Myeloperoxidase (MPO)-specific antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (MPO-ANCA-associated vasculitis) is one of two major ANCA-associated vasculitis variants characterised by systemic necrotising vasculitis with few or no immune deposits. MPO-ANCA-associated vasculitis predominantly affects small blood vessels and, in contrast to its counterpart proteinase 3-ANCA-associated vasculitis, is generally not associated with granulomatous inflammation. The kidneys and lungs are the most commonly affected organs. The pathogenesis of MPO-ANCA-associated vasculitis is characterised by loss of tolerance to the neutrophil enzyme MPO. This loss of tolerance leads to a chronic immunopathological response where neutrophils become both the target and effector of autoimmunity. MPO-ANCA drives neutrophil activation, leading in turn to tissue and organ damage. Clinical trials have improved the therapeutic approach to MPO-ANCA-associated vasculitis. However, there remains substantial unmet need regarding relapse frequency, toxicity of current treatment, and long-term morbidity. In this Series paper, we present the current state of research regarding pathogenesis, diagnosis, and treatment of MPO-ANCA-associated vasculitis.

Proteinase 3 (PR3)-specific antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis is one of two major ANCA-associated vasculitis variants and is pathogenically linked to granulomatosis with polyangiitis (GPA). GPA is characterised by necrotising granulomatous inflammation that preferentially affects the respiratory tract. The small vessel vasculitis features of GPA are shared with microscopic polyangiitis. Necrotising granulomatous inflammation of GPA can lead to PR3-ANCA and small vessel vasculitis via activation of neutrophils and monocytes. B cells are central to the pathogenesis of PR3-ANCA-associated vasculitis. They are targeted successfully by remission induction and maintenance therapy with rituximab. Relapses of PR3-ANCA-associated vasculitis and toxicities associated with current standard therapy contribute substantially to remaining mortality and damage-associated morbidity. More effective and less toxic treatments are sought to address this unmet need. Advances with cellular and novel antigen-specific immunotherapies hold promise for application in autoimmune disease, including PR3-ANCA-associated vasculitis. This Series paper describes the inter-related histopathological and clinical features, pathophysiology, as well as current and future targeted treatments for PR3-ANCA-associated vasculitis.

Spinal pathologies develop in patients of all ages and may have various underlying factors. These factors include, among others, myofascial pain syndromes, disc herniation and spinal degeneration. Treatment alone, both causal and symptomatic, is not always sufficient in certain situations. The aim of this paper is to discuss the question of comprehensive treatment of spine pathologies focusing on a three-stage treatment concept. An important aspect is to determine the risk factors and their reduction, or at least modification, i.e. the first stage of the discussed treatment concept. Then, medical treatment aimed at a specific pathology, including both conservative and surgical methods, allows the cause of the pathology to be removed, i.e. the second stage of the discussed concept. And finally, timely and specialized, broadly understood rehabilitation allowing to maintain the effect of medical therapy. The implemented rehabilitation can be considered as the third stage of the discussed treatment concept.

Autoimmune diseases (ADs) and myelodysplastic syndrome (MDS) may be associated in approximately 10-20% of cases. Although this association has been well recognized, it is not always easily diagnosed. The exact physiopathological mechanism involved has yet to be determined but seems to be multifactorial. The therapeutic decision is not well codified and often represents a challenge. But overall, glucocorticosteroids have generally proven to be effective at the expense of a high incidence of dependence and relapse. This review aims to summarize and analyze all aspects of this association to provide an overview for practitioners and clinicians. A scientific search in databases (PubMed, Scopus, Web of Science, Google Scholar) was conducted using a combination of key words such as autoimmune diseases, myelodysplastic syndromes, and association. Articles from 1992 to 2022 were considered and relevant data were collected and summarized to provide a coherent detailed overview of the coexistence of ADs and MDS.

