Deconstruction of rheumatoid arthritis synovium defines inflammatory subtypes.

Rheumatoid arthritis is a prototypical autoimmune disease that causes joint inflammation and destruction1. There is currently no cure for rheumatoid arthritis, and the effectiveness of treatments varies across patients, suggesting an undefined pathogenic diversity1,2. Here, to deconstruct the cell states and pathways that characterize this pathogenic heterogeneity, we profiled the full spectrum of cells in inflamed synovium from patients with rheumatoid arthritis. We used multi-modal single-cell RNA-sequencing and surface protein data coupled with histology of synovial tissue from 79 donors to build single-cell atlas of rheumatoid arthritis synovial tissue that includes more than 314,000 cells. We stratified tissues into six groups, referred to as cell-type abundance phenotypes (CTAPs), each characterized by selectively enriched cell states. These CTAPs demonstrate the diversity of synovial inflammation in rheumatoid arthritis, ranging from samples enriched for T and B cells to those largely lacking lymphocytes. Disease-relevant cell states, cytokines, risk genes, histology and serology metrics are associated with particular CTAPs. CTAPs are dynamic and can predict treatment response, highlighting the clinical utility of classifying rheumatoid arthritis synovial phenotypes. This comprehensive atlas and molecular, tissue-based stratification of rheumatoid arthritis synovial tissue reveal new insights into rheumatoid arthritis pathology and heterogeneity that could inform novel targeted treatments.

Precision Medicine in Rheumatology: The Promise of Ultrasound-Guided Synovial Biopsy, Barriers to Its Implementation in the United States, and Proposed Solutions.

PURPOSE OF REVIEW: In the clinical evaluation of inflammatory arthritis and the research into its pathogenesis, there is a growing role for the direct analysis of synovial tissue. Over the years, various biopsy techniques have been used to obtain human synovial tissue samples, and there have been progressive improvements in the safety, tolerability, and utility of the procedure. RECENT FINDINGS: The latest advancement in synovial tissue biopsy techniques is the use of ultrasound imaging to guide the biopsy device, along with evolution in the characteristics of the device itself. While ultrasound guided synovial biopsy (UGSB) has taken a strong foothold in Europe, the procedure is still relatively new to the United States of America (USA). In this paper, we describe the expansion of UGSB in the USA, elucidate the challenges faced by rheumatologists developing UGSB programs in the USA, and describe several strategies for overcoming these challenges.

Power doppler ultrasound signal predicts abnormal HDL function in patients with rheumatoid arthritis.

Active rheumatoid arthritis (RA) is associated with increased cardiovascular risk and impaired function of high-density lipoprotein (HDL). Previous work suggests that HDL may become dysfunctional through oxidative modifications within the RA joint. The current work evaluates an association of synovial power doppler ultrasound signal (PDUS) with HDL function and structure. Two open-label clinical therapeutic studies using PDUS as a disease outcome measure were included in this analysis, including a 12-month trial of subcutaneous abatacept in 24 RA patients and a 6-month trial of IV tocilizumab in 46 RA patients. Laboratory assays included assessments of HDL function and structure, HDL and total cholesterol levels, and a cytokine/chemokine panel. Patients with the highest baseline PDUS scores in both clinical studies, had worse HDL function, including suppression of paraoxonase 1 (PON1) activity as well as lower HDL-C levels. Associations between other disease assessments (DAS28 and CDAI) and HDL function/structure were noted but were generally of lesser magnitude and consistency than PDUS across the HDL profile. Treatment with tocilizumab for 6 months was associated with increases in cholesterol levels and improvements in the HDL function profile, which correlated with greater decreases in PDUS scores. Similar trends were noted following treatment with abatacept for 3 months. Higher baseline PDUS scores identified patients with worse HDL function. This data supports previous work suggesting a direct association of joint inflammation with abnormal HDL function.

Joint-specific assessment of swelling and power Doppler in obese rheumatoid arthritis patients.

