SERPINA1 and cystic disease of lung: These radiological findings are consistent with diagnosis of Williams-Campbell syndrome, which was diagnosed after ruling out the other common causes of bronchiectasis.<h4>Conclusion</h4>Williams-Campbell syndrome is a rare congenital cystic lung disease, the diagnosis of which is made by exclusion of common causes of bronchiectasis such as cystic fibrosis, allergic bronchopulmonary aspergillosis, tuberculosis, dyskinetic cilia syndrome and alpha-1 antitrypsin deficiency.