Classification criteria in rheumatic diseases: a review of methodologic properties

50 years of spondyloarthritis: a look back and a look ahead

PURPOSE OF REVIEW

It is now 50 years since the concept of spondyloarthritis was introduced by Moll, Wright and co-authors from Leeds, UK. This review will review the original concept and mark significant milestones over the last 50 years while looking ahead to developments in the future.

RECENT FINDINGS

While the diseases included under this rubric in the original description may have changed the core conditions remain and are still characterized by axial inflammation as a common feature. Imaging, animal models, genetics and immunology have contributed to our knowledge of the pathogenesis and classification of these diseases and have led to the development of more effective treatments.

SUMMARY

Future developments, facilitated by large research consortia, will help build on our current knowledge and will help clarify disease heterogeneity and provide insights into new therapeutic pathways.

2023 ACR/EULAR antiphospholipid syndrome classification criteria

OBJECTIVE

To develop new antiphospholipid syndrome (APS) classification criteria with high specificity for use in observational studies and trials, jointly supported by the American College of Rheumatology (ACR) and EULAR.

METHODS

This international multidisciplinary initiative included four phases: (1) Phase I, criteria generation by surveys and literature review; (2) Phase II, criteria reduction by modified Delphi and nominal group technique exercises; (3) Phase III, criteria definition, further reduction with the guidance of real-world patient scenarios, and weighting via consensus-based multicriteria decision analysis, and threshold identification; and (4) Phase IV, validation using independent adjudicators' consensus as the gold standard.

RESULTS

The 2023 ACR/EULAR APS classification criteria include an entry criterion of at least one positive antiphospholipid antibody (aPL) test within 3 years of identification of an aPL-associated clinical criterion, followed by additive weighted criteria (score range 1-7 points each) clustered into six clinical domains (macrovascular venous thromboembolism, macrovascular arterial thrombosis, microvascular, obstetric, cardiac valve, and hematologic) and two laboratory domains (lupus anticoagulant functional coagulation assays, and solid-phase enzyme-linked immunosorbent assays for IgG/IgM anticardiolipin and/or IgG/IgM anti-β2-glycoprotein I antibodies). Patients accumulating at least three points each from the clinical and laboratory domains are classified as having APS. In the validation cohort, the new APS criteria vs the 2006 revised Sapporo classification criteria had a specificity of 99% vs 86%, and a sensitivity of 84% vs 99%.

CONCLUSION

These new ACR/EULAR APS classification criteria were developed using rigorous methodology with multidisciplinary international input. Hierarchically clustered, weighted, and risk-stratified criteria reflect the current thinking about APS, providing high specificity and a strong foundation for future APS research.

The 2023 ACR/EULAR Antiphospholipid Syndrome Classification Criteria

OBJECTIVE

To develop new antiphospholipid syndrome (APS) classification criteria with high specificity for use in observational studies and trials, jointly supported by the American College of Rheumatology (ACR) and EULAR.

METHODS

This international multidisciplinary initiative included 4 phases: 1) Phase I, criteria generation by surveys and literature review; 2) Phase II, criteria reduction by modified Delphi and nominal group technique exercises; 3) Phase III, criteria definition, further reduction with the guidance of real-world patient scenarios, and weighting via consensus-based multicriteria decision analysis, and threshold identification; and 4) Phase IV, validation using independent adjudicators' consensus as the gold standard.

RESULTS

The 2023 ACR/EULAR APS classification criteria include an entry criterion of at least one positive antiphospholipid antibody (aPL) test within 3 years of identification of an aPL-associated clinical criterion, followed by additive weighted criteria (score range 1-7 points each) clustered into 6 clinical domains (macrovascular venous thromboembolism, macrovascular arterial thrombosis, microvascular, obstetric, cardiac valve, and hematologic) and 2 laboratory domains (lupus anticoagulant functional coagulation assays, and solid-phase enzyme-linked immunosorbent assays for IgG/IgM anticardiolipin and/or IgG/IgM anti-β2 -glycoprotein I antibodies). Patients accumulating at least 3 points each from the clinical and laboratory domains are classified as having APS. In the validation cohort, the new APS criteria versus the 2006 revised Sapporo classification criteria had a specificity of 99% versus 86%, and a sensitivity of 84% versus 99%.

CONCLUSION

These new ACR/EULAR APS classification criteria were developed using rigorous methodology with multidisciplinary international input. Hierarchically clustered, weighted, and risk-stratified criteria reflect the current thinking about APS, providing high specificity and a strong foundation for future APS research.

Eligibility Criteria of Participants in Randomized Controlled Trials Assessing Conservative Management of Cervical Radiculopathy: A Systematic Review

STUDY DESIGN

Systematic review.

OBJECTIVE

The aim of this study was to evaluate the inclusion and exclusion criteria for participants in randomized control trials (RCTs) assessing conservative management for cervical radiculopathy (CR), to determine if any consensus exists within the literature.

SUMMARY OF BACKGROUND DATA

A 2012 systematic review identified a lack of uniformity for the eligibility criteria of participants in RCTs evaluating conservative interventions for CR. Since then, a large number of RCTs have been published, signaling the need for an updated evaluation of this topic.

MATERIALS AND METHODS

We electronically searched MEDLINE, CENTRAL, CINAHL, Embase, and PsycINFO from inception to June 15, 2022, to identify RCTs assessing conservative management of CR. Information extracted was analyzed to determine the level of homogeneity and/or heterogeneity of the inclusion and exclusion criteria across studies.

RESULTS

Seventy-six RCTs met our inclusion criteria with 68 distinct trials identified. The inclusion of arm pain with or without another symptom ( i.e. numbness, paresthesia, or weakness) was required in 69.12% of trials, 50% of trials required participants to exhibit neck symptoms, and 73.53% of studies required some form of clinical examination findings, but inconsistencies existed for the number and type of tests used. Furthermore, 41.18% of trials included imaging, with 33.82% of trials requiring magnetic resonance imaging findings. The most common exclusion criteria included were the presence of red flags and cervical myelopathy in 66.18% and 58.82% of trials, respectively.

CONCLUSIONS

Overall, there is still a lack of uniformity for the inclusion/exclusion criteria of trials assessing the conservative management of CR, with some improvements noted compared with the 2012 review. Based on the current literature assessing the diagnostic utility of clinical symptoms and confirmatory tests, we proposed inclusion criteria for trials assessing conservative interventions. Future research should aim to develop standardized classification criteria to improve consistency among studies.

Approach to Systemic Sclerosis Patient Assessment

Systemic sclerosis (SSc) is a heterogeneous disease comprising of a wide spectrum of ages of onset, sex-based differences, ethnic variations, disease manifestations, differential serologic profiles, and variable response to therapy resulting in reduced health-related quality of life, disability, and survival. The ability to subset groups of patients with SSc can assist with refining the diagnosis, guide appropriate monitoring, inform aggressiveness of immunosuppression, and predict prognosis. The ability to subset patients with SSc has several important practical implications for patient care.

