New developments in magnetic resonance imaging of the nail unit

The evolution of dedicated magnetic resonance imaging (MRI) musculoskeletal equipment allows new sequences and better images of the nail unit. The use of MRI has modified the imaging strategies used in treating inflammatory arthritis. In the case of psoriatic arthritis (PsA), the MRI study of the nail unit identifies nail involvement, which appears as an initial lesion for the induction of distal phalanx damage and consequently of distal interphalangeal joint arthritis. All patients with psoriasis, even in the absence of a clinically evident onychopathy, show characteristic MRI changes in the nail. This evidence could have a practical diagnostic value, because MRI study of the nail could document diagnosis in patients with undifferentiated spondyloarthropathies who have a barely evident psoriasis. We discuss the advantages and problems related to the use of low-field and high-field MRI in the study of the nail unit of patients with PsA.

Swollen joint count in psoriatic arthritis is associated with progressive radiological damage in hands and feet

OBJECTIVES

Psoriatic arthritis (PsA) may progress to joint damage. Determining clinical predictors of joint damage assessed by radiography is important. The aim of this study was to determine clinical factors as possible predictors for radiological damage in hands and feet of PsA patients with a 12-month follow-up.

METHODS

We conducted a retrospective study on 53 PsA patients who were taking disease-modifying anti-rheumatic drugs (DMARDs) and/or tumour necrosis factor (TNF)-alpha-blockers at a fixed dosage. The patients were observed in 118 follow-up visits (intervals of 12 months ± 3 months), according to a clinical and radiological protocol which included the documentation of the number of swollen and tender joints in hands and feet, the applied therapy, psoriasis, erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), and global health assessment. Outcome was defined as radiographic damage of hands and feet (Ratingen score). For the statistical analysis the Chi-Square test for 2x2 crosstables (with Fisher's correction, as required) was used.

RESULTS

Progressive radiological damage was more frequent among patients with an increasing swollen joint count (8 of 26 visits; 30.8%) than among those with a stable or decreased number of swollen joints (5 of 89 visits; 5.6%; p=0.001). The analysis of the patients stratified into the different treatment modalities resulted in a significant higher rate of radiological progress (20.8%) in patients on DMARD therapy compared with TNF-alpha blocking agents (0%) (p=0.009).

CONCLUSIONS

During a 12-month follow-up of PsA patients, an increasing number of swollen joints heralds progression of radiological damage. TNF-alpha-blocker therapy appears to be superior to DMARDs in the protection from radiological progress.

Analysis of granulysin-mediated cytotoxicity in peripheral blood of patients with psoriatic arthritis

The objective of the present study was to investigate possible changes in granulysin (GNLY)-mediated cytotoxicity of peripheral blood lymphocytes in psoriatic arthritis (PsA) patients with respect to different phases of the disease. We prospectively enrolled 25 PsA patients in the active phase, 26 PsA patients in remission and 24 healthy controls. The simultaneous detection of intracellular GNLY and cell surface antigens (CD3 and CD56) was performed with flow cytometry. GNLY apoptotic protein was visualised by immunocytochemistry. Natural killer (NK) cell cytotoxicity was analysed with a cytotoxicity assay against human erythroleukaemia K-562 cells. The percentage of GNLY(+) cells did not differ significantly between PsA patients in the acute phase and those in remission; however, it was always higher than in healthy examinees due to the increased percentage of GNLY(+) cells within T cells, NKT cells, and both, and in the CD56(+dim) and CD56(+bright) NK subsets. The mean fluorescence intensity for GNLY was higher in all lymphocyte subpopulations in the acute phase than in remission and in healthy controls. Accordingly, GNLY-mediated NK cell cytotoxicity against K-562 cells of active phase PsA patients was significantly higher than that in patients in remission or in healthy controls. These findings demonstrated the involvement of GNLY in the worsening of PsA and suggested that GNLY mediated the development of joint lesions.

