A Clinical Picture of Unselected Patients with Systemic Lupus Erythematosus in a Tertiary Hungarian Center-A Spectrum Ranging from Pure Lupus to Overlap Syndromes.

Introduction: Systemic lupus erythematosus (SLE) is a multidimensional disease; however, the association of another systemic autoimmune disease further complicates its clinical presentation. Aim: We decided to investigate whether the association of overlap syndromes is linked with a different clinical picture compared to pure lupus and whether this association changes the sensitivity of the following commonly used criteria: the 2019 European League Against Rheumatism/American College of Rheumatology (EULAR/ACR), the ACR-1997 and the 2012 Systemic Lupus International Collaborating Clinics (SLICC) criteria. Method: We performed a retrospective observational study among 382 patients afflicted with lupus: we measured as much of the full clinical and laboratory picture as possible in an unselected cohort. The diagnosis of SLE and other systemic autoimmune diseases was established by the rheumatologist in routine care and then the authors compared the characteristics of patients with pure lupus and those with overlapping pathologies. The diagnosis rates were compared to those that were determined based on the three classification criteria in order to identify various sensitivities and whether the existence of an overlap affects their rates. The fulfillment of each set of criteria was calculated using an Excel-based automatic calculation. Results: Among the patients, the ACR 1997's sensitivity was 81.2% (310 patients), and the SLICC 2012 criteria achieved 94.5% sensitivity (361 patients). The 2019 EULAR/ACR classification criteria resulted in a slightly lower sensitivity (90.3%-345 patients) when compared to the original publication (96%) due to the lower sensitivity of our anti-nuclear antibody (ANA) test (measured via enzyme-linked immunosorbent assay (ELISA)). Nearly all ANA-negative (21/22-95%) patients showed a positive lupus-associated antibody test. The proportion of ANA-negative cases showed no significant difference among pure and overlap patients. No significant difference was found between patients with overlap (138 patients-36%) and pure SLE (244 patients-64%) through the use of these criteria, with the exception of the SLICC criteria (ACR: 80.4% vs. 81.6%; SLICC: 97.4% vs. 92.6%, p = 0.035; EULAR/ACR 2019: 91.4% vs. 89.6%). Patients with an overlap syndrome were significantly older (55 vs. 50 years, p = 0.001), more likely to suffer from interstitial lung disease (ILD: 20% vs. 11%, p = 0.0343) and less frequently showed class III/IV lupus nephritis (7% vs. 14%, p = 0.029) when compared with their pure lupus counterparts. Conclusion: All investigated criteria regarding sensitivity were similar to the original publication's findings. The sensitivity of the EULAR/ACR 2019 classification criterion in cases with overlap syndrome proved excellent, with results very similar to patients afflicted with pure SLE. In the presence of an overlap syndrome, we found significantly fewer patients with lupus nephritis III/IV but no differences in other typical lupus organ manifestation beyond the kidney, whereas we found a higher proportion of ILD in patients with an overlap, indicating that the presence of an overlap syndrome significantly influences the observed clinical picture in real-world conditions.

IgG4-related disease: Effectiveness evaluation through Umehara-Okazaki 2011 and ACR/EULAR 2019 diagnostic criteria.

BACKGROUND: IgG4-related disease (IgG4-RD) is a rare, systemic immune-mediated fibro-inflammatory condition with an unclear etiology and pathophysiology, potentially affecting multiple organs. It presents with common clinical, radiological, and serological characteristics. This study aims to compare the latest two IgG4-RD classification and diagnostic criteria: Umehara-Okazaki 2011 and ACR/EULAR 2019. MATERIAL AND METHODS: In a retrospective cross-sectional study conducted across two centers from January 2010 to July 2023, we included patients suspected of having IgG4-RD from various hospital departments. Patients finally diagnosed with other pathologies were excluded. The remaining suspected IgG4-RD cases were evaluated using both Umehara-Okazaki 2011 and ACR/EULAR 2019 criteria. RESULTS: Out of 34 patients with a clinical diagnosis of IgG4-RD, the Umehara-Okazaki 2011 classified 20 patients: 5 as definitive, 7 as probable, and 8 as possible cases. Applying the ACR/EULAR 2019 criteria to the same cohort resulted in the diagnosis of 9 patients. Notably, retroperitoneal fibrosis and aortitis were the most prevalent form of presentation, accounting for 25% and 22.2% of cases classified under the 2011 and 2019 criteria, respectively. DISCUSSION: The more recent and stringent ACR/EULAR 2019 criteria focus on histopathology, various forms of presentation, and analytical data, allow for a more accurate classification of patients.

