Early psoriatic arthritis

Prospective double-blind study on the value of musculoskeletal ultrasound by dermatologists as a screening instrument for psoriatic arthritis

OBJECTIVES

This study evaluated musculoskeletal ultrasound (MSUS) use by dermatologists previously trained on a novel handheld, chip-based ultrasound device (HHUD) to screen for early PsA.

METHODS

Twelve dermatologists were recruited to screen psoriasis patients for PsA using the novel HHUD in one major hospital in Bonn (Germany) and six private practices in surrounding regions. Patient screening was based on medical history, clinical examination, and the GEPARD questionnaire paired with an MSUS examination of up to three painful joints. All screened patients were then referred to rheumatologists, who determined the final diagnosis. The screening effect of MSUS was assessed according to its sensitivity and specificity before and after its application.

RESULTS

Between 1 October 2020 and 26 May 2021, a total of 140 psoriasis patients with arthralgia participated in this study. PsA was diagnosed in 19 (13.6%) cases. Before applying MSUS, dermatologists' screening sensitivity and specificity were recorded as 88.2% and 54.4%, respectively, while after applying MSUS the sensitivity and specificity changed to 70.6% and 90.4%, respectively. MSUS led to a change of PsA suspicion in 46 cases, with PsA no longer being suspected in 45 of them.

CONCLUSION

This study was able to demonstrate that PsA screening using MSUS by previously trained dermatologists can lead to more precise PsA detection and potentially decreased rheumatologist referral rates.

Assessment of four screening tools and retrieval of key questions to detect undiagnosed psoriatic arthritis in Chinese patients with psoriasis: A multicenter study

Several screening tools have been developed to facilitate early diagnosis of psoriatic arthritis (PsA); however, their performance varied greatly across different studies. In this study, we validated and compared the performance of four screening tools in detecting undiagnosed PsA Chinese patients with psoriasis, and determined the key questions and their weights. The four screening tools were the Early Arthritis for Psoriatic Patients (EARP) questionnaire, Psoriatic Arthritis Screening and Evaluation (PASE) questionnaire, Psoriasis and Arthritis Screening Questionnaire (PASQ), and Psoriasis Epidemiology Screening Tool (PEST). The receiver-operator curve (ROC) with area under curve (AUC) was used to determine sensitivity, specificity, and accuracy. Least absolute shrinkage and selection operator and logistic regression were utilized to retrieve key questions, and a nomogram was utilized to visualize their weights. Of 482 psoriasis patients from dermatology clinics, 77 were newly diagnosed with PsA. Another 68 patients with newly diagnosed PsA from rheumatology clinics were incorporated in the analysis. ROC analysis indicated that the optimal cut-off values for EARP, PASE, PASQ, and PEST were 3, 40, 7, and 3, with corresponding sensitivities of 91.4%, 88.6%, 86.2%, and 88.5%, and specificities of 88.6%, 75.2%, 80.2%, and 83.6%, respectively. The AUC of EARP (0.925) was higher than those of PASE (0.885), PASQ (0.905), and PEST (0.827). However, none of them were sufficiently sensitive to identify pure axial PsA (sensitivities of EARP, PASQ, and PASE were 25.0%, 36.8%, and 42.1%, respectively). Twelve key questions were retrieved from these four tools to establish a nomogram with a high discrimination (C-index = 0.993) and a good calibration (mean absolute error = 0.014). In conclusion, to screen undiagnosed PsA, EARP has slightly better balanced sensitivity and specificity, and higher accuracy. The retrieval of key questions and nomogram signify the necessity of attributing different scores to differently weighted questions when developing a new screening tool to make it function more efficiently.

A novel biomarker of MMP-cleaved prolargin is elevated in patients with psoriatic arthritis

Psoriatic arthritis (PsA) is a chronic musculoskeletal inflammatory disease found in up to 30% of psoriasis patients. Prolargin—an extracellular matrix (ECM) protein present in cartilage and tendon—has been previously shown elevated in serum of patients with psoriasis. ECM protein fragments can reflect tissue turnover and pathological changes; thus, this study aimed to develop, validate and characterize a novel biomarker PROM targeting a matrix metalloproteinase (MMP)-cleaved prolargin neo-epitope, and to evaluate it as a biomarker for PsA. A competitive ELISA was developed with a monoclonal mouse antibody; dilution- and spiking-recovery, inter- and intra-variation, and accuracy were evaluated. Serum levels were evaluated in 55 healthy individuals and 111 patients diagnosed with PsA by the CASPAR criteria. Results indicated that the PROM assay was specific for the neo-epitope. Inter- and intra- assay variations were 11% and 4%, respectively. PROM was elevated (p = 0.0003) in patients with PsA (median: 0.24, IQR: 0.19–0.31) compared to healthy controls (0.18; 0.14–0.23) at baseline. AUROC for separation of healthy controls from PsA patients was 0.674 (95% CI 0.597–0.744, P < 0.001). In conclusion, MMP-cleaved prolargin can be quantified in serum by the PROM assay and has the potential to separate patients with PsA from healthy controls.

