Difficulties in diagnosis of systemic sclerosis-related interstitial lung disease.

We discuss a case that demonstrates the difficulties in making a confident diagnosis of interstitial lung disease (ILD) associated with systemic sclerosis (SSc). Atypical symptoms can be present, suggesting the diagnosis of an underlying connective tissue disease (CTD), but it can take several years before a definite diagnosis can be made because there are insufficient features to fulfill the preset classification criteria (American College of Rheumatology criteria) for a definite underlying CTD. Close follow-up of these patients is necessary because patients with SSc-ILD have a poorer prognosis than those with SSc without pulmonary involvement. Treatment choice also differs between idiopathic ILD and SSc-related ILD.