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-ß2-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 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.

Clinical phenotypes of IgG4-related disease: an analysis of two international cross-sectional cohorts.

OBJECTIVE: IgG4-related disease (IgG4-RD) is a heterogeneous, multiorgan condition of unclear aetiology that can cause organ failure. Difficulty recognising IgG4-RD contributes to diagnostic delays. We sought to identify key IgG4-RD phenotypes. METHODS: We used two cross-sectional studies assembled by an international, multispecialty network of IgG4-RD specialists who submitted 765 cases to derive and replicate phenotypic groups. Phenotype groups of disease manifestations and key covariate distributions across the identified groups were measured using latent class analysis. RESULTS: In the derivation cohort (n=493), we identified four groups with distinct manifestations: Group 1 (31%), Pancreato-Hepato-Biliary disease; Group 2 (24%), Retroperitoneal Fibrosis and/or Aortitis; Group 3 (24%), Head and Neck-Limited disease and Group 4 (22%), classic Mikulicz syndrome with systemic involvement. We replicated the identification of four phenotype groups in the replication cohort. Compared with cases in Groups 1, 2 and 4, respectively, cases in Group 3 were more likely to be female (OR 11.60 (95% CI 5.39 to 24.98), 10.35 (95% CI 4.63 to 23.15) and 9.24 (95% CI 3.53 to 24.20)) and Asian (OR 6.68 (95% CI 2.82 to 15.79), 7.43 (95% CI 2.97 to 18.56) and 6.27 (95% CI 2.27 to 17.29)). Cases in Group 4 had a higher median serum IgG4 concentration (1170 mg/dL) compared with groups 1-3 (316, 178 and 445 mg/dL, respectively, p<0.001). CONCLUSION: We identified four distinctive IgG4-RD phenotypes according to organ involvement. Being Asian or female may predispose individuals to head and neck-limited disease. These phenotypes serve as a framework for identifying IgG4-RD and studying its aetiology and optimal treatment.

Development of a Glucocorticoid Toxicity Index (GTI) using multicriteria decision analysis.

OBJECTIVES: To develop a Glucocorticoid Toxicity Index (GTI) to assess glucocorticoid (GC)-related morbidity and GC-sparing ability of other therapies. METHODS: Nineteen experts on GC use and outcome measures from 11 subspecialties participated. Ten experts were from the USA; nine from Canada, Europe or Australia. Group consensus methods and multicriteria decision analysis (MCDA) were used. A Composite GTI and Specific List comprise the overall GTI. The Composite GTI reflects toxicity likely to change during a clinical trial. The Composite GTI toxicities occur commonly, vary with GC exposure, and are weighted and scored. Relative weights for items in the Composite GTI were derived by group consensus and MCDA. The Specific List is designed to capture GC toxicity not included in the Composite GTI. The Composite GTI was evaluated by application to paper cases by the investigators and an external group of 17 subspecialists. RESULTS: Thirty-one toxicity items were included in the Composite GTI and 23 in the Specific List. Composite GTI evaluation showed high inter-rater agreement (investigators κ 0.88, external raters κ 0.90). To assess the degree to which the Composite GTI corresponds to expert clinical judgement, participants ranked 15 cases by clinical judgement in order of highest to lowest GC toxicity. Expert rankings were then compared with case ranking by the Composite GTI, yielding excellent agreement (investigators weighted κ 0.87, external raters weighted κ 0.77). CONCLUSIONS: We describe the development and initial evaluation of a comprehensive instrument for the assessment of GC toxicity.

Development of a Multidimensional Additive Points System for Determining Access to Rheumatology Services.

OBJECTIVE: In many countries, including New Zealand, the demand for rheumatology services exceeds their supply, resulting in some patients experiencing long delays or being denied access. The principal aim of this work was to create a validated, transparent, and fair system for determining access to rheumatology services. METHODS: A panel of 5 rheumatologists, 6 primary care physicians, and 4 nurse specialists ranked a series of 25 clinical scenarios in order of priority to see a rheumatologist. Important determining factors were weighted in an iterative process to generate a multidimensional additive point score to determine access to rheumatology service. RESULTS: The score comprises 6 domains of 2 to 4 items weighted to give a total score out of 100. The effect of the problem on the patient's life and role, the presence of an inflammatory rheumatic disease, appropriateness of current treatment, and the ability of the rheumatologist to influence the current symptoms and future prognosis were felt to be critical factors in determining access to the service. The score showed a strong correlation with the rankings agreed by the clinical panel, and the overall intraclass correlation coefficient for the rheumatologists was 0.698. CONCLUSIONS: Our score has face validity, is easy to perform, and has been assessed by an independent panel of rheumatologists as providing a fair system for determining access to rheumatology services. The system is acceptable to primary care physicians and has been adopted by our local primary care organizations.

Classification Criteria for Axial Disease in Youth with Juvenile Spondyloarthritis.

