Clinico-radiological profile of connective tissue disease related-interstitial lung diseases from a tertiary care centre of India: a cross sectional study.

Interstitial lung diseases (ILDs) are a frequently occurring pulmonary manifestation in patients of connective tissue diseases (CTD). Detailed understanding of this subset of lung diseases is vital, hence the study was conducted to analyze the clinico-radiological characteristics of CTD-ILD. The present study was conducted between March 2017 to February 2018 at a tertiary care teaching hospital from western India. A total of 100 patients having respiratory symptoms suggestive of ILD, who were either diagnosed cases of CTD or had clinical manifestations of underlying CTD, were included in the study.  27% of patients belonged to age group 41-50 years and 78% were females. Chief respiratory complaints were dyspnea and cough. Clubbing was present in 29% patients. The most common CTDs were rheumatoid arthritis [RA] (26%), systemic sclerosis [SSC] (21%), mixed connective tissue disorder [MCTD] (19%) and Sjogren's syndrome [SS] (16%). Restrictive defect on spirometry was seen in 58% cases and was most significant among patients with RA (65%) and SS (62%). Pulmonary arterial hypertension was seen in 40% cases and was most evident in MCTD (78%) and SSC patients (58%). Chest radiograph was normal in 47% of subjects. Most common radiological pattern on high resolution computed tomography (HRCT) thorax was non-specific interstitial pneumonia (42%) followed by usual interstitial pneumonia (21%). ILD is a common manifestation of CTD. Work-up for an underlying CTD should be offered to all ILD patients and vice versa.