A tall, thin teenager with no past medical history presents to an urgent care clinic in acute respiratory distress. They report playing video games when they suddenly experienced right-sided chest pain and shortness of breath. Physical exam is notable for respiratory rate 35 breaths per minute, absent breath sounds on the right upper side of the chest wall on auscultation, and hyperresonance on percussion over the right upper lobe. With palpation, there is absent fremitus over the right upper lobe. What diagnosis best describes these findings?

A. Pneumonia is incorrect because pneumonia typically presents with fever, productive cough, and crackles on auscultation, along with dullness to percussion and increased fremitus due to lung consolidation. This patient instead has hyperresonance and absent breath sounds, which are not consistent with pneumonia. B. Asthma exacerbation is incorrect because asthma presents with diffuse wheezing, prolonged expiration, and increased work of breathing. Breath sounds are usually present but diminished with wheezing, not completely absent in one localized area. Hyperresonance may occur, but localized absent breath sounds and absent fremitus point away from asthma. C. Spontaneous pneumothorax is correct because the patient has classic findings: sudden onset chest pain and dyspnea, especially in a tall, thin adolescent, along with absent breath sounds, hyperresonance on percussion, and decreased or absent tactile fremitus on the affected side. These findings occur due to air accumulation in the pleural space, which collapses the lung and prevents normal sound transmission. D. Pericarditis is incorrect because it presents with sharp chest pain that improves when leaning forward and may include a pericardial friction rub on auscultation. It does not cause unilateral absent breath sounds, hyperresonance, or absent fremitus.