Host immune genetic variations influence the risk of developing acute myeloid leukaemia: results from the NuCLEAR consortium.

The purpose of this study was to conduct a two-stage case control association study including 654 acute myeloid leukaemia (AML) patients and 3477 controls ascertained through the NuCLEAR consortium to evaluate the effect of 27 immune-related single nucleotide polymorphisms (SNPs) on AML risk. In a pooled analysis of cohort studies, we found that carriers of the IL13rs1295686A/A genotype had an increased risk of AML (PCorr = 0.0144) whereas carriers of the VEGFArs25648T allele had a decreased risk of developing the disease (PCorr = 0.00086). In addition, we found an association of the IL8rs2227307 SNP with a decreased risk of developing AML that remained marginally significant after multiple testing (PCorr = 0.072). Functional experiments suggested that the effect of the IL13rs1295686 SNP on AML risk might be explained by its role in regulating IL1Ra secretion that modulates AML blast proliferation. Likewise, the protective effect of the IL8rs2227307 SNP might be mediated by TLR2-mediated immune responses that affect AML blast viability, proliferation and chemorresistance. Despite the potential interest of these results, additional functional studies are still warranted to unravel the mechanisms by which these variants modulate the risk of AML. These findings suggested that IL13, VEGFA and IL8 SNPs play a role in modulating AML risk.

2016 update of the Portuguese recommendations for the use of biological therapies in children and adolescents with Juvenile Idiopathic Arthritis.

OBJECTIVE: To provide evidence-based guidance for the rational and safe prescription of biological therapies in children and adolescents with juvenile idiopathic arthritis (JIAs) considering the latest available evidence and the new licensed biologics. METHODS: Rheumatologists and Pediatricians with expertise in Pediatric Rheumatology updated the recommendations endorsed by the Portuguese Society of Rheumatology and the Portuguese Society of Pediatrics based on published evidence and expert opinion. The level of agreement with final propositions was voted using an online survey. RESULTS: In total, 20 recommendations to guide the use of biological therapy in children and adolescents with JIAs are issued, comprising 4 general principles and 16 specific recommendations. A consensus was achieved regarding the eligibility and response criteria, maintenance of biological therapy, and procedures in case of non-response, for each JIA category. Specific recommendations concerning safety procedures were also updated. CONCLUSIONS: These recommendations take into account the specificities of each JIA category and are intended to continuously improve the management of JIA patients.

A diagnosis of disseminated tuberculosis based on knee arthroscopic guided synovial biopsy in the context of monoarthritis.

Accounting for 2.2-4.7% of all tuberculosis cases in Europe and USA and around 10-15% of extra-pulmonary tuberculosis cases, osteoarticular tuberculosis tends to be chronic, slowly progressive and destructive. We report the case of an 81-year-old male with 3 weeks of progressively worsening pain, swelling and limited range of motion of the left knee. A knee arthroscopy was performed for synovial biopsy at our department revealing diffuse synovitis with scarce villi formation. The positive polymerase chain reaction assay for Mycobacterium tuberculosis in the synovial tissue allowed the establishment of the diagnosis and synovium histology showed caseating granulomas. A lengthy delay between first symptoms of osteoarticular tuberculosis and the beginning of treatment has been reported. A high index of suspicion, synovial membrane biopsy and appropriate microbiologic testing are fundamental to avoid a delay in diagnosis.

Pharmacology of biosimilar candidate drugs in rheumatology: a literature review.

OBJECTIVE: To review current evidence concerning pharmacology of biosimilar candidates to be used in rheumatology. METHODS: A PubMed search up to August 2013 was performed using relevant search terms to include all studies assessing pharmacological properties of biosimilar candidates to be used in rheumatology. Data on study characteristics, type of intervention, pharmacokinetics (PK), pharmacodynamics (PD) and bioequivalence ratios was extracted. RESULTS: Of 280 articles screened, 5 fulfilled our inclusion criteria. Two trials, PLANETAS and PLANETRA, compared CT-P13 and infliximab in patients with active ankylosing spondylitis and rheumatoid arthritis, respectively. PK bioequivalence was demonstrated in the phase 1 PLANETAS trial by highly comparable area under the curve (AUC) and maximum drug concentrations (Cmax), whose geometric mean ratios fell between the accepted bioequivalence range of 80-125%. Equivalence in efficacy and safety was demonstrated in the phase 3 PLANETRA trial. Two phase 1 trials comparing etanercept biosimilar candidates TuNEX and HD203 in healthy volunteers showed a high degree of similarity in AUC and Cmax, with respective geometric mean ratios between PK bioequivalence range. The last included trial referred to GP2013, a rituximab biosimilar candidate, which demonstrated PK and PD bioequivalence to reference product in three different dosing regimens in cynomolgus monkeys. CONCLUSION: Infliximab, etanercept and rituximab biosimilar candidates have demonstrated PK bioequivalence in the trials included in this review. CT-P13 has recently been approved for use in the European market and the remaining biosimilar candidates are currently being tested in patients with rheumatoid arthritis.

