Rheumatoid Arthritis and Associated Pathologies of the Respiratory System (Literature review)

The objective: to analyze the frequency of respiratory pathologies associated with rheumatoid arthritis (RA), their structure and diagnostic approaches. Materials and methods. In order to achieve the task, a detailed analysis of scientific articles on the topic of respiratory system pathologies in patients with RA was conducted in journals indexed in the SCOPUS, Web of Science, MEDLINE, Google Scholar, UpToDate, ResearchGate databases. The search in scientometric databases was conducted using the following keywords: “Rheumatoid arthritis”, “Shared epitope”, “Interstitial lung disease”, “Bronchiectasis”, “Bronchiolitis”, “Cricoarytenoid arthritis”, “Common interstitial pneumonia”, “Nonspecific interstitial pneumonia”, “Pleurisy”, “Pleural effusion”, “Follicular bronchiolitis”, “Constrictive bronchiolitis”, “Rheumatoid lung nodules”, “Pulmonary vasculitis”. Results. RA is an autoimmune pathology that primarily affects the musculoskeletal system, but the presence of extra-articular manifestations often indicates a more severe course and requires a balanced approach to the treatment of this category of patients. The incidence of RA in Europe is 0.5–1%, with the involvement of the respiratory system in the pathological process, which occurs in 30–40% of cases, contributing to a significant increase in mortality. Clinical manifestations of respiratory damage in RA may be mild or even absent, so the issue of managing these pathologies in the context of patients with RA currently remains open. This literature review highlights current information on the involvement of the respiratory system in patients with RA. The most common pathologies of the respiratory system are interstitial lung disease (ILD), which is associated with RA (RA-ILD) – 19–66%, cricoarytenoiditis – 54–72% and pleural effusion / pleurisy – up to 70%. Less common pathologies are bronchiolitis and bronchiectasis – up to 30% both, and the frequency of pulmonary rheumatoid nodules, pulmonary vasculitis and drug toxicity varies within 1%. Firstly, the patterns of ILD and their frequency have been described: usual interstitial pneumonia (6–66%), nonspecific interstitial pneumonia (14–57%), organizing pneumonia (0–11%), and diffuse alveolar damage, acute interstitial pneumonia and bronchiolitis obliterate are much rarer cases. RAILD has been actively studied in recent years and is associated with damage to the airways, pulmonary vascular system and pleura in the patients with RA. High-resolution computed tomography (HRCT) and functional respiratory tests (FRT) are the preferred methods for RA-ILD diagnosis, and ultrasound-guided thoracocentesis with subsequent pleural fluid analysis is the first-line method for determining pleural involvement. It is important to note that smoking, older age, male gender, high antibody levels and high RA activity, as well as drug toxicity to the lungs in combination with genetic factors are leading risk factors for developing ILD, which makes it possible to influence these modifiable factors through non-drug and drug therapy. In addition to RA-associated pathologies, chronic obstructive pulmonary disease (COPD) can be detected in half of patients, the course of which is complicated by RA, which makes the process of differential diagnosis quite difficult. Conclusions. RA can be characterized not only as pathology of the musculoskeletal system, but also a disease that simultaneously affects other body systems. Although the damage to the respiratory system in RA can be 30–40%, its impact on the quality of life of patients and the prognosis is quite significant. Analysis of modern scientific publications provides an idea not only of the frequency of respiratory system lesions in RA, but also determines the structure of these pathologies: the most frequently diagnosed are 2 patterns of RA-ILD (common and nonspecific interstitial pneumonia), cricoarytenoiditis and pleural effusion/pleurisy associated with RA, as well as COPD; less frequent are lesions of the large and small caliber respiratory tracts, and the rarest conditions are rheumatoid pulmonary nodules, rheumatoid pulmonary vasculitis and iatrogenic effects of drugs. HRCT and FRT allow us to diagnose most pathologies of the respiratory system in RA, however, in the case of pleural effusion/pleurisy, thoracocentesis with pleural fluid analysis is the first choice. Understanding the features of lesions of the respiratory system in patients with RA will allow us to outline an approach to diagnosing these conditions in order to create an individual treatment plan for this category of patients.