The link between enthesitis and arthritis in psoriatic arthritis: a switch to a vascular phenotype at insertions may play a role in arthritis development.

OBJECTIVE: Subclinical enthesopathy is recognised in both psoriasis and psoriatic arthritis (PsA). This study used ultrasonography with power Doppler (PD) to test the hypothesis that subclinical enthesopathy in PsA was associated with an 'inflammatory' or vascular phenotype compared to that seen in psoriasis. METHODS: 100 patients with a mean age of 46.3 years (SD 15) (42 with psoriasis and 58 with PsA) and 23 matched healthy controls (HC) from two centres were included. 1230 lower limb entheses were scanned by ultrasonographers blinded to clinical details. Both inflammatory and chronic features of enthesopathy were scored. RESULTS: Psoriasis patients (with or without arthritis) were more likely to express a vascular phenotype, with higher inflammation-related enthesopathy scores than HC (for inflammation p<0.0001, for chronicity p=0.02, for total ultrasound scores p<0.0001). The PsA patients had higher ultrasound enthesopathy scores than psoriasis patients (inflammation p=0.04, chronicity p=0.02) and HC (inflammation p<0.0001, chronicity p=0.003). When symptomatic entheses were excluded, PsA patients still had higher PD scores than psoriasis patients (p=0.003). Doppler positivity in at least one entheseal site was observed more frequently in PsA (21/58, 36.2%) versus psoriasis (4/42, 9.5%; p=0.002). CONCLUSIONS: This study shows that the ultrasound appearances of subclinical enthesitis in psoriasis differ from the subclinical enthesitis in PsA, with PsA patients having more PD. This is suggestive of a more inflammatory or vascular process in PsA, and offers potentially novel insights into the progression from skin to joint disease in psoriasis.

Methotrexate for pain relief in knee osteoarthritis: an open-label study.

OBJECTIVE: Synovitis is very common in knee OA and associated with pain. This open-label study evaluated an anti-synovitis therapy, MTX, for pain relief in knee OA. METHODS: Inclusion criteria included pain visual analogue scale (VAS) >40/100 mm, ACR clinical criteria for knee OA and intolerance/inefficacy of NSAID and opioids. US at baseline and 24 weeks assessed effusion and synovial thickness. Patients received MTX up to 20 mg/week for 24 weeks. RESULTS: Thirty participants were recruited; mean age 64.5 years, median pain VAS 68 mm. At 24 weeks, 13/30 (43%) achieved ≥30% reduction in pain VAS, 7 (23%) achieved ≥50% reduction and 4 (13%) had worsened. Thirteen achieved Osteoarthritis Research Society International (OARSI) responder criteria. All had effusion/synovitis at baseline. There was no correlation between change in imaging and change in pain scores at 24 weeks. CONCLUSION: This open-label trial suggests analgesic efficacy for MTX in OA knee and suggests that a randomized controlled trial is warranted. Trial Registration. Current controlled trials, http://www.controlled-trials.com/, ISRCTN66676866.

Potential use of optical coherence tomography and high-frequency ultrasound for the assessment of nail disease in psoriasis and psoriatic arthritis.

BACKGROUND/OBJECTIVE: Psoriatic nail disease is increasingly recognised to be of major clinical and research relevance. Clinical assessment remains the current gold standard for its evaluation. OBJECTIVE: We compared optical coherence tomography (OCT) and ultrasound (US) for nail disease assessment in psoriatic disease. METHODS: 18 patients with at least one involved nail and 12 healthy controls were scanned using OCT; psoriatic patients also had an US scan (using a linear probe at 9-14 MHz). Nail and contour abnormalities were documented. Clinical onychopathy was scored independently using the modified Nail Psoriasis Severity Index. RESULTS: Among 180 nails, 67.8% had clinical findings whereas 33.9% were abnormal by US and 44.4% had abnormalities on OCT. A positive OCT had a sensitivity and specificity of 44.4 and 95.8%, respectively, with a positive likelihood ratio of 10.7 for nail disease. OCT demonstrated 76.3% absolute agreement compared with clinical assessment and 65% with US. OCT detected subtle abnormalities in 12 clinically normal nails and in 41 nails with normal US findings. CONCLUSION: These findings show that OCT has a potential for the systematic characterisation of psoriatic nail changes and could be useful in diagnosis and more objective assessment of treatment response.

Psoriasis patients with nail disease have a greater magnitude of underlying systemic subclinical enthesopathy than those with normal nails.

