Serum calprotectin as an inflammatory marker in psoriatic arthritis patients: Relation to disease activity and musculoskeletal ultrasound findings.

Psoriatic arthritis (PsA) is a chronic inflammatory arthritis associated with psoriasis. The use of inflammatory markers can be disappointing in PsA since they are elevated in only about half of the patients. This study aimed to measure serum calprotectin level in PsA patients and to assess its association with disease activity in PsA (DAPSA) and musculoskeletal ultrasound findings. The study included 50 PsA patients and 30 controls. All subjects underwent medical history, musculoskeletal examination, hand and wrist joints ultrasound, and laboratory assessment. The mean age of patients was 41.04±11.8 years with female: male ratio of 3:2, and the median duration of arthritis 2 years (1-4 years) and DAPSA 25 years (3-84 years). The most common finding in patients by ultrasound was synovial hypertrophy in wrist joint (32%) followed by hand joints (28%). Patients' serum calprotectin level was significantly higher (174.2 ng/ml; ranged 127.5-282.6 ng/ml) than controls 41.4 ng/ml; ranged 19.9-59.8 ng/ml) (p < 0.001). Serum calprotectin predicted the occurrence of PsA at cutoff >106.4 ng/ml (with sensitivity 98%, and specificity 86.6%; p=0.001) and predicted synovial hypertrophy in hand joints at cutoff >258.9 ng/ml (with sensitivity 71%, and specificity 83%). There was a significant relation between serum calprotectin with synovial hypertrophy (p=0.004), osteophytes (p < 0.0001), nail affection (p=0.03) and erosions (p=0.01). Serum calprotectin is a more potential predictor for PsA (p < 0.0001) compared to erythrocyte sedimentation rate (p=0.005) and C-reactive protein (p=0.001). In conclusion, serum calprotectin level is significantly high in PsA patients. It is associated with small hand joints synovitis and nail changes. This makes it a promising biomarker for defining patients with suspected PsA who do not meet specific disease criteria.

Deep learning-based classification of erosion, synovitis and osteitis in hand MRI of patients with inflammatory arthritis.

OBJECTIVES: To train, test and validate the performance of a convolutional neural network (CNN)-based approach for the automated assessment of bone erosions, osteitis and synovitis in hand MRI of patients with inflammatory arthritis. METHODS: Hand MRIs (coronal T1-weighted, T2-weighted fat-suppressed, T1-weighted fat-suppressed contrast-enhanced) of rheumatoid arthritis (RA) and psoriatic arthritis (PsA) patients from the rheumatology department of the Erlangen University Hospital were assessed by two expert rheumatologists using the Outcome Measures in Rheumatology-validated RA MRI Scoring System and PsA MRI Scoring System scores and were used to train, validate and test CNNs to automatically score erosions, osteitis and synovitis. Scoring performance was compared with human annotations in terms of macro-area under the receiver operating characteristic curve (AUC) and balanced accuracy using fivefold cross-validation. Validation was performed on an independent dataset of MRIs from a second patient cohort. RESULTS: In total, 211 MRIs from 112 patients (14 906 region of interests (ROIs)) were included for training/internal validation using cross-validation and 220 MRIs from 75 patients (11 040 ROIs) for external validation of the networks. The networks achieved high mean (SD) macro-AUC of 92%±1% for erosions, 91%±2% for osteitis and 85%±2% for synovitis. Compared with human annotation, CNNs achieved a high mean Spearman correlation for erosions (90±2%), osteitis (78±8%) and synovitis (69±7%), which remained consistent in the validation dataset. CONCLUSIONS: We developed a CNN-based automated scoring system that allowed a rapid grading of erosions, osteitis and synovitis with good diagnostic accuracy and using less MRI sequences compared with conventional scoring. This CNN-based approach may help develop standardised cost-efficient and time-efficient assessments of hand MRIs for patients with arthritis.

Anatomical pattern of entheseal and synovial fibroblast activation in patients with psoriasis and its risk of developing psoriatic arthritis.