BACKGROUND: Clinical swollen joint examination of the obese rheumatoid arthritis (RA) patient can be difficult. Musculoskeletal Ultrasound (MSUS) has higher sensitivity than physical examination for swollen joints (SJ). The purpose of this study was to determine the joint-specific association between power Doppler (PDUS) and clinical SJ in RA across body mass index (BMI) categories. METHODS: Cross-sectional clinical and laboratory data were collected on 43 RA patients. PDUS was performed on 9 joints (wrist, metacarpalphalangeal 2-5, proximal interphalgeal 2/3 and metatarsalphalangeal 2/5). DAS28 and clinical disease activity index (CDAI) were calculated. Patients were categorized by BMI: <25, 25-30, and >30. Demographic and clinical characteristics were compared across BMI groups with Kruskal-Wallis test and chi-square tests. Joint-level associations between PDUS and clinically SJ were evaluated with mixed effects logistic regression models. RESULTS: While demographics and clinically-determined disease activity were similar among BMI groups, PDUS scores significantly differed (p = 0.02). Using PDUS activity as the reference standard for synovitis and clinically SJ as the test, the positive predictive value of SJ was significantly lower in higher BMI groups (0.71 in BMI < 25, 0.58 in BMI 25-30 and 0.44 in BMI < 30) (p = 0.02). The logistic model demonstrated that increased BMI category resulted in decreased likelihood of PDUS positivity (OR 0.52, p = 0.03). CONCLUSIONS: This study suggests that in an obese RA patient, a clinically assessed SJ is less likely to represent true synovitis (as measured by PDUS). Disease activity in obese RA patients may be overestimated by CDAI/DAS28 calculations and clinicians when considering change in therapy.

[THE PREVALENCE OF POSITIVE POWER DOPPLER SIGNALS BY MUSCULOSKELETAL ULTRASOUND OF HANDS IN SCLERODERMA PATIENTS].

BACKGROUND: Musculoskeletal ultrasound is increasingly used in the evaluation of joint inflammation. Power Doppler can identify increased hyperemia which indicates inflammation. OBJECTIVES: To measure the prevalence and level of positive Power Doppler signals at the hand joints of scleroderma patients. METHODS: Ten scleroderma patients were examined by ultrasound of the dominant hand. Power Doppler signals were measured at the wrist as well as the metacarpophalangeal joints (MCPS), proximal interphalangeal joints (PIPS) and distal interphalangeal joints (DIPS) at the second to fifth fingers. Clinical information regarding age, gender, disease duration, level of involvement (limited or diffuse) and skin score were collected. The data were taken from a larger ultrasound study from UCLA University that examined the validation of ultrasound in scleroderma. RESULTS: Mean age was 51.7 years and 70% were females; 212 joints were examined. Positive Power Doppler signals were found in 30% of patients and were mostly low grade. Power Doppler signals were found in 3.3% of the joints of scleroderma patients. DISCUSSION: Level of Power Doppler signals which probably reflects the level of joint inflammation was low in the scleroderma patients and its prevalence was low.

An OMERACT reliability exercise of inflammatory and structural abnormalities in patients with knee osteoarthritis using ultrasound assessment.

OBJECTIVE: To assess whether ultrasonography (US) is reliable for the evaluation of inflammatory and structural abnormalities in patients with knee osteoarthritis (OA). METHODS: Thirteen patients with early knee OA were examined by 11 experienced sonographers during 2 days. Dichotomous and semiquantitative scoring was performed on synovitis characteristics in various aspects of the knee joint. Semiquantitative scoring was done of osteophytes at the medial and lateral femorotibial joint space or cartilage damage of the trochlea and on medial meniscal damage bilaterally. Intra- and interobserver reliability were computed by use of unweighted and weighted κ coefficients. RESULTS: Intra- and interobserver reliability scores were moderate to good for synovitis (mean κ 0.67 and 0.52, respectively) as well as moderate to good for the global synovitis (0.70 and 0.50, respectively). Mean intra- and interobserver reliability κ for cartilage damage, medial meniscal damage and osteophytes ranged from fair to good (0.55 and 0.34, 0.75 and 0.56, 0.73 and 0.60, respectively). CONCLUSIONS: Using a standardised protocol, dichotomous and semiquantitative US scoring of pathological changes in knee OA can be reliable.

Adalimumab as steroid-sparing treatment of inflammatory-stage thyroid eye disease.