Advances in SLE classification criteria

This year, the American College of Rheumatology (ACR) 1982 classification criteria for systemic lupus erythematosus (SLE) celebrate their 40th anniversary. From this start, the quest for optimal SLE criteria has led to the 1997 ACR update, the 2012 publication of the Systemic Lupus International Collaborating Clinics (SLICC) criteria, and, in 2019, the European League Against Rheumatism (EULAR)/ACR classification criteria. The latter have since been externally validated in more than two dozen studies and have become the gold standard inclusion criterion of SLE clinical trials. This comprehensive review attempts to follow the evolving success story of SLE classification, highlighting relevant decisions and their rationale, and discussing consequences for the way SLE is defined and managed.

A Case of Chronic Lymphocytic Leukemia Complicated by Hemophagocytic Lymphohistiocytosis: Identifying the Aberrant Immune Response

Hemophagocytic lymphohistiocytosis (HLH) is a life-threatening hyperinflammatory syndrome that may complicate hematologic malignancies. HLH and malignancies have common clinical features, and HLH diagnostic criteria (HLH-2004/Hscore) were not validated in this specific population. We describe a case of a 72-year-old patient with a history of chronic lymphocytic leukemia stable for over 10 years who presented with fever and cytopenia. After excluding infectious etiologies and the progression of her disease, HLH was diagnosed. The patient was treated with etoposide, dexamethasone, intravenous immunoglobulin, and rituximab. Despite initial clinical improvement, the patient deteriorated and developed pulmonary aspergillosis and CNS involvement that reflected uncontrolled HLH. The patient died 45 days after her presentation. An unusual feature of this case was that HLH was not triggered by infection, disease transformation, or treatment. This case emphasizes the challenges of differentiating the development of overwhelming HLH from other complications associated with hematologic malignancy.

Multiparametric Large Field of View Rheumatology Imaging for Axial Spondyloarthropathy Detects Enthesitis in Setting of Inactive Sacroiliac Joint Disease and Impacts Clinical Diagnosis

AIM

To test the diagnostic efficacy of a multiparametric rheumatology lumbosacral magnetic resonance (MR) imaging protocol in detection and characterization of axial spondylarthritis (SpA) and compare it with serology and clinical findings.

METHODS

A consecutive series of multiparametric rheumatology lumbosacral MR imaging examinations performed on 3T MR scanner. Three-dimensional inversion recovery turbo spin echo, precontrast and postcontrast fat-suppressed T1-weighted images, as well as diffusion-weighted images were used to detect active erosions and enthesitis using established criteria. Pearson χ2 was used for categorical variables. Sensitivity, specificity, positive predictive value, negative predictive value, and accuracy were measured for magnetic resonance imaging (MRI) and serology, based on the final diagnosis from rheumatologists. An alpha error below 0.05 was considered statistically significant.

RESULTS

The final study sample included 130 consecutive patients (80 women and 50 men; mean ± SD 44 ± 13 and 45 ± 14 years, respectively). Seventy-eight subjects were diagnosed with axial SpA and 52 with non-SpA arthropathy. In the non-SpA group, 27 patients were diagnosed with osteoarthritis, 6 had unremarkable imaging, whereas 19 were considered as clinically undetermined. There was positive correlation between positive MRI results and SpA diagnosis (P < 0.00001). No correlation existed between positive serology alone and SpA diagnosis (P = 0.0634). Although MRI and serology proved equally sensitive in detecting SpA, the specificity and overall accuracy of MRI were significantly higher. Inflammatory activity was detected in 45 (57.7%) cases, in the pelvic enthesis in 29 (37.2%) cases, in the lumbosacral spine in 16 (20.5%) cases, in the hip joints in 15 (19.2%) cases, and in the pubic symphysis in 5 (6.4%). Inactive sacral disease was seen in 7 of 35 enthesitis patients (20.0%), and in 2 SpA cases, there were no sacral lesions.

CONCLUSIONS

The results suggest that in patients with suspected SpA, MRI should not be limited to the sacroiliac joints, but also include enthesitis sites and other joints of the axial skeleton. The multiparametric rheumatology protocol increases the efficacy of MRI in detecting enthesitis and joint inflammatory disease, thereby offering additional information to the clinician and assisting in the early diagnosis/detecting disease activity.

Classification of systemic lupus erythematosus in children and adults

Systemic Lupus Erythematosus (SLE) is an autoimmune multisystem disease with a variable clinical phenotype and no single clinical, laboratory or pathological feature that can be used as a gold standard for disease classification or diagnosis. Classification criteria have been developed in an attempt to define homogenous groups of SLE patients for clinical research. They have been mainly validated in adult cohorts, given the much lower prevalence of SLE before puberty. The three commonly used sets of current classification criteria and their validation studies to date are described in this review. Challenges relating to classification of SLE patients, including important differences across age-groups and ethnicities, are explored along with future directions in the classification of SLE.

Clinical application of mesenchymal stem cells in rheumatic diseases

Mesenchymal stem cells (MSCs) are pluripotent stem cells derived from mesoderm during early development that are characterized by high self-renewal ability and multidirectional differentiation potential. These cells are present various tissues in the human body and can be cultured in vitro. Under specific conditions, MSCs can differentiate into osteoblasts, neuron-like cells, adipocytes and muscle cells and so on, therefore, have a great application value in cell replacement therapy and tissue repair. In recent years, the application of MSCs in rheumatic diseases has received increasing attention. On the one hand, MSCs have the ability to differentiate into bone and cartilage cells; on the other hand, these stem cells are also involved in immune regulation, resulting in the alleviation of inflammation and anti-fibrotic properties and the promotion of vascular repair, thus bringing new hope for the treatment of rheumatic diseases. This article reviews the clinical progress in MSC application for the treatment of rheumatic diseases.

Systematic Analysis of the Literature in Search of Defining Systemic Sclerosis Subsets

OBJECTIVE

Systemic sclerosis (SSc) is a multisystem disease with heterogeneity in presentation and prognosis.An international collaboration to develop new SSc subset criteria is underway. Our objectives were to identify systems of SSc subset classification and synthesize novel concepts to inform development of new criteria.

METHODS

Medline, Cochrane MEDLINE, the Cumulative Index to Nursing and Allied Health Literature, EMBASE, and Web of Science were searched from their inceptions to December 2019 for studies related to SSc subclassification, limited to humans and without language or sample size restrictions.

RESULTS

Of 5686 citations, 102 studies reported original data on SSc subsets. Subset classification systems relied on extent of skin involvement and/or SSc-specific autoantibodies (n = 61), nailfold capillary patterns (n = 29), and molecular, genomic, and cellular patterns (n = 12). While some systems of subset classification confer prognostic value for clinical phenotype, severity, and mortality, only subsetting by gene expression signatures in tissue samples has been associated with response to therapy.

CONCLUSION

Subsetting on extent of skin involvement remains important. Novel disease attributes including SSc-specific autoantibodies, nailfold capillary patterns, and tissue gene expression signatures have been proposed as innovative means of SSc subsetting.

Clinical validation of the Oswestry-Bristol Classification as part of a decision algorithm for trochlear dysplasia surgery

AIMS

The Oswestry-Bristol Classification (OBC) is an MRI-specific assessment tool to grade trochlear dysplasia. The aim of this study is to validate clinically the OBC by demonstrating its use in selecting treatments that are safe and effective.