OBJECTIVES: To assess the presence and anatomical distribution of activated fibroblasts in the joints and entheses of patients with psoriasis with arthralgia and to test how fibroblast activation visualised by 68gallium-labelled fibroblast activation protein inhibitor-04 (68Ga-FAPI-04)-positron emission tomography (PET)/CT correlates with clinical tenderness, musculoskeletal ultrasound findings and progression to psoriatic arthritis (PsA). METHODS: We conducted a prospective cohort study in patients with psoriasis and arthralgia who underwent clinical and ultrasound evaluation and whole-body PET/CT imaging with 68Ga-FAPI-04. 68Ga-FAPI-04 uptake at synovial and entheseal sites was assessed by maximal standardised uptake values (SUVmax) and PET/CT Joint Index (JI); logistic regression models were used to investigate its correlation with clinical and ultrasound findings. Survival analyses were performed on patients with at least 6 months of follow-up. RESULTS: 36 patients with psoriasis were enrolled. 68Ga-FAPI-04 uptake was found in 318 (7.9%) joints and 369 (7.3%) entheses in 29 (80.6%) participants, with a mean SUVmax (SD) of 3.2 (1.8) for joints and 2.9 (1.6) for entheses. Large joints and the lower limbs were predominantly affected. A significant positive relationship was found between 68Ga-FAPI-04-PET/CT signal intensity and the 68 tender joint count (SUVmax: p<0.001; PET/CT-JI: p<0.001) and tender entheses count (SUVmax: p<0.001; PET/CT-JI: p=0.002). No correlations were found with ultrasound findings (SUVmax: p=0.969; PET/CT-JI: p=0.720). Patients with relevant synovio-entheseal 68Ga-FAPI-04 uptake showed a statistically significant higher risk of developing PsA (p=0.02), independent of ultrasound findings. CONCLUSIONS: Patients with psoriasis presenting with arthralgia show localised signs of resident tissue activation in joints and entheses, which are associated with higher risk of developing PsA.

Evaluation of the Possibility of Axial Psoriatic Arthritis Patients Meeting Classification Criteria for Axial Spondyloarthritis and Ankylosing Spondylitis.

The objective of the study was to analyze whether axial psoriatic arthritis (axPsA) patients meet classification criteria for axial spondyloarthritis (axSpA) and ankylosing spondylitis (AS). A total of 104 patients (66 men and 38 women) with PsA according to CASPAR criteria were examined, all patients had back pain. Patients were evaluated for presence of inflammatory back pain (IBP) by ASAS criteria. Back pain not meeting the ASAS criteria was taken to be chronic back pain (chrBP). Patients underwent hands, feet and pelvis, cervical spine and lumbar spine X-rays. Erosions, osteolysis, and juxta-articular new bone formation were evaluated. Definite radiographic sacroiliitis (d-rSI) was defined as bilateral grade ≥ 2 or unilateral grade ≥ 3. Nineteen patients without d-rSI underwent sacroiliac joints MRI. Ninety-three patients underwent HLA B27 examination. The number of patients who met the criteria for axSpA (ASAS) and the modified New York (mNY) criteria for AS was determined. IBP was identified in 67 (64.4%) patients; chrBP, in 37 (35.6%) patients; 31 (29.8%) patient were of older age (over 40) at the onset of IBP/chrBP; 57 (58.8%) patients had d-rSI; 6 (31.6%) patients had MRI-SI; syndesmophytes were detected in 57 (58.8%) cases. Among 40 patients without d-rSI, 19 (47.5%) had syndesmophytes. In 38/97 (39.2%) patients d-rSI was detected along with syndesmophytes, while 19/97 (19.6%) patients had isolated d-rSI without spondylitis, and 19/97 (19.6%) patients had isolated syndesmophytes without d-rSI. HLA B27 was present in 28 (30.1%) cases. 51 (55.4%) patients met criteria for axSpA. Forty-one (44.6%) patients did not meet criteria for axSpA; however, 27 (65.9%) of them had syndesmophytes. Forty-eight (48.5%) PsA patients met mNY criteria for AS. Among these patients, a set of specific features was revealed: 18 (37.5%) had no IBP, 18 (37.5%) were of older age (over 40) at the onset of IBP/chrBP, 34 (70.8%) had dactylitis, 38 (79.2%) had erosive polyarthritis, 23 (48.8%) had juxta-articular new bone formation, 14 (30.2%) had osteolysis, 23 (48.9%) had "chunky" non-marginal syndesmophytes, and 40 (82.6%) had nail psoriasis; 28 (66.6%) patients were HLA-B27 negative. Forty-five percent of axPsA patients do not meet criteria for axSpA. Characteristic features have been identified to differentiate axPsA from AS.

