Rheumatoid Arthritis-Associated Interstitial Pneumonia Refractory to Initial Therapy: Successful Control Through Combined Anti-Inflammatory, Antifibrotic and JAK-STAT-Targeted Treatment.

Connective tissue disease (CTD)-associated interstitial lung disease (ILD) accounts for a significant proportion of ILD cases, with rheumatoid arthritis (RA) being one of the most common underlying disorders. Although immunosuppressive therapy plays a central role in CTD-ILD, its efficacy is limited in fibrotic ILDs, particularly those with a usual interstitial pneumonia (UIP) pattern. We report a case of RA-associated ILD in an elderly woman who experienced acute disease progression despite ongoing treatment. A multimodal approach combining corticosteroids, tacrolimus, antifibrotic therapy (nintedanib) and the Janus kinase (JAK) inhibitor baricitinib led to marked clinical, radiological and biomarker improvement. This case underscores the potential benefit of a multi-target strategy addressing both inflammation and fibrosis and suggests a possible role for JAK inhibition in refractory RA-ILD.