PURPOSE: Steroids are often used as medical therapy for active thyroid eye disease (TED). While high-dose steroids have been shown to be effective in reducing the severity of TED symptoms, the side effects of steroids can be severe. As the pathogenesis of TED is thought to involve the upregulation of proinflammatory cytokines, including tumor necrosis factor-α (TNF-α), it has been postulated that anti-TNF agents may be used as steroid-sparing agents in the treatment of TED. This retrospective study was conducted to examine the efficacy of adalimumab, a subcutaneously administered TNF-α antagonist, in treating the inflammatory symptoms of active TED. METHODS: All patients in the inflammatory phase of TED who were treated with adalimumab at the Jules Stein Eye Institute over a 2-year period were reviewed. Data concerning visual acuity, optic nerve function, extraocular motility restriction, binocular visual fields, and proptosis were extracted from patient charts. Clinical photographs from baseline and 3-month follow-up visits were reviewed by masked orbital specialists. Each photograph was graded on the severity of conjunctival injection, chemosis, eyelid erythema, and eyelid edema on a scale from 1 to 4. An inflammatory score was calculated as the sum of these 4 elements. Groups were compared using paired t tests. RESULTS: Six of 10 patients showed a decrease in inflammatory score while on adalimumab, whereas 3 showed an increase and 1 stayed the same. One patient experienced a significant complication (hospital admission for sepsis). Eight patients received concomitant tapering steroids during the first 6 weeks of therapy as the adalimumab reached maximum efficacy. When data from all 10 subjects were analyzed together, there was no significant change in inflammatory index after 3 months of treatment with adalimumab. However, when the 5 patients with a high baseline inflammatory index (>4) were considered separately, there was a significant improvement (mean decrease of 5.2±2.7; p<0.01) after adalimumab treatment. Four of 5 patients also reported a subjective improvement in symptoms while on adalimumab. CONCLUSIONS: This study suggests that adalimumab may have a role in the treatment of active TED with prominent inflammatory symptoms. The use of adalimumab and other immunosuppressive agents in the treatment of TED may help to mitigate some of the metabolic and psychiatric side effects of pulsed steroid treatment. A future randomized controlled study will be necessary to determine the efficacy of adalimumab as a primary therapy for TED.

The Importance of Ultrasound-Guided Synovial Biopsy in the Workup of Seronegative Inflammatory Arthritis: A Case Report.

We report a case of a 74-year-old male who presented with typical clinical features of rheumatoid arthritis (RA), as well as elevated markers of inflammation. However, the patient did not respond to multiple RA treatments, and an ultrasound-guided synovial biopsy (UGSB) of the right wrist was performed, which established the diagnosis of amyloidosis. A variety of inflammatory conditions sometimes get misdiagnosed as seronegative RA due to similarities in clinical presentation. This case report highlights the importance of a thorough workup in patients who appear to have seronegative RA. Given the wide availability of ultrasound-guided, minimally invasive synovial biopsies, these procedures should be employed more often to detect rare conditions that may mimic seronegative RA, such as amyloidosis.

Perturbation of nuclear lamin A causes cell death in chondrocytes.

OBJECTIVE: Mutations in LMNA encoding the A-type lamins cause several diseases, including those with features of premature aging and skeletal abnormalities. The aim of this study was to examine the expression of lamin A in cartilage from patients with osteoarthritis (OA) and the effects of its overexpression on chondrocyte senescence and apoptosis. METHODS: Human chondrocyte-like cells (SW-1353) were used. RNA isolated from human OA and non-OA cartilage was used for profiling messenger RNA expression, using Affymetrix microarray analysis. The effects of lamin A overexpression on mitochondrial function and apoptosis were examined by assessing mitochondrial membrane potential, ATP levels, and cytochrome c release, and with a TUNEL assay. Western blotting was performed to determine protein expression. RESULTS: Lamin A expression was markedly elevated in OA cartilage samples compared with non-OA control samples. Western blot analysis confirmed increased expression of lamin A in OA compared with non-OA cartilage. Interleukin-1ß treatment inhibited lamin A accumulation, whereas treatment with prostaglandin E(2) (PGE(2) ) caused a marked increase in lamin A accumulation. These effects of exogenous PGE(2) on lamin A expression were mediated via the EP(2) /EP(4) receptors. Transfected chondrocytes that expressed lamin A displayed markers of early senescence/apoptosis. CONCLUSION: The results of this study suggest that lamin A is up-regulated in OA chondrocytes, and that increased nuclear accumulation of lamin A in response to catabolic stress may account for the premature aging phenotype and apoptosis of OA chondrocytes.