SLE: a cognitive step forward-a synthesis of rethinking theories, causality, and ignored DNA structures.

Systemic lupus erythematosus (SLE) is classified by instinctual classification criteria. A valid proclamation is that these formally accepted SLE classification criteria legitimate the syndrome as being difficult to explain and therefore enigmatic. SLE involves scientific problems linked to etiological factors and criteria. Our insufficient understanding of the clinical condition uniformly denoted SLE depends on the still open question of whether SLE is, according to classification criteria, a well-defined one disease entity or represents a variety of overlapping indistinct syndromes. Without rational hypotheses, these problems harm clear definition(s) of the syndrome. Why SLE is not anchored in logic, consequent, downstream interdependent and interactive inflammatory networks may rely on ignored predictive causality principles. Authoritative classification criteria do not reflect consequent causality criteria and do not unify characterization principles such as diagnostic criteria. We need now to reconcile legendary scientific achievements to concretize the delimitation of what SLE really is. Not all classified SLE syndromes are "genuine SLE"; many are theoretically "SLE-like non-SLE" syndromes. In this study, progressive theories imply imperative challenges to reconsider the fundamental impact of "the causality principle". This may offer us logic classification and diagnostic criteria aimed at identifying concise SLE syndromes as research objects. Can a systems science approach solve this problem?

Performance of the 2022 American College of Rheumatology/European Alliance of Associations for Rheumatology Classification Criteria for antineutrophil cytoplasmic antibody-associated vasculitis in previously diagnosed adult patients from Türkiye.

Objectives: This study aimed to evaluate the applicability of the new 2022 American College of Rheumatology (ACR)/European Alliance of Associations for Rheumatology (EULAR) criteria in Turkish adult patients previously diagnosed with antineutrophil cytoplasmic antibody-associated vasculitis (AAV). Patients and methods: One hundred sixty-four patients (96 males, 68 females; mean age: 49.6±14.4 years; range, 18 to 87 years) diagnosed with AAV by experienced rheumatologists between July 2016 and May 2022 were included in this retrospective cross-sectional study and reclassified based on the 1990 ACR criteria, the European Medicines Agency (EMEA) algorithm, and the 2022 ACR/EULAR criteria. For external validation, 83 patients (48 males, 35 females; mean age: 47.3±17.5 years; range, 19 to 81 years) diagnosed with immunoglobulin (Ig)A vasculitis were included. Results: One hundred twenty-six (76.8%) patients had granulomatosis with polyangiitis (GPA), 13 (7.9%) patients had eosinophilic granulomatosis with polyangiitis (EGPA), and 25 (15.2%) patients had microscopic polyangiitis (MPA). According to the criteria, the number of unclassified patients was nine (5.5%) for both the 2022 ACR/EULAR AAV classification criteria and the EMEA algorithm. The new criteria had an almost perfect agreement with the clinician's diagnosis (Cohen's kappa coefficient [κ]=0.858 for GPA, κ=0.820 for EGPA, and κ=0.847 for MPA). The kappa statistics for agreement of 2022 ACR/EULAR classification criteria with the EMEA algorithm were found 0.794 for GPA, 0.820 for EGPA, and 0.700 for MPA. None of the 83 patients diagnosed with IgA vasculitis could be classified as GPA, EGPA, or MPA using the new ACR/EULAR AAV classification criteria. Conclusion: The 2022 ACR/EULAR classification criteria for AAV showed substantial or perfect agreement with the clinical diagnosis and the EMEA algorithm.

Diagnostic performance of classification criteria for systemic lupus erythematosus: A validation study from Singapore.

