Screening for Myositis Antibodies in Idiopathic Interstitial Lung Disease

International guidelines recommend screening for connective tissue disease (CTD) with autoantibodies when evaluating patients with idiopathic interstitial lung disease (ILD). Idiopathic inflammatory myositis comprises of a subgroup of CTD diagnosed with myositis antibodies (MA), often presenting with ILD. Our aim was to evaluate the utility of MA screening in patients with idiopathic ILD. A retrospective analysis was conducted on patients referred with idiopathic ILD to a tertiary centre ILD clinic who were screened for MA. Patients with known or suspected CTD were excluded. Descriptive statistics, univariate analysis and multivariable logistic regression were used to detect associations between MA and patient characteristics. Of 360 patients, 165 met inclusion criteria and 44 (26.7%) were identified to have MA. Fourteen patients (8.5%) had a change in diagnosis as a result of MA screening. Multivariable logistic regression identified the presence of MA to be associated with current smoking [OR 6.87 (1.65–28.64), p = 0.008] and a diffusing capacity of