Tumor necrosis factor inhibitors in psoriatic arthritis

INTRODUCTION

Psoriatic arthritis (PsA) is a chronic inflammatory disease that can result in significant disability. With the emergence of tumor necrosis factor inhibitors (TNFi), therapeutic outcomes in PsA have improved substantially. The clinical efficacy and the inhibition of radiographic progression demonstrated by TNFi have transformed the management of PsA. However, there is still an unmet need for a subset of patients who do not respond adequately to TNFi. Areas covered: This review provides an overview of the pharmacokinetics of TNFi, the efficacy of TNFi in PsA, and the role of immunogenicity of TNFi in the treatment of PsA. In addition, we address the use of TNFi in the setting of other medications utilized in the treatment of PsA and the potential future role of biosimilars. Expert commentary: Monoclonal antibodies exhibit complex and widely variable pharmacokinetics. The study of factors that can affect the pharmacokinetics, such as immunogenicity, is valuable to further define and understand the use of TNFi in PsA, especially in the subset of patients who do not respond adequately to these agents or lose effectiveness over time.

Comparative performance of psoriatic arthritis screening tools in patients with psoriasis in European/North American dermatology clinics

BACKGROUND

General practitioners/dermatologists may be aware of musculoskeletal symptoms in patients with psoriasis but may have difficulty accurately detecting psoriatic arthritis (PsA).

OBJECTIVE

We sought to evaluate 3 PsA screening questionnaires-the Psoriasis and Arthritis Screening Questionnaire (PASQ), Psoriasis Epidemiology Screening Tool (PEST), and Toronto Psoriatic Arthritis Screen (ToPAS)-based on rheumatologist assessment in patients with psoriasis.

METHODS

Consecutive unselected patients with psoriasis, initially evaluated by dermatologists for plaque psoriasis, were randomized to receive 1 of 3 questionnaires. Patients were subsequently evaluated by rheumatologists to establish/exclude clinical PsA diagnosis. Using clinical PsA diagnosis as the standard for comparison, questionnaire accuracy was assessed by calculating sensitivity/specificity and positive/negative predictive values.

RESULTS

Of 949 patients with psoriasis evaluated by rheumatologists, 285 (30%) received a clinical diagnosis of PsA (95% confidence interval 27%-33%). Probable PsA was detected in 45.1%, 43.0%, and 42.9% of patients using PASQ, PEST, and ToPAS, respectively. Sensitivity ranged from 0.67 to 0.84; specificity, 0.64 to 0.75; positive predictive value, 0.43 to 0.60; and negative predictive value, 0.83 to 0.91.

LIMITATIONS

Not all patients completed all questionnaires; lack of standardized diagnostic criteria introduced possible bias.

CONCLUSION

PASQ, PEST, and ToPAS are useful screening tools that can help dermatologists identify patients without PsA and patients with possible PsA who may benefit from rheumatologist assessment.

[Screening and early diagnosis of psoriasis arthritis]

Psoriasis arthritis (PsA) encompasses many diverse clinical symptoms. Epidemiological data about the prevalence in general, predisposed age groups, prevalence of joint, spine, enthesis, and extra-articular manifestations are very heterogeneous. Even for the PsA specialist the clinical picture is not always easy to differentiate from other overlapping or clinically similar disease entities. This paper tries to give some guidance on how to screen for and how to detect PsA early in the population of psoriasis patients on the basis of the Mainz PsA screening and early diagnosis algorithm.

Limitations in Screening Instruments for Psoriatic Arthritis: A Comparison of Instruments in Patients with Psoriasis

Objective.

To compare the abilities of 3 validated screening instruments to predict the diagnosis of psoriatic arthritis (PsA) in patients with psoriasis.

Methods.

Prior to a rheumatologic evaluation, 213 participants in the Utah Psoriasis Initiative completed the Psoriasis Epidemiology Screening project (PEST), the Toronto Psoriatic Arthritis Screen (ToPAS), and the Psoriatic Arthritis Screening and Evaluation (PASE). Previously established instrument cutoff scores were used to designate positive and negative classifications. Sensitivities and specificities were determined by comparing instrument classifications to the rheumatologist’s diagnosis. Phenotypic features and alternative diagnoses were compared between participants who screened positively and negatively on each instrument. Discrepancies between the rheumatologist’s examination findings and responses to specific instrument questions were compared.