Introduction: Classification criteria for systemic lupus erythematosus (SLE) include American College of Rheumatology (ACR) 1997, Systemic Lupus Erythematosus International Collaborating Clinics (SLICC) 2012 and European Alliance of Associations for Rheumatology (EULAR)/ACR 2019 criteria. Their performance in an Asian childhood-onset SLE (cSLE) population remains unclear as the clinical manifestations differ. We aim to evaluate the diagnostic performance in a cSLE cohort in Singapore. Method: Cases were physician-diagnosed cSLE, while controls were children with mixed and undifferentiated connective tissue disease that posed an initial diagnostic challenge. Data were retrospec-tively reviewed to establish the 3 criteria fulfilled at diagnosis and over time. Results: The study population included 120 cSLE cases and 36 controls. At diagnosis, 102 (85%) patients fulfilled all criteria. SLICC-2012 had the highest sensitivity (97.5%, 95% confidence interval [CI] 92.3-99.5), while ACR-1997 had the highest specificity (91.7%, 95% CI 77.5-98.3). All criteria had diagnostic accuracies at more than 85%. Over time, 113 (94%) fulfilled all criteria. SLICC-2012 remained the criteria with the highest sensitivity (99.2%, 95% CI 95.4-99.9), while ACR-1997 had the highest specificity (75.0%, 95% CI 57.8-87.9). Only SLICC-2012 and ACR-1997 had more than 85% diagnostic accuracy over time. Using a cutoff score of ≥13 for EULAR/ACR-2019 criteria resulted in improved diagnostic performance. Conclusion: SLICC-2012 criteria had the highest sensitivity early in the disease course in this first study evaluating the SLE classification criteria performance in a Southeast Asian cSLE cohort, while the ACR-1997 criteria had the highest specificity. Using a cutoff score of ≥13 for EULAR/ACR-2019 improved the diagnostic performance.

Clinical trial eligibility of a real-world connective tissue disease cohort: Results from the LEAP cohort.

INTRODUCTION: Classification criteria aim to identify a homogenous population of patients for research. We aimed to quantify how well phase-III trials in connective tissue diseases (CTDs) represent a real-world cohort. METHODS: A comprehensive review of all major published phase-III trials in CTDs was performed (clinicaltrials.gov). Classification criteria utilised most commonly in clinical trials were applied to a multicentre unselected CTD cohort. RESULTS: There were 42 CTD trials identified, with no trials in mixed (MCTD) or undifferentiated CTD (UCTD). The majority of trials (N = 38, 90 %) required patients to meet classification criteria for their respective disease. Eight (19.0 %) excluded patients with overlapping CTDs and a further two (4.8 %) excluded specific overlapping features, such as pulmonary arterial hypertension. One study explicitly allowed overlap syndromes. Our real-world CTD cohort included 391 patients. Patients with UCTD or MCTD (91/391, 23.3 %) would be excluded from participation in clinical trials for not having an eligible diagnosis. Of patients with primary Sjögren's syndrome (pSS), SLE, systemic sclerosis (SSc) or idiopathic inflammatory myopathy (IIM), 211/300 (70.3 %) met the classification criteria for their respective diagnosis and 24/211 (11.4 %) met criteria for >1 CTD. In total, 187/391 (47.8 %) would be eligible for recruitment, based upon their physician diagnosis, and most stringent trial eligibility criteria. CONCLUSION: In an unselected, real-world CTD cohort, up to half of patients are ineligible for clinical trials due to not meeting classification criteria, overlapping features or a lack of trials within their primary disease. To address this inequality in access to novel therapies, clinical trial design should evolve eligibility criteria in CTDs.

Assessment of the 2023 ACR/EULAR antiphospholipid syndrome classification criteria in a Chinese cohort: Impact on clinical practice.

OBJECTIVES: To evaluate the effectiveness of the 2023 ACR/EULAR criteria for antiphospholipid syndrome (APS) in a Chinese cohort, and compare them with the Sapporo and revised Sapporo criteria. METHODS: A cohort comprising 436 patients diagnosed with APS and 514 control subjects was enrolled, including 83 with seronegative APS and 86 classified as antiphospholipid antibody (aPL) carriers. We assessed IgG and IgM anticardiolipin antibodies (aCL) and anti-ß2-glycoprotein I (aß2GPI) antibodies using ELISA, along with a systematic collection of lupus anticoagulant data. Subsequently, we compared the sensitivity and specificity across the three classification criteria. RESULTS: The 2023 ACR/EULAR criteria exhibited improved specificity at 98 %, surpassing the revised Sapporo (90 %) and original Sapporo (91 %) criteria. However, this came with decreased sensitivity at 82 %, in contrast to higher sensitivities in the revised Sapporo (98 %) and Sapporo (91 %) criteria. Examining individual components sheds light on the scoring system's rationale within the new criteria. The inclusion of microvascular thrombosis, cardiac valve disease, and thrombocytopenia improved the identification of nine patients previously classified as "probable APS". Insufficient scoring in 78 previously diagnosed APS individuals was linked to traditional risk factor evaluations for thrombotic events, the emphasis on determining whether obstetric events are linked to severe preeclampsia (PEC) or placental insufficiency (PI), and the lower scores assigned to IgM aCL and/or aß2GPI antibody. Seronegative APS remained a challenge, as non-criteria aPL and other methods were not included. CONCLUSIONS: The new criteria presented notable advancements in specificity. This study provides detailed insights into the strengths and possible challenges of the 2023 ACR/EULAR criteria, enhancing our understanding of their impact on clinical practice.