Axial spondyloarthritis (axSpA) is an inflammatory joint disease, in which the dominant symptom is inflammatory back pain. It affects approximately 1% of the population, with a higher incidence in males. Spinal pain associated with spondyloarthritis is referred to as inflammatory back pain. In clinical practice, it is extremely important to be able to assess the activity of inflammatory back diseases and to select appropriate treatment and monitor the therapy. Currently, two main tools are used for assessment of the activity of axial spondyloarthritis: BASDAI (Bath Ankylosing Spondylitis Disease Activity Index) and ASDAS (Ankylosing Spondylitis Disease Activity Score). The BASDAI is a tool used for years for assessment of disease activity, determining eligibility for treatment, and making decisions about continuation of therapy. Since BASDAI depends entirely on patient self-assessment, it is considered less objective than the ASDAS index. In turn, the latter includes not only answers to questions provided by the patient but also a parameter of inflammation such as erythrocyte sedimentation rate or C-reactive protein (CRP). Additionally, increasing numbers of studies report advantages of the ASDAS index over BASDAI. Moreover, as indicated by ASAS/EULAR (Assessment in Spondyloarthritis International Society/European Alliance of Associations for Rheumatology) 2022, ASDAS, especially ASDAS-CRP is the preferred tool for assessment of the activity of axSpA, whereas BASDAI is used only when the evaluation of the ASDAS is not possible. This paper presents the definition and symptoms of axSpA and reviews the latest research on ASDAS and BASDAI, with emphasis on the objectivity of the ASDAS assessment also presenting the doubts and limitations concerning this tool.

In juvenile idiopathic arthritis we have seen remarkable progress in the number of available licensed biological and small molecule treatments in the past two decades, leading to improved outcomes for patients. Designing clinical trials for these therapeutics is fraught with ethical, legislative, and practical challenges. However, many aspects of current clinical trial design in juvenile idiopathic arthritis do not meet the needs of patients and clinicians. Commonly used withdrawal trial designs raise substantial ethical concerns for patients and families who believe that they do not enable evidence-based and patient-centred decisions around medication choices. In this Viewpoint, we present the personal views of a patient and parent network that is of the opinion that current trial design in juvenile idiopathic arthritis is failing children and young people with juvenile idiopathic arthritis and set out the need for change informed by lived experience.

Anti-neutrophil cytoplasm antibodies (ANCA)-associated vasculitides (AAV) are rare conditions characterized by inflammatory cell infiltration in small blood vessels, leading to tissue necrosis. While most patients with AAV present antibodies against either myeloperoxidase (MPO) or proteinase 3 (PR3), rare cases of dual positivity for both antibodies (DP-ANCA) have been reported, and their impact on the clinical picture remains unclear. The goal of this study was to investigate the clinical implications, phenotypic profiles and outcomes of patients with DP-ANCA.

To investigate the risk of DM and evaluate the impact of SLE therapies on the risk of developing DM in patients with SLE.

To evaluate the efficacy of pharmacological interventions for treating early-stage, pain predominant, adhesive capsulitis, also known as frozen shoulder.

Rheumatoid arthritis (RA) has an estimated heritability of nearly 50%, which is particularly high in seropositive RA. HLA alleles account for a large proportion of this heritability, in addition to many common single-nucleotide polymorphisms with smaller individual effects. Low-frequency and rare variants, such as those captured by next-generation sequencing, can also have a large role in heritability in some individuals. Rare variant discovery has informed the development of drugs such as inhibitors of PCSK9 and Janus kinases. Some 34 low-frequency and rare variants are currently associated with RA risk. One variant (19:10352442G>C in TYK2) was identified in five separate studies, and might therefore represent a promising therapeutic target. Following a set of best practices in future studies, including studying diverse populations, using large sample sizes, validating RA and serostatus, replicating findings, adjusting for other variants and performing functional assessment, could help to ensure the relevance of identified variants. Exciting opportunities are now on the horizon for genetics in RA, including larger datasets and consortia, whole-genome sequencing and direct applications of findings in the management, and especially treatment, of RA.

