Defining inflammatory musculoskeletal manifestations in systemic lupus erythematosus

Advanced imaging in the evaluation of lupus arthritis: A systematic literature review and meta-analysis

INTRODUCTION

Joint involvement is present in up to 95 % of patients with SLE. Arthritis is a main cause of work-related disability and 70-80 % of lupus patients in clinical trials have active joint manifestations.

OBJECTIVE

To review the evidence on the application of musculoskeletal (MSK) ultrasound (US), magnetic resonance imaging (MRI), and optical imaging (OI) in patients with SLE hand and wrist arthritis, discuss measurement properties of US, MRI, and OI, and to provide combined results from these studies.

METHODS

For this systematic review, three separate population, intervention, comparator, and outcome structured (PICOS) literature searches were conducted for US, MRI and OI using PubMed, EMBASE and the Cochrane Library. The search for US was restricted for the period Jan 1, 2019, to March 31, 2024.

RESULTS

Of the 502 identified articles for MSK US, 16 were included. Of the 2101 identified articles for MRI, only 8 were included. Of the 20 identified articles for OI, 1 was included. Data on the use of MSK US, MRI, and OI were evaluated separately regarding reported imaging abnormalities, the definition and scoring of these abnormalities, and measurement properties. Pooled analysis showed strong association between arthritis/arthralgia and US synovitis (10.89 [4.02, 29.48]) and tenosynovitis (5.93 [1.99, 17.72]); association between joint symptoms and US synovitis decreased to 5.00 (1.11, 22.60) when restricted to physician confirmed arthritis.

CONCLUSION

The current systematic literature review examined available information on the use of advanced imaging modalities in the evaluation of hand and wrist involvement in SLE. This literature review demonstrates the need for further research to substantiate the use of advanced imaging as an outcome measure for the MSK manifestations in patients with SLE.

The role of ultrasound and magnetic resonance imaging in the assessment of musculoskeletal involvement in systemic lupus erythematosus: A review of recent advances and insights

Systemic lupus erythematosus (SLE) is an autoimmune disease characterized by diverse manifestations, with musculoskeletal (MSK) involvement being one of the most prevalent and debilitating. Traditional perceptions of SLE arthritis as mild and primarily non-erosive are increasingly challenged by advanced imaging techniques, such as ultrasound and magnetic resonance imaging (MRI). These modalities have revealed subclinical inflammatory changes, structural damage, and peri-articular soft tissue involvement in both symptomatic and asymptomatic patients. Ultrasound is highly sensitive in detecting synovitis, tenosynovitis, and entheseal abnormalities, also in patients without clinical arthritis, offering insights into subclinical disease activity that would otherwise remain undiagnosed. MRI, while less commonly used due to cost and accessibility, remains the gold standard for detecting bone marrow oedema, subtle erosions, and inflammatory changes. Recent studies demonstrate that subclinical synovitis and tenosynovitis, identified through imaging, may precede clinical symptoms in some patients, emphasizing the potential prognostic value of these findings. Bone erosions, once thought rare in SLE, are now observed across various arthropathy subtypes, challenging traditional classifications. Imaging has also revealed the presence of entheseal and muscle involvement, expanding the understanding of SLE-related MSK pathology. This review highlights the transformative role of ultrasound and MRI in diagnosing, monitoring, and managing MSK involvement in SLE. Incorporating imaging findings into routine practice and updated classification criteria may enable early intervention and personalized treatment. While significant advancements have been made in imaging technologies for detecting musculoskeletal involvement in SLE, challenges remain in standardizing protocols and correlating findings with disease activity and outcomes. Further research is needed to address these challenges and further explore the prognostic significance of imaging findings.

A Case of Lupus Myopericarditis in a Young African American Male

A 28-year-old African American male presented to the emergency department with a chief complaint of chest pain. He stated that the pain began five days prior to arrival and had not improved despite taking ibuprofen and self-medicating with marijuana. His chest pain was constant and localized to the center of his chest, rating it as a 7/10 in terms of severity. His past medical history included a diagnosis of systemic lupus erythematosus (SLE) three months ago, complicated by pericarditis, for which he had been taking colchicine and prednisone, as well as hydroxychloroquine for maintenance therapy. He stated that he adhered to his treatment regimen without missing a single dosage. Upon cardiac auscultation, he was found to have a pericardial friction rub. His ECG showed signs of PR-segment depression in all leads, ST-elevation in leads V2-V4, as well as sinus tachycardia, raising some concern for myocardial ischemia. His echocardiogram showed no signs of pericardial effusion or left ventricular dysfunction and was otherwise unremarkable. Because of his positional chest pain, diffuse ST-elevation, and elevated troponin, the patient was diagnosed with myopericarditis, thought to be secondary to SLE exacerbation due to no recent illnesses. He was then placed on low-dose prednisone. After four days, his symptoms resolved, and he was discharged with a regimen of 60 mg prednisone daily and 0.5 mg colchicine daily for his pericarditis as well as 10 mg oxycodone for his pain every eight hours. His prednisone was to be tapered with a rheumatologist outpatient, but there was no follow-up at the time of writing this study.