METHODS

The OBC and the patellotrochlear index were used as part of the Oswestry Patellotrochlear Algorithm (OPTA) to guide the surgical treatment of patients with patellar instability. Patients were assigned to one of four treatment groups: medial patellofemoral ligament reconstruction (MPFLr); MPFLr + tibial tubercle distalization (TTD); trochleoplasty; or trochleoplasty + TTD. A prospective analysis of a longitudinal patellofemoral database was performed. Between 2012 and 2018, 202 patients (233 knees) with a mean age of 24.2 years (SD 8.1), with recurrent patellar instability were treated by two fellowship-trained consultant sports/knee surgeons at The Robert Jones and Agnes Hunt Orthopaedic Hospital. Clinical efficacy of each treatment group was assessed by Kujala, International Knee Documentation Committee (IKDC), and EuroQol five-dimension questionnaire (EQ-5D) scores at baseline, and up to 60 months postoperatively. Their safety was assessed by complication rate and requirement for further surgery. The pattern of clinical outcome over time was analyzed using mixed regression modelling.

RESULTS

In all, 135 knees (mean age 24.9 years (SD 9.4)) were treated using a MPFLr. Ten knees (7.4%) required additional surgery. A total of 50 knees (mean age 24.4 years (SD 6.3)) were treated using MPFLr + TTD. Ten (20%) required additional surgery. A total of 20 knees (mean age 19.5 years (SD 3.0)) were treated using trochleoplasty + TTD. Three patients (15%) required additional surgery. In each treatment group, there was a significant improvement in Kujala, IKDC, and EQ-5D at one year postoperatively (p < 0.001) with a recognized level of overall complication rate.

CONCLUSION

The OBC is a valid assessment tool to grade patients with trochlear dysplasia and, when used as part of the OPTA, helps to determine treatments that are safe and effective. This fulfils the requirements for its application in mainstream clinical practice. Cite this article: Bone Joint J 2021;103-B(10):1586-1594.

Assessment of subclinical atherosclerosis with ankle-brachial index in psoriatic arthritis: A case-control study

Objectives

This study aims to evaluate subclinical atherosclerosis using the Ankle-Brachial Index (ABI) in patients with psoriatic arthritis (PsA).

Patients and methods

This case-control study included 51 PsA patients (24 males, 27 females; median age 47; range, 41 to 52 years) recruited at our hospital's outpatient clinics between October 2016 and January 2017 and 50 healthy controls (24 males, 26 females; median age: 48.5; range, 40.7 to 56 years). Anthropomorphic measurements and laboratory results were recorded. In patients, the 66 swollen/68 tender joints count, dactylitis score, Leeds Enthesitis Index, Health-related Quality of Life, the Psoriasis Area and Severity Index, and Dermatology Life Quality Index were evaluated. Ankylosing Spondylitis Quality of Life and Bath Ankylosing Spondylitis Disease Activity Index were applied to patients with axial disease. Then, Composite Psoriatic Disease Activity Index was determined. A Doppler probe and a standard blood pressure cuff were used to calculate the ABI values for each participant.

Results

Patients had lower right ABI (median, 1.05 vs. 1.1, p<0.01), lower left ABI (1.04 vs. 1.09, p<0.01) and lower overall ABI (1.03 vs. 1.09, p<0.01) compared with healthy subjects. Twelve (23.5%) patients had borderline ABI, but none of the controls (p<0.01). Patients with borderline ABI had a longer duration of psoriasis (25 vs. 15 years, p=0.03). The distribution of borderline ABI value was statistically significant between patients with axial disease and peripheral disease only (42.1% vs. 12.5%, p=0.02). Disease activity was found as an independent risk factor for borderline ABI in a binary logistic regression (odds ratio 6.306, 95% confidence interval 1.185 to 33.561, p=0.031).

Conclusion

Lower ABI was found in PsA patients than healthy controls even in those matched with traditional cardiovascular risk factors. All participants with borderline ABI were in the patient group. Borderline ABI was associated with disease activity and disease duration.

Autoantibody profiles delineate distinct subsets of scleromyositis

OBJECTIVE

Scleromyositis remains incompletely characterized owing in part to its heterogeneity. The purpose of this study was to explore the role of autoantibody profiles to define subsets of scleromyositis.

METHODS

Subjects with scleromyositis from a prospective cohort were divided into 3 groups based on autoantibody profiles: subjects with SSc-specific autoantibodies (anti-centromere, -topoisomerase 1, -RNA polymerase III, -Th/To, -fibrillarin), subjects with SSc-overlap autoantibodies (anti-PM/Scl, -U1RNP, -Ku), and subjects without SSc-related autoantibodies. Clinical features, laboratory tests, and histopathological findings were retrieved and compared between groups.

RESULTS

Of 42 scleromyositis subjects (79% female, mean age at diagnosis 55 years, mean disease duration 3.5 years), 8 (19%) subjects had SSc-specific autoantibodies, 14 (33%) SSc-overlap autoantibodies and 20 (48%) had no SSc-related autoantibodies. One-third had no skin involvement, a finding more frequent in the SSc-overlap subjects and those without SSc-related autoantibodies. Proximal and distal weakness was common and head drop/bent spine was found in 50% of the SSc-specific and 35% of the subjects without SSc-related autoantibodies. Of note, the group without SSc-related autoantibodies had the only cases of severe cardiac systolic dysfunction (n = 1) and scleroderma renal crisis (n = 1), as well as 3 out of the 4 cancers and 3 out of the 4 deaths.

CONCLUSION

In this carefully phenotyped series of scleromyositis subjects, absence of SSc-related autoantibodies was common and associated with distinct features and poor prognosis. Future studies are needed to validate these results and possibly identify novel autoantibodies or other biomarkers associated with scleromyositis.

Systemic Lupus Erythematosus Classification and Diagnosis

Since the European League Against Rheumatism/American College of Rheumatology 2019 classification criteria for systemic lupus erythematosus (SLE) were published, they were externally validated by groups worldwide. In particular, the new criteria worked well also in East Asian and pediatric cohorts. Antinuclear antibodies (ANA) as an entry criterion were critically discussed, but the group of ANA-negative patients is small (<5%) worldwide. Specificity of the criteria is dependent on correct attribution only of those criteria that are not better explained by other causes. Although the classification criteria should not be used for diagnosis, many novel aspects inform diagnostic considerations.

Combining Calcitonin and Procalcitonin and Rheumatoid Arthritis-Related Biomarkers Improve Diagnostic Outcomes in Early Rheumatoid Arthritis

Objective

To demonstrate whether procalcitonin (PCT) combined with calcitonin (CT) could provide additional diagnostic value to other clinically available rheumatoid arthritis- (RA-) related biomarkers in the early diagnosis of RA.

Method

The blood samples aseptically collected by venipuncture were centrifuged within 1 hour and frozen at -80°C. PCT and CT levels were measured using electrochemiluminescence immunoassay (ECLIA) in 260 subjects (48 patients with early RA, 34 patients with established RA, 37 patients with systemic lupus erythematosus, 30 with osteoarthritis, 31 with gouty arthritis, and 80 healthy participants). Anti-cyclic citrullinated peptide (Anti-CCP) and anti-RA33 antibodies (Anti-RA33) were analyzed by ELISA. RF was detected by transmission immunoturbidimetry. Mann-Whitney U tests and Kruskal-Wallis tests compared differences among groups. Spearman's rank correlation analysis determined the relationship between biomarkers. Receiver-operator characteristic (ROC) curves were generated, and diagnostic performance was assessed by area under the curve (AUC), as well as specificity, sensitivity, likelihood ratios (LR).

