Subclinical enthesitis in enthesitis-related arthritis and sacroiliitis associated with familial Mediterranean fever.

OBJECTIVES: In our study, we investigated the presence of subclinical enthesitis by ultrasonography (US) in asymptomatic patients with enthesitis-related arthritis (ERA) and sacroiliitis associated with familial Mediterranean fever (FMF). METHODS: A total of 50 patients, including 35 patients with ERA and 15 with sacroiliitis associated with FMF, were included in the study. All patients were evaluated with US by a paediatric radiologist. Enthesis of seven tendons (common extensor and flexor tendons, quadriceps tendon, proximal and distal patellar tendon, Achilles tendon, and plantar fascia) was examined on both sides. RESULTS: Subclinical enthesitis was detected in 10 ERA (28.5%) and three FMF (20%) patients. Enthesitis was radiologically diagnosed in 16 (2.3%) out of 700 evaluated entheseal sites. The most frequent sites of enthesitis were Achilles (37.5%) and quadriceps (31.3%) tendons. All patients were in clinical remission and had no active complaints, and acute phase reactants were within normal limits. Therefore, the patients were followed up without treatment change. However, disease flare-up was observed in three of these patients (23.1%) during the follow-up, and their treatments were intensified. CONCLUSIONS: Our results showed that the US can be particularly helpful in detecting subclinical enthesitis and predicting disease flare-ups.

Demonstrating the relationship of ultrasonographic parameters with disease activity and pain in lateral epicondylitis.

To evaluate the relationship of ultrasonographic evaluation parameters with pain, muscle strength and disease severity in lateral epicondylitis (LE). 64 people were included in present retrospective, cross-sectional study. Activity and rest pain was questioned with Visual Analog Scale (VAS). Also, Patient Rated Tennis Elbow Evaluation (PRTEE) and the maximum grip strength were evaluated. Hypoechoic region, neovascularity, cortical irregularity, enthesopathy and peritendinous fluid or bursitis were evaluated by ultrasonography. 48 of the patients were female and 16 were male. Mean age was 48.53 ±â€…6.12, body mass index was 27.70 ±â€…4.75. 55 (85.9%) hypoechoic region, 31 (48.4%) neovascularity, 21 (32.8%) cortical irregularity, 19 (29,7%) enthesopathy, and 18 (28.1%) peritendinous fluid or bursitis were detected by ultrasonography. When the ultrasonographic findings and clinical findings of the patients were compared, no significant difference was found between the hypoechoic region, cortical irregularity, enthesopathy and clinical findings (P > .05), while the extension grip strength was found to be significantly lower in patients with neovascularity (P = .045). In addition, patients with peritendinous fluid or bursitis, were found to be significantly lower in both flexion (P = .033) and extension (P = .023) grip strength, while PRTEE function (P = .021) subgroup and total (P = .038) scores were significantly higher. Hypoechoic region, cortical irregularities and enthesopathy were not evaluated to be associated with disease severity, pain and muscle strength. Neovascularity was found to be associated only with extension grip strength. Peritendinous fluid or bursitis was found to be associated with both flexion and extension grip strength and disease activity, but not associated with pain.

Utility of Musculoskeletal Ultrasound in Psoriatic Arthritis.

PURPOSE: Psoriatic arthritis (PsA) is a chronic autoimmune disease that causes a variety of musculoskeletal abnormalities. Musculoskeletal ultrasound in PsA is becoming increasingly popular, both in clinical practice and research. This narrative reviews recent literature on the utility of ultrasound in PsA. METHODS: A search of PubMed was used to identify publications written in English, with titles containing the term psoriatic arthritis and either ultrasound, ultrasonography, or sonographic. A total of 178 publications were identified; those that were not relevant (n = 59), were not original research (n = 45), or that had small (<30) sample sizes (n = 34) were excluded, leaving 40 studies for review of the use of ultrasound in various aspects of PsA. Publications with similar findings were grouped into seven domains: (1) the use of ultrasound findings compared to clinical assessment; (2) the use of ultrasound in the assessment of enthesitis; (3) the use of ultrasound in the assessment of nails; (4) the use of ultrasound as a screening tool in patients with psoriasis at risk for PsA; (5) the use of ultrasound in differentiating PsA from other similar conditions; (6) the use of ultrasound as a measure of disease activity; and (7) the use of ultrasound compared to MRI. FINDINGS: In recent studies, ultrasound measures of inflammation tended to agree with objective clinical findings of disease, such as swollen joint counts, while being less influenced by subjective measures, such as pain. Ultrasound has utility in the assessment of enthesitis and psoriatic nail disease in PsA, and as an overall measure of disease activity. Ultrasound-based outcomes measures have been used in observational studies and in clinical trials involving PsA, and may have utility as a measure of treatment response. The findings from recent studies suggest that ultrasound may have utility in improving the accuracy and precision of screening programs designed to identify subclinical PsA in cohorts of patients with psoriasis; however, cost-efficacy remains to be determined. Beyond screening, ultrasound may have utility in the diagnosis of PsA in patients with suspected inflammatory arthritis, and ultrasound measures of inflammation agree with MRI measures of inflammation, meaning that incorporating ultrasound into clinical practice might help to overcome the barriers associated with MRI. IMPLICATIONS: As ultrasound technology continues to advance, and associated costs decrease, it is likely that ultrasound will become more integrated into the clinical journeys of patients with PsA.