Determinants of radiographic progression in early psoriatic arthritis: insights from a real-world cohort.

OBJECTIVE: Persistent articular inflammation in psoriatic arthritis (PsA) is associated with radiographic damage. Despite advances in diagnosis and therapy, radiographic structural damage remains prevalent in PsA. To elucidate this topic, we studied which baseline clinical characteristics determine radiographic progression. METHODS: For this analysis, data were used from DEPAR (Dutch South West Psoriatic Arthritis) Study, a real-world cohort of patients with newly diagnosed PsA. Radiographic changes were assessed using the modified Total Sharp/van der Heijde Score (mTSS) for PsA. Univariable-multivariable mixed-effects negative binomial regression analysis was applied to define baseline predictors for radiographic progression over time. RESULTS: The study included 476 patients with early PsA with 1660 hand and feet radiographs from four different time points (baseline, first, second and third year). The progressive group (n=71) had a higher mTSS compared with the non-progressive group (n=405) at diagnosis (17 (3-36) vs 0 (0-1)). A comparison of the two groups revealed that the progressive group had significantly older (59 (12) vs 49 (13)) and a higher rate of the presence of swollen joints (93% vs 78%) at diagnosis. Multivariable analysis identified age (incidence rate ratio (IRR)=1.10, p=0.000), sex (female) (IRR=0.48, p=0.043) and baseline mTSS (IRR=1.11, p=0.000) as significant determinants of radiographic change over time. For the progressive subset, additionally, the multivariable analysis highlighted baseline Disease Activity in PSoriatic Arthritis (IRR=1.05, p=0.006) and swollen joint count (IRR=1.07, p=0.034) as predictors. CONCLUSIONS: According to this real-world cohort, patients with early PsA exhibit minimal radiographic progression under current treatment protocols. This study indicates that while old age and initial radiographic damage predict progression, female sex confers a protective effect on it. Furthermore, disease activity score and swollen joints emerged as predictors for radiographic changes during the follow-up in progressive patients.

Ultrasonographic and power doppler parameters of nails fail to differentiate between onychodystrophy in patients with psoriasis vulgaris or psoriatic arthritis.

BACKGROUND: Nail involvement is frequent in patients with psoriasis (Pso) and psoriatic arthritis (PsA) and there is a relationship between nail involvement and inflammation of the enthesis. The main objective of the present study is to describe the ultrasound findings and clinical characteristics of nails from patients with psoriasis and psoriatic arthritis with and without nail dystrophy. METHODS: A cross-sectional study including consecutive patients with PsO and PsA was carried out. The study patients were divided into 4 groups, totaling 120 participants. Group 1: patients with psoriasis vulgaris and clinically normal nails; Group 2: patients with psoriasis vulgaris and onychodystrophy; Group 3: patients with psoriatic arthritis and clinically normal nails; Group 4: patients with psoriatic arthritis and onychodystrophy; All patients were submitted to dermatological and rheumatological clinical analysis. Ultrasound examinations was performed by a single examiner, blinded to all clinical data, with ultrasound high resolution, in B-mode or gray-scale (GS), Power Doppler (PD) and Spectral Doppler. RESULTS: A significant difference was found between the groups regarding the variable Psoriasis Area and Severity Index (PASI) (p = 0.008) and body surface area (BSA) (p = 0.005), with patients with psoriatic arthritis having lower PASI and BSA compared to patients with only cutaneous psoriasis. A positive relationship was found with the average ultrasound thickness of the nail bed and the Nail Psoriasis Severity Index (NAPSI) in correlation analysis (rho = 0.344). When we grouped patients with psoriasis and psoriatic arthritis, there was no significant difference between the cutaneous psoriasis groups and the psoriatic arthritis groups in terms of nail plate GS (p = 0.442), nail bed PD (p = 0.124). CONCLUSION: Greater nail bed thickness indicates early psoriatic nail disease, as confirmed in our study correlating NAPSI with nail bed thickness. Ultrasonography is a low-cost exam, promising in the evaluation, showing that the ultrasound grayscale is consistent with those who have dystrophic nails, but it can't distinguish psoriasis from psoriatic arthritis, even in those with nail dystrophy.

