Congenital cystic adenomatoid malformation of the lung: diagnosis in a preadolescent

Abstract

Congenital pulmonary airway malformation (CPAM) is a rare developmental lung malformation. Nowadays, most CPAMs are diagnosed prenatally, allowing optimal prenatal and immediate postnatal care. Rarely, however, CPAM may go undetected in asymptomatic or paucisymptomatic patients, until a complication, most commonly of infectious nature, uncovers the underlying lesion. 

In this case report, a young teenage boy with a history of recurrent pneumonia presented with clinical worsening following a respiratory infection and subsequent adequate antibiotic intake. Chest radiograph revealed a left heterogeneous hypotransparency, and chest computed tomography scan disclosed exuberant cystic bronchiectasis occupying almost the entire left lower lobe. Further investigation excluded primary immunodeficiency, cystic fibrosis, and mechanical obstruction of the airway. Following the acute infectious phase, the patient underwent a programmed thoracoscopic resection of the lower lobe, that was uneventful. Macroscopic and histological examination confirmed a congenital cystic adenomatoid malformation Stocker type 1. On long-term follow-up, the patient remained asymptomatic, with normal respiratory function tests. 

Recurrent pneumonia and chronic productive cough should be actively sought in routine visits, and should prompt further investigation, including imaging targeting adequate characterization of the lung parenchyma. Despite the overall good surgical prognosis, whatever the age, early intervention, especially in asymptomatic patients at birth, may decrease surgical morbidity and other late complications related to severe and recurrent infections or even malignancy.