The use of ultrasound to detect enthesitis as a potential guide for intervention in patients with psoriasis at risk of psoriatic arthritis: a systematic review.

INTRODUCTION: Psoriatic arthritis is estimated to develop in 2% of patients with psoriasis per year and can result in significant morbidity. Early diagnosis and treatment of psoriatic arthritis are imperative to prevent irreversible arthritic joint damage. Dermatologists play a key role in identifying patients who are at risk for or with early signs of psoriatic arthritis. Subclinical enthesopathy may be a risk factor for psoriatic arthritis or an early sign of the disease and can be detected using ultrasound. METHODS: In this systematic review, we determined the prevalence of ultrasound-diagnosed enthesitis in psoriasis patients, as well as their risk of subsequent progression to psoriatic arthritis. RESULTS: We determined that the detection of enthesitis on ultrasound was associated with higher risk of future psoriatic arthritis. Systemic therapy was associated with improvement in enthesitis findings in patients with psoriasis but not in those with chronic structural damage or established psoriatic arthritis. Additionally, one study showed that ustekinumab treatment resulted in a significantly lower rate of psoriatic arthritis development. CONCLUSIONS: These studies support the value of early detection and treatment in the prevention of progression to psoriatic arthritis, as well as the use of ultrasound for screening for risk factors in psoriasis patients. Future studies are needed to further evaluate when preventative therapy can be useful among patients with psoriasis with risk factors for psoriatic arthritis.

Enthesitis in patients with psoriatic arthritis: A nationwide data from the Chinese Registry of Psoriatic Arthritis (CREPAR).

BACKGROUND: The clinical features of enthesitis in patients with psoriatic arthritis (PsA) have been reported in some Western countries, but data in China are very limited. This study aimed to describe the characteristics of enthesitis in Chinese patients with PsA and compared them with those in other cohorts. METHODS: Patients with PsA enrolled in the Chinese Registry of Psoriatic Arthritis (CREPAR) (December 2018 to June 2021) were included. Data including demographics, clinical characteristics, disease activity measures, and treatment were collected at enrollment. Enthesitis was assessed by the Spondyloarthritis Research Consortium of Canada (SPARCC), Maastricht ankylosing spondylitis enthesitis score (MASES), and Leeds enthesitis index (LEI) indices. A multivariable logistic model was used to identify factors related to enthesitis. We also compared our results with those of other cohorts. RESULTS: In total, 1074 PsA patients were included, 308 (28.7%) of whom had enthesitis. The average number of enthesitis was 3.3 ± 2.8 (range: 1.0-18.0). More than half of the patients (165, 53.6%) had one or two tender entheseal sites. Patients with enthesitis had an earlier age of onset for both psoriasis and arthritis, reported a higher proportion of PsA duration over 5 years, and had a higher percentage of axial involvement and greater disease activity. Multivariable logistic regression showed that axial involvement (odds ratio [OR] 2.21, 95% confidence interval [CI], 1.59-3.08; P <0.001), psoriasis area and severity index (PASI) (OR: 1.03, 95% CI: 1.01-1.04; P = 0.002), and disease activity score 28-C reactive protein (DAS28-CRP) (OR: 1.25, 95% CI: 1.01-1.55; P = 0.037) were associated with enthesitis. Compared with the results of other studies, Chinese patients with enthesitis had a younger age, lower body mass index (BMI), a higher rate of positive human leukocyte antigen (HLA)-B27, more frequent dactylitis, and a higher proportion of conventional synthetic disease-modifying antirheumatic drugs' (csDMARDs) use. CONCLUSIONS: Enthesitis is a common condition among Chinese patients with PsA. It is important to evaluate entheses in both peripheral and axial sites.