Ultrasound Assessment of Psoriatic Arthritis Patients With Clinically Normal Nails and Evaluation of its Correlation With the Disease Activity: A Case-Control Study.

OBJECTIVES: Nail unit is one of the targets of ultrasound (US) assessment. We aimed to compare ultrasound parameters of clinically normal nail unit in psoriatic arthritis (PsA) patients with healthy controls (HC) and evaluate their correlations with disease activity. METHODS: This was a cross-sectional study including patients with PsA and matched HC. Tender (TJC) and swollen joint count (SJC), Psoriasis Area and Severity Index (PASI), and Disease Activity in Psoriatic Arthritis (DAPSA) were collected in PsA patients. Patients underwent US assessment of fingernails with a study of morphological changes and measurement of the thickness of nail bed (NBT), nail plate (NPT), and adjacent skin (ST). Correlation between nail unit parameters and disease activity was studied. RESULTS: We evaluated 22 PsA patients (219 nails) and 21 HC (210 nails). Mean DAPSA was 21.56 ± 14.36 and mean PASI was 2.19 ± 3.8. PsA patients had more US morphological changes than HC (16.89 vs 3.33%, P = .03). NPT comparison between identical fingernails of PsA and HC did not reveal significant difference. However, NBT was significantly higher in HC (1.77 vs 2.07 mm, P = .027) as well as ST (2.26 vs 2.59 mm, P = .003). TJC and ST were positively correlated (r = .46, P = .03). No correlation was noted between disease activity scores and NPT, NBT, or ST in PsA patients. In biologic parameters, ESR was negatively correlated with ST (r = -.41, P = .05). CONCLUSIONS: Nail bed and adjacent skin US morphological changes were contributive to distinguish psoriatic from healthy nails. Adjacent skin thickness measurement was positively correlated with TJC and ESR, suggesting that it could be used as an indicator of disease activity in PsA.

Hematological indices in psoriatic enthesopathy: relation to clinical and ultrasound evaluation.

BACKGROUND: Enthesopathy is considered a crucial aspect of assessment and outcome in psoriatic arthritis (PsA). Musculoskeletal ultrasound (MSUS) is a critical tool for accurately detecting enthesitis. Recent research focuses on identifying simple biomarkers for detecting and monitoring psoriatic enthesopathy. Red cell distribution width (RDW), mean platelet volume (MPV), and neutrophil/lymphocyte ratio (NLR) are components of a complete blood count (CBC) and are reliable bio-inflammatory markers in various rheumatic diseases. AIM OF WORK: To measure MPV, RDW, and NLR in psoriatic enthesopathy and determine their relationship to disease activity and MSUS findings. PATIENTS AND METHODS: This study focused on 30 people with psoriatic arthritis (PsA) as per CASPAR criteria, along with 20 control subjects. Enthesopathy was evaluated clinically using the Leeds Enthesitis Index (LEI). The modified Disease Activity Index of Psoriatic Arthritis (DAPSA28) was calculated, and RDW, MPV, NLR, CRP, and ESR were measured. Each enthesis in LEI was radiologically assessed using plain radiography and MSUS according to OMERACT definitions. RESULTS: There was a significant relationship between clinical tenderness, the presence of enthesophytes on plain radiography, and MSUS findings at entheses sites (p < 0.001 for each). Psoriatic patients had higher levels of RDW and MPV (p < 0.001 and 0.01, respectively) than controls, with no significant differences in NLR (p = 0.189) between the two groups. RDW and MPV levels were positively correlated with the DAPSA28 score. CONCLUSION: Monitoring PsA disease activity can be improved by considering RDW and MPV as reliable indicators and using them to screen for psoriatic enthesopathy with MSUS indices. Key points • Clinically identifying enthesitis in patients with PsA can be challenging. Imaging MSUS indices hold promise for objective analysis, but there is no consensus on which indices to use in clinical trials and daily practice. • Patients with psoriatic enthesopathy have higher RDW and MPV levels, which are positively correlated with DAPSA28 score. • RDW and MPV can be considered in the turn of improved screening of psoriatic enthesopathy with MSUS scores.