Clinical presentation of psoriatic arthritis

Psoriatic arthritis is a spondyloarthropathy which occurs in patients with skin and/or nail psoriasis. Basing its characterization on morphological purposes, several types of arthritis have been described. Alternatively, we propose a simplified classification into three subsets, focusing on the levels of expression of cutaneous and articular elements which devise this syndrome. The first is established psoriatic arthritis which occurs in patients with evident or remittent skin and/or nail psoriasis. Its clinical spectrum consists of the five subsets classically described by Moll and Wright in 1973. The second is psoriatic arthritis "sine psoriasis" which occurs in subjects without psoriasis but with a family history of the disease in first or second-degree relatives. The third is early psoriatic arthritis which consists of an articular involvement of recent onset, occurring in subjects belonging to established or sine psoriasis subsets.

Synovitis in psoriatic arthritis: immunohistochemistry, comparisons with rheumatoid arthritis, and effects of therapy

Psoriatic arthritis (PsA) is a chronic inflammatory arthropathy associated with psoriasis that affects the peripheral joints, spine, and entheses. Most patients with PsA present with peripheral synovitis of the oligoarticular or polyarticular subtype. As one of the targets of this disease, studies on the synovium may provide insight into the mechanisms involved in this condition. Key findings from the available studies comparing synovial tissue of PsA and rheumatoid arthritis patients are discussed in this review. Also, changes in the synovial infiltrate, expression of proinflammatory cytokines and adhesion molecules, and vascularity in synovial tissue after treatment with various medications are addressed. Finally, a model for proof-of-principle study design using serial synovial biopsies is described, which could be used to predict clinical (in)efficacy in early clinical trial design in PsA.

TSG-6 inhibits osteoclast activity via an autocrine mechanism and is functionally synergistic with osteoprotegerin

OBJECTIVE

TSG-6 (the product of tumor necrosis factor [TNF]-stimulated gene 6) has a potent inhibitory effect on RANKL-mediated bone erosion. The aim of this study was to compare the activity of TSG-6 with that of osteoprotegerin (OPG) and to investigate its role as an autocrine modulator of cytokine-mediated osteoclast formation/activation. We also determined TSG-6 expression in inflammatory joint disease.

METHODS

The effects of TSG-6, OPG, and the inflammation mediators TNFα, interleukin-1 (IL-1), and IL-6 on the formation of osteoclasts from peripheral blood mononuclear cells and synovial fluid (SF) macrophages were determined by tartrate-resistant acid phosphatase staining. Lacunar resorption and filamentous actin ring formation were measured as indicators of osteoclast activity. The amount of TSG-6 in culture media or SF was quantified by enzyme-linked immunosorbent assay, and expression of TSG-6 in synovial tissue was assessed by immunohistochemistry.

RESULTS

TSG-6 acted in synergy with OPG to inhibit RANKL-mediated bone resorption and was produced by osteoclast precursors and mature osteoclasts in response to TNFα, IL-1, and IL-6. Expression of TSG-6 correlated with inhibition of lacunar resorption; this effect was ameliorated by an anti-TSG-6 antibody. The level of TSG-6 protein was determined in SF from patients with various arthritides; it was highest in patients with inflammatory conditions such as rheumatoid arthritis, in which it correlated with the amount of TSG-6 immunostaining in the synovium. TSG-6 inhibited the activation but not the formation of osteoclasts from SF macrophages.

CONCLUSION

In the presence of inflammatory cytokines, osteoclasts produced TSG-6 at concentrations that are sufficient to inhibit lacunar resorption. This may represent an autocrine mechanism to limit the degree of bone erosion during joint inflammation.

Zoledronic acid does not reduce MRI erosive progression in PsA but may suppress bone oedema: the Zoledronic Acid in Psoriatic Arthritis (ZAPA) Study

BACKGROUND

The effect of zoledronic acid (ZA) on articular bone in patients with psoriatic arthritis (PsA) was investigated using MRI.

METHODS

Patients with erosive PsA were randomised to receive 3-monthly infusions of ZA or placebo for 1 year. An additional 'tests alone' group received no infusions. Clinical assessments and MRI scans were performed at baseline and 1 year.

