University of Pisa, Rheumatology Unit Pisa, Pisa, Italy
Gaetano La Rocca1, Francesco Ferro2, Giovanni Fulvio3, Silvia Fonzetti4, Inmaculada Concepción Navarro García5, Elena Elefante6, Chiara Romei7, Marta Mosca6 and Chiara Baldini3, 1University of Pisa, Rheumatology Unit, Palermo, Palermo, Italy, 2Clinical and Experimental Medicine Department, Azienda Ospedaliero-Universitaria Pisana, Pisa, Pisa, Italy, 3University of Pisa, Pisa, Pisa, Italy, 4Azienda Ospedaliera Universitaria Pisana, Pisa, Italy, 5Clinical and Experimental Medicine Department, Azienda Ospedaliero-Universitaria Pisana, Pisa, Italy, 6University of Pisa, Pisa, Italy, 7University of Pisa, Rheumatology Unit, Pisa, Italy
Background/Purpose: Interstitial lung disease (ILD) is a relatively frequent manifestation of Sjögren's Syndrome (pSS), potentially presenting with a wide spectrum of clinical-radiological characteristics. Anti-Ro52 autoantibodies have been recently recognized as a risk factor for ILD in pSS. However, little is known about the relationship between circulating autoantibodies and clinical characteristics of pSS-ILD patients.
Aim of the study was: 1. to compare pSS-ILD patients with non-ILD pSS patients and 2. to investigate the impact of serology on the pulmonary phenotype of pSS-ILD patients.
Methods: This was a monocentric observational study, including pSS patients (2016 ACR/EULAR criteria) in follow-up from 2012 to 2022. Demographic, clinical, biological, and imaging data updated to last follow-up visit were collected. ILD presence for all cases was confirmed by an expert radiologist based on HRCT chest findings. She assessed HRCT patterns, ILD extension and severity by Warrick score. Anti-Ro60 and anti-Ro52 were assessed by immunoblotting. A two-step cluster analysis was performed to identify ILD subgroups using anti-Ro60 and anti-Ro52 positivity status, HRCT pattern, age at pSS diagnosis and latency from ILD onset to pSS diagnosis or viceversa. Differences in Warrick score and functional tests between the subgroups were assessed.
Results: 615 pSS patients were included. Out of them 51 (8.3%) presented ILD. Compared to non-ILD patients, pSS-ILD patients were significantly older (p< 0.0001), had a higher ESSDAI at baseline (p< 0.001) and a higher frequency of isolated anti-Ro52 antibodies (p< 0.001). Cluster analysis identified 5 subgroups in ILD patients (Fig. 1a and 1b). ILD tended to precede the diagnosis of pSS in clusters 1 and 4, whereas tended to occur during the disease course in clusters 2, 3 and 5. Clusters 1 was characterized predominantly by a seronegative status and a NSIP pattern whereas cluster 4 by isolated-Ro52 and a UIP pattern. The latter presented the most severe abnormalities in functional tests (p=0.02) and tended to present the worst Warrick score (p=0.08). Clusters 3 and 5 were both characterized by a predominant NSIP pattern, generally occurring within the first 5 years of the disease; however, cluster 3 was generally characterized by isolated anti-Ro52 whereas cluster 5 predominantly by antiRo60/anti-Ro52 positivity. Cluster 2 patients were the youngest (p< 0.001), they were anti-Ro60/Ro52 positive and presented the longest average time from pSS to ILD diagnosis (p< 0.001). All the 4 LIP cases in our cohort were included in cluster 2.
Conclusion: In this study we highlighted a significant association between pSS-ILD patients' serological profile and pulmonary phenotype in terms of clinical presentation, severity and imaging patterns. Fig 1a
Fig 1b Disclosures: G. La Rocca, None; F. Ferro, None; G. Fulvio, None; S. Fonzetti, None; I. Navarro García, None; E. Elefante, None; C. Romei, None; M. Mosca, Eli Lilly, AstraZeneca, UCB, GlaxoSmithKlein(GSK); C. Baldini, None.