[Pulmonary involvement in rheumatoid arthritis]

Pulmonary involvement in patients with rheumatoid arthritis, in particular interstitial lung diseases (RA-ILD) is of great clinical importance. Patients should be asked about symptoms of pulmonary involvement and the lungs should be clinically examined even during the diagnostic procedure and regularly during the course of the disease. Before initiation of a basic pharmacological treatment an X‑ray examination of thoracic organs is obligatory. In cases of conspicuous clinical or radiological findings, extended diagnostic procedures with lung function testing (body plethysmography with diffusion measurement) and high resolution computed tomography (CT) should be performed, depending on the findings. The differential diagnosis of interstitial lung alterations in patients with RA is broad and should consider side effects of the basis medication in addition to infectious causes. The optimal pharmacological treatment of RA-ILD is not sufficiently clarified. The value of methotrexate (MTX) has changed because, in contrast to previous assumptions, a better course could be observed under MTX treatment, at least in mild to moderate courses of RA-ILD. In the case of a clinically relevant RA-ILD, tumor necrosis factor (TNF) blockers should be avoided because a dramatic deterioration of pulmonary function has sometimes been observed. Among biological disease-modifying antirheumatic drugs (DMARD), rituximab and abatacept are currently preferred. The role of Janus kinase (JAK) inhibitors in RA-ILD is currently being discussed but limited data are available. Patients with RA-ILD benefit from a close collaboration between pulmonologists and rheumatologists.