Assessment and comparison of the 2023 ACR/EULAR APS criteria with the revised Sapporo criteria.

OBJECTIVE: To analyze antiphospholipid antibody (aPL)-positive patients using the 2023 American College of Rheumatology/The European Alliance of Associations for Rheumatology (ACR/EULAR) antiphospholipid syndrome (APS) classification criteria and compare the revised Sapporo criteria and the 2023 ACR/EULAR criteria and evaluate whether the 2023 ACR/EULAR criteria provide added value over the revised Sapporo criteria. METHODS: In this descriptive study, 94 aPL-positive patients (with or without APS diagnosis) were identified from two hospital-based registries (Gazi and Hacettepe University). Patients were classified into four groups to compare both criteria sets. These four groups are as follows: (1) patients classified with only the revised Sapporo criteria; (2) patients classified with only the 2023 ACR/EULAR APS criteria; (3) patients classified with both two criteria sets; and (4) patients classified with neither two criteria set. RESULTS: Of the 94 patients, 11 were classified with only the revised Sapporo criteria; one with only the 2023 ACR/EULAR APS criteria; 52 with both criteria sets; and 30 with neither set of criteria. For these 94 patients, the operating characteristics of the 2023 ACR/EULAR APS criteria, using the revised Sapporo criteria as the gold standard, the 2023 ACR/EULAR APS entry criteria demonstrated 100% sensitivity, and the 2023 ACR/EULAR APS classification criteria demonstrated 98% specificity and 82.5% sensitivity. CONCLUSION: The study emphasizes the importance of recognizing differences in clinical manifestations, such as early pregnancy loss without severe preeclampsia (PEC) and/or severe placental insufficiency (PI) and calls for a nuanced discussion on anticardiolipin (aCL) and anti-beta 2-glycoprotein-I (anti-ß2GPI) immunoglobulin G (IgG) cutoff values.

Knowledge, Attitudes, and Practices of Moroccan Community Rheumatologists' Regarding the Management of Non-radiographic Axial Spondyloarthritis: A National Cross-Sectional Study.

Introduction Non-radiographic axial spondyloarthritis (nr-axSpA) is within the spectrum of axial spondyloarthritis (axSpA). The emergence of the nr-axSpA concept, defined by the absence of significant erosive damage to the sacroiliac joints, has prompted numerous initiatives aimed at enhancing the early detection and management of this condition. The aim of the study was to assess the knowledge, attitudes, and practices related to the diagnosis and management of nr-axSpA by rheumatologists in Morocco. Methods We conducted a cross-sectional online survey among the rheumatologist community in Morocco. Rheumatologists received via e-mail a structured Google Forms (Google Inc., Mountainview, CA) questionnaire divided into four sections: sociodemographic data of rheumatologists, knowledge, attitudes, and practices related to the diagnosis and treatment management of nr-axSpA. Results A total of 110 rheumatologists (mean age of 44±13 years, 77.3% females, median professional experience of 12 years (4, 75; 26.25 years)) participated in the survey (response rate of 25%). Most responders reported a diagnosis delay issue in spondyloarthritis (SpA) (93.6%); 70.9% of rheumatologists incorrectly regarded the 2009 Assessment of Spondyloarthritis International Society (ASAS) classification criteria for axSpA as diagnostic criteria. Rheumatologists' awareness of recommended magnetic resonance imaging (MRI) sequences for detecting sacroiliac joint inflammation and structural changes in SpA varied significantly, from 69.1% to 14.5%. Their knowledge of additional subchondral edema cases in these joints, beyond SpA, ranged from 48.2% to 87.3%. Almost all rheumatologists believed that the use of sacroiliac MRI would contribute to the early diagnosis of axSpA (97.3%) but could also lead to false positive diagnoses, according to 47.3% of rheumatologists; 73.6% believed that incorrectly using the 2009 ASAS classification criteria as diagnostic criteria in nr-axSpA could also result in false-positive diagnoses. In their practice, 2009 ASAS classification criteria were used as diagnostic criteria in axSpA by 39.1% of rheumatologists. Of the total participants, 91.8% indicated that they approach nr-axSpA similarly to radiographic axial spondyloarthritis, with disparities in recommendations of biological therapies. Conclusion Our survey provides insight into the current status of nr-axSpA management among Moroccan rheumatologists. It also addresses concerns regarding the risk of false positive diagnoses when using the 2009 ASAS classification criteria for axSpA as diagnostic criteria by rheumatologists and the potential risk of misdiagnosis associated with excessive reliance on MRI, despite its utility for early diagnosis.