Results.

The sensitivities of PEST, ToPAS, and PASE were 85%, 75%, and 68%, and the specificities were 45%, 55%, and 50%, respectively. The instruments were less sensitive in patients with lower disease activity, fewer PsA features, and shorter disease duration. The instruments did not consistently differentiate between PsA and other types of musculoskeletal disease. Discrepancies between examination findings and responses to instrument questions occurred more frequently with ToPAS than with PEST and PASE.

Conclusion.

Sensitivities and specificities for PEST, ToPAS, and PASE were lower than previously reported. This population included patients with PsA and other types of musculoskeletal disease and may represent those most likely to complete a screening instrument and follow through with a rheumatology referral. Further analyses may enable the development of more successful screening strategies for PsA in psoriasis patients with musculoskeletal complaints.

Psoriatic arthritis: recent progress in pathophysiology and drug development

Psoriatic arthritis (PsA) is the second most common inflammatory arthropathy, after rheumatoid arthritis diagnosis, in early arthritis clinics. Most patients have established psoriasis, often for years, prior to the onset of joint pain and swelling; in addition, associated features of nail disease, dactylitis, enthesitis, spondylitis or uveitis may be present. Psoriasis may not be immediately apparent, as small or patchy lesions may occur in the scalp or perineum. PsA presents as a symmetrical polyarthritis, similar to rheumatoid arthritis, or an asymmetrical oligoarthritis with a predilection for the distal interphalangeal joints. Spinal involvement is similar, although not identical, to ankylosing spondylitis. Joint damage occurs early; up to 50% of PsA patients have an 11% annual erosion rate in the first 2 years of disease duration, suggesting it is not a benign condition. There have been significant advances in our understanding of PsA pathogenesis in recent years, in the areas of genetics and molecular biology, implicating both the innate and the adaptive immune systems. This has lead to the introduction of evidence-based targeted therapy, primarily with tumour necrosis factor inhibitor (TNFi) agents. Therapy with disease-modifying anti-rheumatic drugs, such as methotrexate and leflunomide, remains the first-choice therapeutic intervention, even though there are few randomised controlled trials with these agents. In contrast, a number of successful studies of TNFi agents demonstrate excellent efficacy, in combination with methotrexate, and several novel agents are currently in development for the treatment of PsA.

Ultrasound revealing subclinical enthesopathy at the greater trochanter level in patients with spondyloarthritis

This study was conducted to determine the prevalence of subclinical entheseal involvement at the greater trochanter level by ultrasound in patients with spondyloarthritis. Forty-six patients with spondyloarthritis and 46 healthy age- and sex-matched controls were studied. All patients with no clinical evidence of enthesopathy at the greater trochanter underwent an ultrasound examination. The following three entheses were scanned bilaterally: anterior insertion of gluteus minimus, anterior insertion of gluteus medius, and posterior insertion of gluteus medius. Ultrasound findings of enthesopathy were thickening, calcifications, bone erosions, enthesophytes, bursitis, and power Doppler signal. A total of 276 entheses were evaluated in spondyloarthritis patients. In 112 out of 276 (40.5%), grayscale ultrasound found enthesopathy. The enthesis with the highest number of signs of enthesopathy was the anterior insertion of gluteus medius (46/276) (16%), followed by posterior insertion of gluteus medius (37/276) (13.4%) and anterior insertion of gluteus minimus (29/276) (10.5%). In the healthy population, ultrasound found entesopathy in 80 out of 276 (29%) entheseal sites (p < 0.0001). Posterior insertion of gluteus medius enthesis was the more frequently involved (34/276) (12.3%), followed by anterior insertion of gluteus medius (24/276) (8.6%) and anterior insertion of gluteus minimus (22/276) (7.9%). Power Doppler was found more frequently in patients with spondyloarthritis compared with healthy controls (1% vs 0%). Our results show a higher prevalence of subclinical enthesopathy at the greater trochanter level in patients with spondyloarthritis than in age- and sex-matched healthy controls.

Subclinical entheseal involvement in patients with psoriasis: an ultrasound study

OBJECTIVES

The main aim of the present study was to determine the prevalence of subclinical entheseal involvement at lower limbs by ultrasound (US) in patients with psoriasis. The secondary aim was to determine the interobserver reliability of the Glasgow Ultrasound Enthesitis Scoring System (GUESS) and power Doppler (PD) technique in the assessment of enthesopathy.

