FRI0039 LUNG ULTRASOUND UTILITY IN INTERSTITIAL LUNG DISEASE DETECTION IN RHEUMATOID ARTHRITIS
Authors: F. Godoy-Navarrete, F. G. Jiménez-Núñez, N. Mena-Vázquez, C. M. Romero-Barco, G. Diaz Cordoves, A. Fernandez-Nebro
Journal: Annals of the Rheumatic Diseases (2020)

Background: Objectives: To analyze the diagnostic utility of lung ultrasound (US) to detect interstitial lung disease (ILD) in Rheumatoid arthritis (RA) patients comparing with high-resolution computed tomography (HRCT). Methods: Study design: We performed a cross-sectional, observational study in patients with RA-ILD (cases) controlled with a gruop of RA patients without ILD (controls) paired by sex, age and time of disease evolution. Protocol: Patients were selected between May and September 2019. Patients were interwied by two rheumathologist for the protocolized collection of clinical data. The patients were assessed using HRCT, Pulmonary Function Test (PFT) and lung US.. The rheumatology who performed the lung US were blinded to patients clinical data. Variables: (1) B-lines number; (2) evaluation of the lung- ultrasound score already described: L. Gargani, Gutiérrez comprehensivo, Gutiérrez reducido and Mohhammadi;(3)pleural irregularities; (4) A pattern US lost;(5). Other variables included demographic, clinical-analytical, therapeutic and ILD-type description. Statistical analysis: descriptive, bivariant analysis. We applied Pearson’s correlation coefficient between B-lines, PFT and clinical variable.Furthermore, to establish the cut-off point of the US B-lines number for detecting the presence of significant AR-ILD in relation to HRCT, we used the receiver operating characteristic (ROC) curve analysis. A logistic regression analysis was performed to identify the intercostal spaces (IV: B-lines number in each space) wich were independently associated with ILD (DV: ILD in HRCT). Results: 71 patients were included, 37 (52,1%) with ILD-RA and 34 (47,95) RA controls. The main characteristics are shown in Table 1. RA-ILD presented more B-lines number than control without ILD (median ICR] 91.0 [31.0-149.0] vs 6.5 [1.5-30.5]; p=&lt;0.001) and more pleural irregularities (PI) [PI-median(ICR) 41.0 (5.0-57.5) vs 2.5 (0.0-7.2); p&lt;0,001]. Furthermore, RA-ILD showed a negative correlation between B-lines and DLCO(r =-0.337, p=0.048)and positive with DAS28 (r =0.347, p=0.035). Regarding US score, we found that the detection of 32.5 B-lines in 72 intercostal spaces, had a Sensitivity of 75.7%, Specifity=79.4% , PPV= 80% and NPV=75%,whilst in reduced score of 10 intercostal spaces, the detection of 5.5 B-lines had a sensivity= 62.2%,Specifity= 91.3%, PPV=88.4%, NPV=69.5%. In multivariate analysis, the intercostal spaces which showed independent association with ILD were 3 rd right anterior axillary space(OR [IC 95%] 19.0 [1.3-27.5]), 8 th right posterior axillary space (OR [IC 95%] 0.04 [0.0-0.6]), 8 th right subescapular space (OR [IC 95%] 16.5 [1.8-45.5]),9 th right paravertebral space (OR [IC 95%] 7.11 [1.0-37.1]) and 2 nd left clavicular middle space(OR [IC 95%] 21.9 [1,26-37.8]). Conclusion: Lung Ultrasoud could be a useful tool for interstitial lung disease diagnosis associated with Rheumatoid Artrithis. A 10 space reduced score showed a similar total predictive capacity than 72-space score References: Disclosure of Interests: None declared