OBJECTIVE: Enthesopathy is a major feature of psoriatic arthritis (PsA), which is supported by imaging studies. Given that nail disease often predates PsA and that the nail is directly anchored to entheses, the authors asked whether nail involvement in psoriasis equates with a systemic enthesopathy. METHODS: Forty-six patients with psoriasis (31 with nail disease) and 21 matched healthy controls (HC) were recruited. 804 entheses of upper and lower limbs were scanned by an ultrasonographer blinded to clinical details. RESULTS: Psoriasis patients had higher enthesitis scores than HC (median (range) 21 (0-65) vs 11 (3-39), p=0.005). Enthesopathy scores were higher in patients with nail disease (23 (0-65)) than in patients without nail disease (15 (5-26), p=0.02) and HC (11 (3-39), p=0.003). Inflammation scores of patients with nail disease (13 (0-34)) were higher than patients without nail disease (8 (2-15), p=0.02) and HC (5 (0-19), p<0.001). Modified nail psoriasis severity index scores were correlated to both inflammation (r(2)=0.45, p=0.005) and chronicity scores (r(2)=0.35, p=0.04). No link between the psoriasis area and severity index and enthesitis was evident. CONCLUSION: The link between nail disease and contemporaneous subclinical enthesopathy offers a novel anatomical basis for the predictive value of nail psoriasis for PsA evolution.

Ultrasonographic assessment of nail in psoriatic disease shows a link between onychopathy and distal interphalangeal joint extensor tendon enthesopathy.

OBJECTIVE: We compared ultrasonography (US) with the modified nail psoriasis severity index (mNAPSI) to investigate the nail plate, nail matrix and adjacent tendons in subjects with psoriatic nail disease and to test the hypothesis that nail involvement was specifically linked to extensor tendon enthesopathy. METHODS: 86 psoriatic patients (169 nails) and 20 healthy controls (HC) (40 nails) were assessed with both the mNAPSI and US. The thickness of the nail plate, nail matrix region and adjacent extensor tendon were assessed and compared with physical examination findings. RESULTS: A good agreement between clinical and sonographic nail findings was noted (kappa value = 0.52, p < 0.0001). Entheseal thickening of the extensor tendon on US was more frequent in patients with clinical nail disease compared to patients without clinical nail disease in both psoriasis and psoriatic arthritis (38 vs. 16%, p = 0.03, and 47 vs. 19%, p = 0.008, respectively). Nail thickness, nail matrix and adjacent skin thickness were higher in psoriatic patients compared to HC. CONCLUSION: US and clinical findings show good correlation for the assessment of the nail in psoriatic disease. The demonstration of extensor tendon enthesopathy in both psoriasis and psoriatic arthritis supports the importance of enthesopathy in nail disease pathogenesis whether or not clinical arthritis is present.

The Relationship Between Physical Examination and Ultrasonography of Large Entheses of the Achilles Tendon and Patellar Tendon Origin.

OBJECTIVE: To investigate the relationship between physical examination (PE) and sonographic features of enthesitis, based on anatomical sites. METHODS: The analysis was done using merged raw data of 3 studies on 2298 entheses. RESULTS: Patients with clinical Achilles enthesitis had more abnormalities on ultrasound (US): hypoechogenicity, p < 0.001; thickening, p = 0.001; Doppler signals, p = 0.002; and erosions, p = 0.02. The patellar tendon origin also correlated with PE but distal patellar tendon insertion and plantar aponeurosis were uncoupled from the US. CONCLUSION: The relationship between clinical and sonographic findings for large entheses is dependent on the anatomical site. For the patellar tendon origin and Achilles entheses, PE is significantly linked to US findings.

MRI for the assessment and monitoring of RA--what can it tell us?

The past 15 years has seen an exponential rise in the use of MRI for the assessment of rheumatoid arthritis (RA). In this Perspectives article, we review the current and potential future role of MRI in the diagnosis, prognosis and monitoring of RA. We also review the impact of MRI research on the understanding of disease mechanisms. In our view, the pivotal role of synovitis in RA and its predilection for sonographically accessible joints makes it likely that MRI will be used diagnostically in joints that are inaccessible to ultrasonography or where the differential diagnosis is unclear. Additionally, MRI will probably assume an even more prominent role in clinical trials where the aim of therapy is the complete ablation of synovitis. Given the ever-increasing sophistication of MRI, we anticipate that it will continue to be a key research tool in the coming years.

Structural damage in rheumatoid arthritis, psoriatic arthritis, and ankylosing spondylitis: traditional views, novel insights gained from TNF blockade, and concepts for the future.

Structural changes of bone and cartilage are a hallmark of inflammatory joint diseases such as rheumatoid arthritis (RA), psoriatic arthritis (PsA), and ankylosing spondylitis (AS). Despite certain similarities - in particular, inflammation as the driving force for structural changes - the three major inflammatory joint diseases show considerably different pathologies. Whereas RA primarily results in bone and cartilage resorption, PsA combines destructive elements with anabolic bone responses, and AS is the prototype of a hyper-responsive joint disease associated with substantial bone and cartilage apposition. In the present review we summarize the clinical picture and pathophysiologic processes of bone and cartilage damage in RA, PsA, and AS, we describe the key insights obtained from the introduction of TNF blockade, and we discuss the future challenges and frontiers of structural damage in arthritis.