METHODS

The study was conducted on 45 patients with psoriasis and 45 healthy sex- and age-matched controls. All patients with no clinical evidence of arthritis or enthesitis underwent an US examination. All US findings were identified according to GUESS. The interobserver reliability was calculated in 15 patients with psoriasis.

RESULTS

A total of 450 entheses in 45 patients with psoriasis were evaluated by US. In 148 of 450 (32.9%) entheses, grayscale US found signs indicative of enthesopathy. In 4/450 (0.9%) entheses PD signal was detected. In the healthy population, US found signs of enthesopathy in 38 of 450 (8.4%) entheses and no PD signal was detected. The GUESS score was significantly higher in patients with psoriasis than in healthy controls (P < 0.0001). Both concordance correlation coefficient and unweighted κ values for US findings showed an excellent agreement (0.906 and 0.890, respectively).

CONCLUSIONS

Our results indicate that both grayscale US and PD findings indicative of enthesopathy were more frequent in patients with psoriasis. The US ability to detect signs of subclinical enthesopathy should be the object of longitudinal investigations to define its value in predicting the clinical onset of psoriatic arthritis.

[Detection of psoriasis arthritis with the GEPARD patient questionnaire in a dermatologic outpatient setting]

BACKGROUND

Diagnosis of psoriasis arthritis (PsA) is often delayed in an outpatient dermatological setting. Therefore, we compiled a patient questionnaire (GEPARD, GErman Psoriasis ARthritis Diagnostic questionnaire) to detect PsA in psoriasis outpatients.

PATIENTS AND METHODS

Initially, between 2005 and 2007, we evaluated GEPARD in the outpatient setting of our Department of Dermatology with the Vasey and Espinoza criteria. In May 2008, the questionnaire was distributed to practices in the Regensburg area, Germany. Patients who filled out the GEPARD questionnaire were invited for a rheumatological work-up and, where indicated, arthrosonography, conventional X-ray, MRI, and scintigraphy examinations were performed. PsA was classified on the basis of the CASPAR criteria.

RESULTS

We calculated a sum cut-off score of >or= 4 positive answers in the first cohort. Of all 54 patients examined 63% could be diagnosed with PsA according to the CASPAR criteria. After a complete work-up with all diagnostic means 79.6% (43 patients) could be detected with inflammatory joint manifestations.

CONCLUSION

It is possible to detect PsA patients in a dermatologic outpatient setting with the GEPARD questionnaire.

Remission in psoriatic arthritis: is it possible and how can it be predicted?

INTRODUCTION

Since remission is now possible in psoriatic arthritis (PsA) we wished to examine remission rates in PsA patients following anti tumour necrosis factor alpha (TNFalpha) therapy and to examine possible predictors of response.

METHODS

Analysis of a prospective patient cohort attending a biologic clinic, between November 2004 and March 2008, was performed prior to commencing therapy and at regular intervals. Baseline clinical characteristics including demographics, previous disease-modifying antirheumatic drug (DMARD) response, tender and swollen joint counts, early morning stiffness, pain visual analogue score, patient global assessment, C reactive protein (CRP) and health assessment questionnaire (HAQ) were collected.

RESULTS

A total of 473 patients (152 PsA; 321 rheumatoid arthritis (RA)) were analyzed. At 12 months remission, defined according to the disease activity score using 28 joint count and CRP (DAS28-CRP), was achieved in 58% of PsA patients compared to 44% of RA patients, significant improvement in outcome measures were noted in both groups (P<0.05). Analysis of a subgroup of PsA and RA patients matched for DAS28-CRP at baseline also showed higher numbers of PsA patients achieving remission. Linear regression analysis identified the HAQ at baseline as the best predictor of remission in PsA patients (P<0.001).

CONCLUSIONS

DAS28 remission is possible in PsA patients at one year following anti-TNF therapy, at higher rates than in RA patients and is predicted by baseline HAQ.

Value of entheseal ultrasonography and serum cartilage oligomeric matrix protein in the preclinical diagnosis of psoriatic arthritis

Objective:

To evaluate the utility of entheseal ultrasonography and serum COMP in the preclinical diagnosis of psoriatic arthritis.

Methods:

60 psoriatic patients were divided into: 30 patients with psoriasis (group I) and 30 patients with psoriatic arthritis as control (group II). They underwent independent clinical and ultrasonographic examination of both lower limbs at the calcaneal insertions of Achilles tendons. Psoriatic arthritis disease activity and severity was assessed by modified DAS28 and Steinbrockers scores. Serum levels of COMP were measured for all patients by ELISA.