Effective treatment of rat adjuvant-induced arthritis by celastrol.

We have previously reported an increase in interleukin (IL)-1ß and IL-17 levels, and a continuous activation of caspase-1 in early rheumatoid arthritis (RA) patients. These results suggest that drugs targeting IL-1ß regulatory pathways, in addition to tumor necrosis factor (TNF), may constitute promising therapeutic agents in early RA. We have recently used a THP-1 macrophage-like cell line to screen 2320 compounds for those that down-regulate both IL-1ß and TNF secretion. Celastrol was one of the most promising therapeutic candidates identified in that study. Our main goal in the present work was to investigate whether administration of celastrol is able to attenuate inflammation in a rat model of adjuvant-induced arthritis (AIA). Moreover, since IL-1ß is known to play a role in the polarization of Th17 cells, we also investigate whether administration of digoxin, a specific inhibitor of Th17 cells polarization, is able to attenuate inflammation in the same rat model. We found that celastrol administration significantly suppressed joint inflammation. The histological and immunohistochemical evaluation revealed that celastrol-treated rats had a normal joint structure with complete abrogation of the inflammatory infiltrate and cellular proliferation. In contrast, we observed that digoxin administration significantly ameliorated inflammation but only if administrated in the early phase of disease course (after 4days of disease induction), and it was not efficient at inhibiting the infiltration of immune cells within the joint and in preventing damage. Thus, our results suggest that celastrol has significant anti-inflammatory and anti-proliferative properties and can constitute a potential anti-inflammatory drug with therapeutic efficacy in the treatment of immune-mediated inflammatory diseases such as RA. Furthermore, we find that early inhibition of Th17 cells polarization ameliorates arthritis but it is not as effective as celastrol.

Position paper on tuberculosis screening in patients with immune mediated inflammatory diseases candidates for biological therapy.

UNLABELLED: Chronic immunosuppression is a known risk factor for tuberculosis. Our aim was to reach a consensus on screening and prevention of tuberculosis in patients with immune mediated inflammatory diseases candidates to biologic therapy. METHODS: Critical appraisal of the literature and expert opinion on immunosuppressive therapies and risk of tuberculosis. RESULTS AND CONCLUSION: The currently recommended method for screening is the tuberculin skin test and the interferon gamma assay, after exclusion of active tuberculosis. Positively screened patients should be treated for latent tuberculosis infection. Patients may start biological therapy after 1 to 2 months, as long as they are strictly adhering to and tolerating their preventive regimen.

Bone histomorphometry revisited.

Bone histomorphometry is defined as a quantitative evaluation of bone micro architecture, remodelling and metabolism. Bone metabolic assessment is based on a dynamic process, which provides data on bone matrix formation rate by incorporating a tetracycline compound. In the static evaluation, samples are stained and a semi-automatic technique is applied in order to obtain bone microarchitectural parameters such as trabecular area, perimeter and width. These parameters are in 2D, but they can be extrapolated into 3D, applying a stereological formula. Histomorphometry can be applied to different areas; however, in recent decades it has been a relevant tool in monitoring the effect of drug administration in bone. The main challenge for the future will be the development of noninvasive methods that can give similar information. In the herein review paper we will discuss the general principles and main applications of bone histomorphometry.

Body composition phenotypes in systemic lupus erythematosus and rheumatoid arthritis: a comparative study of Caucasian female patients.