Practical Use of Ultrasound in Modern Rheumatology-From A to Z

During the past 20 years, the use of ultrasound (US) in rheumatology has increased tremendously, and has become a valuable tool in rheumatologists' hands, not only for assessment of musculoskeletal structures like joints and peri-articular tissues, but also for evaluation of nerves, vessels, lungs, and skin, as well as for increasing the accuracy in a number of US-guided aspirations and injections. The US is currently used as the imaging method of choice for establishing an early diagnosis, assessing disease activity, monitoring treatment efficacy, and assessing the remission state of inflammatory joint diseases. It is also used as a complementary tool for the assessment of patients with degenerative joint diseases like osteoarthritis, and in the detection of crystal deposits for establishing the diagnosis of metabolic arthropathies (gout, calcium pyrophosphate deposition disease). The US has an added value in the diagnostic process of polymyalgia rheumatica and giant-cell arteritis, and is currently included in the classification criteria. A novel use of US in the assessment of the skin and lung involvement in connective tissue diseases has the potential to replace more expensive and risky imaging modalities. This narrative review will take a close look at the most recent evidence-based data regarding the use of US in the big spectrum of rheumatic diseases.

Subclinical synovitis impact on the progression of lupus joint disease: A 10-year longitudinal multicenter study

OBJECTIVE

To determine the effect of subclinical synovitis on the progression of joint disease in a cohort of patients with systemic lupus erythematosus over a mean follow-up of 10 years.

METHODS

A longitudinal follow-up of 96 patients diagnosed with lupus was performed. All patients were considered clinically free of joint disease or with minimal joint impairment at baseline and were studied through ultrasound study of their dominant hand to assess the prevalence of subclinical synovitis. Now, over 10 years after we contacted them and reviewed their evolution to determine the impact of had or had not been diagnosed with subclinical synovitis in their current joint condition.

RESULTS

Thirty-one of the 91 reached patients developed clinical progression in their joint manifestations (at least one ordinal degree of worsening). Of these, 23 (74,9%) had demonstrated subclinical synovitis at baseline. In the group of patients who did not progress clinically, 46 (76,6%) did not have this finding at the start of follow-up (p < .01, OR 9,44 95%CI 3,46-25,74). The patients in whom clinical progression was demonstrated had worse combined ultrasound scores than the rest of the patients: 6,41 SD 1,45 vs. 1,15 SD 0,97 (p < .01).

CONCLUSIONS

The finding of subclinical synovitis in patients with systemic lupus erythematosus is associated with the development of joint disease progression both clinically and ultrasonographically.

Revision to the musculoskeletal domain of the BILAG-2004 index to incorporate ultrasound findings

OBJECTIVES

To improve the definitions of inflammatory arthritis within the musculoskeletal (MSK) domain of the BILAG-2004 index by incorporating imaging findings and clinical features predictive of response to treatment.

METHODS

The BILAG MSK Subcommittee proposed revisions to the BILAG-2004 index definitions of inflammatory arthritis, based on review of evidence in two recent studies. Data from these studies were pooled and analysed to determine the impact of the proposed changes on the severity grading of inflammatory arthritis.

RESULTS

The revised definition for severe inflammatory arthritis includes definition of 'basic activities of daily living'. For moderate inflammatory arthritis, it now includes synovitis, defined by either observed joint swelling or MSK US evidence of inflammation in joints and surrounding structures. For mild inflammatory arthritis, the definition now includes reference to symmetrical distribution of affected joints and guidance on how US may help re-classify patients as moderate or no inflammatory arthritis. Data from two recent SLE trials were analysed (219 patients). A total of 119 (54.3%) were graded as having mild inflammatory arthritis (BILAG-2004 Grade C). Of these, 53 (44.5%) had evidence of joint inflammation (synovitis or tenosynovitis) on US. Applying the new definition increased the number of patients classified as moderate inflammatory arthritis from 72 (32.9%) to 125 (57.1%), while patients with normal US (n = 66/119) could be recategorized as BILAG-2004 Grade D (inactive disease).