High prevalence of radiographic erosions in early, untreated PsA: results from the SpARRO cohort.

AIMS: To investigate the prevalence and distribution of bone erosions in an early psoriatic arthritis (PsA) population using conventional radiography (CR) and to explore the agreement between CR and ultrasound (US) detected bone erosions. METHODS: Newly diagnosed, treatment naïve PsA patients fulfilling the ClASsification for Psoriatic Arthritis (CASPAR) classification criteria of ≤5 years symptom duration were recruited as part of the Leeds Spondyloarthropathy Register for Research and Observation and underwent CR and US examination of hands and feet. RESULTS: Overall, 4655 hand and feet joints were assessed in 122 patients. CR erosions were detected in 24.6% (n=30) with lowest prevalence seen below 8 months of symptoms (17.5% vs 24.3%>24 months). The number of erosions was higher on CR (1.55% (63/4,655); US 1.04% (34/3,270)), with 5th metatarsophalangeal (MTP) joint being the most affected site in both CR (5.21% (11/211)) and US (7.14% (15/210)). Erosions in CR were more evenly distributed compared with US where three-quarters of the total number of bone erosions were detected in wrists, second metacarpophalangeal (MCP) and fifth MTP joints. Most joints had almost perfect prevalence-adjusted bias-adjusted kappa values ranging from 0.91 to 1. CONCLUSIONS: Erosions were seen in a quarter of patients with newly diagnosed, untreated PsA with a declining trend around the 8-month symptom duration cut-off. High levels of agreement between CR and US were seen with CR detecting more erosions. A focused US assessment of the wrist, second MCP and fifth MTP joints may be useful to detect bone erosions in early PsA.

Validation and incorporation of digital entheses into a preliminary GLobal OMERACT Ultrasound DActylitis Score (GLOUDAS) in psoriatic arthritis.

OBJECTIVES: The main objective was to generate a GLobal OMERACT Ultrasound DActylitis Score (GLOUDAS) in psoriatic arthritis and to test its reliability. To this end, we assessed the validity, feasibility and applicability of ultrasound assessment of finger entheses to incorporate them into the scoring system. METHODS: The study consisted of a stepwise process. First, in cadaveric specimens, we identified enthesis sites of the fingers by ultrasound and gross anatomy, and then verified presence of entheseal tissue in histological samples. We then selected the entheses to be incorporated into a dactylitis scoring system through a Delphi consensus process among international experts. Next, we established and defined the ultrasound components of dactylitis and their scoring systems using Delphi methodology. Finally, we tested the interobserver and intraobserver reliability of the consensus- based scoring systemin patients with psoriatic dactylitis. RESULTS: 32 entheses were identified in cadaveric fingers. The presence of entheseal tissues was confirmed in all cadaveric samples. Of these, following the consensus process, 12 entheses were selected for inclusion in GLOUDAS. Ultrasound components of GLOUDAS agreed on through the Delphi process were synovitis, tenosynovitis, enthesitis, subcutaneous tissue inflammation and periextensor tendon inflammation. The scoring system for each component was also agreed on. Interobserver reliability was fair to good (κ 0.39-0.71) and intraobserver reliability good to excellent (κ 0.80-0.88) for dactylitis components. Interobserver and intraobserver agreement for the total B-mode and Doppler mode scores (sum of the scores of the individual abnormalities) were excellent (interobserver intraclass correlation coefficient (ICC) 0.98 for B-mode and 0.99 for Doppler mode; intraobserver ICC 0.98 for both modes). CONCLUSIONS: We have produced a consensus-driven ultrasound dactylitis scoring system that has shown acceptable interobserver reliability and excellent intraobserver reliability. Through anatomical knowledge, small entheses of the fingers were identified and histologically validated.

From Psoriasis to Psoriatic Arthritis: Ultrasound Insights Connecting Psoriasis with Subclinical Musculoskeletal Inflammation and the Path to Psoriatic Arthritis.

