Adult-onset Still's disease (AOSD) is an uncommon inflammatory condition of unknown origin and pathogenesis. Pulmonary involvement is rare and includes pleural effusion and transient pulmonary infiltrates. We describe and discuss difficulties in the diagnosis of severe respiratory symptoms with uncommon radiological and histological findings and serious prognostic implication in a 24-year-old woman with a severe form of AOSD with destructive arthritis and hematological complications.