Axial Spondyloarthritis: an overview of the disease.

Axial Spondyloarthritis (axSpA) is a chronic, inflammatory, immune-mediated rheumatic disease that comprises two subsets, non-radiographic and radiographic axSpA, and belongs to a heterogeneous group of spondyloarthritides (SpA). Over the years, the concept of SpA has evolved significantly, as reflected in the existing classification criteria. Considerable progress has been made in understanding the genetic and immunological basis of axSpA, in studying the processes of chronic inflammation and pathological new bone formation, which are pathognomonic for the disease. As a result, new medication therapies were developed, which bring more effective ways for disease control. This review presents a brief overview of the literature related to these aspects of disease after summarising the available information on the topic that we considered relevant. Specifically, it delves into recent research illuminating the primary pathological processes of enthesitis and associated osteitis in the context of inflammation in axSpA. The exploration extends to discussion of inflammatory pathways, with a particular focus on Th1/Th17-mediated immunity and molecular signaling pathways of syndesmophyte formation. Additionally, the review sheds light on the pivotal role of cytokine dysregulation, highlighting the significance of the IL-23/17 axis and TNF-α in this intricate network of immune responses which is decisive for therapeutic approaches in the disease.

Comparison of systemic lupus international collaborating clinics 2012 classification criteria and European league against rheumatism/American college of rheumatology 2019 classification criteria for early detection of childhood onset systemic lupus erythematosus (multi-center study).

OBJECTIVE: To assess the performance of the new EULAR/ACR criteria, particularly for early detection of cSLE, in comparison to the SLICC criteria among the pediatric population in multiple centers in Saudi Arabia. METHODS: We conducted a retrospective study that enrolled pediatric patients up to the age of 14 years who've been diagnosed with SLE and followed in pediatric rheumatology clinics at 9 multi-tertiary hospitals in Saudi Arabia from 2010 to 2021 as a case group and were compared to a similar group of pediatric patients who've had defined rheumatological diseases other than SLE with a positive ANA titer (≥1:80) as controls. In total, 245 patients were included and distributed as 129 cases (diagnosed by expert pediatric rheumatologists) versus 116 patients in the control group. All relevant clinical information, including history, physical examination findings, and laboratory tests, was documented at the initial presentations. Then, the two sets of SLE classification criteria were applied to both groups to define who's going to meet both or either one of them. The exclusion criteria included those who had insufficient data or had overlapping or undifferentiated diseases. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), receiver operating curve (ROC), and accuracy were calculated for SLICC 2012 and EULAR/ACR 2019 criteria (total scores≥ 10 and ≥ 13). We performed a Chi-squared test to compare sensitivity and specificity of SLICC 2012 and EULAR/ACR 2019. RESULTS: For SLICC (cut-off ≥4 criteria), the sensitivity was found to be 96.9% (95% CI 92.6%-99.4%) and the specificity was 94.8% (95% CI 89.6%-98.32%), with PPV and NPV of 95.4% and 96.5%, respectively. The ROC for it was 0.96 (95% CI 0.93-0.99), and this criterion had an accuracy of 95%. Regarding EULAR/ACR (total score ≥ 10), the performance measure showed a sensitivity of 99.2% and a specificity of 86.2%. Similarly, PPV was 88.9%; while NPV was a little higher (99.0%) than SLICC. The ROC for EULAR/ACR (total score ≥ 10) was 0.93 (95% CI 0.89-0.96), and this criterion had an accuracy of 93%. However, there was no statistically significant difference between the sensitivity and specificity of either using SLICC or EULAR/ACR (total score ≥ 10), as reflected by a p-value of 0.86 using the Chi-squared test. Although applying the EULAR/ACR with a total score of ≥ 13 revealed lower sensitivity (93.8%) than both the SLICC and the EULAR/ACR (total score ≥ 10), the specificity for it was found to increase up to 91.4% (85.7-96.2%) compared to the (86.2%) specificity of the EULAR/ACR (total score ≥ 10). CONCLUSION: In this cohort among the Saudi population with childhood-onset SLE, the new EULAR/ACR 2019 criteria efficiently enable early detection of SLE, although a more frequent rate of false positives was observed with them. Escalating the total score from ≥ 10 to ≥ 13 in the cSLE population improved the specificity close to that of SLICC 2012. Further prospective studies in pediatrics need to be done for the validation of a cut- off score of ≥ 13 in cSLE rather than the traditional score of ≥ 10 in aSLE.

