Interstitial pneumonia vs. hypersensitivity pneumonitis with autoimmune features

Abstract

Diagnostic criteria of interstitial pneumonia with autoimmune features (IPAF) should be used to identify cases with idiopathic interstitial pneumonia (IIP) and features suggestive of connective tissue disease. Autoimmune feautures were observed in hypersensitivity pneumonitis (HP) patients as well. Patients who underwent BAL as part of diagnostic process of suspected ILD were enrolled in the study. Medical records of patients diagnosed IIP and HP were sought for autoimmune features (AF)(diagnostic criteria - An official ERS/ATS research statement: IPAF applied). Patients´ basic demographic data, BAL fluid cell counts, lung functions, serum IgG concentrations and autoimmune serology (ANA, RF, aCCP, dsDNA, ENA, ANCA) were recorded. Student t-test was used to compare demographic data in IPAF and HPAF group, frequency comparisson was used to compare serology data in both groups. In the group of 2376 patients HP was diagnosed in 257 cases, 50 were found to have AF. IIP was diagnosed in 181 patients, in 46 cases with AF. Patients diagnosed HPAF were younger (58,7±14,6) vs IPAF patients (68,4±8,81) ( P Ten years single center experience showed lower incidence of autoimmune features in HP than in IIP. Eventhough we found differences in demographics and BAL fluid cell counts, representing more probably common characteristics of HP and IIP patients, no difference in autoimmune serology was observed between the groups.