The role of ultrasound in screening subclinical psoriatic arthritis in patients with moderate to severe psoriasis.

OBJECTIVE: To identify patients in the subclinical psoriatic arthritis (Sub-PsA) phase by ultrasound (US) and provide a solution to screen them. METHODS: A total of 490 participants with moderate-to-severe psoriasis were evaluated. Among them, 384 participants without arthritis symptoms were enrolled into the silent psoriasis group and 106 participants with arthritis symptoms, called prodromal/active PsA phase, were enrolled into the clinical PsA group. Another 80 non-psoriasis participants were enrolled into the control group. Each participant received clinical assessments and US examinations of 60 joints, 38 tendons, and 40 entheses. We compared the incidences of synovio-enthesitis, synovitis, tenosynovitis, erosion, and dactylitis detected on US among the three groups. Subsequently, on the basis of significant US findings, we distinguished Sub-PsA from psoriasis alone (PsO) in the silent psoriasis group and analyzed the clinical characteristics, mainly including basic clinical characteristics, body surface area (BSA), and Psoriasis Area and Severity Index (PASI) score. RESULTS: Only synovio-enthesitis significantly differed between the control group and the silent psoriasis group (1.3% vs. 16.1%, p < 0.001). The knee was the most commonly involved site of synovio-enthesitis (79.0%). Taking synovio-enthesitis as the standard, 16.1% of silent psoriasis participants and 12.7% of all psoriasis participants were in the Sub-PsA phase. Furthermore, there were no differences in BSA and PASI among the three phases of PsO, Sub-PsA, and prodromal/active PsA. CONCLUSIONS: Since the psoriasis patients in Sub-PsA phase was as high as 12.7% in all patients with moderate-to-severe psoriasis, US-detected synovio-enthesitis was recommended routinely for screening them regardless of arthritis symptoms, especially in the lower limbs. KEY POINTS: • Synovio-enthesitis on ultrasound was significantly associated with subclinical psoriatic arthritis, especially in the lower limbs. • Routine ultrasound evaluation could help screen psoriasis patients in the subclinical psoriatic arthritis phase, which was as high as 12.7% in all psoriasis patients.

Evaluation of the agreement between the ACR 1990 fibromyalgia tender points and an enthesitis score in patients with axial spondyloarthritis.

OBJECTIVES: Coexistence of FM represents a challenge in the evaluation of enthesitis in patients with axial spondyloarthritis (axSpA) due to a possible overlap between the tender points (TP) due to enthesitis and those of FM. The objective was to assess the agreement between the MASES enthesitis score and the tender points of the ACR 1990 criteria in patients with axSpA. METHODS: This was a cross-sectional ancillary analysis of the Predict-SpA study (NCT03039088). Patients had a diagnosis of axSpA according to their rheumatologist and an indication to start a TNFα blocker. All patients were screened for FM according to the FiRST questionnaire. A physician was asked to assess 31 anatomically described sites in a random order without knowing to which instrument the site belonged (i.e. the 18 ACR 1990 TP and the 13 MASES sites). Agreement between the MASES and the ACR 1990 TPs by the intraclass correlation coefficient (ICC), also stratified by the presence/absence of concomitant FM according to the FiRST. RESULTS: Among the 526 patients, 53% were men and 202 (38%) had FM. Radiographic sacroiliitis and MRI sacroiliitis were present in 56% and 68% patients, respectively. Patients were mostly men (53.4%) with radiographic and MRI sacroiliitis in 56% and 68% patients, respectively. Mean number of ACR 1990 TP was 5.4 (s.d. 4.6) and mean MASES was 4.2 (s.d. 3.6). ICC between both scores was 0.7 [95% CI (0.6, 0.8)]. ICC between both scores was 0.6 [95% CI (0.3, 0.8)] and 0.7 [95% CI (0.6, 0.7)] for patients with and without FM, respectively. CONCLUSION: These results suggest a significant overlap between both scores in patients with axSpA, including in those without concomitant FM. TRIAL REGISTRATION: clinicaltrials.gov, https://clinicaltrials.gov, NCT03039088.