CONCLUSIONS

Proposed changes to the definitions of inflammatory arthritis in the BILAG-2004 index will result in more accurate classification of patients who are more or less likely to respond to treatment.

Musculoskeletal manifestations of systemic lupus erythematosus

MSK is the most common and impactful symptom of lupus at a population level. It has a variety of different presentations, but joint swelling is often not present despite imaging-proven synovitis. Imaging with US and MRI has been shown to improve detection of inflammation and identify treatment-responsive patients. In contrast, the SLEDAI shows poor sensitivity, specificity, and responsiveness. While BILAG and SLE-DAS are superior, they are still less accurate than imaging. These issues may explain why the evidence for conventional and biologic therapies for MSK lupus is complex. In clinical practice, physicians must take care not to underestimate MSK inflammation and consider using imaging. Future research should investigate new therapeutic targets specifically for synovitis and more sensitive outcome measures and trials to evaluate them.

Assessment of disease activity and damage in SLE: Are we there yet?

Systemic Lupus Erythematosus is a systemic autoimmune disease characterized by a great heterogenicity in course and clinical manifestations. Although prognosis improved in the last decades of the 20th century, mortality remains higher than in the general population and uncontrolled disease activity and therapy-related adverse effects have been identified as major contributors to damage accrual and poor outcomes. Assessment of disease activity and damage in SLE represents a great challenge even to the expert rheumatologist. Global disease activity indices are tools developed to assess activity across multiple organ systems. Several disease activity indices have been developed over the years, each with its own strengths and weaknesses, and knowing them is essential for understanding research studies, such as clinical trials, in which they are used. Organ-specific activity indices have been developed concurrently to represent organ involvement such as glomerulonephritis, cutaneous and musculoskeletal lupus manifestations. Regarding damage, the SLICC/ACR damage index has proven to be an effective tool for damage accrual assessment, yet not devoid of drawbacks. This review provides an overview of the most frequently utilized indices developed for the assessment of activity and damage in SLE highlighting their pros and cons when applied to the research and clinical setting.

Improving measures of disease activity in systemic lupus erythematosus

INTRODUCTION

Systemic lupus erythematosus (SLE) is a multisystem disease with varied manifestations and course. Variation in presentation among patients, and within the same patient, there may be varied manifestations over time. It has been difficult to measure the extent of disease activity accurately. Several investigators and groups have developed definitions of disease activity and methods to measure it. Consequently, there are currently several instruments to measure disease activity as well as damage in patients with SLE.

AREAS COVERED

This review covers currently available evidence on measures of disease activity in SLE. It discusses potential avenues for further development of new measures and the refinement of existing tools to improve disease activity measures in research and clinical care settings.

EXPERT OPINION

Given the complexity and heterogeneity of the disease, further work and tools are needed to assess disease activity better. Organ-specific measures for cutaneous, renal, and joint manifestations are needed for a detailed assessment of disease activity in conjunction with the use of disease generic tools (e.g. SLEDAI). New tools such as the SLE Disease Activity Index-Glucocorticoid Index (SLEDAI-2 KG) incorporating glucocorticoid doses to describe disease activity, SLE-DAS and SLEDAI-2 K RI-50 to record partial improvements could also be helpful.

Current Progress in Treating Systemic Lupus Erythematosus Using Exosomes/MicroRNAs

Systemic lupus erythematosus (SLE) is a chronic systemic autoimmune disease associated with impaired organ functions that can seriously affect the daily life of patients. Recent SLE therapies frequently elicit adverse reactions and side effects in patients, and clinical heterogeneity is considerable. Mesenchymal stromal cells (MSCs) have anti-inflammatory, tissue repair, and immunomodulatory properties. Their ability to treat autoimmune diseases largely depends on secreted extracellular vesicles, especially exosomes. The effects of exosomes and microRNAs (miRNAs) on SLE have recently attracted interest. This review summarizes the applications of MSCs derived from bone marrow, adipocyte tissue, umbilical cord, synovial membrane, and gingival tissue, as well as exosomes to treating SLE and the key roles of miRNAs. The efficacy of MSCs infusion in SLE patients with impaired autologous MSCs are reviewed, and the potential of exosomes and their contents as drug delivery vectors for treating SLE and other autoimmune diseases in the future are briefly described.

