Pulmonary Sequestration in the Guise of Pneumonia: Clues to a Hidden Entity.

Pulmonary sequestration is an important yet often overlooked congenital lung malformation in adolescent medicine characterized by dysplastic, non-functioning pulmonary tissue that lacks communication with the tracheobronchial tree and derives its blood supply from an anomalous systemic artery. We report the case of a 12-year-old female patient referred to our institute with a six-month history of intermittent fever, cough, and chest pain, initially managed as a case of right-sided pneumonia elsewhere. Contrast-enhanced computed tomography of the thorax revealed a cavitary soft tissue lesion in the right lower lobe supplied by a systemic artery arising from the descending thoracic aorta with pulmonary venous drainage and no bronchial communication, establishing the diagnosis of intralobar pulmonary sequestration. Surgical resection was performed, and histopathological examination demonstrated cystically dilated bronchi and bronchioles with chronic inflammation, fibrosis, bronchiolization, and thick-walled systemic-type arteries, confirming the diagnosis. This case emphasizes the importance of considering pulmonary sequestration in patients with recurrent lower lobe infections and highlights the integrated role of imaging, histopathology, and pediatric surgical management in establishing the diagnosis, guiding definitive treatment, and preventing complications.