean clinical activity, functional ability, and radiological damage, and current and cumulative prevalence of extra-articular manifestations. Methods: Cross sectional analysis of a cohort of patients with RA randomly selected from the clinical databases of 34 centres. Standard definitions and measurements were used, and radiographs read centrally. Estimates and confidence intervals were adjusted to sampling. Results: Data were available for 788 patients. Extra-articular RA was present in 285 (36.2%) patients. Cumulative prevalence and 95% confidence intervals of extra-articular manifestations were estimated: nodules 24.5% (21.5 to 27.5), Sjögren’s syndrome 17.0% (14.4 to 19.6), atlantoaxial subluxation 12.1% (9.8 to 14.4), carpal tunnel syndrome 10.7% (7.8 to 13.6), interstitial lung disease 3.7% (2.4 to 5.0), serositis 2.5% (1.4 to 3.5), eye disease 2.5% (1.1 to 3.9), vasculitis 1.3% (0.5 to 2.1), amyloidosis 0.6% (0.1 to 1.2), and Felty’s syndrome 0.3% (<0.6). Mean (SD) activity/progression indexes were: DAS28-3 3.4 (1.2), HAQ 1.6 (0.4), Larsen score 54.7 (26.4). Less than 5% of the patients were in remission. 205 (72%) patients were receiving disease modifying antirheumatic drugs (DMARDs). Conclusion: Spanish patients with RA ever seen by a rheumatologist have, on average, a moderate degree of activity, despite widespread use of DMARDs. Measures of the degree of progression do not show a benign disease. The proportion of extra-articular manifestations in Spanish patients with RA is similar to that found in other Mediterranean populations, and lower than that reported in Anglo Saxon countries.

S100A9/S100A8 (calprotectin), a member of the S100 protein family, has been shown to play a pivotal role in innate immunity activation. Calprotectin plays a critical role in the pathogenesis of rheumatoid arthritis (RA), as it triggers chemotaxis, phagocyte migration and modulation of neutrophils and macrophages. Higher calprotectin levels have been found in synovial fluid, plasma, and serum from RA patients. Recent studies have demonstrated better correlations between serum or plasma calprotectin and composite inflammatory disease activity indexes than c-reactive protein (CRP) or the erythrocyte sedimentation rate (ESR). Calprotectin serum levels decreased after treatment, independently of the DMARD type or strategy. Calprotectin has shown the strongest correlations with other sensitive techniques to detect inflammation, such as ultrasound. Calprotectin independently predicts radiographic progression. However, its value as a biomarker of treatment response and flare after tapering is unclear. This update reviews the current understanding of calprotectin in RA and discusses possible applications as a biomarker in clinical practice.

OBJECTIVE To investigate possible differences in Th1 and Th2 cytokine mRNA expression in the synovial tissue (ST) of patients with rheumatoid arthritis (RA) and seronegative spondyloarthropathies (SpA) with diagnostic and/or pathogenic interest. METHODS Eleven RA patients and 14 SpA patients (10 with undifferentiated spondyloarthropathy (USpA), two with ankylosing spondylitis (AS) and two with psoriatic arthritis (PsA)) were included. Th1 (interferon γ, interleukin 2) and Th2 (interleukin 4, interleukin 5 and interleukin 10) cytokine mRNA levels from arthritic knee ST were quantified by using an optimised polymerase chain reaction method with a computerised analysis system. Protein levels of proinflammatory cytokines (interleukin 1, tumour necrosis factor α and interleukin 6) in synovial fluid were quantified with a specific ELISA test. RESULTS Th1 cytokines were detected in all of RA ST samples in contrast with 58% (interferon γ) and 71% (interleukin 2) of SpA samples. Th2 cytokines were expressed in 90% of RA ST samples, but the findings in SpA were interleukin 10 in 90%, interleukin 4 in 60% and interleukin 5 in 40% of ST samples. However, when the mRNA levels of each cytokine were quantified and corrected for T cell mRNA levels, only interferon γ levels were significantly higher in RA than in SpA (p<0.003). Thus, the Th1/Th2 cytokine ratio in RA was fivefold that of SpA. Synovial fluid interleukin 1β concentrations were higher in RA than in SpA (p<0.05); there were also higher synovial fluid levels of tumour necrosis factor α in RA than in SpA, but without statistical significance. CONCLUSION This study has detected both Th1 and Th2 cytokine gene expression in ST from RA and SpA patients. Synovium interferon γ mRNA levels and SF interleukin 1β protein levels were significantly higher in RA than in SpA, so reflecting the known proinflammatory activity of interferon γ through macrophage activation. Thus, the Th1 (interferon γ)/Th2 (interleukin 4) ratio is significantly higher in RA than in SpA ST. These data confirm previous studies on ST Th1/Th2 balance in RA and extend previous work in comparing ST RA with subgroups of SpA distinct of ReA.

Objective To analyze whether inflammatory disease activity plays a substantial role in the loss of bone mass observed in ankylosing spondylitis (AS) patients who have not yet developed ankylosis. Methods A longitudinal cohort study of 34 patients with early AS (duration <10 years) without ankylosis was conducted. The mean followup was 19 months. Loss of bone mass in defined regions of the lumbar spine and femoral neck was analyzed by dual x-ray absorptiometry. Patients were grouped according to biologic parameters of disease activity (erythrocyte sedimentation rate or C-reactive protein level). Group 1 consisted of 14 patients with active disease; group 2 comprised 20 patients with inactive disease. Serum levels of interleukin-6 (IL-6) and of hormones (sex, thyroid, and calciotropic), vertebral mobility (Schober test), daily physical activity, and treatment administered were recorded every 6 months for all patients. Results At the end of the followup period, patients with active AS showed a significant reduction in bone mass in the lumbar spine (mean 1.01 gm/cm² at study entry versus 0.961 gm/cm² at followup [P = 0.005]) and femoral neck (0.849 gm/cm² versus 0.821 gm/cm² [P = 0.015]), which represented losses of 5% and 3%, respectively. In contrast, no significant reduction in bone mass was observed in patients with inactive AS. As expected, serum IL-6 levels were significantly higher in patients with active AS than in those with inactive disease (mean ± SD 8.3 ± 9 pg/ml versus 2.8 ± 5 pg/ml [P = 0.008]). No significant differences were observed between the 2 groups in any of the other variables analyzed. Conclusion The observation that loss of bone mass in AS occurred only in patients with persistent active disease strongly suggests that inflammatory activity of the disease itself plays a major role in the pathophysiology of the early bone mineral disorders observed in these patients.