Emerging concepts of type I interferons in SLE pathogenesis and therapy

Type I interferons have been suspected for decades to have a crucial role in the pathogenesis of systemic lupus erythematosus (SLE). Evidence has now overturned several long-held assumptions about how type I interferons are regulated and cause pathological conditions, providing a new view of SLE pathogenesis that resolves longstanding clinical dilemmas. This evidence includes data on interferons in relation to genetic predisposition and epigenetic regulation. Importantly, data are now available on the role of interferons in the early phases of the disease and the importance of non-haematopoietic cellular sources of type I interferons, such as keratinocytes, renal tubular cells, glial cells and synovial stromal cells, as well as local responses to type I interferons within these tissues. These local effects are found not only in inflamed target organs in established SLE, but also in histologically normal skin during asymptomatic preclinical phases, suggesting a role in disease initiation. In terms of clinical application, evidence relating to biomarkers to characterize the type I interferon system is complex, and, notably, interferon-blocking therapies are now licensed for the treatment of SLE. Collectively, the available data enable us to propose a model of disease pathogenesis that invokes the unique value of interferon-targeted therapies. Accordingly, future approaches in SLE involving disease reclassification and preventative strategies in preclinical phases should be investigated.

Anifrolumab efficacy and safety by type I interferon gene signature and clinical subgroups in patients with SLE: post hoc analysis of pooled data from two phase III trials

OBJECTIVES

To characterise the efficacy and safety of anifrolumab in patients with systemic lupus erythematosus (SLE) according to interferon gene signature (IFNGS), demographic and clinical subgroups.

METHODS

We performed post hoc analyses of pooled data from the 52-week phase III TULIP-1/TULIP-2 placebo-controlled trials of intravenous anifrolumab in moderate-to-severe SLE. Outcomes were assessed in predefined subgroups: IFNGS (high/low), age, sex, body mass index, race, geographic region, age of onset, glucocorticoid use, disease activity and serological markers.

RESULTS

In pooled data, patients received anifrolumab 300 mg (360/726) or placebo (366/726); 82.6% were IFNGS-high. IFNGS-high patients had greater baseline disease activity and were more likely to have abnormal serological markers versus IFNGS-low patients. In the total population, a greater proportion of patients treated with anifrolumab versus placebo achieved British Isles Lupus Assessment Group-based Composite Lupus Assessment (BICLA) response at week 52 (difference 16.6%; nominal p<0.001). BICLA response treatment differences with anifrolumab versus placebo were comparable to the total population across most predefined subgroups, including subgroups for baseline glucocorticoid dosage (<10/≥10 mg/day prednisone/equivalent) and for clinical disease activity (SLE Disease Activity Index 2000 score <10/≥10). Subgroups with larger treatment differences included IFNGS-high patients (18.2%), patients with abnormal baseline serological markers (23.1%) and Asian patients (29.2%). The safety profile of anifrolumab was similar across subgroups.

CONCLUSIONS

Overall, this study supports the consistent efficacy and safety of anifrolumab across a range of patients with moderate-to-severe SLE. In a few subgroups, small sample sizes limited conclusions from being drawn regarding the treatment benefit with anifrolumab.

TRIAL REGISTRATION NUMBER

NCT02446912, NCT02446899.

A Narrative Literature Review Comparing the Key Features of Musculoskeletal Involvement in Rheumatoid Arthritis and Systemic Lupus Erythematosus

Although the clinical approach to the management of musculoskeletal manifestations in systemic lupus erythematosus (SLE) is often similar to that of rheumatoid arthritis (RA), there are distinct differences in immunopathogenesis, structural and imaging phenotypes and therapeutic evidence. Additionally, there are few published comparisons of these diseases. The objective of this narrative literature review is to compare the immunopathogenesis, structural features, magnetic resonance imaging (MRI) and musculoskeletal ultrasound (MSUS) studies and management of joint manifestations in RA and SLE. We highlight the key similarities and differences between the two diseases. Overall, the literature evaluated indicates that synovitis and radiographical progression are the key features in RA, while inflammation without swelling, tendinitis and tenosynovitis are more prominent features in SLE. In addition, the importance of defining patients with RA by the presence or absence of autoantibodies and categorizing patients with SLE by synovitis detected by musculoskeletal ultrasound and by structural phenotype (non-deforming, non-erosive arthritis, Jaccoud’s arthropathy and ‘Rhupus’) with respect to joint manifestations will also be discussed. An increased understanding of the joint manifestations in RA and SLE may inform evidence-based clinical decisions for both diseases.