RESULTS

Paired 1.5T MRI scans were available in 22 patients including 6 who received ZA and 16 who did not (non-ZA = 6 placebo + 10 'tests alone' patients). The Disease Activity Score (28 swollen and tender joints, C reactive protein fell over 12 months to a greater degree in patients on ZA than in non-ZA patients (-1.6 vs -0.3, p=0.023). The MRI bone oedema score decreased in the ZA group (15.5 to 8.5) but increased in the non-ZA group (14.0 to 18.0) (p= 0.0056) with regression of bone oedema at 13.5% of sites in ZA patients vs 1.3% in non-ZA patients (p = 0.0073) and progression in 1.3% of sites in ZA patients vs 6.9% in non-ZA patients (p = 0.072). There was no difference between groups in change in MRI erosion score.

CONCLUSIONS

In this pilot study ZA reduced the progression of MRI bone oedema, indicating probable suppression of osteitis concordant with reduction in clinical measures of disease activity.

Subtype specific genetic associations for juvenile idiopathic arthritis: ERAP1 with the enthesitis related arthritis subtype and IL23R with juvenile psoriatic arthritis

INTRODUCTION

Juvenile idiopathic arthritis (JIA) is an umbrella term for all chronic childhood arthropathies and can be divided into seven subtypes. It includes the enthesitis related arthritis (ERA) subtype which displays symptoms similar to ankylosing spondylitis (AS) and juvenile-onset psoriatic arthritis which has similarities to psoriatic arthritis (PsA) and psoriasis (Ps). We, therefore, hypothesized that two well-established susceptibility loci for AS and Ps, ERAP1 and IL23R, could also confer susceptibility to these JIA subtypes.

METHODS

Single nucleotide polymorphisms (SNPs) in ERAP1 (rs30187) and IL23R (rs11209026) were genotyped in JIA cases (n = 1,054) and healthy controls (n = 5,200). Genotype frequencies were compared between all JIA cases and controls using the Cochrane-Armitage trend test implemented in PLINK. Stratified analysis by ILAR subtype was performed.

RESULTS

The ERA subtype showed strong association with ERAP1 SNP (P trend = 0.005). The IL23R SNP showed significant association in the PsA subtype (P trend = 0.04). The SNPs were not associated with JIA overall or with any other subtype.

CONCLUSIONS

We present evidence for subtype specific association of the ERAP1 gene with ERA JIA and the IL23R gene with juvenile-onset PsA. The findings will require validation in independent JIA datasets. These results suggest distinct pathogenic pathways in these subtypes.

Utility-based outcomes made easy: the number needed per quality-adjusted life year gained. An observational cohort study of tumor necrosis factor blockade in inflammatory arthritis from Southern Sweden

OBJECTIVE

To introduce a novel, simple, utility-based outcome measure, the number needed per quality-adjusted life year (QALY) gained (NNQ), and to apply it in clinical practice in anti-tumor necrosis factor (anti-TNF)-treated patients with rheumatoid arthritis (RA), psoriatic arthritis (PsA), and spondylarthritis (SpA).

METHODS

The NNQ is the number of patients one has to treat in order to gain 1 QALY. It is calculated as the inverted value of the utility gain (area under the curve) over 1 year in a cohort subjected to an intervention. EuroQol Index utility data from the South Swedish Arthritis Treatment register were used.

RESULTS

Patients with RA (n = 1,001), PsA (n = 241), and SpA (n = 255) were eligible for the study. First, second, and third treatment courses were studied. For RA, NNQ was 4.5, 6.4, and 5.2 for first, second, and third courses, respectively. For PsA and SpA, NNQ was 4.2-4.5, irrespective of treatment order. Treatment groups with <50 patients were not analyzed. During the study period 2002-2007, there were no secular trends of utility gains.

CONCLUSION

The NNQ is an easily derived and understandable utility-based outcome measure that may be useful for stakeholders and decision makers as well as for clinicians. It was readily applied in this study of TNF blockade across 3 arthritis diagnoses. NNQ varied little over diagnoses and treatment course order, with a possible exception in second treatment course in RA.

Synovial effusion and synovial fluid biomarkers in psoriatic arthritis to assess intraarticular tumor necrosis factor-α blockade in the knee joint

INTRODUCTION

The purpose of this study was the evaluation of synovial effusion (SE), synovial fluid (SF) and synovial tissue (ST) biomarkers in relation to disease activity indexes to assess the response to intraarticular (IA) tumor necrosis factor (TNF)-α blockers in psoriatic arthritis (PsA).