OBJECTIVES: The amount and distribution of fat and lean mass have important implications for health and systemic inflammation may represent a risk for altered body composition. The aim of this study was to analyse whether changes in body composition are similarly associated with systemic lupus erythematosus (SLE) and rheumatoid arthritis (RA), two inflammatory conditions of different pathogenesis. METHODS: Body mass index (BMI), waist circumference, fat mass (FM) and fat-free mass (FFM) were measured in 92 women with SLE, 89 with RA and 107 controls. Results were compared among the 3 groups and correlations of FM percentage were explored within SLE and RA. RESULTS: Abnormal body composition was more frequent in women with SLE and RA than in non-inflammatory controls, despite having a similar BMI. RA diagnosis was significantly associated with overfat (OR=2.782, 95%CI 1.470-5.264; p=0.002) and central obesity (OR=2.998, 95%CI 1.016-8.841; p=0.04), while sarcopenia was more common among SLE (OR=3.003; 95%CI 1.178-7.676; p=0.01). Sarcopenic obesity, i.e. the coexistence of overfat with sarcopenia, was present in 6.5% of SLE and 5.6% of RA women, but no controls. Independent correlations of FM percentage in women with SLE included smoking, disease activity and CRP. In RA, education, disease activity and cumulative corticosteroid dose were identified as independent predictors of FM percentage. CONCLUSIONS: Women with SLE or RA diagnosis are more likely to have abnormal body composition phenotype, with some differences existing between these two conditions. Changes in body composition are partly explained by the inflammatory burden of disease and its treatment.

Reuma.pt - the rheumatic diseases portuguese register.

INTRODUCTION: Since June 2008, Portuguese rheumatologists have been collecting on a routine basis, data into the nationwide Reuma.pt, the Rheumatic Diseases Portuguese Register from the Portuguese Society of Rheumatology (SPR), which includes rheumatic patients (rheumatoid arthritis - RA, ankylosing spondylitis - AS, psoriatic arthritis - PsA and juvenile idiopathic arthritis - JIA) receiving biological therapies or patients receiving synthetic disease modifying anti-rheumatic drugs (DMARDs). The aim of this publication is to describe the structure of Reuma.pt and the population registered since June 2008. METHODS: Demographic and anthropometric data, life style habits, work status, co-morbidities, disease activity and functional assessment scores, previous and current therapies, adverse events codified by the Medical Dictionary for Regulatory Activities (MedDRA), reasons for discontinuation and laboratory measurements are registered at each visit. The platform is based on a structured electronic medical record linked to a SQL Server database. All Rheumatology Departments assigned to the Portuguese National Health Service (n=21), 2 Military Hospitals (Lisboa and Porto), 1 public-private Institution and 6 private centers adhered to the Register. Until now, 18 centers have entered data into Reuma.pt. RESULTS: By January 2011, 3438 patients and 16130 visits had been registered. 2162 (63%) were RA patients, 700 of them treated with biological agents and 1462 with synthetic DMARDs. From the 515 (15%) AS patients, 297 were medicated with biological and 218 with non-biological therapies. 293 (8%) were PsA patients, 151 treated with biological drugs and 142 with other treatment strategies. 368 (11%) had the diagnosis of JIA, 68 were under biological treatment and 300 were managed with other treatment options. The register also includes 100 (3%) patients with other rheumatic diseases, submitted to treatments that required hospital day care infusions including 18 exposed to biological therapies. CONCLUSIONS: Registers are crucial to ensure correct clinical use, adequate assessment of post-marketing biological therapies' efficacy and safety, thus contributing for a better cost-benefit ratio. Reuma.pt, is a powerful and accurate tool to answer to these unmet needs. It presents a national coverage of the rheumatology centers and constitutes an invaluable resource for scientific research and to improve rheumatic patients care.

BioRePortAP, an electronic clinical record coupled with a database: an example of its use in a single centre.

