Prenatal course and postnatal management of peripheral bronchial atresia: association with congenital cystic adenomatoid malformation of the lung.

Objective: Peripheral bronchial atresia (PBA), a newly identified fetal lung lesion, is often asymptomatic and managed nonoperatively. However, recent studies suggest that bronchial atresia plays a role in the etiology of microcystic maldevelopment present in congenital cystic adenomatoid malformations (CCAM) which require resection to decrease the risk of infection, pneumothorax and malignant degeneration. The purpose of this study was to evaluate the prenatal radiographic and postnatal computed tomography (CT) scan/pathology findings with attention to the pathologic diagnosis of microcystic maldevelopment in infants with the presumptive diagnosis of PBA.

Methods: A retrospective review of prenatal and postnatal records of patients diagnosed with fetal lung lesions was performed. Two groups of patients were identified: (1) patients diagnosed with PBA on postnatal CT scan (n = 16), and (2) patients with the pathologically confirmed diagnosis of PBA independent of postnatal CT findings (n = 23).

Results: Prenatal ultrasound diagnosis of these lesions included CCAMs, hybrid lesions, bronchopulmonary sequestrations and bronchial atresia. Eleven of the 16 patients in group 1 with the postnatal radiologic diagnosis of PBA underwent surgical resection, 6 of which were found to have microcystic changes consistent with CCAM. Evaluation of the 23 patients in group 2 with pathologically confirmed PBA identified 65% that had evidence of microcystic maldevelopment consistent with the small cyst type of CCAM.

Conclusion: Radiographically diagnosed PBA as well as pathologically confirmed PBA is frequently associated with microcystic changes consistent with the small cyst type of CCAM. Thus, operative management should be considered for PBA to decrease CCAM-associated risks.