[First classification criteria for diseases caused by calcium pyrophosphate deposition (CPPD)-Translation, explanation and assessment]. / Erste Klassifikationskriterien für durch Kalziumpyrophosphatablagerungen verursachte Erkrankungen ­ Übersetzung, Erläuterung und Bewertung.

AIM: For diseases caused by calcium pyrophosphate deposition (CPPD), validated classification criteria were previously lacking. In this article the recently developed and validated classification criteria are translated, explained, and assessed. METHODS: In recent years a multinational research group developed classification criteria for CPPD disease with the support by the European Alliance of Associations for Rheumatology (EULAR) and the American College of Rheumatology (ACR), following an established method. The developed criteria were finally validated in an independent cohort. The translation and annotation of the new first classification criteria were carried out in an iterative procedure in consensus with the authors. RESULTS: The presence of a crowned dens syndrome or calcium pyrophosphate crystals in the synovial fluid in patients with pain, swelling or sensitivity of the joints (entry criterion) is sufficient for the classification as CPPD disease, where the symptoms cannot be completely explained by another rheumatic disease (exclusion criterion). If these symptoms are not present, a count of more than 56 points based on weighted criteria comprised of clinical features and the results of laboratory and imaging investigations can be included for classification as a CPPD disease. These criteria had a sensitivity of 92.2% and a specificity of 87.9% in the derivation cohorts (190 CPPD cases and 148 mimics), whereas the sensitivity was 99.2% and the specificity 92.5% in the validation cohorts (251 CPPD cases and 162 mimics). CONCLUSION: The ACR/EULAR classification criteria 2023 of a CPPD disease will facilitate clinical research in this field. The use in the clinical routine will show how practical the criteria are.

The greatest contribution to medical science is the transformation from studying symptoms to studying their causes-the unrelenting legacy of Robert Koch and Louis Pasteur-and a causality perspective to approach a definition of SLE.

The basic initiative related to this study is derived from the fact that systemic lupus erythematosus (SLE) is a unique and fertile system science subject. We are, however, still far from understanding its nature. It may be fair to indicate that we are spending more time and resources on studying the complexity of classified SLE than studying the validity of classification criteria. This study represents a theoretical analysis of current instinctual SLE classification criteria based on "the causality principle." The discussion has its basis on the radical scientific traditions introduced by Robert Koch and Louis Pasteur. They announced significant changes in our thinking of disease etiology through the implementation of the modern version of "the causality principle." They influenced all aspects of today's medical concepts and research: the transformation of medical science from studies of symptoms to study their causes, relevant for monosymptomatic diseases as for syndromes. Their studies focused on bacteria as causes of infectious diseases and on how the immune system adapts to control and prevent contagious spreading. This is the most significant paradigm shift in the modern history of medicine and resulted in radical changes in our view of the immune system. They described acquired post-infection immunity and active immunization by antigen-specific vaccines. The paradigm "transformation" has a great theoretical impact also on current studies of autoimmune diseases like SLE: symptoms and their cause(s). In this study, the evolution of SLE classification and diagnostic criteria is discussed from "the causality principle" perspective, and if contemporary SLE classification criteria are as useful as believed today for SLE research. This skepticism is based on the fact that classification criteria are not selected based on cogent causal strategies. The SLE classification criteria do not harmonize with Koch's and Pasteur's causality principle paradigms and not with Witebsky's Koch-derived postulates for autoimmune and infectious diseases. It is not established whether the classification criteria can separate SLE as a "one disease entity" from "SLE-like non-SLE disorders"-the latter in terms of SLE imitations. This is discussed here in terms of weight, rank, and impact of the classification criteria: Do they all originate from "one basic causal etiology"? Probably not.

Antiphospholipid Syndrome: To Classify or Not to Classify?

Antiphospholipid syndrome (APS) is a systemic autoimmune disorder resulting in thrombosis, microvascular disease, morbidity in pregnancy, and/or non-thrombotic manifestations. The recently introduced 2023 American College of Rheumatology (ACR) and European Alliance of Associations for Rheumatology (EULAR) APS classification criteria, with significantly higher specificity compared to the revised Sapporo criteria, now reflect the current thinking about APS and provide a new foundation for future APS research. The purpose of this short commentary is to discuss the appropriate circumstances under which the 2023 ACR/EULAR classification criteria could be used and to demonstrate how the new criteria can be applied to simple case scenarios.

