Pulmonary Complications in Connective Tissue Disease-Associated Interstitial Lung Disease

Interstitial lung disease (ILD) associated with connective tissue disease (CTD) is a challenging entity burdened with multiple risk factors and undesirable events. ILD can occur at any time and progress regardless of the underlying disease activity. Apart from the established difficulties in choosing an appropriate treatment strategy for both pulmonary and extrapulmonary involvement, such patients require a holistic and multidisciplinary approach. In an attempt to emphasize the significance of the problem and suggest potential research directions, the authors present four potentially most important and often misdiagnosed complications of the CTD-associated ILD, in the form of acute exacerbation, drug-induced pulmonary toxicity, nonspecific infection, and tuberculosis. Similar clinical manifestations of the patient's progressive deterioration, as well as the complex etiology of pulmonary involvement, raise controversies and force difficult therapeutic decisions. High morbidity and mortality among patients with progressive CTD-associated ILDs necessitate further research in an attempt to enhance the treatment management in each CTD and improve the patients' quality of life.