Question 207

Question:

A previously healthy, tall, and slender 19-year-old woman has the sudden onset of right-sided chest pain followed by progressive dyspnea. Ten hours later, an x-ray of the chest shows a collapsed right lung and air in the right pleural space. Which of the following is the most likely underlying condition?

Correct Answer: E.  Subpleural blebs

Primary spontaneous pneumothorax presents with acute chest pain and shortness of breath. It is believed to result from rupture of a subpleural bleb (choice E), which is usually located in the apex of the lung. Blebs can be found in more than 75% of patients undergoing thoracoscopy for treatment of primary spontaneous pneumothorax. Also, patients with a spontaneous pneumothorax tend to be thinner and taller on average as is the case with this patient. An important distinction of the correct answer from the other answer choices is that it is the only choice that most likely will have an acute presentation in adulthood.
Bronchiectasis (choice A) and lung abscess (choice B) are both caused by infectious processes that would be unlikely in a previously healthy patient.
Panacinar emphysema (choice C) and pulmonary sequestration (choice D) would both most likely present much earlier in life. Panacinar emphysema is most commonly a result of alpha-1-protease inhibitor deficiency and pulmonary sequestration is a congenital malformation of the lower respiratory tract which results in a nonfunctioning mass of lung tissue.