In the past two decades, the management and outcomes of inflammatory rheumatic diseases (IRDs) such as rheumatoid arthritis (RA), the spondyloarthropathies, psoriatic arthritis and ankylosing spondylitis have tremendously changed to such an extent that their natural history, as described in classical textbooks, is now almost unrecognisable. The huge expansion of our therapeutic armamentarium in combination with innovative treatment strategies such as treat-to-target presently makes it possible to achieve remission in a substantial proportion of patients with IRDs. Therefore, joint destruction and the well-known deformities of, for instance, the hands are not frequently observed. Some ‘traditional’ extra-articular phenomena such as clinically overt vasculitis and complications such as cervical spine subluxation have become very rare. As a result, the concept of IRD management, monitoring and outcome is changing focus and is being considerably expanded. It increasingly focuses on non-articular manifestations of the primary IRDs. It encompasses multiple co-morbidities that are important to the patient’s overall well-being; present significant diagnostic, monitoring and therapeutic challenges to the managing rheumatologist; and have become the main determinant of personal, healthcare and epidemiological outcomes. It has metamorphosed from the management of almost exclusively the physical aspects of a disease to a more rounded and personalised bio-psycho-social management approach of an individual patient. In addition, it has to deal with a continuously changing landscape of potential adverse outcomes of different combinations of treatments and strategies that require different surveillance systems and preventive measures. In this issue of Best Practice & Research Clinical Rheumatology, we attempt to address some of these problems by focussing on IRDs from a different perspective, that is, involvement of other organs. In each case, experts in their respective fields outline IRD-specific manifestations related to the organ in question, discuss how the primary disease or its treatment may affect this organ and how, in turn, such involvement may affect anti-rheumatic treatment choices. There is a clear focus on the clinician; however, essential pathophysiology, open questions and a research agenda are provided. The term ‘organ’, although applicable in most chapters, is used loosely on a couple of occasions to encompass systemic disease manifestations and psychosocial constructs.

Inflammatory joint diseases might only rarely present themselves with systemic features such as fever. Fever in a patient with any type of arthritis, however, should never be underestimated irrespective of whether they receive immunomodulatory therapy or not. Considering some real-life clinical cases, a review of this problem and suggestions for a diagnostic workup is presented in chapter 1. In chapters 2 and 3, the ocular and oral manifestations, respectively, are reviewed, irrespective of whether they occur as extra-articular manifestation of the underlying IRD or as adverse events of the treatments used. Chapter 4 covers an organ system that has received a lot of attention in the last decade: the cardiovascular system. Cardiovascular risk factors, cardiovascular disease per se and their sequelae are very common in people with IRDs, and their identification, diagnosis and treatment are an important part of IRD management.

Lung involvement is a frequent but not always well recognised complication of IRDs or their treatments and is addressed in chapter 5; improvements in other co-morbidities (e.g. cardiovascular) are ‘elevating’ lung-related pathologies (including infections) towards the top position of outcome-defining co-morbidities in patients with IRDs. In chapter 6, the latest data about microbiota and the role of the gastrointestinal tract in the pathogenesis of IRDs are discussed; this very interesting field of research is soon likely to reach its translational potential into routine clinical practice. Chapter 7 discusses the interplay between the systemic inflammatory response characteristic of IRDs and major metabolic pathways. The links with other co-morbidities, particularly cardiovascular, are obvious and strategies to tackle the dysmetabolic state of patients with IRDs should form an important part of their overall management. Although the incidence of clinically overt vasculitis as an extra-articular phenomenon of RA in particular has markedly decreased, it remains a severe complication of the disease. A description of the different types of vasculitis and new treatment options are reviewed in chapter 8. Chapter 9 covers an extremely important aspect of IRDs: their psychosocial implications. Despite the fact that treatment of IRDs has markedly improved, the disease itself, the uncertainty regarding its treatment and course, the healthcare system and societal factors, amongst many others, continue to have a massive impact on an individual patient’s psychosocial functioning. Indeed, improvement of such outcomes is becoming the main target of personalised medicine. An overview of the risk factors, available psychological interventions and how they should and could be practically used in daily clinical practice is given in this chapter. Finally, because of the disease processes themselves and the more aggressive treatments and strategies, infections are becoming a major cause of morbidity and mortality in patients with IRDs. Infection prevention strategies, including systematic and timely vaccinations, should be part of routine management of IRDs, but even in well-developed health systems, they are not successfully practiced. This problem and practical guidance are reviewed in chapter 10.

There are important organ systems, such as the skin and the nervous system, which could not be covered in this issue because of practical difficulties. Even with such limitations, we hope that this special issue of Best Practice & Research Clinical Rheumatology will prove to be of great interest to practising rheumatologists and will help us all to improve our clinical practice and strategies of managing individual patients with IRDs.