Best practices for ultrasound-guided synovial biopsy in the United States.

The target organ in many forms of inflammatory arthritis is the synovium. However, synovial tissue has historically been perceived as either difficult to obtain or of little practical value. Ultrasound-guided synovial biopsy [UGSB] is a safe and well-tolerated bedside procedure that is established in Europe and rapidly growing in popularity in the United States. The technique can be mastered by rheumatologists who are already experienced in ultrasound-guided procedures such as joint aspirations. The USGB procedure allows the proceduralist to access small, medium, and large joints and is inexpensive and less invasive compared to surgical alternatives. The relative ease of obtaining this tissue, along with recent research suggesting that synovium may have more clinical and investigational utility than previously thought, has led clinicians and researchers to a new appreciation of the role of synovial biopsy in both the clinical and research setting. In this manuscript, the authors present recommendations on best practices for ultrasound-guided synovial biopsy in the United States, based on our initial training with well-established experts overseas and our own subsequent collective experience in performing numerous synovial biopsies in the United States over the past 7 years for both clinical and research indications. We envision a future where UGSB is more frequently incorporated in the standard diagnostic workup of arthritis and drives novel research initiatives.

Using the antinuclear antibody test to diagnose rheumatic diseases: when does a positive test warrant further investigation?

The anti-nuclear antibody (ANA) test is ordered commonly as a screening test for rheumatic diseases. Although ANA positivity is highly sensitive for certain rheumatic diseases, the presence of ANA is nonspecific and can be associated with numerous nonrheumatic factors, including environmental exposures, malignancies, drugs, and infections. This article describes a practical approach for physicians when evaluating patients using a positive ANA test. In the absence of connective tissue disease symptoms, the ANA test has minimal clinical significance in diagnosing rheumatic diseases. Understanding how to use ANA test results appropriately may reduce unnecessary referrals and costly workups.

A comparison of arthrocentesis teaching tools: cadavers, synthetic joint models, and the relative utility of different educational modalities in improving trainees' comfort with procedures.

BACKGROUND: Each year, rheumatology programs across the country teach incoming trainees the skill of arthrocentesis, but the relative effectiveness of various teaching techniques has not been assessed in a systematic way. OBJECTIVES: We compared approaches to teaching arthrocentesis using cadavers versus anatomic models. METHODS: In a pilot study, new rheumatology fellows (n = 7) from 2 academic institutions were surveyed at 3 points during arthrocentesis training: (1) before assuming patient care; (2) after lecture with handouts, followed by practice either on cadavers (group A) or on synthetic joint models (group B); and (3) 6 weeks into fellowship. Fellows rated their comfort levels for arthrocentesis of specific joints using 9-point Likert scales. Fellows also retrospectively rated the utility of individual teaching modalities in helping them to learn. As a follow-up study, internal medicine residents taking part in a month-long rheumatology rotation were similarly surveyed on their comfort level performing knee and shoulder arthrocentesis before a cadaver teaching laboratory and at the end of their month rotation. RESULTS: The initial mean comfort level performing arthrocentesis for all fellows was low (2.01). After the cadaver teaching session, group A fellows experienced an overall comfort level increase of 1.95, with the largest single increase reported for shoulder arthrocentesis (3.86). After the anatomic model teaching session, group B fellows reported a mean comfort increase of 1.29, with the largest increase reported for knee arthrocentesis (3.13). The subsequent study with residents confirmed significant increases in comfort after the cadaver laboratory. When surveyed, the learning experience fellows considered most effective was the opportunity to perform procedures under supervision and guidance, followed by training on cadavers. CONCLUSIONS: Although all teaching interventions for trainees learning arthrocentesis were helpful for increasing trainee's comfort with arthrocentesis, the use of cadavers seemed to be superior to synthetic anatomic models or lectures alone. The specific impact of these teaching interventions on actual competence, defined as a performance outcome, deserves additional study.

Optimizing Reliability of Real-Time Sonographic Examination and Scoring of Joint Synovitis in Rheumatoid Arthritis.

