Spontaneous pneumothorax as the initial presentation of congenital pulmonary airway malformation in a teenager without prior symptoms

Congenital Pulmonary Airway Malformation (CPAM) is a rare developmental lung anomaly, usually diagnosed prenatally but often asymptomatic until early childhood. It can present with respiratory distress, recurrent infections, or rarely, spontaneous pneumothorax (PTX). We report a 15-year-old female who presented with spontaneous PTX. After chest tube placement and lung re-expansion, imaging revealed an 8 cm cystic lesion in the left lower lobe, which was surgically resected. Histopathology confirmed CPAM type 1. While PTX in adolescents is typically due to primary spontaneous causes, infection, or trauma, this case highlights the need to consider congenital anomalies like CPAM in the differential diagnosis, especially in patients without neoplastic or vascular risk factors.