Interstitial Lung Diseases Associated with Connective Tissue Pathologies: Radiologic Features

Introduction: The high resolution computed tomography (HRCT) is an important part in the diagnostic approach of interstitial lung disease (ILD) associated with connective tissue diseases (CTD) by providing detailed information on the elementary lesion and the radiological pattern of ILD. Aim: to point out the role of HRCT in the diagnosis of ILD associated with CTD (ILD-CTD). Methods: A Retrospective descriptive study was conducted between 2008 and 2017. Data of 24 patients presenting ILD-CTD were collected. A review of HRCT was performed by a radiologist without knowledge of the CTD. Results: Predominant elementary lesion of ILD associated with dermatomyositis (9 cases) was ground glass opacity (n = 9) followed by consolidation (n = 6). Non Specific Interstitial Pneumonia (NSIP) was the most reported pattern (5 cases). Ground glass opacity was also the predominant elementary lesion for the 2 cases of scleroderma and in Sjögren’s syndrome (4 cases/5). NSIP was the predominant radiological presentation in these two CTD. Lymphoid interstitial pneumonia revealed Sjögren’s syndrome in one case. In rheumatoid arthritis (6 cases), the elementary HRCT lesions were irregular interlobular septal thickening (n = 4) and honeycombing (n = 4) consistent with Usual Interstitial Pneumonia (UIP) in 2 cases. Similarly UIP has been described for the 2 patients with lupus and mixed connective tissue disease. Conclusion: HRCT plays an important role in the management of ILD-CTD. Description of the HRCT elementary lesions and the radiological pattern of ILD can be helpful for CTD’s diagnosis.