PURPOSE OF REVIEW: This review summarizes the literature about the transition from psoriasis to psoriatic arthritis (PsA), focusing on musculoskeletal ultrasound (MSUS) for detecting subclinical inflammation and its role in diagnosis and triage of high-risk patients. RECENT FINDINGS: MSUS effectively detects subclinical musculoskeletal inflammation in patients with psoriasis; however, some of these lesions are non-specific and can be found in healthy individuals. Preliminary evidence suggest that subclinical sonographic findings may predict progression to PsA in psoriasis patients. MSUS can also improve referrals' accuracy and its integration in the PsA classification criteria may improve early PsA detection. MSUS is a valuable tool for detecting subclinical abnormalities in psoriasis patients, which indicate an increased likelihood of progressing to PsA. Its integration into referral protocols and clinical use could improve PsA diagnosis. We propose an MSUS-inclusive algorithm for PsA referrals and triage, which requires validation. The potential of early intervention in reducing PsA progression in psoriasis patients with subclinical inflammation remains to be established.

Power Doppler signal at the enthesis and bone erosions are the most discriminative OMERACT ultrasound lesions for SpA: results from the DEUS (Defining Enthesitis on Ultrasound in Spondyloarthritis) multicentre study.

OBJECTIVES: To assess, in spondyloarthritis (SpA), the discriminative value of the Outcome Measures in Rheumatology (OMERACT) ultrasound lesions of enthesitis and their associations with clinical features in this population. METHODS: In this multicentre study involving 20 rheumatology centres, clinical and ultrasound examinations of the lower limb large entheses were performed in 413 patients with SpA (axial SpA and psoriatic arthritis) and 282 disease controls (osteoarthritis and fibromyalgia). 'Active enthesitis' was defined as (1) power Doppler (PD) at the enthesis grade ≥1 plus entheseal thickening and/or hypoechoic areas, or (2) PD grade >1 (independent of the presence of entheseal thickening and/or hypoechoic areas). RESULTS: In the univariate analysis, all OMERACT lesions except enthesophytes/calcifications showed a significant association with SpA. PD (OR=8.77, 95% CI 4.40 to 19.20, p<0.001) and bone erosions (OR=4.75, 95% CI 2.43 to 10.10, p<0.001) retained this association in the multivariate analysis. Among the lower limb entheses, only the Achilles tendon was significantly associated with SpA (OR=1.93, 95% CI 1.30 to 2.88, p<0.001) in the multivariate analyses. Active enthesitis showed a significant association with SpA (OR=9.20, 95% CI 4.21 to 23.20, p<0.001), and unlike the individual OMERACT ultrasound lesions it was consistently associated with most clinical measures of SpA disease activity and severity in the regression analyses. CONCLUSIONS: This large multicentre study assessed the value of different ultrasound findings of enthesitis in SpA, identifying the most discriminative ultrasound lesions and entheseal sites for SpA. Ultrasound could differentiate between SpA-related enthesitis and other forms of entheseal pathology (ie, mechanical enthesitis), thus improving the assessment of entheseal involvement in SpA.

Ultrasonographic Evaluation of Nail Involvement in Patients With Axial Spondyloarthritis.

OBJECTIVES: This study aimed to evaluate the nail units of patients with axial spondyloarthritis (ax-SpA) using ultrasound and to identify any subclinical changes. We also aimed to examine the relationship between clinical enthesitis scores and nail involvement in patients with ax-SpA. METHODS: The study included 40 patients with ax-Spa, 40 patients with psoriatic arthritis (PsA), and 40 healthy controls. The thickness of the nail plates, morphological changes, the thickness of the proximal nail units, the thickness of the nail beds, and power Doppler signal intensities were evaluated and compared. Maastricht Ankylosing Spondylitis Enthesitis Score and Spondyloarthritis Research Consortium of Canada Enthesitis Index were also evaluated in patients with ax-SpA. RESULTS: There was no significant difference between the thickness of the nail plates of the three groups (P > .05). The first nail bed thickness of ax-SpA cases was significantly higher than the control group (P = .046), and the fourth and fifth nail proximal unit thicknesses of the control group were significantly lower than the ax-SpA and PsA groups (P = .023, P = .017). We also found that the Wortsman scores of the cases with PsA were significantly higher than the ax-SpA and control groups (P = .0001). CONCLUSION: The thickness of the proximal nail unit adjacent to the insertion of the digital extensor tendon, which is considered as the enthesis area, is similar to the patients with PsA in patients with ax-SpA, especially in the fourth and fifth fingers compared to the control group. On the other hand, almost no structural changes in nail plates were observed in patients with ax-SpA group.

