Interstitial Lung Disease and Rheumatoid Arthritis: A Review

Interstitial lung diseases (ILDs) are a group of diffuse parenchymal lung disorders that are classified according to different clinical, radiological and histopathological features. Interstitial lung disease can be primary or it can be due to a secondary cause, such as an underlying connective tissue disease (CTD). Rheumatoid arthritis (RA) is the most common CTD, and ILD can be found in a quarter of RA patients. Interstitial lung disease has a significant impact on RA patients in terms of their burden of disease and quality of life. Despite this it remains largely understudied and pathogenesis is unclear. Newer imaging techniques include ultrasound and 18F-FDG PET/CT. Therapeutics that show promise include mycophenolate mofetil and rituximab. Paradoxically, some of the agents that are good in treating articular manifestations in RA patients can result in the worsening or development of ILD.