Results

Median serum PCT concentrations were significantly higher (p < 0.0001) in patients with early RA (0.065 ng/ml) when compared with healthy controls (0.024 ng/ml), and patients with osteoarthritis (0.025 ng/ml). When compared with gouty arthritis (GA) controls (0.072 ng/ml) and systemic lupus erythematosus (SLE) controls (0.093 ng/ml), median serum PCT concentrations were not significant in patients with early RA (0.065 ng/ml). Median serum CT concentrations were significantly lower (p < 0.0001) in patients with early RA (0.880 pg/ml) compared with healthy controls (3.159 pg/ml), patients with SLE (2.480 pg/ml), and patients with GA (2.550 pg/ml). When compared with osteoarthritis controls (0.586 pg/ml), median serum CT concentrations were not significant in patients with early RA (0.880 pg/ml). ROC curve analysis comparing early RA with healthy controls demonstrated that the AUC of RF, anti-CCP, and anti-RA33 were 0.66, 0.73, and 0.64, respectively; the additions of PCT and CT further improved the diagnostic ability of early RA with the AUC of 0.97, 0.98, and 0.97, respectively (p < 0.01). The sensitivities of RF, anti-CCP, and anti-RA33 for early RA were 33.33%, 44.74%, and 58.33%, respectively, and the additions of PCT and CT showed very high sensitivities of 83.33%, 92.11%, and 87.50%. The high-value groups of PCT moderately correlated with the anti-RA33 levels (r = 0.417, p < 0.05). CT had no significant correlation with disease duration, radiographic progression, or clinical/serological variables, such as ESR levels, CRP levels, RF, anti-CCP, and anti-RA33 levels in early RA.

Conclusions

Serum PCT and CT combined with clinically available RA-related biomarkers could further improve the diagnostic efficiency of early RA.

New classification criteria for systemic lupus erythematosus

PURPOSE OF REVIEW

To compare the recently published European League Against Rheumatism (EULAR)/American College of Rheumatology (ACR) classification criteria for SLE with the Systemic Lupus International Collaborating Centers (SLICC) criteria and the earlier ACR criteria, focusing on their key concepts.

RECENT FINDINGS

Although the SLICC criteria introduced numbers of new criteria items, the new EULAR/ACR criteria added only noninfectious fever, based on an early SLE cohort study and an SLE patient survey, and condensed hematological, mucocutaneous and neurological items. Whereas the SLICC criteria maintained the overall structure familiar from the ACR criteria, the EULAR /ACR criteria use antinuclear antibodies (ANA) as an obligatory entry criterion, have weighted criteria and group these in domains. Where the SLICC criteria greatly increased sensitivity, losing some specificity, the EULAR/ACR criteria increased specificity again, for excellent classification criteria performance.

SUMMARY

Despite differences in structure and statistical performance, the EULAR/ACR and SLICC criteria agree on the importance of both immunological and clinical findings, on the high impact of lupus nephritis by histology, and on most clinical items.

Creation and Validation of Classification Criteria for Discoid Lupus Erythematosus

Importance

Classification criteria are the standardized definitions that are used to enroll uniform cohorts for research studies. They emphasize high specificity and are distinct from diagnostic criteria. No universally recognized classification criteria currently exist for discoid lupus erythematosus (DLE), which has led to problematic heterogeneity in observational and interventional clinical studies across the field.

Objective

To create and validate classification criteria for DLE using 12 previously defined candidate criteria items.

Design, Setting, and Participants

For this diagnostic study, candidate criteria items were prospectively applied by dermatologists and dermatopathologists at clinical visits of patients with DLE or a condition that could be confused for DLE, termed a DLE mimicker, at academic dermatology practices across the United States, Poland, Japan, and South Korea. Data were collected from December 1, 2017, to February 1, 2019, and analyzed from March 1 to September 19, 2019.

Main Outcomes and Measures

Clinical features among these 2 groups were calculated and compared with χ2 or Fisher exact tests. Candidate models were identified using best subsets logistic regression analysis. Improvement tests, fit statistics, and discrimination were considered to choose a final model.

Results

Nine sites contributed 215 patients, 15 of whom had missing or incomplete data. The final model for DLE classification criteria includes only clinical variables: atrophic scarring (3 points), location in the conchal bowl (2 points), preference for the head and neck (2 points), dyspigmentation (1 point), follicular hyperkeratosis and/or plugging (1 point), and erythematous to violaceous in color (1 point), with an area under the receiving operating characteristic curve of 0.91 (95% CI, 0.87-0.95). A score of at least 5 points yields a sensitivity of 84.1% and a specificity of 75.9% in the classification of DLE, with increasing scores yielding higher specificity.

Conclusions and Relevance

These findings provide the initial validation of classification criteria for DLE for use in observational and clinical trials.

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.

Performance of 2019 EULAR/ACR classification criteria for systemic lupus erythematosus in a paediatric population—a multicentre study

Objectives

The European League Against Rheumatism and American College of Rheumatology 2019 (EULAR/ACR-19) criteria for the diagnosis of SLE were recently published, with the stated goal of maintaining the level of sensitivity and raising the level of specificity for classification of SLE in adults. The aim of this study is to examine their application to juvenile SLE (jSLE) patients.

Methods

In this multicentre study the charts of jSLE patients from three tertiary medical centres were reviewed and compared with patients with non-jSLE diagnosis. Paediatric rheumatologists, blinded to the original diagnosis, reviewed and diagnosed all cases. Paediatric patients' clinical and laboratory data were retrospectively extracted and then examined with regard to how they met the new and old criteria.

Results

Included were 225 patients (112 jSLE, 113 non-SLE). When applied to juvenile SLE classification, the sensitivity of the new EULAR/ACR-19 criteria was 0.96 (95% CI: 0.9, 0.99) and the specificity was 0.89 (95% CI: 0.82, 0.94). These were comparable to the SLICC criteria. The sensitivity of the EULAR/ACR-19 criteria improves over time and was 0.83 12 months following disease onset, reaching 0.96 after longer than 24 months.

Conclusion

Among a cohort of jSLE patients, sensitivity of the new EULAR/ACR-19 criteria was found to be high and specificity may have improved slightly compared with the SLICC-12 criteria. We support the use of the new classification criteria for paediatric patients in future jSLE studies, but it should be noted that its specificity is lower than for adults.

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.

Development of a New International Antiphospholipid Syndrome Classification Criteria Phase I/II Report: Generation and Reduction of Candidate Criteria

OBJECTIVE

An international multidisciplinary initiative, jointly supported by the American College of Rheumatology and European Alliance of Associations for Rheumatology, is underway to develop new rigorous classification criteria to identify patients with high likelihood of antiphospholipid syndrome (APS) for research purposes. The present study was undertaken to apply an evidence- and consensus-based approach to identify candidate criteria and develop a hierarchical organization of criteria within domains.

METHODS

During phase I, the APS classification criteria steering committee used systematic literature reviews and surveys of international APS physician scientists to generate a comprehensive list of items related to APS. In phase II, we reviewed the literature, administered surveys, formed domain subcommittees, and used Delphi exercises and nominal group technique to reduce potential APS candidate criteria. Candidate criteria were hierarchically organized into clinical and laboratory domains.