Are There Signs of Enthesitis in Nail Psoriasis? An Immunohistological Study of Nail Psoriasis With and Without Psoriatic Arthritis.

ABSTRACT: The concept of nail psoriasis as an entheseal-driven disease has essentially been formulated on the basis of radiological findings because it is usually not possible to obtain the tissue directly from the joints. The aim of this retrospective study was to evaluate the histological features of isolated nail psoriasis with and without distal interphalangeal psoriatic arthritis (PsA), focusing on the question as to whether the fascia and adipose tissue surrounding the apex of the nail unit genuinely show an inflammatory infiltrate. In support of the nail-enthesitis theory, an ongoing inflammatory infiltrate could be expected. An immunohistochemical study was performed to evaluate the distribution and phenotype of the inflammatory infiltrate in nail psoriasis with and without PsA. This study did not show an inflammatory infiltrate in the fascia connecting the nail to the extensor tendon. CD8 and CD4 subsets were present in equal number in the nail dermis of nail psoriasis with or without PsA, which is a similar distribution to that seen in psoriatic synovium while skin psoriasis is characterized by a dermal predominance of CD4 T lymphocytes. Because of this study and recent microanatomic studies of the normal nail unit, it is possible to move away from a purely anatomic explanation of the strong association between nail psoriasis and PsA and to propose immunological factors as contributory. This study provides support for the hypothesis that CD8+ T cells play a crucial role in the pathogenesis of nail psoriasis through a pathogenic pathway similar to that of PsA and contrasting with that of the skin.

Clinical and laboratory factors associated with bamboo spine in patients with axial spondyloarthritis: are there clues for bamboo spine?

OBJECTIVES: To analyse the clinical and laboratory factors associated with bamboo spine. METHODS: Data of patients fulfilling the 2009 ASAS classification criteria for axial spondyloarthritis, registered in the national, multicentre, longitudinal, and observational database of TReasure was analysed. Radiographs were assessed using the Bath Ankylosing Spondylitis Radiologic Index (BASRI). Data of patients with a bamboo spine (Group 1) was compared to data derived from patients with a longstanding disease of at least 15 years but no syndesmophytes (Group 2). RESULTS: Out of the 5060 patients, 1246 had eligible radiographs. There were 111 patients (8.9%) with a bamboo spine. Male sex was more common among patients with bamboo spine. The median BMI of 27.7 (25.8-31.1) in Group1 was higher than the BMI of 25.9 (22.9-29.2) in Group 2 (p<0.001). Hip arthritis, present or documented by a physician, was more common in Group 1 [(58/108 (53.7%) vs. 35/103 (34%), p=0.004]. There was a tendency towards a more prevalent enthesitis in these patients [29.1% (25/86) vs. 15.9%(11/69), p=0.054]. HLA-B27 status did not differ between groups. Smoking was more prevalent in Group 1. Multivariate logistic regression analysis revealed that male sex, body mass index, hip arthritis, and enthesitis are associated with bamboo spine in axSpA. CONCLUSIONS: Bamboo spine was more common in the male sex and associated with a delay in diagnosis, high BMI, hip involvement, and enthesitis. The constellation of increased body weight, hip arthritis, and enthesitis may imply that mechanical stress contributes to radiographic damage in the presence of chronic inflammation.

Smoking and alcohol consumption are associated with peripheral musculoskeletal involvement in patients with spondyloarthritis (including psoriatic arthritis). Results from the ASAS-PerSpA study.

BACKGROUND: An inverse association between alcohol consumption and disease activity and functional impairment has been observed in patients with spondyloarthritis (SpA). However, neither this association nor the influence of smoking has been investigated in peripheral manifestations of SpA. OBJECTIVES: The objective of this study was to analyze the association between smoking and alcohol consumption and the presence of peripheral musculoskeletal manifestations (arthritis, enthesitis or dactylitis) and to determine the specific location of these manifestations. METHODS: Patients from the worldwide cross-sectional ASAS-PerSpA study with a diagnosis of axial SpA (axSpA), peripheral SpA (pSpA) or psoriatic arthritis (PsA) according to their rheumatologist were included. Generalised linear mixed models used peripheral manifestation (or location) as a dependent variable, smoking status and alcohol consumption as fixed effects and country as a random effect. The interaction between smoking and alcohol was tested. Analyses were performed for each diagnosis (axSpA, pSpA and PsA). RESULTS: A total of 4181 patients were included. In axSpA patients, smoking was associated with a lower prevalence of any peripheral manifestation, and current alcohol consumption was associated with a lower prevalence of both current arthritis and current enthesitis. In pSpA patients, current alcohol consumption was associated with a lower prevalence of current arthritis or enthesitis. In PsA patients, a significant association was found for arthritis with smoking and for enthesitis with alcohol consumption, and current alcohol consumption was associated with a lower prevalence of current arthritis or enthesitis. CONCLUSION: Taking into account the country, smoking and alcohol are associated with a lower prevalence of peripheral manifestations.