Clinical presentation and outcomes in patients with antiphospholipid syndrome-associated adrenal hemorrhage. A multicenter cohort study and systematic literature review.

BACKGROUND: Adrenal hemorrhage (AH) can occur in patients with antiphospholipid Syndrome (APS). We aimed to characterize the clinical manifestations, treatments, and outcomes of patients presenting with APS-associated AH (APS-AH) through a retrospective cohort and a systematic literature review (SLR). METHODS: We performed a mixed-source approach combining a multicenter cohort with an SLR of patients with incident APS-AH. We included patients from Mayo Clinic and published cases with persistent positivity for antiphospholipid antibodies and presenting with AH, demonstrated by imaging or biopsy. We extracted demographics, clinical characteristics, laboratory findings, treatment strategies, and outcomes (primary adrenal insufficiency and mortality). We used Kaplan-Meier and Cox models for survival analysis. RESULTS: We included 256 patients in total, 61 (24%) from Mayo Clinic and 195 (76%) from the SLR. The mean age was 46.8 (SD 15.2) years, and 45% were female. 69% of patients had bilateral adrenal involvement and 64% presented adrenal insufficiency. The most common symptoms at presentation were abdominal pain in 79%, and nausea and vomiting 46%. Hyponatremia (77%) was the most common electrolyte abnormality. Factors associated with primary adrenal insufficiency were bilateral adrenal involvement at initial imaging (OR 3.73, CI; 95%, 1.47-9.46) and anticardiolipin IgG positivity (OR 3.80, CI; 95%, 1.30-11.09). The survival rate at five years was 82%. History of stroke was associated with 3.6-fold increase in mortality (HR 3.62, 95% CI; 1.33-9.85). CONCLUSION: AH is a severe manifestation of APS with increased mortality. Most patients developed permanent primary adrenal insufficiency, particularly those positive for anticardiolipin IgG and bilateral adrenal involvement.

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

OBJECTIVES: To improve the definitions of inflammatory arthritis within the musculoskeletal (MSK) domain of the BILAG-2004 index by incorporating imaging findings and clinical features predictive of response to treatment. METHODS: The BILAG MSK Subcommittee proposed revisions to the BILAG-2004 index definitions of inflammatory arthritis, based on review of evidence in two recent studies. Data from these studies were pooled and analysed to determine the impact of the proposed changes on the severity grading of inflammatory arthritis. RESULTS: The revised definition for severe inflammatory arthritis includes definition of 'basic activities of daily living'. For moderate inflammatory arthritis, it now includes synovitis, defined by either observed joint swelling or MSK US evidence of inflammation in joints and surrounding structures. For mild inflammatory arthritis, the definition now includes reference to symmetrical distribution of affected joints and guidance on how US may help re-classify patients as moderate or no inflammatory arthritis. Data from two recent SLE trials were analysed (219 patients). A total of 119 (54.3%) were graded as having mild inflammatory arthritis (BILAG-2004 Grade C). Of these, 53 (44.5%) had evidence of joint inflammation (synovitis or tenosynovitis) on US. Applying the new definition increased the number of patients classified as moderate inflammatory arthritis from 72 (32.9%) to 125 (57.1%), while patients with normal US (n = 66/119) could be recategorized as BILAG-2004 Grade D (inactive disease). CONCLUSIONS: Proposed changes to the definitions of inflammatory arthritis in the BILAG-2004 index will result in more accurate classification of patients who are more or less likely to respond to treatment.

SLE criteria are by necessity still based on clinical (and immunological) criteria items.

INTRODUCTION: The 2019 European League Against Rheumatism/American College of Rheumatology (EULAR/ACR) classification criteria for systemic lupus erythematosus (SLE) rely on clinical and routine immunological items. The criteria have anti-nuclear antibodies (ANA) as an obligatory entry criterion; items are weighted and ordered in domains. While demonstrating good sensitivity and specificity, the lack of a more molecular approach to some came as a disappointment. AREAS COVERED: Based on a non-systematic literature search, this review covers items investigated in the EULAR/ACR classification criteria project, but not included in the set of criteria. It demonstrates data on the importance of the criteria and analyses implications of multiomics studies started around the same time as the criteria project. We also discuss data on the type-I interferon signature and on other cytokines, as well as on complement proteins and their split products. The final part deals with the variability in disease and the apparently random pattern of autoantibodies and organ manifestations in individual patients. EXPERT OPINION: We believe that the EULAR/ACR criteria are a relevant step toward the right direction. A more uniform molecular approach will not be feasible as long as the molecular mechanisms underlying the tendency toward producing multiple autoantibodies are not better understood.