RESULTS

Phase I generated 152 candidate criteria, expanded to 261 items with the addition of subgroups and candidate criteria with potential negative weights. Using iterative item reduction techniques in phase II, we initially reduced these items to 64 potential candidate criteria organized into 10 clinical and laboratory domains. Subsequent item reduction methods resulted in 27 candidate criteria, hierarchically organized into 6 additive domains (laboratory, macrovascular, microvascular, obstetric, cardiac, and hematologic) for APS classification.

CONCLUSION

Using data- and consensus-driven methodology, we identified 27 APS candidate criteria in 6 clinical or laboratory domains. In the next phase, the proposed candidate criteria will be used for real-world case collection and further refined, organized, and weighted to determine an aggregate score and threshold for APS classification.

Towards classification criteria for early-stage knee osteoarthritis: A population-based study to enrich for progressors

OBJECTIVE

To facilitate a greater likelihood of favorable response to new disease-modifying therapies, recruitment of patients at an earlier stage of their disease into clinical trials may be an attractive strategy. Hence, there is a need to develop widely accepted classification criteria for early-stage knee osteoarthritis (OA). We have proposed a set of classification criteria for early-stage knee OA (2018 classification criteria) now being further refined. Here, we test the draft criteria for enrichment for clinical and structural progression.

DESIGN

Performance of the 2018 classification criteria for early stage knee OA was tested using data from the Osteoarthritis Initiative (OAI). The OAI comprises data of 4796 men and women aged 45-79 years with or at risk for knee OA at baseline. Based on the 2018 classification criteria, a knee with Kellgren & Lawrence (K&L) grade of 0-I, two out of four Knee Injury and Osteoarthritis Outcome Score (KOOS) subscales equal or less than 85, and presence of at least one of joint line tenderness or crepitus, was considered as early-stage knee OA. Knees with K&L grade 0-I that did not fulfill the 2018 criteria, were considered as controls. Logistic regression analysis was used to evaluate the predictive performance of the criteria set for structural as well as clinical progression. We further explored the discriminatory capability of criteria by including the average KOOS₄ score, and relevant clinical examination findings such as the presence of effusion and/or Heberden's nodes.

RESULTS

We identified 1315 (27%) knees from OAI fulfilling the 2018 early-stage knee OA classification criteria. The female to male ratio was higher in the early knee OA group compared to controls. The early-stage knee OA group were on average slightly younger and had higher body mass index vs controls (mean [SD] age: 59.2 [8.9] years vs. 60.2 [9.1] and mean [SD] BMI 28.3 [7.0] vs. 26.8 [6.0]). By applying the 2018 criteria, there was a substantial enrichment compared to controls at 48 and 96 months for both structural (OR=1.1-1.4, and AUC=0.72-0.74) and clinical progressors (OR=2.1-2.5, 95% and AUC=0.66). Expanding the clinical examination findings by including joint effusion and/or Heberden's nodes improved the enrichment for both structural and clinical progressors (OR=4.2, 95% confidence interval=3.2-5.5 and OR=3.3, 95% confidence interval=2.8-3.5, respectively). Replacing scoring of the 4 separate KOOS domains by a KOOS₄ score performed comparably.

CONCLUSIONS

The proposed 2018 early-stage knee OA classification criteria showed encouraging performance characteristics with regard to an enrichment for structural and clinical progression using longitudinal OAI data. Our results indicate that the addition of clinical findings improves the performance of previous criteria to define early-stage disease and risk for progression.

Performance of the 2019 EULAR/ACR classification criteria for systemic lupus erythematosus in early disease, across sexes and ethnicities

OBJECTIVES

The European League Against Rheumatism (EULAR)/American College of Rheumatology (ACR) 2019 Classification Criteria for systemic lupus erythematosus (SLE) have been validated with high sensitivity and specificity. We evaluated the performance of the new criteria with regard to disease duration, sex and race/ethnicity, and compared its performance against the Systemic Lupus International Collaborating Clinics (SLICC) 2012 and ACR 1982/1997 criteria.

METHODS

Twenty-one SLE centres from 16 countries submitted SLE cases and mimicking controls to form the validation cohort. The sensitivity and specificity of the EULAR/ACR 2019, SLICC 2012 and ACR 1982/1997 criteria were evaluated.

RESULTS

The cohort consisted of female (n=1098), male (n=172), Asian (n=118), black (n=68), Hispanic (n=124) and white (n=941) patients; with an SLE duration of 1 to <3 years (n=196) and ≥5 years (n=879). Among patients with 1 to <3 years disease duration, the EULAR/ACR criteria had better sensitivity than the ACR criteria (97% vs 81%). The EULAR/ACR criteria performed well in men (sensitivity 93%, specificity 96%) and women (sensitivity 97%, specificity 94%). Among women, the EULAR/ACR criteria had better sensitivity than the ACR criteria (97% vs 83%) and better specificity than the SLICC criteria (94% vs 82%). Among white patients, the EULAR/ACR criteria had better sensitivity than the ACR criteria (95% vs 83%) and better specificity than the SLICC criteria (94% vs 83%). The EULAR/ACR criteria performed well among black patients (sensitivity of 98%, specificity 100%), and had better sensitivity than the ACR criteria among Hispanic patients (100% vs 86%) and Asian patients (97% vs 77%).

CONCLUSIONS

The EULAR/ACR 2019 criteria perform well among patients with early disease, men, women, white, black, Hispanic and Asian patients. These criteria have superior sensitivity than the ACR criteria and/or superior specificity than the SLICC criteria across many subgroups.

Neue Klassifikationskriterien des SLE: was helfen sie für die klinische Diagnose des SLE?

Im September 2019 sind die gemeinsamen Klassifikationskriterien der European League Against Rheumatism (EULAR) und des American College of Rheumatology (ACR) für den systemischen Lupus erythematodes (SLE) erschienen. Die EULAR/ACR 2019 Klassifikationskriterien verwenden (jemals) positive antinukleäre Antikörper (ANA) als obligates Eingangskriterium und gewichtete Kriterien mit Werten von 2 bis 10 und einem Cut-off von 10. Die Kriterien sind in 10 Domänen geordnet, innerhalb derer Assoziationen zwischen verschiedenen Manifestationen bestehen, und nur der höchste Wert in einer Domäne wird verwendet. Kriterien werden nur gewertet, wenn es für sie keine andere Erklärung gibt, die wahrscheinlicher ist als der SLE. Die neuen Kriterien sind statistisch den älteren Kriteriensets überlegen. Sie gelten aber nur für die Klassifikation. Für die meisten Rheumatologinnen und Rheumatologen ist das Stellen der Diagnose eines SLE wesentlich relevanter als der Einschluss in SLE-Studien, für den die Klassifikationskriterien gedacht sind. Daher stellt sich die Frage, wie weit die Klassifikationskriterien für die Diagnose helfen können. Direkt dafür verwendet werden dürfen sie wirklich nicht. Erfahrene Ärztinnen und Ärzte sind besser und v. a. sensitiver als die besten Kriterien. Manche Detailinformationen helfen aber dennoch dabei, die individuelle Diagnose für konkret Patientinnen und Patienten zu stellen. Die vorliegende Arbeit erörtert die Neuigkeiten in den EULAR/ACR 2019-Kriterien, stellt den Unterschied zwischen Klassifikation und Diagnose dar und diskutiert, welche Informationen auch im klinischen Alltag Anwendung finden können.

