Interstitial Lung Disease, ILD and Connective Tissue Disease Signs of Connective Tissue DiseasePatients with connective tissue diseases frequently have symptoms of interstitial lung disease, and in some cases, the pulmonary symptoms may precede extrathoracic symptoms by months or even years.17 A diagnosis of IPF requires exclusion of other causes of lung disease, so it is imperative to evaluate patients for radiographic evidence of these connective tissue diseases.45