Sex-Based Differences in Sonographic and Clinical Findings Among Patients With Psoriatic Arthritis.

OBJECTIVE: To investigate sex-based sonographic differences in patients with psoriatic arthritis (PsA). METHODS: The study population included consecutive prospectively recruited patients with PsA, as determined by the CASPAR (Classification for Psoriatic Arthritis) criteria, who underwent clinical and physical examinations, followed by a detailed ultrasound (US) evaluation (greyscale and Doppler). US evaluation included 52 joints, 40 tendons, and 14 points of entheses (Modified Madrid Sonographic Enthesis Index [MASEI] plus lateral epicondyles) performed by an experienced sonographer blinded to the clinical data. The US score was based on the summation of a semiquantitative score for synovitis, tenosynovitis, and enthesitis. The US enthesitis score was categorized into inflammatory lesions (ie, hypoechogenicity, thickening, bursitis, and Doppler) and structural lesions (ie, enthesophytes/calcifications and erosions). RESULTS: The study population of 158 patients included 70 males and 88 females. The males had higher rates of employment (P = 0.01), Psoriasis Area and Severity Index scores (P = 0.04), and mean swollen joint counts (P = 0.04). The total US score and its subcategory scores-the synovitis and tenosynovitis scores-were similar for both sexes, whereas the total enthesitis score and its subcategory score-the inflammatory enthesitis score-were significantly higher for the males compared to the females (P = 0.01 and P = 0.005, respectively). Hypoechogenicity, thickening, and enthesophytes were more prevalent in males compared to females (P < 0.05). Multivariate ordinal logistic regression models showed that male sex was associated with a higher US inflammatory enthesitis score compared to female sex (odds ratio 1.96, P = 0.02). CONCLUSION: Sonographic enthesitis was more prevalent in males compared to females with PsA. These differences were not reflected by enthesitis disease activity scores derived from clinical assessment.

Ultrasonography of heel entheses in axial spondyloarthritis patients: frequency and assessment of associated factors.

PURPOSE: Foot entheses involvement is a common manifestation of spondyloarthritis. The superiority of ultrasonography examination in foot entheses damages detection has been reported. We aimed to compare the ultrasonography findings of foot entheses between spondyloarthritis patients. and healthy controls and to identify factors associated with enthesitic heel involvement. METHODS: We conducted a cross-sectional study including 37 patients with axial spondyloarthritis (G1) and 37 healthy subjects matched by age and gender (G0). The following pro-inflammatory cytokines were measured: Interleukin (IL-)1, IL-6, IL-17, and IL-23. A blind ultrasonography of foot entheses was performed to examine calcaneal tendon (CT) and plantar fascia (PF). RESULTS: The mean age was 44.62 ± 12.31 years. Non-steroidal anti-inflammatory drugs were taken in 92% of patients. Clinical heel enthesopathy was noted in 10 patients (27%) of G1. No participant has enthesitic pain in G0. Ultrasonography changes in CT and PF were more frequent in G1 than G0 (p = 0.001 and p = 10-3, respectively). In the PF, tendon thickening was significantly higher in G1 than G0 (p = 0.03). Power Doppler in both enthesitic sites was exclusively observed in G1 (p = 10-3). Regarding associated factors, CT enthesophytes were less frequent in patients taking non-steroidal anti-inflammatory drugs continuously or having regular physical activity. PF structural damages were associated with higher erythrocyte sedimentation rate (p = 0.02), higher IL-23 level (p = 0.01), and higher disease activity (p = 0.04). CONCLUSION: Ultrasonography lesions of heel entheses were frequent in spondyloarthritis. Disease activity and inflammatory markers were higher in patients with heel enthesitis. Non-steroidal anti-inflammatory drugs intake and regular physical activity may prevent enthesophytes' occurrence.