New Criteria for Lupus

Purpose of the Review

Classification criteria define the patient population for clinical trials and translational studies, but also influence current understanding of the disease. This review attempts to delineate the development from the American College of Rheumatology (ACR) 1982 to the European League Against Rheumatism (EULAR)/ACR 2019 classification criteria for systemic lupus erythematosus (SLE).

Recent Findings

The new EULAR/ACR classification criteria use antinuclear antibodies (ANA) as an entry criterion. (Non-infectious) fever is the one new criterion. All criteria items now have individual weights (from 2 to 10) and are structured in domains, within which only the highest item is counted. There is one common attribution rule, counting criteria only if there is no more likely alternative explanation. Ten points are sufficient for classification. The new criteria have reached a sensitivity of 96.1% and a specificity of 93.4%.

Summary

The new EULAR/ACR 2019 classification criteria for SLE build on the previous criteria sets, adding fever only as a new criteria item. The new structure is reflective of the current diagnostic approach and has led to improved statistical performance.

The 2019 American College of Rheumatology/European League Against Rheumatism classification criteria for IgG4-related disease

IgG4-related disease (IgG4-RD) can cause fibroinflammatory lesions in nearly any organ. Correlation among clinical, serological, radiological and pathological data is required for diagnosis. This work was undertaken to develop and validate an international set of classification criteria for IgG4-RD. An international multispecialty group of 86 physicians was assembled by the American College of Rheumatology (ACR) and the European League Against Rheumatism (EULAR). Investigators used consensus exercises; existing literature; derivation and validation cohorts of 1879 subjects (1086 cases, 793 mimickers); and multicriterion decision analysis to identify, weight and test potential classification criteria. Two independent validation cohorts were included. A three-step classification process was developed. First, it must be demonstrated that a potential IgG4-RD case has involvement of at least one of 11 possible organs in a manner consistent with IgG4-RD. Second, exclusion criteria consisting of a total of 32 clinical, serological, radiological and pathological items must be applied; the presence of any of these criteria eliminates the patient from IgG4-RD classification. Third, eight weighted inclusion criteria domains, addressing clinical findings, serological results, radiological assessments and pathological interpretations, are applied. In the first validation cohort, a threshold of 20 points had a specificity of 99.2% (95% CI 97.2% to 99.8%) and a sensitivity of 85.5% (95% CI 81.9% to 88.5%). In the second, the specificity was 97.8% (95% CI 93.7% to 99.2%) and the sensitivity was 82.0% (95% CI 77.0% to 86.1%). The criteria were shown to have robust test characteristics over a wide range of thresholds. ACR/EULAR classification criteria for IgG4-RD have been developed and validated in a large cohort of patients. These criteria demonstrate excellent test performance and should contribute substantially to future clinical, epidemiological and basic science investigations.

2019 European League Against Rheumatism/American College of Rheumatology Classification Criteria for Systemic Lupus Erythematosus

OBJECTIVE

To develop new classification criteria for systemic lupus erythematosus (SLE) jointly supported by the European League Against Rheumatism (EULAR) and the American College of Rheumatology (ACR).

METHODS

This international initiative had four phases. 1) Evaluation of antinuclear antibody (ANA) as an entry criterion through systematic review and meta-regression of the literature and criteria generation through an international Delphi exercise, an early patient cohort, and a patient survey. 2) Criteria reduction by Delphi and nominal group technique exercises. 3) Criteria definition and weighting based on criterion performance and on results of a multi-criteria decision analysis. 4) Refinement of weights and threshold scores in a new derivation cohort of 1,001 subjects and validation compared with previous criteria in a new validation cohort of 1,270 subjects.

RESULTS

The 2019 EULAR/ACR classification criteria for SLE include positive ANA at least once as obligatory entry criterion; followed by additive weighted criteria grouped in 7 clinical (constitutional, hematologic, neuropsychiatric, mucocutaneous, serosal, musculoskeletal, renal) and 3 immunologic (antiphospholipid antibodies, complement proteins, SLE-specific antibodies) domains, and weighted from 2 to 10. Patients accumulating ≥10 points are classified. In the validation cohort, the new criteria had a sensitivity of 96.1% and specificity of 93.4%, compared with 82.8% sensitivity and 93.4% specificity of the ACR 1997 and 96.7% sensitivity and 83.7% specificity of the Systemic Lupus International Collaborating Clinics 2012 criteria.

CONCLUSION

These new classification criteria were developed using rigorous methodology with multidisciplinary and international input, and have excellent sensitivity and specificity. Use of ANA entry criterion, hierarchically clustered, and weighted criteria reflects current thinking about SLE and provides an improved foundation for SLE research.

2019 European League Against Rheumatism/American College of Rheumatology classification criteria for systemic lupus erythematosus

OBJECTIVE

To develop new classification criteria for systemic lupus erythematosus (SLE) jointly supported by the European League Against Rheumatism (EULAR) and the American College of Rheumatology (ACR).

METHODS

This international initiative had four phases. (1) Evaluation of antinuclear antibody (ANA) as an entry criterion through systematic review and meta-regression of the literature and criteria generation through an international Delphi exercise, an early patient cohort and a patient survey. (2) Criteria reduction by Delphi and nominal group technique exercises. (3) Criteria definition and weighting based on criterion performance and on results of a multi-criteria decision analysis. (4) Refinement of weights and threshold scores in a new derivation cohort of 1001 subjects and validation compared with previous criteria in a new validation cohort of 1270 subjects.

RESULTS

The 2019 EULAR/ACR classification criteria for SLE include positive ANA at least once as obligatory entry criterion; followed by additive weighted criteria grouped in seven clinical (constitutional, haematological, neuropsychiatric, mucocutaneous, serosal, musculoskeletal, renal) and three immunological (antiphospholipid antibodies, complement proteins, SLE-specific antibodies) domains, and weighted from 2 to 10. Patients accumulating ≥10 points are classified. In the validation cohort, the new criteria had a sensitivity of 96.1% and specificity of 93.4%, compared with 82.8% sensitivity and 93.4% specificity of the ACR 1997 and 96.7% sensitivity and 83.7% specificity of the Systemic Lupus International Collaborating Clinics 2012 criteria.

CONCLUSION

These new classification criteria were developed using rigorous methodology with multidisciplinary and international input, and have excellent sensitivity and specificity. Use of ANA entry criterion, hierarchically clustered and weighted criteria reflect current thinking about SLE and provide an improved foundation for SLE research.

Multicriteria decision analysis process to develop new classification criteria for systemic lupus erythematosus

European League Against Rheumatism and are jointly supporting multiphase development of systemic lupus erythematosus (SLE) classification criteria based on weighted criteria and a continuous probability scale. Prior steps included item generation, item reduction and hierarchical organisation of candidate criteria using an evidence-based approach. Our objectives were to determine relative weights using multicriteria decision analysis (MCDA) and to set a provisional threshold score for SLE classification. An SLE Expert Panel (8 European, 9 North American) submitted 164 real, unique cases with a wide range of SLE probability in a standardised format. Using the candidate criteria, experts scored and rank-ordered 20 representative cases. At an in-person meeting, experts reviewed inter-rater reliability of scoring, further refined criteria definitions and participated in an MCDA exercise. Based on expert consensus decisions on pairwise comparisons of criteria, 1000minds software calculated criteria weights and rank-ordered the remaining 144 cases based on their additive scores. The score of the lowest-ranked case for which complete expert consensus was achieved defined the provisional threshold classification score. Inter-rater reliability of scoring cases with the candidate criteria was good. MCDA involved 74 pairwise decisions and was repeated for the arthritis and mucocutaneous domains when the initial ranking of some cases did not match expert opinion. After criteria weights and additive scores were recalculated once, experts reached consensus for SLE classification for all cases scoring>83. Using an iterative process, the candidate criteria definitions were refined, preliminary weights were calculated and a provisional threshold score for SLE classification was determined.