Bony proliferations in rheumatoid arthritis, psoriatic arthritis and osteoarthritis using high-resolution peripheral quantitative computed tomography-A systematic literature review.

PURPOSE: Osteoarthritis (OA), rheumatoid arthritis (RA), and psoriatic arthritis (PsA) can all lead to the formation of bony proliferations (BP). This systematic review aimed to examine the characteristics of BPs in patients with RA, PsA, OA, and healthy controls (HC) using high-resolution peripheral quantitative computed tomography (HR-pQCT). Secondarily, we examined any treatment-related effect on BP number and size. METHODS: A systematic literature search was conducted in PubMed and Embase, and a total of 15 studies were included. RESULTS: Seven studies demonstrated a disease-specific variation in BP location. One study showed no difference in the number of BPs between patients with PsA and OA. The number of BPs was greater in patients with PsA compared to RA in one study, and to HC in another study, while one study documented no difference in the number of BPs between patients with RA and HC. Five studies showed larger BPs in patients with PsA compared to HC, and one study larger BPs in patients with PsA compared to RA. One study showed no difference in BP size between patients with PsA and OA. Secukinumab may have a potential effect on arresting BP progression. Otherwise, no other treatment was reported to influence BP size and progression. No standard definitions or measurement techniques for BPs using HR-pQCT have been identified. CONCLUSION: BPs showed disease-specific variations in location, size, and number. Results regarding treatment-related effects are sparse. An agreement on the definition and measurement technique for BPs using HR-pQCT is warranted for diagnostic accuracy, disease comparability, and monitoring potential.

The activity of psoriatic arthritis with axial involvement correlates with the PsAID12.

OBJECTIVE: To determine the impact of the disease in patients with PsA in daily clinical practice and to evaluate its relationship with its axial activity. METHODS: A cross-sectional study was conducted in consecutive patients attended from January 2021 to December 2021 who met the CASPAR criteria, with clinical of inflammatory back pain and positive axial imaging, with or without peripheral involvement. Demographic, clinical, analytical data, HAQ index, PsAID12 and activity index (BASDAI and ASDAS-PCR) were also collected. Patients were divided into two groups, those with high impact and those with low impact according to PsAID results. Continuous variables are shown as median (Q1-Q3) and categorical variables as percentages and frequencies. RESULTS: Of the 269 patients evaluated with PsA, 72 patients with axial involvement were included, 40 men (55.6%), with a median age of 54.1 years and disease duration of 7 years. 28.3% of the patients were obese and serum CRP level was 0.45 mg/dl (0.08-1.10). BASDAI was 4.2 (2.0-6.2) and ASDAS-PCR was 2.4 (1.5-3.2), which translates into 39.6% of patients in low activity or remission. The median PsAID total score was 3.9 (1.6-5.4), evaluated in 61 patients. The patients who achieved a PsAID12 ≤ 4 were 63%, mostly men and with lower CRP levels than PsAID ≥ 4 patients. In addition, low impact measured by the PsAID12 was associated with low results in BASDAI and ASDAS-PCR. CONCLUSIONS: Axial involvement reflected lower impact of the disease measured by PsAID12 and it is correlated with low activity measured by BASDAI and ASDAS-PCR.

Cerebral Tumefactive Inflammatory Lesion Occurrence During Ixekizumab Treatment in a Patient With Active Psoriatic Arthritis.