Previous attempts to pool prevalence studies in PsA have failed to take account of important methodological differences between studies that may have created biased estimates. The aim of this review is to estimate the prevalence of PsA within the adult general population worldwide, considering potential differences between population-based and health administrative studies separately.

WD repeat- and FYVE domain-containing protein 4 (WDFY4), coded by a gene on 10q11.23, is a member of the BEACH (Beige and Chediak-Higashi) domain-containing family. Genome-wide association studies identified WDFY4 variants as a risk factor for SLE in Asian and European populations. WDFY4 variants are also associated with RA and primary biliary cholangitis, in different ancestry populations. The WDFY4 protein plays an essential role in the cross-presentation of classic dendritic cells, reactive oxygen species-induced apoptosis of CD8+ T cells, and non-canonical autophagic activity in B cells. A novel variant rs7919656 was identified in Japanese clinically amyopathic dermatomyositis patients, with a highly expressed truncated isoform augmenting the melanoma differentiation-associated gene 5 (MDA5) signalling pathway. The same variant was later found to be significantly associated with RP-ILD in Chinese MDA5+DM patients. Here, we briefly review the association of WDFY4 with autoimmune diseases and its known function in the immune response.

Historically, osteoporosis has been viewed as a disease of women, with research, trials of interventions and guidelines predominantly focused as such. It is apparent, however, that this condition causes a substantial health burden in men also, and that its assessment and management must ultimately be addressed across both sexes. In this article, an international multidisciplinary working group of the European Society for Clinical and Economic Aspects of Osteoporosis, Osteoarthritis and Musculoskeletal Diseases presents GRADE-assessed recommendations for the diagnosis, monitoring and treatment of osteoporosis in men. The recommendations are based on a comprehensive review of the latest research related to diagnostic and screening approaches for osteoporosis and its associated high fracture risk in men, covering disease burden, appropriate interpretation of bone densitometry (including the use of a female reference database for densitometric diagnosis in men) and absolute fracture risk, thresholds for treatment, and interventions that can be used therapeutically and their health economic evaluation. Future work should specifically address the efficacy of anti-osteoporosis medications, including denosumab and bone-forming therapies.

APS is an autoimmune disorder with life-threatening complications that, despite therapeutic advantages, remains associated with thrombotic recurrences and treatment failure. The role of complement activation in APS pathogenesis is increasingly recognized, specifically in obstetric APS. However, its exact role in thrombotic APS and on the severity of the disease is not yet fully elucidated. Further mechanistic studies are needed to delineate the role of complement activation in the various APS clinical manifestations with aim to identify novel markers of disease severity, together with clinical trials to evaluate the efficacy of complement inhibition in APS. This could ultimately improve risk stratification in APS, patient-tailored targeted therapy with complement inhibition identified as an adjunctive treatment. This article reviews current findings and challenges about complement activation in APS, discusses the potential role of platelet-mediated complement activation in this setting and provides an overview of clinical implications and current therapeutics.

Gout is the most common form of inflammatory arthritis worldwide and is characterized by painful recurrent flares of inflammatory arthritis that are associated with a transiently increased risk of adverse cardiovascular events. Furthermore, gout is associated with multiple cardiometabolic-renal comorbidities such as type 2 diabetes, chronic kidney disease and cardiovascular disease. These comorbidities, potentially combined with gout flare-related inflammation, contribute to persistent premature mortality in gout, independently of serum urate concentrations and traditional cardiovascular risk factors. Although better implementation of standard gout care could improve gout outcomes, deliberate efforts to address the cardiovascular risk in patients with gout are likely to be required to reduce mortality. Sodium-glucose cotransporter type 2 (SGLT2) inhibitors are approved for multiple indications owing to their ability to lower the risk of all-cause and cardiovascular death, hospitalizations for heart failure and chronic kidney disease progression, making them an attractive treatment option for gout. These medications have also been shown to lower serum urate concentrations, the causal culprit in gout risk, and are associated with a reduced risk of incident and recurrent gout, potentially owing to their purported anti-inflammatory effects. Thus, SGLT2 inhibition could simultaneously address both the symptoms of gout and its comorbidities.

