Alpha-1-antitrypsin deficiency is often diagnosed in middle aged patients with early onset lower lobe predominant emphysema and accompanying bronchiectasis. Early on the disease is asymptomatic and often not detected. This is a nice case showing the appearance of the disease in a young patient, with no apparent changes on plain radiograph. The important CT features of the case are:

• lack of walls/ cysts, hence this is not cystic lung disease
• destruction of airspaces with a lower lobe predominance and preservation of underlying vessels and connective tissue stroma
• bilateral lower lobe bronchiectasis.

The diagnosis was proven via genotyping.