Enthesitis in patients with psoriatic arthritis: A nationwide data from the Chinese Registry of Psoriatic Arthritis (CREPAR) / 中华医学杂志(英文版)

BACKGROUND@#The clinical features of enthesitis in patients with psoriatic arthritis (PsA) have been reported in some Western countries, but data in China are very limited. This study aimed to describe the characteristics of enthesitis in Chinese patients with PsA and compared them with those in other cohorts.@*METHODS@#Patients with PsA enrolled in the Chinese Registry of Psoriatic Arthritis (CREPAR) (December 2018 to June 2021) were included. Data including demographics, clinical characteristics, disease activity measures, and treatment were collected at enrollment. Enthesitis was assessed by the Spondyloarthritis Research Consortium of Canada (SPARCC), Maastricht ankylosing spondylitis enthesitis score (MASES), and Leeds enthesitis index (LEI) indices. A multivariable logistic model was used to identify factors related to enthesitis. We also compared our results with those of other cohorts.@*RESULTS@#In total, 1074 PsA patients were included, 308 (28.7%) of whom had enthesitis. The average number of enthesitis was 3.3 ± 2.8 (range: 1.0-18.0). More than half of the patients (165, 53.6%) had one or two tender entheseal sites. Patients with enthesitis had an earlier age of onset for both psoriasis and arthritis, reported a higher proportion of PsA duration over 5 years, and had a higher percentage of axial involvement and greater disease activity. Multivariable logistic regression showed that axial involvement (odds ratio [OR] 2.21, 95% confidence interval [CI], 1.59-3.08; P <0.001), psoriasis area and severity index (PASI) (OR: 1.03, 95% CI: 1.01-1.04; P = 0.002), and disease activity score 28-C reactive protein (DAS28-CRP) (OR: 1.25, 95% CI: 1.01-1.55; P = 0.037) were associated with enthesitis. Compared with the results of other studies, Chinese patients with enthesitis had a younger age, lower body mass index (BMI), a higher rate of positive human leukocyte antigen (HLA)-B27, more frequent dactylitis, and a higher proportion of conventional synthetic disease-modifying antirheumatic drugs' (csDMARDs) use.@*CONCLUSIONS@#Enthesitis is a common condition among Chinese patients with PsA. It is important to evaluate entheses in both peripheral and axial sites.

Prevalence and characteristics of diffuse idiopathic skeletal hyperostosis (DISH) in Italy.

PURPOSE: Diffuse idiopathic skeletal hyperostosis (DISH) is a benign condition characterized by ossification of the spine and prominent enthesopathies. Highly heterogeneous epidemiological figures have been reported in the literature, while in Italy the largest study has been conducted in 1992. The aim of our research is to contribute updated information about prevalence of DISH in Italy and to describe the clinical and radiographic characteristics associated with the disorder. MATERIAL AND METHODS: A retrospective review of lumbosacral spine, thoracic spine and pelvis radiographs was performed. Consecutive patients visiting the emergency department of our Institution over 3 years were enrolled. Presence of DISH was evaluated applying the Resnick and Niwayama criteria. Clinical and radiological features were also assessed. RESULTS: We included 1012 individuals (60.6% women), and DISH was present in 130 cases. The overall prevalence of DISH was 12.8% (95% CI 10.8-15.1), with higher figures in the male sample (16.8%) than in females (10.3%). In binary logistic regression adjusted for age, BMI (OR 1.50, p < 0.001) diabetes (OR 1.85, p = 0.003), hypertension (OR 2.04, p = 0.007) ischiopubic enthesopathy (OR 7.08, p < 0.001), iliac crest enthesopathy (OR 4.63, p < 0.001) and greater trochanter enthesopathy (OR 3.51, p < 0.001), were significantly associated with the condition. CONCLUSION: The prevalence of DISH observed in our study is consistent with previous literature, and we confirm that the disorder is more frequently retrieved in men and that it is associated with the presence of metabolic disorders and pelvic enthesopathy. Knowledge about the epidemiology and characteristics of DISH is needed to properly identify the condition.

Effectiveness of Disease-Modifying Antirheumatic Drugs for Enthesitis in a Prospective Longitudinal Psoriatic Arthritis Cohort.