A glimpse into the future of systemic lupus erythematosus

This viewpoint article on a forecast of clinically meaningful changes in the management of systemic lupus erythematosus (SLE) in the next 10 years is based on a review of the current state of the art. The groundwork has been laid by a robust series of classification criteria and treatment recommendations that have all been published since 2019. Building on this strong foundation, SLE management predictably will take significant steps forward. Assessment for lupus arthritis will presumably include musculoskeletal sonography. Large-scale polyomics studies are likely to unravel more of the central immune mechanisms of the disease. Biomarkers predictive of therapeutic success may enter the field; the type I interferon signature, as a companion for use of anifrolumab, an antibody against the common type I interferon receptor, is one serious candidate. Besides anifrolumab for nonrenal SLE and the new calcineurin inhibitor voclosporin in lupus nephritis, both of which are already approved in the United States and likely to become available in the European Union in 2022, several other approaches are in advanced clinical trials. These include advanced B cell depletion, inhibition of costimulation via CD40 and CD40 ligand (CD40L), and Janus kinase 1 (Jak1) and Tyrosine kinase 2 (Tyk2) inhibition. At the same time, essentially all of our conventional therapeutic armamentarium will continue to be used. The ability of patients to have successful SLE pregnancies, which has become much better in the last decades, should further improve, with approaches including tumor necrosis factor blockade and self-monitoring of fetal heart rates. While we hope that the COVID-19 pandemic will soon be controlled, it has highlighted the risk of severe viral infections in SLE, with increased risk tied to certain therapies. Although there are some data that a cure might be achievable, this likely will remain a challenge beyond 10 years from now.

Ultrasound to identify systemic lupus erythematosus patients with musculoskeletal symptoms who respond best to therapy: the US Evaluation For mUsculoskeletal Lupus longitudinal multicentre study

OBJECTIVES

To determine whether SLE patients with inflammatory joint symptoms and US synovitis/tenosyovitis achieve better clinical responses to glucocorticoids compared with patients with normal scans. Secondary objectives included identification of clinical features predicting US synovitis/tenosynovitis.

METHODS

In a longitudinal multicentre study, SLE patients with physician-diagnosed inflammatory joint pain received intramuscular methylprednisolone 120 mg once. Clinical assessments, patient-reported outcomes and bilateral hand/wrist USs were collected at 0, 2 and 6 weeks. The primary outcome (determined via internal pilot) was the early morning stiffness visual analogue scale (EMS-VAS) at 2 weeks, adjusted for baseline, comparing patients with positive (greyscale ≥2 and/or power Doppler ≥1) and negative US. Post hoc analyses excluded FM.

RESULTS

Of 133 patients, 78 had a positive US. Only 53 (68%) of these had one or more swollen joint. Of 66 patients with one or more swollen joint, 20% had a negative US. A positive US was associated with joint swelling, symmetrical small joint distribution and serology. The primary endpoint was not met: in the full analysis set (N = 133) there was no difference in baseline-adjusted EMS-VAS at week 2 [-7.7 mm (95% CI -19.0, 3.5); P = 0.178]. After excluding 32 patients with FM, response was significantly better in patients with a positive US at baseline [baseline-adjusted EMS-VAS at 2 weeks -12.1 mm (95% CI -22.2, -0.1); P = 0.049]. This difference was greater when adjusted for treatment [-12.8 mm (95% CI -22, -3); P = 0.007]. BILAG and SLEDAI responses were higher in US-positive patients.

CONCLUSION

In SLE patients without FM, those with a positive US had a better clinical response to therapy. Imaging-detected synovitis/tenosynovitis may be considered to decide on therapy and enrich clinical trials.