METHODS

Systemic and local disease activity indexes (disease activity score (DAS); the Ritchie articular index (mRAI), erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP); Thompson articular (THOMP) and joint articular (KJAI)-Index ) and ST samples were assessed at baseline, throughout treatment, and during the follow-up in 14 patients affected with PsA who underwent IA injections (0.5 ml to 12.5 mg) in the knee joint of etanercept (E) or placebo (P) once every two weeks for a 10-week period. Total SF white blood cell (WBC) counts (WBC/μl) and SF cytokine/chemokine (CK/CCK) levels were measured before IA-E at baseline, after IA-E, and as long as there were adequate amounts of SF for knee aspiration (post). Characterization of synovial mononuclear cell infiltration and synovial vessels was carried out in 8 out of 14 knees by staining serial sections of synovial tissue biopsies for CD45, CD3, CD68, CD31 and CD105.

RESULTS

At baseline, CRP and/or ESR were significantly correlated with SF-CK (interleukin- (IL-)1β, IL-1Ra, IL-6, IL-8) and CCK (CCL3). Post-IA injections, there was a decrease in SE in the knees in which aspiration following IA-E injection was possible as well as a significant reduction in SF WBC/μl and in SF-CK (IL-1β, IL-1Ra, IL-6 and IL-22). Pre- and post-IA-E injections, there were significant correlations between ST markers and SF-CK (IL-1β with CD45; IL-1β and IL-6 with CD31) and between SF-CCK (CCL4 and CCL3 with CD3). At the end of the study, there was a significant reduction in disease activity indexes (CRP, DAS, RAI, THOMP, KJAI) as well as in the ST markers (CD45; CD3).

CONCLUSIONS

Synovial effusion regression is a reliable indicator of the response to IA TNF-α blockers in PsA patients as it is confirmed by the correlation between SF biomarkers to disease activity and synovial tissue inflammation.

Synovial tissue hypoxia and inflammation in vivo

INTRODUCTION

Hypoxia is a microenvironmental feature in the inflamed joint, which promotes survival advantage for cells. The aim of this study was to examine the relationship of partial oxygen pressure in the synovial tissue (tPO(2)) in patients with inflammatory arthritis with macroscopic/microscopic inflammation and local levels of proinflammatory mediators.

METHODS

Patients with inflammatory arthritis underwent full clinical assessment and video arthroscopy to quantify macroscopic synovitis and measure synovial tPO(2) under direct visualisation. Cell specific markers (CD3 (T cells), CD68 (macrophages), Ki67 (cell proliferation) and terminal deoxynucleotidyl transferase dUTP nick end labelling (cell apoptosis)) were quantified by immunohistology. In vitro migration was assessed in primary and normal synoviocytes (synovial fibroblast cells (SFCs)) using a wound repair scratch assay. Levels of tumour necrosis factor alpha (TNFalpha), interleukin 1beta (IL1beta), interferon gamma (IFNgamma), IL6, macrophage inflammatory protein 3alpha (MIP3alpha) and IL8 were quantified, in matched serum and synovial fluid, by multiplex cytokine assay and ELISA.

RESULTS

The tPO(2) was 22.5 (range 3.2-54.1) mm Hg and correlated inversely with macroscopic synovitis (r=-0.421, p=0.02), sublining CD3 cells (-0.611, p<0.01) and sublining CD68 cells (r=-0.615, p<0.001). No relationship with cell proliferation or apoptosis was found. Primary and normal SFCs exposed to 1% and 3% oxygen (reflecting the median tPO(2) in vivo) induced cell migration. This was coupled with significantly higher levels of synovial fluid tumour necrosis factor alpha (TNFalpha), IL1beta, IFNgamma and MIP3alpha in patients with tPO(2) <20 mm Hg (all p values <0.05).

CONCLUSIONS

This is the first study to show a direct in vivo correlation between synovial tPO(2), inflammation and cell migration, thus it is proposed that hypoxia is a possible primary driver of inflammatory processes in the arthritic joint.