Tyrosine kinase 2 (TYK2) is a member of the JAK kinase family of intracellular signalling molecules. By participating in signalling pathways downstream of type I interferons, IL-12, IL-23 and IL-10, TYK2 elicits a distinct set of immune events to JAK1, JAK2 and JAK3. TYK2 polymorphisms have been associated with susceptibility to various rheumatic diseases including systemic lupus erythematosus and dermatomyositis. In vitro and animal studies substantiate these findings, highlighting a role for TYK2 in diseases currently managed by antagonists of cytokines that signal through TYK2. Various inhibitors of TYK2 have now been studied in human disease, and one of these inhibitors, deucravacitinib, has now been approved for the treatment of psoriasis. Phase II trials of deucravacitinib have also reported positive results in the treatment of psoriatic arthritis and systemic lupus erythematosus, with a preliminary safety profile that seems to differ from that of the JAK1, JAK2 and JAK3 inhibitors. Two other inhibitors of TYK2, brepocitinib and ropsacitinib, are also in earlier stages of clinical trials. Overall, TYK2 inhibitors hold promise for the treatment of a distinct spectrum of autoimmune diseases and could potentially have a safety profile that differs from other JAK inhibitors.

To describe the evidence of methotrexate (MTX) initiation strategies in patients with rheumatoid arthritis (RA) and, in the case of non-responders, analyse the efficacy and safety of route and dose optimisation.

In genomic medicine, the concept of genetically transitional disease (GTD) refers to cases in which gene mutation is necessary but not sufficient to cause disease. In this Perspective, we apply this novel concept to rheumatic diseases, which have been linked to hundreds of genetic variants via association studies. These variants are in the 'grey zone' between monogenic variants with large effect sizes and common susceptibility alleles with small effect sizes. Among genes associated with rare autoinflammatory diseases, many low-frequency and/or low-penetrance variants are known to increase susceptibility to systemic inflammation. In autoimmune diseases, hundreds of HLA and non-HLA genetic variants have been revealed to be modest- to moderate-risk alleles. These diseases can be reclassified as GTDs. The same concept could apply to many other human diseases. GTD could improve the reporting of genetic testing results, diagnostic yields, genetic counselling and selection of therapy, as well as facilitating research using a novel approach to human genetic diseases.

VEXAS syndrome is an autoinflammatory disease associated with a somatic mutation of the X-linked UBA1 gene in haematopoietic progenitor cells. This disorder was originally described as a disease affecting men, but rare cases of VEXAS syndrome in women have since been reported. The theoretical existence of phenotypic sex differences in this X-linked disease is debated. We compared the features of VEXAS syndrome between males and females to better understand this disorder and to improve its diagnostic accuracy in females.

Disease-modifying drugs have transformed the treatment options for many systemic autoimmune diseases. However, an evolving understanding of disease mechanisms, which might vary between individuals, is paving the way for the development of novel agents that operate in a patient-tailored manner through immunophenotypic regulation of disease-relevant cells and the microenvironment of affected tissue domains. Immunoengineering is a field that is focused on the application of engineering principles to the modulation of the immune system, and it could enable future personalized and immunoregulatory therapies for rheumatic diseases. An important aspect of immunoengineering is the harnessing of material chemistries to design technologies that span immunologically relevant length scales, to enhance or suppress immune responses by re-balancing effector and regulatory mechanisms in innate or adaptive immunity and rescue abnormalities underlying pathogenic inflammation. These materials are endowed with physicochemical properties that enable features such as localization in immune cells and organs, sustained delivery of immunoregulatory agents, and mimicry of key functions of lymphoid tissue. Immunoengineering applications already exist for disease management, and there is potential for this new discipline to improve disease modification in rheumatology.