Additional information garnered from patient's file reinforces diagnosis of IUAPA:

• hypoplastic right lung with severely decreased ventilation and no perfusion, discovered incidentally on a V/Q scan performed at toddlerhood due to suspicion of foreign body aspiration
• findings at report for chest CT performed at age 5 very similar to above exam
• transthoracic echocardiography at age 8 demonstrated no cardiac anomaly
• patient's mother mentions mediastinal shift to right on chest x-ray taken at age 4 months

Differential diagnosis of a small lung on plain film includes:

• hypogenetic lung syndrome (scimitar syndrome)
• (isolated) unilateral pulmonary artery interruption/atresia/absence
• Swyer-James-MacLeod syndrome
• post-lobectomy