Standardized 3D-CT lung volumes for patients with acute exacerbation of rheumatoid arthritis-associated interstitial lung disease.

OBJECTIVES: Fibrotic interstitial lung disease (ILD) is a progressive lung disease characterized by loss of lung volume, resulting in a leading cause of death in patients with RA. Crucially, acute exacerbation (AE) of ILD shows higher morbidity and mortality with rapid deterioration of the lungs. However, a quantitative assessment for physiological changes at AE has yet to be performed. This study hypothesized that quantitative assessments of lung volume (LV) accurately indicate disease severity and mortality risk in patients with AE-RA-ILD. METHODS: This multicentre cohorts study quantitatively assessed physiological changes of RA-ILD at diagnosis (n = 54), at AE (discovery-cohorts; n = 20, and validation-cohort; n = 33), and controls (n = 35) using 3D CT (3D-CT) images. LV was quantitatively measured using 3D-CT and standardized by predicted forced vital capacity. RESULTS: Patients with RA-ILD at diagnosis showed decreased LV, predominantly in lower lobes, compared with controls. Further substantial volume loss was found in upper- and lower lobes at AE compared with those at diagnosis. During AE, decreased standardized 3D-CT LV was associated with a worse prognosis in both cohorts. Subsequently, standardized 3D-CT LV was identified as a significant prognostic factor independent of age, sex and the presence of UIP pattern on CT by multivariate analyses. Notably, a composite model of age and standardized 3D-CT LV successfully classified mortality risk in patients with AE-RA-ILD. CONCLUSION: Volume loss at AE in patients with RA-ILD was associated with increased mortality. Assessing physiological change using standardized 3D-CT might help evaluate disease severity and mortality risk in patients with AE-RA-ILD.

Successful treatment of rheumatoid arthritis-associated interstitial lung disease with filgotinib: A case report on janus kinase 1 inhibition.

Filgotinib, a janus kinase 1 (JAK1) inhibitor, is used in the treatment of rheumatoid arthritis (RA). RA-associated interstitial lung disease (RA-ILD) is a severe RA complication with no established effective treatment. We report the case of a patient with RA-ILD successfully treated with filgotinib. A 46-year-old woman with RA and RA-ILD, presenting with a non-specific interstitial pneumonia pattern, was refractory to abatacept and prednisolone but responded to filgotinib. Both arthritis and RA-ILD improved significantly, and the patient remained in remission for over 12 months. Basic research indicates that JAK1 plays a role in the cytokine signal transduction in ILD; however, there are no clinical reports on the efficacy of filgotinib in RA-ILD. This case suggests filgotinib as a potential treatment for patients with RA-ILD, particularly in the early stages of this disease.