OBJECTIVE: Our objective was to assess the effectiveness of conventional and targeted disease-modifying antirheumatic drugs (cDMARDs and tDMARDs, respectively) in treating enthesitis in psoriatic arthritis (PsA). METHODS: Patients with active enthesitis, defined as ≥ 1 tender entheses (of the 29 enthesis sites included in the Spondyloarthritis Research Consortium of Canada Enthesitis Index, the Leeds Enthesitis Index, and the Maastricht Ankylosing Spondylitis Enthesitis Score), who were enrolled in a large PsA cohort were included. Medications at baseline were classified into 3 mutually exclusive categories: (1) no treatment or nonsteroidal antiinflammatory drugs (NSAIDs) only; (2) cDMARDs ± NSAIDs; and (3) tDMARDs ± cDMARDs/NSAIDs. Complete resolution of enthesitis (no tender enthesis) at 12 months was the primary outcome. Logistic regression models were developed to determine the association between medication category and enthesitis resolution. RESULTS: Of the 1270 patients studied, 628 (49.44%) had enthesitis. Of these, 526 patients (51.71% males; mean [SD] age 49.02 [13.12] years; mean enthesitis score 2.13 [2.16]; median enthesitis score 2 [IQR 1-2]), with adequate follow-up were analyzed. Complete resolution of enthesitis was noted in 453 (86.12%) patients, within a mean period of 8.73 (3.48) months from baseline. In the regression analysis, though not significant, DMARDs (categories II and III) had higher odds ratios (ORs) compared to category 1 for resolution of enthesitis. Enthesitis resolution was associated with lower joint activity (OR 0.97, 95% CI 0.95-0.99; P = 0.01) and male sex (OR 1.66, 95% CI 0.97-2.84; P = 0.06). CONCLUSION: Resolution of enthesitis was observed in 86% of patients in an observational setting regardless of the medication used. Future effectiveness studies may warrant evaluation of enthesitis using advanced imaging.

The impact of psoriasis on the clinical characteristics, disease burden and treatment patterns of peripheral spondyloarthritis.

OBJECTIVES: To evaluate the clinical characteristics, disease burden, and treatment patterns of peripheral spondyloarthritis (pSpA) patients with and without psoriasis using data from the ASAS-perSpA study. METHODS: We included 433 patients who had a diagnosis of pSpA according to the rheumatologist's diagnosis from the ASAS-PerSpA study. The presence of a personal history of psoriasis was defined as the presence of signs of psoriasis at physical examination or the presence of psoriatic nail dystrophy, including onycholysis, pitting and hyperkeratosis, or a history of psoriasis diagnosed by a physician. Clinical characteristics, patient-reported outcomes and treatment pattern were compared between subgroups with and without psoriasis. RESULTS: A total of 83 patients (19.2%) had a personal history of psoriasis. Patients with psoriasis were older (48.4 vs 43.2 years) and had a longer diagnostic delay (7.4 vs 3.5 years), a higher frequency of dactylitis (36.1 vs 20.0%) and enthesitis (65.1 vs 55.4%) than patients without psoriasis. A longer diagnostic delay (odds ratio [OR] = 1.06 [95% CI 1.01, 1.11]), lower odds for HLA-B27 positivity (OR = 0.31 [95% CI 0.15, 0.65]) and higher odds for enthesitis (OR = 2.39 [95% CI 1.16, 4.93]) were associated with the presence of psoriasis in a multivariable regression analysis. While patient-reported outcomes were comparable between groups, a higher use of biologic DMARDs was observed in patients with vs without psoriasis. CONCLUSION: The presence of psoriasis has an impact on clinical characteristics of pSpA. pSpA patients without psoriasis were less frequently treated with biologic DMARDs despite similar disease burden as compared with patients with psoriasis.

Psoriatic arthritis: Ultrasound peculiarities with particular emphasis on enthesitis.

The prevalence of psoriatic arthritis among patients with psoriasis has a marked variability with ethnic and geographic variations. Inflammatory changes associated with psoriatic arthritis include bone erosion, tenosynovitis, and synovial hypertrophy, but enthesitis is considered the hallmark. Both X-ray and magnetic resonance imaging (MRI) are usefull in the diagnosis of psoriatic arthritis, but ultrasonography is the best imaging modality to assess entheses. Ultrasound findings of enthesitis include a loss of the regular fibrillar architecture, hypoechoic thickening, hypervascularization of tendons, ligaments, and joint capsules at their bony attachment, bony changes (including irregularities and erosions). Ultrasound has also proved the ability to detect inflammatory subclinical findings and to be useful in the follow-up of therapies.

Defining imaging sub-phenotypes of psoriatic arthritis: integrative analysis of imaging data and gene expression in a PsA patient cohort.