OBJECTIVE: Musculoskeletal ultrasound real-time image acquisition and scoring are complex, and many factors affect reliability. Static image reliability does not guarantee real-time scoring. This study aimed to identify factors and solutions to improve real-time scoring reliability for the grey scale and power Doppler evaluation of synovitis. We also report on using a novel musculoskeletal ultrasound synovitis rule-based scoring atlas. METHODS: In four stages, we evaluated inter- and intra-reader reliability among three ultrasonographers (US1-3). Intra- and inter-reader reliability was calculated using weighted-kappa, intraclass correlation coefficient, and Spearman correlation. Reliability statistics were compared between stages using permutation tests to compute empirical distributions for differences in those statistics. At each stage, factors that diminished reliability were identified and addressed. After intensive reliability exercises, a RA MSUS atlas with in-depth scoring rules was generated to improve interpretive reliability. RESULTS: The three ultrasonographers had good to excellent intra-reader reliability for real-time acquisition scoring over 2432 views (weighted kappa 0.52-0.80, intraclass correlation coefficient 0.59-0.86, and Spearman correlation 0.64-0.86). Inter-reader reliability was good to excellent between US1/US2 and US1/US3 (weighted kappa 0.51-0.66, intraclass correlation coefficient 0.66-0.75, Spearman correlation 0.59-0.73). US1 achieved significant improvement in intra-reader reliability from stage 1 to stage 2 (p<0.05, weighted-kappa 0.63 to 0.80, intraclass correlation coefficient 0.71 to 0.86, Spearman 0.67 to 0.86) with use of the atlas.  Conclusion: This rheumatoid arthritis musculoskeletal ultrasound study addressed complex factors affecting musculoskeletal ultrasound acquisition-scoring reliability. Systematic identification and amelioration of many factors and using a novel rule-based scoring atlas significantly improved intra-reader reliability.

Sentinel joint scoring in rheumatoid arthritis: an individualized power Doppler assessment strategy.

OBJECTIVE: Musculoskeletal ultrasound quantifies the total synovial inflammatory burden in rheumatoid arthritis (RA) but is time consuming when scanning numerous joints. This study evaluated a novel patient-centered method for constructing a longitudinal ultrasound score in RA patients. METHODS: Fifty-four RA patients starting intravenous tocilizumab were evaluated with power Doppler ultrasound (PDUS) of 34 joints and DAS28-ESR was assessed at baseline and weeks 4, 12, 16, and 24. The sentinel joint score (SJS) was derived from the reduced subset of joints with PDUS ≥ 1 at baseline. Total PDUS (tPDUS) score and US7 were also calculated. Changes in tPDUS and SJS were correlated. Effect sizes were calculated for tPDUS, SJS, and US7. The proportion of "flipped" joints without baseline PDUS signal that later developed PDUS signal was estimated. RESULTS: At baseline, 1236/1829 joints scanned (67.5%) did not have PDUS signal. The proportion of "flipped" joints at 24 weeks was 5.6% for ≥ 1, 2.9% for ≥ 2, and 1.0% for = 3 PD. tPDUS and SJS scores were highly correlated (r = 0.91 to 0.97). Overall the effect sizes for tPDUS, SJS, and US7 increased over 24 weeks, where SJS was the highest (SJS 1.00 4-week, 1.07 12-week, 1.26 24-week) and tPDUS and US7 were comparable (tPDUS 0.32 4-week, 0.52 12-week, 0.84 24-week; US7 0.23 4-week, 0.52 12-week, 0.74 24-week). CONCLUSION: In RA patients starting a biologic, scanning only joints with baseline PDUS signal can substantially reduce the number of joints requiring follow-up scanning by 67.5% and improves feasibility. "Flipped" joints are infrequently seen after starting therapy. TRIAL REGISTRATION: ClinicalTrials.gov NCT01717859 Key messages • Only a small percent of joints develop power Doppler signal after baseline scanning. • Changes in the SJS correlate well with changes in clinical activity measured by DAS28-ESR over time. • The SJS effect size is higher than total PDUS and US7 scores, and may improve examination feasibility.

Doppler ultrasound impacts response to intravenous tocilizumab in rheumatoid arthritis patients.