Ultrasound imaging for the rheumatologist XXVI. Sonographic assessment of the knee in patients with psoriatic arthritis

Psoriatic arthritis (PsA) is an arthropathy associated to psoriasis, which is part of the spondyloarthropathy family, and which may present with various forms, from mono-oligoarthritis to symmetric polyarthritis mimicking rheumatoid arthritis. In longstanding disease, the symmetric polyarthritis is the most common pattern of PsA, involving small joint of hands, feet, wrists, ankles and, very frequently, knees. Other common features are represented by the inflammation of enthesis and tendons. Ultrasound (US) examinations were performed using a Logiq 9 (General Electric Medical Systems, Milwaukee, WI) equipped with a multifrequency linear probe, working at 10-14 MHz. One-hundred and sixty-six knee joints were investigated in a total of 83 patients. Prior to US assessment, all patients underwent a clinical examination by an expert rheumatologist who recorded the presence/absence of pain, tenderness (detected by palpation and/or active or passive mobilisation of the knee), and knee swelling. Sixty-two (74.7%) knee joints were found clinically involved, while at least one US finding indicative of joint inflammation was obtained in 70 (84.3%) knee joints. In the 59% of the patients we noticed synovial hypertrophy. Enthesitis was present in 39.7% of the subjects studied. This study demonstrated that US detected a higher number of inflamed knee joints and enthesis with respect to clinical assessment in PsA patients.

Longitudinal perspectives on event history analysis

We discuss event histories from the point of view of longitudinal data analysis, comparing several possible inferential objectives. We show that the Nelson-Aalen estimate of a cumulative intensity may be derived as a limiting solution to a sequence of generalized estimating equations for intermittently observed longitudinal count data. We outline a potential use for the theory in interval-censored recurrent-event models, and demonstrate its applicability using data from a Toronto arthritis clinic. We also discuss connections with rate models, along with some implications for the longitudinal analyst.

Atypical presentation of histoplasmosis in a patient with psoriasis and psoriatic arthritis on infliximab therapy

Infliximab is a chimeric monoclonal antibody to TNF-alpha which acts on both the soluble and transmembrane forms of TNF-alpha. It has been used successfully for the treatment of psoriasis and psoriatic arthritis, rheumatoid arthritis, Crohn's disease and ankylosing spondylitis either as monotherapy or in combination with drugs such as methotrexate. To date, over 20,440 patients with moderate-to-severe psoriasis have been treated with infliximab worldwide. Opportunistic infections and reactivation of underlying latent infections are an area of concern with the use of infliximab particularly when used in conjunction with other immunosuppresants. The authors report a case of histoplasmosis presenting with signs of severe hypercalcemia and renal failure in a patient on infliximab for approximately three years in combination with low dosages of methotrexate and prednisone. This report stresses the importance of maintaining a high index of suspicion for unusual pathogens while managing patients receiving TNF-alpha inhibitors, particularly when used in combination with other immunosuppressants. In addition, the authors emphasize the role of a multi-disciplinary approach and appropriate coordination among caregivers.

Dermatoglyphics in psoriatic symmetrical polyarthritis in fifty women--quantitative analysis

Quantitative dermatoglyphic analysis ofdigitopalmar ridge count was used to research psoriatic symmetrical polyarthritis in fifty women. Analyzed were 25 dermatoglyphics traits: number of epidermal ridges on all ten fingers, their sum for five and ten fingers, four traits on both palms, i.e., between a-b, b-c, c-d and a-d triradii, and atd angles and their bilateral sum. The data obtained were compared with those recorded in a control group of 200 pairs of imprints of phenotypically healthy females from Zagreb area. Statistically significant differences were found in 13 variables in decreased ridge count in all ten fingers, their sum in five and ten fingers separately. Accordingly, a polygenetic system identical in some loci to polygenic system predisposing to women psoriatic symmetrical polyarthritis susceptibility might be found responsible for the dermatoglyphic pattern development.

Psoriatic arthritis and chronic lymphoedema: treatment efficacy by adalimumab

Lymphoedema is a rare complication of psoriatic arthritis (PsA) and inflammatory joint disease, with no response noted to disease-modifying drugs. However, reports are emerging of a beneficial effect on lymphoedema in patients treated with tumor necrosis factor-alpha antagonists for PsA (Etanercept), rheumatoid arthritis (Etanercept) and ankylosing spondylitis (Infliximab). We describe a psoriatic arthritis patient whose lymphoedema greatly improved following commencement of adalimumab.