Erosive arthritis in systemic lupus erythematosus: not only Rhupus

Systemic lupus erythematosus (SLE)-related arthritis has been traditionally defined as non-erosive and is therefore considered a minor manifestation requiring a mild treatment. However, the concept of non-erosive arthritis in SLE has been challenged with the advent of sensitive imaging techniques, such as high-resolution ultrasound with power Doppler or magnetic resonance. The application of these new imaging tools has demonstrated that up to 40% of SLE patients with joint involvement can develop erosive damage. Thus, this more aggressive phenotype can be identified not only in patients overlapping with rheumatoid arthritis (RA). This issue has been considered for the first time in the classification criteria proposed by Systemic Lupus International Collaborating Clinics in 2012, in which the old definition of "non-erosive arthritis" was replaced with either synovitis or tenderness in two or more joints with morning stiffness, suggesting the possible presence of an erosive phenotype. Accordingly, the 2019 EULAR/ACR's SLE recommendations advise treatment with immunosuppressant or biological drugs for patients with RA-like moderate arthritis. As a result, several studies have investigated the presence of biomarkers associated with SLE erosive damage. A relevant role seems to be played by the autoantibodies directed against post-translational modified proteins: above all, a significant association has been observed with antibodies directed against citrullinated and carbamylated proteins. Conversely, the rheumatoid factor was not associated with this more aggressive SLE-related arthritis. Nonetheless, some pro-inflammatory factors have been associated with erosive damage in SLE patients. These results suggest new pathogenic mechanisms underlining erosive arthritis, only partially shared with RA. Hence, in the present narrative review, we summarized available data about erosive arthritis in SLE patients, in the light of its impact on therapeutic decisions.

Impaired hand function and performance in activities of daily living in systemic lupus erythematosus, even in patients achieving lupus low disease activity state (LLDAS)

Objective

The aim was to examine hand function and performance in activities of daily living (ADL) in patients with SLE vs healthy controls, and any associations with demographic and disease-related characteristics.

Methods

Hand function (grip strength, pinch strength and dexterity) and ADL performance were evaluated in 240 patients with SLE and 122 age- and biological sex-matched healthy controls. Grip strength, pinch strength and dexterity were measured by Jamar dynamometer, pinch gauge and Purdue pegboard test, respectively. Self-reported ADL performance was assessed by disabilities of the arm, shoulder and hand (DASH) and HAQ. Regression analysis was performed to assess the determinants of hand dysfunction.

Results

All hand function and ADL performance variables were significantly impaired in the entire SLE cohort and the subgroup of patients achieving lupus low disease activity state (LLDAS; n = 157) compared with healthy subjects (P < 0.05). Joint pain, often underestimated in SLE, was the major determinant of hand function and ADL performance in multiple regression models. In addition, age was correlated with grip strength and Purdue scores, gender with grip strength, arthritis with DASH and HAQ, and use of immunosuppressives with DASH, HAQ and grip strength. Likewise, in patients in LLDAS, painful joints were correlated with DASH and HAQ, age with grip strength and Purdue (P < 0.001), gender with grip strength, and immunosuppressives with HAQ and grip strength.

Conclusion

Hand function and performance of daily activities are significantly impaired in SLE, even in patients who achieve LLDAS, suggesting the need for their evaluation and management in clinical practice.

Imaging of Joint and Soft Tissue Involvement in Systemic Lupus Erythematosus

PURPOSE OF REVIEW

To highlight the potential uses and applications of imaging in the assessment of the most common and relevant musculoskeletal (MSK) manifestations in systemic lupus erythematosus (SLE).

RECENT FINDINGS

Ultrasound (US) and magnetic resonance imaging (MRI) are accurate and sensitive in the assessment of inflammation and structural damage at the joint and soft tissue structures in patients with SLE. The US is particularly helpful for the detection of joint and/or tendon inflammation in patients with arthralgia but without clinical synovitis, and for the early identification of bone erosions. MRI plays a key role in the early diagnosis of osteonecrosis and in the assessment of muscle involvement (i.e., myositis and myopathy). Conventional radiography (CR) remains the traditional gold standard for the evaluation of structural damage in patients with joint involvement, and for the study of bone pathology. The diagnostic value of CR is affected by the poor sensitivity in demonstrating early structural changes at joint and soft tissue level. Computed tomography allows a detailed evaluation of bone damage. However, the inability to distinguish different soft tissues and the need for ionizing radiation limit its use to selected clinical circumstances. Nuclear imaging techniques are valuable resources in patients with suspected bone infection (i.e., osteomyelitis), especially when MRI is contraindicated. Finally, dual energy X-ray absorptiometry represents the imaging mainstay for the assessment and monitoring of bone status in patients with or at-risk of osteoporosis. Imaging provides relevant and valuable information in the assessment of MSK involvement in SLE.

