E2463. Putting Holes Together to Diagnose Adult Cystic Lung Disease
  1. Sreeja Sanampudi; UT Southwestern Medical Center
  2. Kiran Batra; UT Southwestern Medical Center
Cystic diseases of the lung are almost uniformly uncommon or rare; however, when identified, careful consideration is warranted since many of the responsible etiologies have far-reaching clinical implications, particularly if left untreated. Potential causes of cystic lung disease include congenital, genetic, infectious, inflammatory, smoking, and neoplastic etiologies, which can be effectively characterized based on pulmonary and extra pulmonary imaging features, often in cohesion with clinical and pathological findings.

Educational Goals / Teaching Points
A constellation of imaging findings can be used to distinguish true pulmonary cysts from peripheral cystic airspace diseases like paraseptal emphysema, honeycombing, and bullae in addition to intraparenchymal cystic airspaces like cavity, centrilobular emphysema, blebs, and cystic bronchiectasis.

Key Anatomic/Physiologic Issues and Imaging Findings/Techniques
There is a broad spectrum of cystic lung diseases with several overlapping features making diagnosis challenging. A stepwise diagnostic approach can be utilized via imaging and, in some cases, biopsy of true cysts to identify underlying pathology. First and foremost, the cysts need to be differentiated from their mimics including cavitary lesions, centrilobular emphysema, and cystic bronchiectasis. Characterizing cysts based on solitary or multifocal distribution and associated ancillary findings (such as association with nodules, ground glass opacities) can help in distinguishing them. Various common and rare cystic lung diseases including lymphangiomyomatosis, pulmonary langerhans cell histiocytosis, Birt-Hogg-Dube syndrome, lymphocytic interstitial pneumonia/follicular bronchiolitis, and amyloidosis. A brief description of others like desquamative interstitial pneumonia, pneumocystis jirovecii infection, and tracheobronchial papillomatosis will be presented with diagnostic criteria, imaging findings, treatment, complications, and commonly seen associations with other disease processes.

A systemic, simple and effective framework for analyzing and characterizing cystic diseases of the lung based on clinical and radiological features, can be a useful aid for the clinicians in the management of cystic lung diseases.