Diffuse Cystic Lung Diseases.

Diffuse cystic lung diseases (DCLDs) are a group of diverse pulmonary disorders with varying pathophysiology that are characterized by the presence of thin-walled, air-filled spaces within lung parenchyma. High-resolution computed tomography plays a crucial role in the evaluation of DCLDs, and cyst characteristics such as morphology, distribution, and the presence of other associated radiologic findings can help distinguish between different DCLDs. DCLDs can be classified according to their underlying pathophysiology as neoplastic, genetic, lymphoproliferative, infectious, associated with other forms of interstitial lung disease, or related to smoking. In this review we will provide a clinical overview on the most common DCLDs that are encountered in clinical practice: lymphangioleiomyomatosis, pulmonary Langerhans cell histiocytosis, Birt-Hogg-Dubé syndrome, and lymphoid interstitial pneumonia/follicular bronchiolitis, with a focus on practical aspects that can help clinicians in the optimal diagnosis and management of patients with DCLDs.