Congenital Pulmonary Airway Malformation (CPAM)

Michael P. D'Alessandro, M.D.
Peer Review Status: Internally Peer Reviewed

Etiology/Pathophysiology:
Congenital hamartomatous lesion of the lung.

Pathology:
There are 3 subtypes, all of which lack normal bronchial communications:

Type I - multiple large air or fluid filled cysts, usually greater than 2.0 cm in diameter .

Type II - variably sized less bulky lesion with smaller cysts .

Type III - bulky mass composed of multiple tiny, microscopic cysts resembling bronchi that involves the entire lobe . Adenomatous hyperplasia with an increase in terminal bronchiolar structures, as well as a polypoid arrangement of mucosal epithelium is seen.

Imaging Findings:
Seen with equal frequency in any lobe. Can rarely be bilateral .

Type I - multiple large air or fluid filled cysts that produces a mediastinal shift and compression of adjacent lung. The most common type is Type I. It may have air fluid levels in its cysts. If infected, it may appear homogeneously opacified.

Type II - variable sized less bulky lesion with smaller cysts with less mediastinal shift and respiratory distress.

Type III - bulky radiographically solid mass composed of multiple tiny cysts that involves the entire lobe.

DDX:

• Diaphragmatic hernia - unlike a CAM which has its abdominal organs in a normal position, the diaphragmatic hernia has its abdominal organs in the chest.
• Congenital lobar emphysema
• Sequestration
• Post infectious pneumatocele
• Foreign body, trachea - in an older child.

References:

• Correlapedia
• Thoracopedia
• Thoracopedia
• Thoracopedia

Section Top | Title Page

URL: http://www.virtualpediatrichospital.org/