Agreement of three commercial anti-extractable nuclear antigen tests: EUROASSAY Anti-ENA Profile, Polycheck Autoimmune Test and FIDIS Connective Profile

Background Detection of antibodies to extractable nuclear antigens (ENAs) is needed for the diagnosis in systemic autoimmune diseases. In this study, we compared three reagents using line immunoblot assay (LIA) or multiplex bead immunoassay for detecting the anti-ENAs. Methods A total of 89 sera were tested by 3 different assays: EUROASSAY Anti-ENA Profile (Euroimmune, Germany), Polycheck Autoimmune Test (Biocheck GmbH, Germany), and FIDIS™ Connective Profile (Biomedical Diagnostics, France). The following individual ENAs were investigated: Sm, SS-A (Ro), SS-B (La), Scl-70, Jo-1 and RNP. We reviewed medical records to investigate the discrepant results among three methods. Results Overall percent agreements were 96.1% between EUROASSAY Anti-ENA Profile and FIDIS™ Connective profile; 90.4% between EUROASSAY Anti-ENA Profile and Polycheck Autoimmune Test using the manufacturers’ cutoff; 96.4% between EUROASSAY Anti-ENA Profile and Polycheck Autoimmune Test using a upward cutoff; 90.4% between FIDIS™ Connective profile and Polycheck Autoimmune Test the manufacturers’ cutoff; and 96.4% between FIDIS™ Connective profile and Polycheck Autoimmune Test a upward cutoff. Conclusions The three assays showed excellent agreement with each other. With appropriate cutoff, the all three assays for six of the anti-ENA tests investigated in this study can be used in clinical laboratories for detecting the anti-ENAs.

Use of Consensus Methodology to Determine Candidate Items for Systemic Lupus Erythematosus Classification Criteria

Objective.

Given the complexity and heterogeneity of systemic lupus erythematosus (SLE), high-performing classification criteria are critical to advancing research and clinical care. A collaborative effort by the European League Against Rheumatism and the American College of Rheumatology was undertaken to generate candidate criteria, and then to reduce them to a smaller set. The objective of the current study was to select a set of criteria that maximizes the likelihood of accurate classification of SLE, particularly early disease.

Methods.

An independent panel of international SLE experts and the SLE classification criteria steering committee (conducting SLE research in Canada, Mexico, United States, Austria, Germany, Greece, France, Italy, and Spain) ranked 43 candidate criteria. A consensus meeting using nominal group technique (NGT) was conducted to reduce the list of criteria for consideration.

Results.

The expert panel NGT exercise reduced the candidate criteria for SLE classification from 43 to 21. The panel distinguished potential “entry criteria,” which would be required for classification, from potential “additive criteria.” Potential entry criteria were antinuclear antibody (ANA) ≥ 1:80 (HEp-2 immunofluorescence), and low C3 and/or low C4. The use of low complement as an entry criterion was considered potentially useful in cases with negative ANA. Potential additive criteria included lupus nephritis by renal biopsy, autoantibodies, cytopenias, acute and chronic cutaneous lupus, alopecia, arthritis, serositis, oral mucosal lesions, central nervous system manifestations, and fever.

Conclusion.

The NGT exercise resulted in 21 candidate SLE classification criteria. The next phases of SLE classification criteria development will require refinement of criteria definitions, evaluation of the ability to cluster criteria into domains, and evaluation of weighting of criteria.

Applied Bayesian Methods in the Rheumatic Diseases

The use of applied Bayesian methods is increasing in rheumatology. Using the Bayes theorem, past evidence is updated with new data. Preexisting data are expressed as a prior probability distribution or prior. New observations are expressed as a likelihood. Through explicit incorporation of preexisting data and new data, this process informs how this new information should change the way we think. In this article, the authors highlight the use of applied Bayesian methods in the study of rheumatic diseases.

Epidemiology and Survival of Systemic Sclerosis-Systemic Lupus Erythematosus Overlap Syndrome

OBJECTIVE

Systemic sclerosis (SSc) may overlap with systemic lupus erythematous (SLE). Little is known about the epidemiology, clinical characteristics, and survival of SSc-SLE overlap. We evaluated the prevalence of SSc-SLE overlap and differences in SSc characteristics, and compared survival with SSc without SLE.

METHODS

A cohort study was conducted including subjects who fulfilled the American College of Rheumatology (ACR)/European League Against Rheumatism classification criteria for SSc and/or the ACR criteria for SLE. The primary outcome was time from diagnosis to all-cause mortality. Survival was evaluated using Kaplan-Meier and Cox proportional hazard models.

RESULTS

We identified 1252 subjects (SSc: n = 1166, SSc-SLE: n = 86) with an SSc-SLE prevalence of 6.8%. Those with SSc-SLE were younger at diagnosis (37.9 yrs vs 47.9 yrs, p < 0.001), more frequently East Asian (5.5% vs 20%) or South Asian (5.1% vs 12%), had lupus anticoagulant (6% vs 0.3%, p < 0.001), anticardiolipin antibody (6% vs 0.9%, p < 0.001), and pulmonary arterial hypertension (PAH; 52% vs 31%, p < 0.001). Those with SSc-SLE less frequently had calcinosis (13% vs 27%, p = 0.007), telangiectasia (49% vs 75%, p < 0.001), and diffuse subtype (12% vs 35%, p < 0.001). There were no significant differences in the occurrence of renal crisis (7% vs 7%), interstitial lung disease (ILD; 41% vs 34%), and digital ulcers (38% vs 32%). Those with SSc-SLE had better median survival time (26.1 vs 22.4 yrs), but this was not statistically significant (log-rank p = 0.06). Female sex and diffuse subtype attenuated survival differences between groups (HR 1.07, 95% CI 0.67-1.67).

CONCLUSION

Patients with SSc-SLE are younger at diagnosis, more frequently have PAH, and less frequently have cutaneous manifestations of SSc. They should be monitored for ILD, renal crisis, and digital ulcers.

Clinical classification criteria for neurogenic claudication caused by lumbar spinal stenosis. The N-CLASS criteria

BACKGROUND CONTEXT

Because imaging findings of lumbar spinal stenosis (LSS) may not be associated with symptoms, clinical classification criteria based on patient symptoms and physical examination findings are needed.

PURPOSE

The objective of this study was to develop clinical classification criteria that identify patients with neurogenic claudication (NC) caused by LSS.

STUDY DESIGN

This study is a two-stage process that includes Phase 1, the Delphi process, and Phase 2, the cross-sectional study.

PATIENT SAMPLE

Outpatients were recruited from spine clinics in five countries.