INTRODUCTION: Ixekizumab is an anti-interleukin-17A (IL-17A) humanized monoclonal antibody approved for the treatment of moderate-to-severe plaque psoriasis, active psoriatic arthritis, and ankylosing spondylitis. Central nervous system inflammatory manifestations are atypical during therapy with IL-17A inhibitors, with only one case of myelitis described to date. CASE REPORT: A 72-year-old man with a medical history of active psoriatic arthritis was admitted to our department owing to the acute onset of left face numbness 1 month after the first ixekizumab administration. Magnetic resonance imaging of the brain displayed a large T2-hyperintense infratentorial lesion involving the root of the fifth and seventh left cranial nerves. A thorough laboratoristic and instrumental work-up did not show elements suggestive of extracerebral neoplasms or infections. Therefore, neuronavigation-assisted brain biopsy was performed, and histologic analysis of the lesion revealed the presence of wide aggregates of foamy histiocytes diffusely infiltrating the brain parenchyma, in the absence of malignant tissue or histologic elements suggestive of central nervous system infections or primary histiocytoses. Steroid treatment (dexamethasone 8 mg/daily) was then administered with subsequent clinical amelioration. One month after hospital discharge, a brain magnetic resonance imaging showed a nearly complete resolution of the lesion. CONCLUSION: This is the first case of a cerebral inflammatory lesion occurring during treatment with ixekizumab. Although very rare, neurological complications may occur during anti-IL-17A therapies, thus leading to the need for careful monitoring of patients exposed to these drugs.

'Double target' ultrasound monitoring of biologic therapy in psoriatic arthritis.

OBJECTIVES: We aimed to 1) evaluate by power Doppler (PD) ultrasound (US) the response to therapy of the most inflamed joint and enthesis (target sites) in psoriatic arthritis (PsA) patients starting a biologic disease-modifying anti-rheumatic drug (bDMARD); and 2) to investigate the correlation between the US response and clinical data. METHODS: Consecutive PsA patients with US synovitis and US 'active' enthesitis, starting a bDMARD, were included. The joint with the highest OMERACT-EULAR-US composite score and the enthesis with the highest PD grade (targets) were identified at baseline. The US examination and clinical assessment were performed at 0, 3 and 6 months. The response of OMERACT-EULAR-US synovitis composite score was defined as reaching a grade = 0 at follow-up examination; synovial and entheseal PD responses were defined as a PD=0 and/or a reduction of ≥2 PD grades at follow-up examination. RESULTS: Thirty patients were included. Synovitis composite score, synovial PD and entheseal PD showed significant responses at 3 and 6 months compared to baseline (p<0.01). Synovial PD responses were higher than entheseal PD responses at 3 months (71.4% vs 40.0%, p=0.01) and 6 months (77.8% vs. 46.7%, p=0.02). US synovitis responses were correlated with DAPSA (p<0.01) and MDA responses (p=0.01 for composite score, p=0.02 for PD). CONCLUSIONS: US was found sensitive for monitoring treatment response in PsA patients starting a biologic drug. Entheseal PD was less responsive than synovial PD, suggesting that enthesitis may represent a 'difficult-to-treat' domain in PsA.

DKK-1 in psoriatic arthritis: Correlation with disease activity and enthesopathy.

BACKGROUND: Psoriatic arthritis (PsA) is a complex inflammatory disease with varied clinical characteristics. A pathognomonic characteristic of PsA is enthesitis. Entheseal inflammation ultimately leads to the production of new bone (enthesophytes). Dickkopf-related protein-1 (DKK-1) is a wingless (Wnt) inhibitor that inhibits osteoblast function. OBJECTIVES: Assessment of the serum level of DKK-1 and its association with disease activity and enthesopathy in PsA patients. METHODS: This observational case-control study included 50 PsA patients and 50 healthy volunteers matched for age and gender. All participants were subjected to full medical history, clinical assessment, PSA activity using Disease Activity Index for Psoriatic Arthritis (DAPSA) score, the severity and extent of psoriasis were determined by the Psoriasis Area and Severity Index (PASI). Ultrasonographic assessment of the entheses was done in accordance with the Madrid Sonographic Enthesitis Index (MASEI). Serum level of DKK-1 and correlation with disease activity and enthesopathy in PsA patients were assessed. RESULTS: There was no significant difference between patients and controls regarding age and sex. The mean value of SPARCC index, DAPSA score and PASI score were 6.74±4.58, 33.24±15.26, and 8.35±10.93, respectively. There was significant difference between patients and controls regarding the serum levels of DKK-1 and MASEI score (p<0.0001). There was a significant positive correlation between serum DKK-1 and MASEI (r: 0.43527, p: 0.00158), MASEI inflammatory (r: 0.37958, p: 0.00655), and MASEI damage (r: 0.38384, p: 0.00593). CONCLUSIONS: Serum DKK-1 levels were elevated in PsA patients and were found to be correlated with MASEI score for enthesopathy.