AIMS: To evaluate the efficacy and safety of the treatment of psoriatic arthritis (PsA) patients with tumor necrosis factor (TNF) antagonists in the Rheumatology Department of Hospital de Santa Maria using the BioRePortAP. METHODS: The Portuguese Society of Rheumatology (SPR) developed an electronic medical chart coupled with a database for the follow up of PsA patients, the BioRePortAP, which was launched in May 2009. This evaluation was based on all the PsA patients that were on active treatment with TNF antagonists in September 2009 and were registered in the BioRePortAP. All the previous data on these patients were introduced in BioRePortAP using the prospective paper based follow up protocol that this Department was using since 1999. Only patients with more than 9 months of treatment were analyzed. RESULTS: Forty-two patients with PsA, actively treated with anti-TNF agents in September 2009, for at least 9 months, were analyzed in BioRePortAP. Twenty-three patients were male (55%) and nineteen were female (45%). The average age of these patients was 49.8+/-10.9 years old, the average disease duration was of 10.7+/-5.6 years and the mean duration of biological therapy was of 37.8+/-27.8 months. For the 81% of patients with peripheral joint disease there was a mean reduction of more than 80% in the swollen and tender joint counts, and almost 50% in the health assessment questionnaire (HAQ) value. In the 19% of the patients with axial involvement the reduction of BASDAI and BASFI was not statistically significative. On top of that, PASI score suffered a reduction of 64%. Fourteen patients (33.3%) had to switch their TNF antagonist treatment. 58.8% of the switches were due to adverse effects and 41.2% due to therapy failure. Regarding the 56 adverse reactions registered, only one was a severe reaction. The remaining adverse reactions were not severe and 67% of them were due to infections. DISCUSSION: The results of this first report of the use of the BioRePortAP in clinical practice confirm the efficacy and safety of TNF antagonist treatment in PsA. The results shown here elucidate the potential applications of BioRePortAP as a tool for efficacy and safety assessment of PsA patients treated with biotechnological drugs.

Evaluation of bone mechanical strenght and fracture risk assessment (Frax) in patients with hip joint replacement surgery.

BACKGROUND: Fracture risk assessment tools are useful to calculate the long term probability of osteoporotic fracture. However, how it reflects bone quality is unknown. The aim of this study was to correlate the WHO clinical fracture risk assessment tool, FRAX, with bone mechanical properties. METHODS: Six patients submitted to hip replacement surgery, either due to osteoporotic fractures or to osteoarthritis, were evaluated. Bone samples were collected and the mechanical properties assessed by compression tests. Patients' data regarding the presence of clinical risk factors for fracture were registered. Laboratorial assessment of bone metabolic parameters and a dual X-ray absorptiometry(DXA) were done. RESULTS: Analysis of the load-displacement curves showed that patients with fragility fractures (n=4) had low values of elastic modulus, yield load and energy absorbed until yield point. Osteoarthritis patients tend to have a better biomechanical performance.Femoral neck DXA scan was also performed in 3 patients. Fragility fracture patients had a lower bone mineral density than the patients with osteoarthritis. FRAX algorithm was applied and a positive relation was found between FRAX results and biomechanical parameters. Blood bone metabolic markers were within the normal range for all the subjects. CONCLUSIONS: The worse mechanical properties observed in the fragility fracture patients were related to high probability of fracture given by FRAX. These observations, in a very small sample, need further confirmation. However, they suggest that the fracture risk assessment tool, FRAX, may reflect the current mechanical bone behavior of the patient.

Interleukin-6 as a key player in systemic inflammation and joint destruction.

Interleukin-6 (IL-6) is a cytokine that can facilitate autoimmune phenomena, amplify acute inflammation and promote the evolution into a chronic inflammatory state. In addition, it is a major promoter of bone resorption in pathological conditions. In particular, IL-6 has a pivotal role in synovitis, bone erosions and in the systemic features of inflammation. This cytokine specifically binds to IL-6 receptor (IL-6R), forming the IL-6/IL-6R complex that binds to gp130, a membrane-bound protein, which is involved in non-ligand-binding signal transduction. Targeting IL-6R in both animal models of arthritis and in rheumatoid arthritis patients with a humanized anti IL-6R monoclonal antibody (tocilizumab) effectively controls local and systemic inflammatory manifestations and blocks cartilage and bone destruction. Given the pleiotropic function of IL-6 it can be anticipated that other inflammatory diseases and bone metabolic conditions might benefit from selective IL-6 signaling inhibition.

Osteoimmunology--the hidden immune regulation of bone.

Osteoimmunology is an emerging field of research dedicated to the investigation of the interactions between the immune and skeletal systems. These interactions are not only mediated by the release of cytokines and chemokines but also by direct cell-cell contact. Recently, it was proposed that immunoreceptors found in the immune cells are also an essential signal for osteoclasts activation, along with receptor activator NF-kappaB (RANK) ligand (RANKL) and macrophage-colony stimulating factor (M-CSF). In addition, adipose tissue also produces several factors (adipokines) that are known to interfere with the immune system and bone homeostasis. Chronic inflammation strongly influences osteoimmunology determining profound metabolic, structural and functional changes in bone.