European League Against Rheumatism (EULAR)/American College of Rheumatology (ACR) SLE classification criteria item performance

BACKGROUND/OBJECTIVES

The European League Against Rheumatism (EULAR)/American College of Rheumatology (ACR) 2019 classification criteria for systemic lupus erythematosus system showed high specificity, while attaining also high sensitivity. We hereby analysed the performance of the individual criteria items and their contribution to the overall performance of the criteria.

METHODS

We combined the EULAR/ACR derivation and validation cohorts for a total of 1197 systemic lupus erythematosus (SLE) and n=1074 non-SLE patients with a variety of conditions mimicking SLE, such as other autoimmune diseases, and calculated the sensitivity and specificity for antinuclear antibodies (ANA) and the 23 specific criteria items. We also tested performance omitting the EULAR/ACR criteria attribution rule, which defines that items are only counted if not more likely explained by a cause other than SLE.

RESULTS

Positive ANA, the new entry criterion, was 99.5% sensitive, but only 19.4% specific, against a non-SLE population that included other inflammatory rheumatic, infectious, malignant and metabolic diseases. The specific criteria items were highly variable in sensitivity (from 0.42% for delirium and 1.84% for psychosis to 75.6% for antibodies to double-stranded DNA), but their specificity was uniformly high, with low C3 or C4 (83.0%) and leucopenia <4.000/mm³ (83.8%) at the lowest end. Unexplained fever was 95.3% specific in this cohort. Applying the attribution rule improved specificity, particularly for joint involvement.

CONCLUSIONS

Changing the position of the highly sensitive, non-specific ANA to an entry criterion and the attribution rule resulted in a specificity of >80% for all items, explaining the higher overall specificity of the criteria set.

Arthritis in systemic lupus erythematosus is characterized by local IL-17A and IL-6 expression in synovial fluid

Arthritis is a common clinical feature of systemic lupus erythematosus (SLE) and is usually non‐erosive, as opposed to rheumatoid arthritis (RA). While RA synovial pathology has been extensively studied, little is known about the pathophysiology of lupus arthritis. Here, we aimed to explore the cytokine and cellular compartments in synovial fluids of SLE patients with arthritic manifestations. Acellular synovial fluid and paired serum samples from SLE patients (n = 17) were analyzed with cytokine bead array for T helper‐associated cytokines. From two SLE patients, synovial fluid mononuclear cells (SFMC) could also be captured and were analyzed by multiparameter flow cytometry to dissect T cell, B cell, monocyte and dendritic cell phenotypes. SLE‐derived SFMC were further stimulated in vitro to measure their capacity for producing interferon (IFN)‐γ and interleukin (IL)‐17A. All patients fulfilled the ACR 1982 classification criteria for SLE. Clinical records were reviewed to exclude the presence of co‐morbidities such as osteoarthritis or overlap with RA. IL‐17A and IL‐6 levels were high in SLE synovial fluid. A clear subset of the synovial CD4⁺ T cells expressed CCR6⁺, a marker associated with T helper type 17 (Th17) cells. IL‐17A‐production was validated among CD4⁺CCR6⁺ T cells following in‐vitro stimulation. Furthermore, a strong IFN‐γ production was observed in both CD4⁺ and CD8⁺ cells. Our study shows high IL‐17A and IL‐6 levels in synovial fluids of patients with lupus arthritis. The Th17 pathway has been implicated in several aspects of SLE disease pathogenesis and our data also point to Th17 involvement for lupus arthritis.

Classifying and diagnosing systemic lupus erythematosus in the 21st century

The EULAR/ACR 2019 classification criteria for SLE constitute a current and optimized clinical approach to SLE classification. Classification is still not based on molecular approaches and the results from large studies using polyomics may be interpreted as demonstrating the relevance of the genetic and environmental background rather than splitting SLE into several entities. In fact, an association study within the EULAR/ACR classification criteria project found associations between manifestations only within organ domains. This independency of various organ manifestations argues for SLE as one disease entity. The current review article will therefore concentrate on the clinical and immunological manifestations of SLE and on what we have already learned in this century. Moreover, the structure and essential rules of the EULAR/ACR 2019 classification criteria will be discussed. While classification and diagnosis are distinct concepts, which have to remain clearly separated, information derived from the process towards the classification criteria is also useful for diagnostic purposes. Therefore this article also tries to delineate what classification can teach us for diagnosis, covering a wide variety of SLE manifestations.

