RT Journal Article SR Electronic T1 Clinical significance of autoantibody screening in patients with idiopathic pulmonary fibrosis JF European Respiratory Journal JO Eur Respir J FD European Respiratory Society SP P2339 VO 42 IS Suppl 57 A1 Morven E.M. Wilkie A1 James D. Chalmers A1 Robin P. Smith A1 Stuart Schembri YR 2013 UL http://erj.ersjournals.com/content/42/Suppl_57/P2339.abstract AB IntroductionAutoantibody screening is frequently performed in patients with idiopathic pulmonary fibrosis (IPF), but the clinical relevance of positive autoantibodies without clinically objective connective tissue disease is unclear.MethodsA retrospective analysis was made of 114 patients with IPF. Data was collected on all autoimmune tests performed. Patients were followed up for 3 years or until death.ResultsMedian age was 72 years (interquartile range 65-77). 61.4% male. 42 had positive autoantibody testing (36.8%). Antinuclear antibody (ANA) was positive in 28.9%. 11 patients had positive antineutrophil cytoplasmic antibody (ANCA). 6 patients had positive rheumatoid factor and 1 had positive cyclic citrullinated peptide test.Comparing patients with positive tests and those without, positive autoantibodies were more frequently seen in females (64.8% vs 31.1%,p=0.01). Patients with positive autoantibodies were of similar age (median age 73 years IQR 67-77 vs median 69 years 62-78,p=0.3).Using the GAP index, a validated prognostic tool in IPF, the severity of lung disease was greater in the autoantibody positive group-mean score 3.7 SD 1.4 in the positives and 3.1 SD 1.5 in the negatives, p=0.048.Mortality rate was 31% in the autoantibody positive group and 13.9% in the negative group. Adjusting for baseline difference in severity between the groups, positivity was not associated with increased mortality (adjusted odds ratio 1.63 95% CI 0.53-5.03,p=0.4).Conclusion In our cohort, positive autoantibodies are common in IPF and are more common in female patients with more severe disease. However, positive autoantibodies do not appear to be an independent predictor of poor outcome.