Background: Diffuse interstitial lung disease (ILD) is an extra-articular manifestation of rheumatoid arthritis (RA) ^1,2 . The most common pattern is the usual interstitial pneumonia (UIP), conditioning a worse prognosis ³ .

Objectives: To describe epidemiological, clinical, and radiological characteristics and treatment used in a cohort of patients diagnosed with RA and ILD.

Methods: Retrospective descriptive study, including patients with a diagnosis of RA and ILD, reviewed in the Rheumatology and Pneumology consultations of the Virgen Macarena University Hospital, from 2010 to 2019. Data obtained from medical records are analyzed. SPSS statistical software is used.

Results: 26 patients were included, 18 women (69.2%). Median age at diagnosis of ILD was 62 years (53-73). Twelve patients (46.6%) used to smoke. The mean time from RA diagnosis to ILD diagnosis was 79 months (8-264). The RF was positive in 91.3% cases (21) and 87% of them (20) were ACPA positive. Fourteen patients (53.8%) had erosions and 3 (11.5%) had an associated Sjögren’s Syndrome. When ILD was diagnosed, the RA activity by DAS28PCR was moderate (3.28; 2.34-3.28) and 13 patients (54.1%) suffered from dyspnea. The mean value of FVC and DLCO in the first assessment was 84% (63-108) and 71.7% (64-86), respectively. The most frequent radiological pattern of ILD was NINE in 15 patients (57.7%), 6 of them (23.1%) had UIP and 5 (19.3%) presented other patterns. Prior to ILD diagnosis, 24 (92.3%) patients received oral glucocorticoids, 18 (69.2%) cases started treatment with c-DMARD and 11 (42.3%) of them with b-DMARD; the most widely used were methotrexate (MTX) in 17 patients (65.4%) and anti-TNFα in 10 (38.5%). After diagnosis, treatment was changed to 12 patients (46.6%); the most used DMARD was leflunomide, in 11 (42.3%), MTX was maintained in 7 patients (26.9%); the number of anti-TNFα used decreased to 4 cases (15.4%), using instead drugs such as rituximab 5 (19.2%), abatacept 3 (11.5%), baricitinib 2 (7.7%) and anti-IL6 2 (7, 7%). During follow-up, 11 cases (57.9%) remained radiologically stable. A slight deterioration in DLCO was observed (66%; 51-80) and there was one death due to lung disease (UIP).

Conclusion: In this study, the most frequent radiological pattern was NINE. Half of the patients used to smoke. At the diagnosis of ILD (at ILD diagnosis), dyspnea was the most relevant clinical symptom, with a slight deterioration in the? respiratory function tests. This represented a change in the therapeutic strategy.

REFERENCES:

[1]Olson AL, Swigris JJ, Sprunger DB, et al. Rheumatoid arthritis-interstitial lung disease-associated mortality. Am J Respir Crit Care Med. 2011;183:372-78.

[2]Fragoulis GE, Nikiphorou E, Larsen J, Korsten P and Conway R. Methotrexate-Associated Pneumonitis and Rheumatoid Arthritis-Interstitial Lung Disease: Current Concepts for the Diagnosis and Treatment. Front. Med. 2019;6:238.

[3]Tanaka N, Kim JS, Newell JD, et al. Rheumatoid arthritis-related lung diseases: CT findings. Radiology. 2004;232:81-91.

Disclosure of Interests: None declared