OUTCOME MEASURE

The outcome measure includes items from the patients' history and physical examination.

METHODS

In Phase 1, a list of potential predictors of NC caused by LSS was based on the available literature and was evaluated through a Delphi process involving 17 spine specialists (surgeons and non-surgeons) from eight countries. In Phase 2, 19 different clinical spine specialists from five countries identified patients they classified as having (1) NC caused by LSS, (2) radicular pain caused by lumbar disc herniation (LDH), or (3) non-specific low back pain (NSLBP) with radiating leg pain. The patients completed survey items and the specialists documented the examination signs. Coefficients from general estimating equation models were used to select predictors, to generate a clinical classification score, and to obtain a receiver operating characteristic curve. Conduction of the Delphi process, data management, and statistical analysis were partially supported by an unrestricted grant of less than 15,000 US dollars from Merck Sharp & Dohme. No fees were allocated to participating spine specialists.

RESULTS

Phase 1 generated a final list of 46 items related to LSS. In Phase 2, 209 patients with leg pain caused by LSS (n=63), LDH (n=89), or NSLBP (n=57) were included. Criteria that independently predicted NC (p<.05) were age over 60 years, positive 30-second extension test, negative straight leg test, pain in both legs, leg pain relieved by sitting, and leg pain decreased by leaning forward or flexing the spine. A classification score using a weighted set of these criteria was developed. The proposed N-CLASS score ranged from 0 to 19 and had an area under the curve of 0.92, and the cutoff (>10/19) to obtain a specificity of >90.0% resulted in a sensitivity of 82.0%.

CONCLUSIONS

Clinical criteria independently associated with neurogenic claudication due to LSS were identified. The use of these symptom and physical variables as a classification score for clinical research could improve homogeneity among enrolled patients.

Developing and Refining New Candidate Criteria for Systemic Lupus Erythematosus Classification: An International Collaboration

OBJECTIVE

To define candidate criteria within multiphase development of systemic lupus erythematosus (SLE) classification criteria, jointly supported by the American College of Rheumatology and the European League Against Rheumatism. Prior steps included item generation and reduction by Delphi exercise, further narrowed to 21 items in a nominal group technique exercise. Our objectives were to apply an evidence-based approach to the 21 candidate criteria, and to develop hierarchical organization of criteria within domains.

METHODS

A literature review identified the sensitivity and specificity of the 21 candidate criteria. Data on the performance of antinuclear antibody (ANA) as an entry criterion and operating characteristics of the candidate criteria in early SLE patients were evaluated. Candidate criteria were hierarchically organized into clinical and immunologic domains, and definitions were refined in an iterative process.

RESULTS

Based on the data, consensus was reached to use a positive ANA of ≥1:80 titer (HEp-2 cells immunofluorescence) as an entry criterion and to have 7 clinical and 3 immunologic domains, with hierarchical organization of criteria within domains. Definitions of the candidate criteria were specified.

CONCLUSION

Using a data-driven process, consensus was reached on new, refined criteria definitions and organization based on operating characteristics. This work will be followed by a multicriteria decision analysis exercise to weight criteria and to identify a threshold score for classification on a continuous probability scale.

New Myositis Classification Criteria-What We Have Learned Since Bohan and Peter

PURPOSE OF REVIEW

Idiopathic inflammatory myopathy (IIM) classification criteria have been a subject of debate for many decades. Despite several limitations, the Bohan and Peter criteria are still widely used. The aim of this review is to discuss the evolution of IIM classification criteria.

RECENT FINDINGS

New IIM classification criteria are periodically proposed. The discovery of myositis-specific and myositis-associated autoantibodies led to the development of clinico-serological criteria, while in-depth description of IIM morphological features improved histopathology-based criteria. The long-awaited European League Against Rheumatism and American College of Rheumatology (EULAR/ACR) IIM classification criteria were recently published. The Bohan and Peter criteria are outdated and validated classification criteria are necessary to improve research in IIM. The new EULAR/ACR IIM classification criteria are thus a definite improvement and an important step forward in the field.

Serum connective tissue growth factor is a highly discriminatory biomarker for the diagnosis of rheumatoid arthritis

BACKGROUND

Our previous proteomic study indicated that connective tissue growth factor (CTGF) may be a potential biomarker for rheumatoid arthritis (RA) diagnosis. The aim was to assess the performance of CTGF as a biomarker of RA.

METHOD

Serum and synovial fluid CTGF was detected using a direct high sensitivity sandwich ELISA kit. Serum CTGF levels were tested for discriminatory capacity and optimal assay cutoffs determined in a training cohort of 98 cases of RA with 103 healthy controls. The assay performance was then validated in a further cohort of 572 patients (with RA (n = 217), ankylosing spondylitis (n = 92), gout (n = 74), osteoarthritis (n = 52), systemic lupus erythematosus (n = 72), or primary Sjögren's syndrome (pSS) (n = 65)).

RESULTS

Significant elevation of synovial fluid CTGF concentration was found in RA patients, demonstrating excellent diagnostic ability to predict RA (area under the curve (AUC) = 0.97). Similar results were found in serum CTGF detection. At the optimal cutoff value 88.66 pg/mL, the sensitivity, specificity, and the AUC was 0.86, 0.92, and 0.92, respectively, in the training cohort. Similar performance was observed in the validation cohort, with sensitivity, specificity, positive likelihood, and negative likelihood of 0.82, 0.91, 5.74, and 0.12, respectively. Stronger discriminatory capacity was seen with the combination of CTGF and anti-citrullinated protein antibody (ACPA) (AUC = 0.96) than with either ACPA or rheumatoid factor (RF) alone (AUC = 0.80 or 0.79, respectively). The discriminatory performance of serum CTGF was consistent across all inflammatory conditions tested (AUC >0.92 in all cases), with the sole exception of pSS. Serum CTGF did not vary with symptom duration or disease activity.

CONCLUSIONS

Serum CTGF is a promising diagnostic biomarker for RA, with performance in the current study better than either ACPA or RF.

Undifferentiated connective tissue diseases and adverse pregnancy outcomes. An undervalued association?

Undifferentiated connective tissue diseases (UCTDs) are a heterogeneous group of disorders characterized by symptoms and signs suggestive of systemic autoimmune rheumatic disease (ARD), but which do not fulfill all the established criteria for definite diagnosis of a condition. Although a third of UCTDs can progress to a definite ARD within months or years, most UCTDs can remain stable for years with minimal disease activity. The annual incidence of UCTD in the general population ranges from 14 to 140 per 100 000 people. UCTDs are associated with the persistence of several circulating autoantibodies including antinuclear, antiphospholipid or antithyroid antibodies. Immunological evaluation of subjects with UCTDs suggests a proinflammatory state and dysregulation of the Th1/Th2 balance. Autoantibodies have well-known deleterious effects on placentation and have been associated with an increased risk of prematurity, fetal growth restriction (FGR), preeclampsia, and congenital atrioventricular heart block. Although epidemiological and biological data suggest a potential negative impact on reproductive outcomes, the relationship between UCTD and pregnancy outcomes has not been adequately studied. While awaiting definitive data from large studies, obstetricians should be aware that rheumatic disorders in their early, incomplete, or undifferentiated phases can adversely affect pregnancy outcomes, increasing the likelihood of pregnancy loss, FGR, preeclampsia, and prematurity.