Usefulness of Lung Ultrasound as a Method for Early Diagnosis of Interstitial Lung Disease in Patients with Rheumatoid Arthritis

Abstract

Purpose

To determine the value of lung ultrasound (LUS) compared to high-resolution computed tomography (HRCT) in the early diagnosis of interstitial lung disease (ILD) in patients with rheumatoid arthritis (RA).

Patients and Methods

An observational prospective study was performed. Were included patients with respiratory symptoms or/and, patients with crackles in auscultation during medical consultation. All patients underwent to chest X-rays, LUS, HRCT,and respiratory function tests.

Results

A total of 192 patients with RA were included. Mean disease duration was 16.8 ± 11.1 years. 72% were positive for rheumatoid factor or anti-citrullinated antibodies. Of the total number of subjects, 54.7% had respiratory symptoms. The other patients did not have respiratory symptoms, but they did have had crackles on pulmonary auscultation. B lines > 11.5 on the ROC curve predicted ILD (AUC 0.63; CI 95%: 0.55–0.71; p < 0.003). A DLCO value of <7.13 significantly predicted the presence of ILD (AUC 0.61; 95% CI: 0.52–0.70; p < 0.028).

Conclusion

The findings of this study suggest that LUS is a valuable tool for the early diagnosis of ILD in patients with RA, and together with DLCO, can adequately predict the presence of ILD in this population. LUS also helps to determine which patients with respiratory symptoms and signs suggestive for ILD are undergo to HRCT.

Keywords:

• rheumatoid arthritis
• interstitial lung diseases
• respiratory function tests

Acknowledgments

The authors would like to thank Fernando Rodríguez-Florido, who help in the figure design.

Disclosure

Dr Pedro Santos-Moreno reports grants, personal fees from Bristol, personal fees, non-financial support from Abbvie, personal fees, non-financial support from Janssen, personal fees, non-financial support from Pfizer, personal fees, non-financial support from Biopas – UCB. Dr Adriana Rojas-Villarraga reports grants from Asociación Colombiana de Reumatología, Fees for conferences from Amgen Fees for conferences and advisory board from Janssen, Fees for conferences from Pfizer, outside the submitted work. The authors report no other conflicts of interest in this work.