Interstitial lung disease (ILD) induces overwhelming morbidity and kills more patients with connective tissue disease (CTD) than any other CTD-related manifestation.1–5 Because of this, there is a keen and growing interest in the rheumatology and pulmonary communities to identify prognostic variables for CTD-associated ILD (CTD-ILD). Treatment options for patients with ILD, idiopathic as well as those associated with CTD-ILD are limited. Determining prognosis is important, especially when considering therapeutic options such as lung transplantation as well as monitoring response to therapy.

High-resolution CT (HRCT) plays a central role in the diagnostic evaluation of patients with ILDs.6 Furthermore, features such as honeycombing and severity of fibrosis can both serve as diagnostic surrogates for surgical lung biopsy as well as predict the risk of subsequent mortality for patients with idiopathic interstitial pneumonias (IIP).7–9 Less is published regarding the prognostic characteristics of features seen on HRCT in patients with CTD-ILD; diseases that often have a better prognosis compared with patients with IIP10 ,11 and where surgical lung biopsy is less often performed.

Walsh et al12 evaluated the ability of radiographic and pulmonary function characteristics to predict subsequent prognosis in patients with CTD-ILD. They included a relatively large and diverse study population consisting of 168 patients with a variety of CTDs such as rheumatoid arthritis (n=39), systemic sclerosis (SSc) (n=32), mixed CTD (n=33), polymositis (n=33), systemic lupus erythematosus (n=17) and Sjogren's disease (n=14). Fifty-one patients had surgical lung biopsy available for evaluation.

The …