OBJECTIVES: To develop and validate classification criteria for axial disease in youth with juvenile spondyloarthritis (SpA; AxJSpA). METHODS: This international initiative consisted of four phases: 1) Item generation; 2) Item reduction; 3) Criteria development; and 4) Validation of the AxJSpA criteria by an independent team of experts in an internationally representative Validation cohort. RESULTS: These criteria are intended to be used on youth with a physician diagnosis of juvenile SpA and for whom axial disease is suspected. Item generation consisted of a systematic literature review and a free-listing exercise using input from international physicians and collectively resulted in 108 items. After the item reduction exercise and expert panel input, 37 items remained for further consideration. The final AxJSpA criteria domains included: imaging: active inflammation, imaging: structural lesions, pain chronicity, pain pattern, pain location, stiffness, and genetics. The most heavily weighted domains were active inflammation and structural lesions on imaging. Imaging typical of sacroiliitis was deemed necessary, but not sufficient, to classify a youth with AxJSpA. The threshold for classification of AxJSpA was a score of ≥55 (out of 100). When tested in the validation data set, the final criteria had a specificity of 97.5% (95% CI: 91.4-99.7), sensitivity of 64.3% (95% CI: 54.9-73.1) and Area Under the Receiver Operating Characteristic (AUROC) curve of 0.81 (95% CI: 0.76-0.86). CONCLUSIONS: The new AxJSpA classification criteria require an entry criterion, physician diagnosis of juvenile SpA, and include seven weighted domains. The AxJSpA classification criteria are validated and designed to identify participants for research studies.

Development of the 2023 ACR/EULAR Antiphospholipid Syndrome Classification Criteria, Phase III-D Report: Multi Criteria Decision Analysis.

BACKGROUND: The 2023 ACR/EULAR Antiphospholipid Syndrome (APS) Classification Criteria development, aiming to identify patients with high likelihood of APS for research, employed a four-phase methodology. Phase I and II resulted in 27 proposed candidate criteria, organized into laboratory and clinical domains. Here, we summarize the last stage of Phase III efforts employing a consensus-based multi-criteria decision analysis (MCDA) to weigh candidate criteria and identify an APS classification threshold score. METHODS: We evaluated 192 unique, international real-world cases referred for "suspected APS" with a wide range of APS manifestations. Using proposed candidate criteria, subcommittee members rank-ordered 20 representative cases from highly unlikely to highly likely APS. During an in-person meeting, the subcommittee refined definitions and participated in an MCDA exercise to identify relative weights of candidate criteria. Using consensus decisions and pairwise criteria comparisons, 1000Minds™ software assigned criteria weights, and we rank ordered 192 cases by their additive scores. A consensus-based threshold score for APS classification was set. RESULTS: Pre-meeting evaluation of 20 representative cases demonstrated variability in APS assessment. MCDA resolved 81 pairwise decisions; relative weights identified domain item hierarchy. After assessing 192 cases by weights and additive scores, the Steering Committee reached consensus that APS classification should require separate clinical and laboratory scores, rather than a single aggregate score, to ensure high specificity. CONCLUSION: Using MCDA, candidate criteria preliminary weights were determined. Unlike other disease classification systems using a single aggregate threshold score, separate clinical and laboratory domain thresholds were incorporated into the new APS classification criteria.

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-ß2 -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.

The pediatric glucocorticoid toxicity index.

OBJECTIVES: To develop a Pediatric glucocorticoid toxicity index (pGTI), a standardized, weighted clinical outcome assessment that measures change in glucocorticoid (GC) toxicity over time. METHODS: Fourteen physician experts from 7 subspecialties participated. The physician experts represented multiple subspecialties in which GCs play a major role in the treatment of inflammatory disease: nephrology, rheumatology, oncology, endocrinology, genetics, psychiatry, and maternal-fetal medicine. Nine investigators were from Canada, Europe, or New Zealand, and 5 were from the United States. Group consensus methods and multi-criteria decision analysis were used. The pGTI is an aggregate assessment of GC toxicities that are common, important, and dynamic. These toxicities are organized into health domains graded as minor, moderate, or major and are weighted according to severity. The relative weights were derived by group consensus and multi-criteria decision analysis using the 1000MindsTM software platform. Two quantitative scores comprise the overall toxicity profile derived from pGTI data: (1) the Cumulative Worsening Score; and (2) the Aggregate Improvement Score. The pGTI also includes a qualitative, unweighted record of GC side-effects known as the Damage Checklist, which documents less common toxicities that, although potentially severe, are unlikely to change with varying GC dosing. RESULTS: One hundred and seven (107) toxicity items were included in the pGTI and thirty-two (32) in the Damage Checklist. To assess the degree to which the pGTI corresponds to expert clinical judgement, the investigators ranked 15 cases by clinical judgement from highest to lowest GC toxicity. Expert rankings were then compared to case ranking by the pGTI, yielding excellent agreement (weighted kappa 0.86). The pGTI was migrated to a digital environment following its development and initial validation. The digital platform is designed to ensure ease-of-use in the clinic, rigor in application, and accuracy of scoring. Clinic staff enter vital signs, laboratory results, and medication changes relevant to pGTI scoring. Clinicians record findings for GC myopathy, skin toxicity, mood dysfunction, and infection. The pGTI algorithms then apply the weights to these raw data and calculate scores. Embedded logic accounts for the impact of age- and sex-related reference ranges on several health domains: blood pressure, lipid metabolism, and bone mineral density. Other algorithms account for anticipated changes in the height Z-scores used in the growth domain, thereby addressing a concern unique to GC toxicity in children. The Damage Checklist ensures comprehensive measurement of GC toxicity but does not contribute to pGTI scoring, because the scored domains emphasize manifestations of GC toxicity that are likely to change over the course of a trial. CONCLUSIONS: We describe the development and initial evaluation of a weighted, composite toxicity index for the assessment of morbidity related to GC use in children and adolescents. Developing the pGTI digital platform was essential for performing the nuanced calculations necessary to ensure rigor, accuracy, and ease-of-use in both clinic and research settings.

