Background:Pemphigus vulgaris belongs to a group of rare, autoimmune, blistering disorders, requiring intensive immunosuppressive therapy. Lung infections are common in patients with pemphigus vulgaris.Objective:To evaluate pulmonary function in patients with pemphigus vulgaris, in order to detect possible factors that might predispose PV patients to lung damage.Methods:Ten patients first diagnosed with severe pemphigus vulgaris and 10 healthy individuals,were included in the study. Pulmonary function testing, blood gas analysis and quantification of α1-antitrypsin serum levels were performed.Results:Mild reduction of CO diffusing capacity was recorded, compared to the mean predicted normal value. DLCOSB (single-breath carbon monoxide diffusing capacity test) values did not significantly differ between patients with pemphigus vulgaris and healthy controls, while differences regarding DLCO/VA (VA: Alveolar Volume) were statistically significant. Alpha 1-antitrypsin serum levels were decreased (<2.0g/L) in 60% (6/10) of patients with pemphigus vulgaris and were found normal in none of the healthy controls.Conclusion:A mild reduction of pulmonary diffusing capacity was observed in patients with pemphigus vulgaris.