Pediatric IgG4-related disease: a descriptive review.

INTRODUCTION: IgG4-related disease (IgG4-RD) is an immune-mediated systemic fibroinflammatory condition characterized by serum IgG4 elevation and IgG4-positive plasma cell infiltration into various organs. It generally occurs in elderly males. Pediatric cases have been reported, albeit rarely, accordingly lack of recognition of such cases could delay therapeutic intervention leading to poorer outcomes. AREAS COVERED: The present review is a descriptive review of all published case reports, cohort studies, and reviews of pediatric IgG4-RD listed in PubMed. Characteristics of pediatric IgG4-RD were clarified, including sex, organ involvement, serological and histological findings, and treatment. We assessed how many published cases met current classification and comprehensive diagnostic criteria. EXPERT OPINION: The characteristics of pediatricIgG4-RD differed from adult IgG4-RD in terms of sex and involved organs. There was no clear male dominance in numbers of cases, and surface organ involvement such as ophthalmic diseases were more common in the pediatric IgG4-RD. Organ involvement tended to be indolent and unilateral, causing difficulty in definitively diagnosing pediatric IgG4-RD. Only about 20% of published cases met IgG4-RD classification or comprehensive diagnostic criteria. Physicians should be careful in diagnosing pediatric IgG4-RD after excluding mimickers. International collaboration toward high-quality evidence to support diagnosis and treatment of pediatric IgG4-RD is advised.

Evaluation of Ministry of Health, Labour and Welfare diagnostic criteria for antineutrophil cytoplasmic antibody-associated vasculitis compared to ACR/EULAR 2022 classification criteria.

OBJECTIVE: This study aimed to evaluate the Ministry of Health, Labour and Welfare (MHLW) diagnostic criteria for antineutrophil cytoplasmic antibody-associated vasculitis compared to the new American College of Rheumatology/European Alliance of Associations for Rheumatology 2022 criteria. METHODS: Two nationwide cohort studies were used, and participants were categorised as having eosinophilic granulomatosis with polyangiitis, granulomatosis with polyangiitis (GPA), or microscopic polyangiitis (MPA) according to the American College of Rheumatology/European Alliance of Associations for Rheumatology 2022 and MHLW criteria. RESULTS: Of the entire patient population, only 10 (2.1%) were unclassifiable according to the MHLW probable criteria, while a significant number of patients (71.3%) met at least two criteria. The MHLW probable criteria for MPA had some challenges in differentiating between MPA and eosinophilic granulomatosis with polyangiitis, and the same was true for MHLW probable criteria for GPA in differentiating MPA from GPA. Nevertheless, improved classification results were obtained when the MHLW probable criteria were applied in the order of eosinophilic granulomatosis with polyangiitis, MPA, and GPA. CONCLUSIONS: The application of MHLW criteria could categorise a substantial number of patients with antineutrophil cytoplasmic antibody-associated vasculitis into one of the three antineutrophil cytoplasmic antibody-associated vasculitis diseases. The classification was in accordance with the American College of Rheumatology/European Alliance of Associations for Rheumatology 2022 criteria when considering the order of application.

Classification of Atretic Small Antral Follicles in the Human Ovary.

The reproductive lifespan in humans is regulated by a delicate cyclical balance between follicular recruitment and atresia in the ovary. The majority of the small antral follicles present in the ovary are progressively lost through atresia without reaching dominance, but this process remains largely underexplored. In our study, we investigated the characteristics of atretic small antral follicles and proposed a classification system based on molecular changes observed in granulosa cells, theca cells, and extracellular matrix deposition. Our findings revealed that atresia spreads in the follicle with wave-like dynamics, initiating away from the cumulus granulosa cells. We also observed an enrichment of CD68+ macrophages in the antrum during the progression of follicular atresia. This work not only provides criteria for classifying three stages of follicular atresia in small antral follicles in the human ovary but also serves as a foundation for understanding follicular degeneration and ultimately preventing or treating premature ovarian failure. Understanding follicular remodeling in the ovary could provide a means to increase the number of usable follicles and delay the depletion of the follicular reserve, increasing the reproductive lifespan.