OBJECTIVE: Within rheumatoid arthritis (RA) patients treated with intravenous tocilizumab (IV-TCZ), it is unclear if power Doppler ultrasonography (PDUS) can predict future clinical response. This study sought to determine if baseline PDUS or its early changes can predict 12-week and 24-week disease activity outcomes, and quantify the need for dose escalation (4 to 8 mg/kg). METHODS: Fifty-four RA patients starting IV-TCZ were evaluated at baseline, 4, 6, 12, 16, and 24 weeks using 34-joint PDUS (US34-PDUS), clinical disease activity index (CDAI), 28-joint disease activity score using erythrocyte sedimentation rate (DAS28-ESR), ACR 20/50/70, health assessment questionnaire-disability index (HAQ-DI), and PDUS 20/50/70, a novel measure. Logistic regression models evaluated the predictive utility of US34-PDUS of DAS28-ESR response after adjusting for covariates. RESULTS: Ninety-four percent of patients required dose escalation to 8 mg/kg. US34-PDUS, CDAI, and DAS28-ESR improved significantly over 24 weeks (p < 0.001). Baseline PDUS and 12-week PDUS change correlated with CDAI at 24 weeks (p < 0.05). Logistic regression demonstrated baseline US34-PDUS was independently associated with DAS28-ESR ≥ 1.2 response, even after adjusting for baseline DAS28-ESR (p = 0.03). CDAI, DAS28-ESR, and their components increased across PDUS 20/50/70 categories; however, HAQ-DI did not. CONCLUSION: RA patients treated with IV-TCZ for 24 weeks demonstrated significant improvement, and baseline/early changes in PDUS were predictive of later clinical response. The PDUS 20/50/70 measure is a novel metric of response. This study suggests that IV-TCZ 4 mg/kg may not be sufficient to attain low RA disease activity at 12 weeks, in RA patients with moderate to severe disease (DAS28 ≥ 4.4 and US34-PDUS ≥ 10). TRIAL REGISTRATION: ClinicalTrials.gov NCT01717859 Key Points • Over 90% of RA patients with baseline DAS28-ESR ≥ 4.4 and PDUS34 ≥ 10 required intravenous tocilizumab dose escalation from 4 to 8 mg/kg at 12 weeks. • Reduction in power Doppler ultrasonography (US34-PDUS) scores correlate with DAS28-ESR and CDAI over 24 weeks in rheumatoid arthritis patients with moderate to severe disease activity. • Baseline US34-PDUS predicts future improvements in clinical disease activity outcomes, independent of baseline DAS28-ESR. • Clinical response measures, DAS28-ESR and CDAI, improved across US34-PDUS 20/50/70 categories, while patient-reported outcomes did not.

Validation of Sonography findings of synovitis and tenosynovitis of hands and wrists in patients with systemic sclerosis.

Objectives: Validating musculoskeletal ultrasound features of the joints and tendons of the hands in a large scleroderma cohort. Methods: A total of 81 scleroderma patients participated in this prospective, cross-sectional study. Grayscale and power Doppler musculoskeletal ultrasound images of 13 joints and 5 tendons of the wrist and hand were obtained. Clinical assessment included modified Rodnan skin thickness score, joint count, and Scleroderma Health Assessment Questionnaire. Face validity, content validity, construct validity, and feasibility were assessed. Results: Mean age was 53.8 years (range 22-80), 76.5% were females, and disease duration ranged from 0.25 to 29 years. Mean length of the examination was 36 min. Scleroderma Health Assessment Questionnaire-Disability Index correlated with musculoskeletal ultrasound erosions (r = 0.5, p = 0.0003). Skin score correlated with tendinitis grayscale (r = 0.26, p = 0.02). Intra-reader correlation coefficient for musculoskeletal ultrasound was 0.96 for the joints and could not be calculated for tendons because there were too few positive findings. When tendon changes existed, percent of agreement was 77.7%-83.3%. Conclusion: Musculoskeletal ultrasound of 13 joints and 5 tendons of the hands and wrist has face and content validity. Construct validity was shown for the tendons and erosion scores. Feasibility and reliability were partially validated.

Floating Tophi in a Baker Cyst Secondary to Gout: Ultrasound Features and Differential Diagnosis.

We report the case of a 36-year-old man with a recent diagnosis of gout, who presents with a fullness behind his right knee that fluctuates in size with time. An ultrasound revealed a Baker cyst that contained both large and punctate internal hyperechoic foci. Cyst aspiration revealed negatively birefringent crystals, which were consistent with gout.