Involvement of the wrist and hand joints and tendons in an Egyptian systemic lupus erythematosus cohort

Background

Systemic lupus erythematosus (SLE) patients often suffer hand function limitations even in the absence of symptoms related to joint or tendon disorders. Recent researches reported the presence of ultrasonographic (US) subclinical synovitis and tendon involvement in asymptomatic patients. We aimed to assess US patterns in SLE patients and determine their relationship with clinical assessment, disease activity and hand functional status using handheld dynamometry.

Results

We assessed 30 SLE patients (60 hands) using US; 21 (70%) patient had synovial hypertrophy, 8 (26%) showed a power Doppler (PD) activity, 6 (20%) had erosions and 11 (36.6%) had tendon US abnormality. Both patients with hand arthralgia/arthritis (symptomatic) and patients without arthralgia/arthritis (asymptomatic) had a statistically insignificant difference regarding the global synovitis score (p= 0.2) and disease activity (p= 0.3). However, the symptomatic group had a significantly increased number of joints with effusion (p= 0.04) and tendons involved (p= 0.04). The mean grip strength had a significant negative correlation with SLEDAI-2 K score (rs = − 0.4,p= 0.02) in the total patient group. In the asymptomatic group, a negative correlation was found between both mean grip (rs = − 0.5,p= 0.04) and pinch strength (rs = − 0.6,p= 0.01) with PD index, and mean pinch strength with the Jaccoud’s arthropathy index (rs = − 0.49,p= 0.05).

Conclusions

SLE patients may have higher subclinical synovitis, erosions and tendon involvement than expected, which may in turn reduce hand grip and pinch strength. Disease activity may also have a negative impact on the hand grip functional strength.

Systemic lupus erythematosus: year in review 2019

Systemic lupus erythematosus (SLE) is an autoimmune disease with extreme heterogeneity and potentially involvement of any organ or system. Numerous unanswered questions and challenges in SLE always prompt further exploration. In 2019, great progress in various aspects of SLE emerged. Both the classification criteria and management recommendation for SLE were updated. New promising medications have been widely developed and tested, although subsequent clinical studies are warranted. As an emerging number of most notable studies in SLE were published in both clinical area and basic research in 2019, we aim to summarize the highest quality data on SLE regarding novel insights of pathogenesis, updated recommendations, hot-spot issues on clinical manifestations, new understanding of disease prognosis, and most importantly, the therapeutic advances in SLE in this review.

A Zebra at the Rodeo: Dyspnea, Hematuria, and a Family History of Arthritis

An 18-year-old, previously healthy female was admitted for urgent evaluation and management of symptomatic anemia after presenting to her primary care physician with fatigue and shortness of breath. The initial outpatient evaluation was remarkable for hypochromic, microcytic anemia with a hemoglobin of 6.7 g/dL.

Responsiveness of clinical and ultrasound outcome measures in musculoskeletal systemic lupus erythematosus

OBJECTIVE

To assess the responsiveness of clinical outcome measures in musculoskeletal SLE compared with US.

METHODS

A prospective pilot study was conducted in consecutive SLE patients with inflammatory musculoskeletal symptoms. Clinical assessments including SLEDAI, BILAG, 28 tender and swollen joint counts, physician and patient visual analogue scales (VAS), and US were performed at 0, 2 and 4 weeks following 120 mg i.m. methylprednisolone acetate. Responsiveness was analysed using changes and effect sizes using Cohen's criteria.

RESULTS

Twenty patients were recruited. Fifteen out of 20 had clinical swelling at baseline. All clinical and US parameters were significantly improved at week 4 (all P ⩽ 0.01). Musculoskeletal-BILAG score improved in 16/20. Musculoskeletal-SLEDAI improved in 7/20. SLE responder index 4 criteria were assessed in 19 patients with SLEDAI ⩾4 at baseline and were met in 9/19 at 4 weeks. Effect sizes at 4 weeks were large (>0.5) for US, physician VAS and BILAG, and medium (>0.3) for joint counts and SLEDAI. Large effect sizes for improvement in US grey-scale and power Doppler were observed in both SLE responder index 4 responders (r = -0.51 and -0.56, respectively) and non-responders (r = -0.62 and -0.59, respectively) at 4 weeks.

CONCLUSION

This is the first study to measure the responsiveness of clinical outcome measures in musculoskeletal SLE against an objective inflammation measure. BILAG and physician VAS were the most responsive clinical instruments. US was highly responsive in musculoskeletal SLE, while SLEDAI and joint counts appeared suboptimal for detection of improvement. These results suggest that clinical trials based on the SLEDAI and SLE responder index 4 may underestimate the efficacy of therapy in SLE.