Factors influencing calcaneus quantitative ultrasound measurements in an urban population.

OBJECTIVE: To estimate the effect of demographic, social, behavioural and anthropometric factors on quantitative ultrasound (QUS) parameters in an urban population. METHODS: Cross-sectional evaluation of consecutive subjects selected as part of the EPIPorto study, Portugal. Information was obtained on demographic, social, clinical and behavioural characteristics using a standard protocol. Calcaneus QUS parameters (Broadband Ultrasound Attenuation-BUA, and Speed of Sound-SOS) were obtained for men and women, stratified by age group. Comparisons according to exposure levels were made using the Kruskal-Wallis test and the multivariate effect on QUS parameters was estimated by linear regression. RESULTS: 1482 consecutive subjects (1010 females and 472 males), aged from 18 to 92 years. Higher levels of QUS parameters were found in the younger groups and progressive decrease with age were reported. Men showed higher values as compared to women in all parameters and differences between them increased with age. Differences were significant for BUA after the age of 39 and for SOS after the age of 59. In women, the multivariate model showed that age, body mass index (BMI) and smoking status were independent predictors of BUA and SOS. In men, age, BMI and calcium intake were significantly associated with BUA and SOS. CONCLUSION: The reference values in our Portuguese population are similar to others obtained in Southern European countries. In the Portuguese population, QUS parameters have age, sex and BMI as its major determinants. In addition, BUA and SOS may reflect specific bone characteristics influenced by a different set of independent determinants.

Inflammatory cell infiltrate and RANKL/OPG expression in rheumatoid synovium: comparison with other inflammatory arthropathies and correlation with outcome.

OBJECTIVES: To evaluate if the immunofluorescence analysis of synovial tissue (ST) using antibodies against RANKL/OPG, conjugated with the immunophenotyping of lymphocytes and macrophages, could be of diagnostic and prognostic value in rheumatoid arthritis (RA) patients. METHODS: 3-year prospective study of 103 consecutive patients submitted to closed needle biopsy for diagnostic purposes. ST was analyzed with routine histologic techniques and immunofluorescence, using monoclonal antibodies against RANKL, OPG, CD163, CD68, CD4, CD8, interferon-gamma and CD19. Patients were prospectively evaluated with a clinical, laboratorial and radiological protocol. At the end of the follow-up patients were divided according to the final diagnosis. Results of the initial histologic evaluation were compared between the main diagnostic groups and in RA patients histologic data was correlated with clinical and radiologic outcome measures. RESULTS: The RANKL/OPG ratio and the inflammatory infiltrate were significatively higher in RA (n = 25) as compared to the same ratio observed in other inflammatory joint diseases (OIJD, n = 48) and in osteoarthritis (n = 17). The difference between RA and OIJD was specifically confirmed when the comparison involved spondyloarthropathy (n = 26). Final HAQ score and radiologic outcome were correlated with the density of intimal CD68+ macrophages. Radiologic progression was correlated with subintimal CD4+ lymphocytes and CD68+ macrophages and intimal CD68 and CD163+ macrophages. CONCLUSION: The quantification of the RANKL/OPG ratio and of the number of lymphocytes in the ST might be useful to differentiate RA from other inflammatory joint diseases. The ST number of CD4+ lymphocytes and macrophages are probable predictors of radiologic progression in RA patients.

Dual effects of caspase-1, interleukin-1 beta, tumour necrosis factor-alpha and nerve growth factor receptor in inflammatory myopathies.

OBJECTIVE: To analyse the expression of factors potentially involved in skeletal muscle degeneration and regeneration in dermatomyositis (DM), systemic sclerosis (SSc), polymyositis (PM), systemic lupus erythematosus (SLE) and non-inflammatory myopathies. METHODS: Immunohistochemical staining of skeletal muscle biopsies (10 DM, 10 SSc, 10 PM, 10 SLE, 10 non-inflammatory myopathies) for tumour necrosis factor-alpha (TNF-alpha), interleukin-1 beta (IL-1 beta), activated caspase-1, pan-macrophage marker CD68, inducible nitric oxide synthase (NOS2) and nerve growth factor receptor (NGFR). TechMate staining robot and biotin-streptavidin protocol were used. RESULTS: Expression of TNF-alpha, IL-1 beta, caspase-1 and NOS2 was found in the cytoplasm and sarcolemma of dystrophic skeletal muscle fibres. TNF-alpha and IL-1 beta immunoreactive profiles were faint and few and close to satellite nuclei-containing regenerating muscle fibres both in inflammatory and non-inflammatory myopathies. NGFR expression was found in comparable areas. In non-inflammatory inherited myopathies more nuclei were caspase-1 immunoreactive whereas caspase-1 expression was rarely seen in inflammatory myopathies, implying regeneration of the affected muscle fibres. CONCLUSION: Prominent expression of the proinflammatory factors TNF-alpha, IL-1 beta and NOS2 and caspase-1 is associated with muscle fibre damage, albeit when expressed to a low degree these factors may, like NGFR, contribute to muscle regeneration and healing.