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.

The 2019 American College of Rheumatology/European League Against Rheumatism Classification Criteria for IgG4-Related Disease.

OBJECTIVE: IgG4-related disease (IgG4-RD) can cause fibroinflammatory lesions in nearly any organ. Correlation among clinical, serologic, radiologic, and pathologic data is required for diagnosis. This work was undertaken to develop and validate an international set of classification criteria for IgG4-RD. METHODS: 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 1,879 subjects (1,086 cases, 793 mimickers), and multicriterion decision analysis to identify, weight, and test potential classification criteria. Two independent validation cohorts were included. RESULTS: A 3-step classification process was developed. First, it must be demonstrated that a potential IgG4-RD case has involvement of at least 1 of 11 possible organs in a manner consistent with IgG4-RD. Second, exclusion criteria consisting of a total of 32 clinical, serologic, radiologic, and pathologic items must be applied; the presence of any of these criteria eliminates the patient from IgG4-RD classification. Third, 8 weighted inclusion criteria domains, addressing clinical findings, serologic results, radiology assessments, and pathology interpretations, are applied. In the first validation cohort, a threshold of 20 points had a specificity of 99.2% (95% confidence interval [95% CI] 97.2-99.8%) and a sensitivity of 85.5% (95% CI 81.9-88.5%). In the second, the specificity was 97.8% (95% CI 93.7-99.2%) and the sensitivity was 82.0% (95% CI 77.0-86.1%). The criteria were shown to have robust test characteristics over a wide range of thresholds. CONCLUSION: 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, epidemiologic, and basic science investigations.

A case of Degos disease in pregnancy.

Degos disease is characterized as a rare systemic vaso-occlusive disorder, although the exact pathophysiology is uncertain. Fewer than 200 patients have been reported in the literature, and only two reports describe the course of the disease during pregnancy. Here, we present the first reported case of the course of pregnancy in a woman with the systemic form of Degos disease. The patient had been diagnosed with Degos prior to pregnancy and was monitored throughout the duration of the pregnancy. Her presentation and treatment are described. There was no further exacerbation secondary to the pregnancy itself; the pregnancy course was uncomplicated and the baby unaffected to date.

Relative urgency for referral from primary care to rheumatologists: the Priority Referral Score.

OBJECTIVE: Timely access to rheumatology consultation is fundamental to appropriate and effective management of patients with musculoskeletal and autoimmune diseases. Yet, for a variety of reasons, limited and delayed access is commonplace. Moreover, information exchange for referral is often inadequate or poorly communicated. The objective of this work was to improve referral from primary care to rheumatology by formulating and testing a clinically coherent, reliable, and non-diagnosis-dependent Priority Referral Score (PRS). METHODS: Using a deliberative process, a clinical panel of 10 primary care providers (PCPs) and rheumatology specialists reviewed clinical case scenarios and engaged in a highly iterative process to develop criteria, definitions, and weights for the PRS, a linear 100-point scale to rate the relative urgency of referral. Following tool formulation, clinicians uninvolved with the process tested the PRS against their clinical judgment. RESULTS: The PRS comprises 8 criteria, with 2-4 levels for each criterion, and each having a weight generated through conjoint analysis, which forced choices around the comparative urgency of all of the criteria and levels. The PRS showed a strong correlation between clinical rankings of rheumatologists and PCPs in both the deliberative panel, and the physicians subsequently involved in the testing of the PRS. CONCLUSION: No standardized priority-setting criteria are available for the full range of primary care referrals to rheumatologists. The PRS had face value with panelists and provided acceptable interrater and intrarater reliability when tested with other rheumatologists and PCPs. Pilot testing with other clinicians and in other settings is justified and prerequisite to use in clinical practice.