OBJECTIVES: To define imaging sub-phenotypes in patients with PsA; determine their association with whole blood gene expression and identify biological pathways characterizing the sub-phenotypes. METHODS: Fifty-five patients with PsA ready to initiate treatment for active disease were prospectively recruited. We performed musculoskeletal ultrasound assessment of the extent of inflammation in the following domains: synovitis, peritenonitis, tenosynovitis and enthesitis. Peripheral whole blood was profiled with RNAseq, and gene expression data were obtained. First, unsupervised cluster analysis was performed to define imaging sub-phenotypes that reflected the predominant tissue involved. Subsequently, principal component analysis was used to determine the association between imaging-defined sub-phenotypes and peripheral blood gene expression profile. Pathway enrichment analysis was performed to identify underlying mechanisms that characterize individual sub-phenotypes. RESULTS: Cluster analysis revealed three imaging sub-phenotypes: (i) synovitis predominant [n = 31 (56%)]; (ii) enthesitis predominant [n = 13 (24%)]; (iii) peritenonitis predominant [n = 11 (20%)]. The peritenonitis-predominant sub-phenotype had the most severe clinical joint involvement, whereas the enthesitis-predominant sub-phenotype had the highest tender entheseal count. Unsupervised clustering of gene expression data identified three sub-phenotypes that partially overlapped with the imaging sub-phenotypes suggesting biological and clinical relevance of these sub-phenotypes. We therefore characterized enriched differential pathways, which included: immune system (innate system, B cells and neutrophil degranulation), complement system, platelet activation and coagulation function. CONCLUSIONS: We identified three sub-phenotypes based on the predominant tissue involved in patients with active PsA. Distinct biological pathways may underlie these imaging sub-phenotypes seen in PsA, suggesting their biological and clinical importance.

Enthesitis in patients with psoriatic arthritis and axial spondyloarthritis - data from the Danish nationwide DANBIO registry.

OBJECTIVE: To explore the registration, pattern and burden of clinical enthesitis among routine-care patients with psoriatic arthritis (PsA) and axial spondyloarthritis (axSpA) in the Danish nationwide DANBIO registry. METHODS: In patients with PsA and axSpA in DANBIO, prospectively registered data from 2010 to 2020 on clinical entheseal assessment using SPARCC score were compared with demographic, clinical and patient-reported-outcome (PRO) data. RESULTS: 6582 PsA and 5547 axSpA patients had their first registration in DANBIO in 2010 or later ("incident cohort"). At these registrations, 1037 (16%) PsA and 1188 (21%) axSpA patients had entheseal assessments, with ≥1 enthesitis being found in 66% and 39%, respectively. Mean enthesitis scores were 2.5 (PsA) and 1.3 (axSpA). Most common sites were: Achilles tendon (right/left/symmetrical: PsA:24.4%/23.3%/17.1%; axSpA:10.4%/10.6%/8.0%), lateral epicondyle (PsA:22.2%/20.1%/16.2%; axSpA:.4%/9.7%/7.6%), plantar fascia (PsA:17.1%/17.0%/12.6%; axSpA:10.4%/10.6%/8.0%), greater trochanter (PsA:14.2%/15.4%/11.7%; axSpA:9.9%/11.2%/8.2%). Enthesitis was more frequent in women (PsA/axSpA 61%/62%) than men (39%/37%). Patients with vs without enthesitis had higher overall burden (higher physician global, swollen/tender joint counts, pain, fatigue, patient global; fewer in patient-acceptable-symptom-state (PASS)) (all p < 0.05). Comparable demographic, clinical and PRO-results in patients with missing entheseal assessments, support the data being representative. In an "overall" cohort of all patients with ≥1 entheseal assessments after 2010, results on enthesitis were comparable. CONCLUSION: Entheseal assessments were only performed at a minority of clinical visits. Clinical enthesitis was frequent, particularly in women, often symmetrical and associated with a higher physician- and patient-reported disease burden in patients with PsA and axSpA treated in routine practice, emphasizing the need for systematic assessment in routine care.

Iliotibial band enthesopathy: an unusual cause of lateral knee pain post total knee replacement.

Iliotibial band (ITB) pathology is one of the main causes of lateral knee pain. The enthesopathy of the ITB at its insertion post total knee replacement (TKR) is a rare cause of lateral knee pain. We describe a series of cases of ITB enthesopathy with sonographic findings and management.