Results:

On clinical examination, no entheseal abnormalities were detected in group I while they were present in 23.3% of group II with statistically significant difference between them (P < 0.001). Ultrasonographic entheseal abnormalities were detected in 33.3% of group I and in 46.7% of group II with no significant difference between them (P > 0.05). Serum COMP were significantly elevated in group I and II with no statistically significant difference between them (mean ± SD 5.9 ± 3 and 6.8 ± 12 respectively, P > 0.05). Entheseal ultrasound was more specific (67%) while serum COMP was more sensitive (87%) in the preclinical diagnosis of psoriatic arthritis. Serum COMP levels were significantly correlated with CRP in both groups and with DAS28 and Steinbrockers scores in group II (P < 0.01).

Conclusion:

Entheseal ultrasonography and serum COMP levels may be used complementary to each other for preclinical diagnosis of psoriatic arthritis. Serum COMP seems to be promising prognostic marker for psoriatic arthritis patients.

CD16 (FcRgammaIII) as a potential marker of osteoclast precursors in psoriatic arthritis

Introduction

Psoriatic arthritis (PsA) is a chronic inflammatory arthritis characterized by bone erosion mediated by osteoclasts (OC). Our previous studies showed an elevated frequency of OC precursors (OCP) in PsA patients. Here, we examined if OC arise from CD16-positive monocytes in PsA.

Methods

Peripheral blood mononuclear cells (PBMC) or monocytes were isolated from human peripheral blood and sorted based on CD16 expression. Sorted cells were cultured alone or with bone wafers in the presence of receptor activator of nuclear factor kappa-B ligand (RANKL) and macrophage colony-stimulating factor (M-CSF). Enumeration and bone erosion activity of OC were examined after culture. The effects of tumor necrosis factor-alpha (TNFα), OC-promoting (M-CSF plus RANKL), and dendritic cell (DC)-promoting (GM-CSF plus interleukin (IL)-4) cytokines on CD16 surface expression were examined by flow cytometry.

Results

PsA and psoriasis (Ps) subjects had a higher percentage of circulating inflammatory CD14+CD16+ cells than healthy controls (HC). Exposure of cells to OC-promoting, but not DC-promoting media, was associated with CD16 up-regulation. PBMC of Ps and PsA had a higher frequency of cells expressing intermediate levels of CD16. OC were mainly derived from CD16+ cells in PsA. Increased CD16 expression was associated with a higher bone erosion activity in PsA.

Conclusions

An increased frequency of circulating CD14+CD16+ cells was noted in PsA compared to controls, and intermediate levels of CD16 may suggest a transitional state of OCP during osteoclastogenesis. Intriguingly, TNFα blocked CD16 expression on a subset of CD14+ monocytes. Collectively, our data suggest that CD16 has the potential to serve as an OCP marker in inflammatory arthritis.

Treatment strategies for early psoriatic arthritis

BACKGROUND

Until a few years ago, the early diagnosis of psoriatic arthritis (PsA) did not receive much attention, especially in view of the lack of drugs capable of altering the disease course. This changed with the introduction of the TNF-alpha-blocking agents, as a result of which the early diagnosis of PsA is now a topic of great interest.

OBJECTIVE

The aim of the study was to review the treatment for PsA in order to determine the optimal approach to managing early disease.

METHODS

The systematic review performed by members of GRAPPA (Group of Research and Assessment of Psoriasis and Psoriatic Arthritis) was integrated with data from more recent studies.

RESULTS/CONCLUSION

After making the diagnosis of PsA, the next step is to stage of the disease with the aim of establishing the prevalent manifestation (peripheral arthritis, peripheral enthesitis, axial involvement and dactylitis) and degree of severity (mild, moderate or severe) of the disease. Each patient should be treated according to the defined disease status following the suggested treatment algorithms.

Spondyloarthritis: clinical suspicion, diagnosis, and sports

Spondyloarthritis (SpA), a family of inflammatory back diseases including ankylosing spondylitis, is an important and under-recognized cause of chronic back pain in younger patients who are likely to participate in sports and athletic activities. These diseases are characterized by the presence of inflammatory back pain--lumbar or buttock/hip pain lasting longer than 3 months associated with improvement with activity, worsening with rest, relief with non-steroidal anti-inflammatory drugs (NSAIDs), and morning stiffness lasting longer than 30 min. There are also characteristic radiographic findings involving the sacroiliac joints, vertebrae, and in certain diseases, the peripheral joints. Exercise has long been recognized as a key component of the therapy of SpA, yielding benefits in mobility, pain, stiffness, functionality, and depression. Sports also pose a risk to patients with SpA as these patients are at high risk of spinal fracture and spinal cord injury.