Macrophage subpopulations in rheumatoid synovium: reduced CD163 expression in CD4+ T lymphocyte-rich microenvironments.

OBJECTIVE: The cell surface glycoprotein CD163 is a member of the cysteine-rich scavenger receptor family, highly specific for leukocytes of the mononuclear phagocyte lineage. In vitro, it is induced by glucocorticoids, interleukin-6 (IL-6), and IL-10 and down-regulated by interferon-gamma (IFNgamma), indicating that it has a role in antiinflammatory or other immunomodulatory pathways. We assessed CD163 expression in microenvironments within rheumatoid arthritis (RA) synovium to clarify the relationships among CD4+ T lymphocytes, IFNgamma, and macrophage function in RA. METHODS: Double immunofluorescence and serial immunoenzymatic studies were performed on normal, osteoarthritic, and RA synovium and tonsil with antibodies to CD163, CD45, CD68, CD14, CD3, CD4, CD8, CD19, and IFNgamma. RESULTS: CD163 was observed on all CD14+ cells in synovium and tonsil with the exception of cells within larger T lymphocyte clusters in synovium and within tonsillar follicles. All brightly CD14+ cells in or around vessel walls (interpreted as immigrant monocytes) were CD163+. CD163 labeled fewer cells than did CD68 in synovial intima, but all CD45+ intimal cells were CD163+. CD4+,IFNgamma+ T lymphocytes in RA synovium were chiefly localized within clusters containing CD68+, CD163- cells. CONCLUSION: Within RA synovium, CD163 has major advantages as a macrophage marker and does not appear to be restricted to "mature" macrophages. CD163 discriminates between synovial macrophages and synovial intimal fibroblasts, which also stain positively for CD68 in diseased tissue.

Histology of the synovial tissue: value of semiquantitative analysis for the prediction of joint erosions in rheumatoid arthritis.

OBJECTIVE: Routine histologic techniques are still the main procedure in the study of the synovial biopsy. The relationship between the typical histological changes of rheumatoid synovium and clinical manifestations has not been studied in detail. METHODS: With the aim of determining whether a simple semiquantitative method of evaluating the changes in closed synovial biopsies was of clinical value in assessing both the diagnosis and prognosis of rheumatoid arthritis (RA) patients, we evaluated retrospectively 72 synovial biopsy specimens (26 RA patients, 30 patients with other inflammatory diseases and 16 osteoarthritis patients). Scores (0-10) were assigned to each biopsy specimen for each of 6 histologic features: synoviocyte hyperplasia; fibrosis in the subsynovial layer; proliferating blood vessels; perivascular infiltrates of lymphocytes; focal aggregates of lymphocytes; and diffuse infiltrates of lymphocytes. Scores were compared between the 3 groups and also between the RA subgroups with early and late disease; positive and negative rheumatoid factor; with and without joint erosions; and with and without systemic disease. RESULTS: Significant differences in the mean global score (mean of the 6 scores) were found both between RA and osteoarthritis and between other inflammatory diseases and osteoarthritis (p < 0.01). The mean global score for RA was higher than the mean global score obtained for the other inflammatory diseases, but the difference was not significant. We found a significantly higher mean global score in the RA patients with erosions in comparison to the RA patients without erosions, this difference being particularly evident for the lymphocyte perivascular infiltrate (p < 0.05). There were no significant differences between the other RA subgroups. CONCLUSION: In this study we have identified differences, using routine histologic techniques, between the rheumatoid synovial membrane of patients with and without erosions. Based on our present observations we suggest that the intensity of inflammatory histological features and, in particular, a high percentage of vessels with perivascular lymphocyte infiltrate might be of prognostic value in RA.