EC Pulmonology and Respiratory Medicine

Background: Connective tissue diseases associated Interstitial lung disease (CTD-ILD) is commonly observed in systemic sclerosis, polymyositis/dermatomyositis and rheumatoid arthritis patients and is a leading cause of morbidity and mortality. Very few studies have examined the demographics, clinico-radiologic and lung function features and the prevalence of various ILD patterns in patients with different connective tissue diseases (CTD).

Methods: In this prospective study, we recruited patients who were diagnosed with CTD-ILD in tertiary care teaching hospital in southern India, between January 2019 and March 2020. All clinical and laboratory data (including serology, radiology and pulmonary function tests) were obtained.

Results: A total of 138 patients with CTD-ILD were recruited, 73.9% of whom were females. The mean age was 50.4 (SD- 11.8) yrs. Most common symptoms were cough (88.4%) and breathlessness (85.5%). A total of 73.9% had joint pain, 95.1% of which was symmetrical, 20.9% had skin lesions characteristic of their CTD, 27.3 had finger clubbing and 26.8% had velcro crackles. The mean FVC and TLC were 1.64L (57.8%) and 2.70 (60.8%) and DLCO was 46.97% of predicted. The mean 6-minute walk distance was 349.3 m. Among patients with CTD-ILD, the most common CTD was UCTD (34.1%), followed by rheumatoid arthritis (30.4%). The common ILD patterns on HRCT were; NSIP (62.3%), UIP (23.9%) and OP (4.3%).

Conclusion: We have reported herewith the clinical and laboratory profile of the largest single centre Indian case series on CTD-ILD.

 Keywords: Interstitial Lung Disease (ILD); Connective Tissue Disease (CTD); Pulmonary Function Tests; Autoantibodies; Pulmonary Hypertension

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